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Sample records for mw combined heat

  1. Fouling Process and Control Measures for 50 MW Turbo Generator Set of Combined Heat and Power%热电联供50 MW汽轮发电机组结垢处理及管理措施

    Institute of Scientific and Technical Information of China (English)

    汪学峰

    2012-01-01

      介绍了自备发电站热电联供装置50 MW汽轮发电机组汽轮机叶片结垢的原因和危害,采用低温低压饱和湿蒸汽清洗去除叶片结垢,在生产运行中加强蒸汽、凝结水品质监督,使热电联供发电机组汽轮机叶片结垢、积盐情况得到了明显改善,因蒸汽、凝结水品质原因引起的非计划停机、停炉、停电等设备事故没有发生,提高了热电联供汽轮发电机组的运行效率,保障了机组高效、安全、稳定、经济运行。%  Introduction was made to the cause and harm of steam turbine blade fouling of 50 MW turbo generator set of combined heat and power providing for power plant. Low-temperature and low-saturation moist steam was adopted to remove the blade foul-ing. During production run, the quality supervision of steam and condensation water was strengthened to improve the situation of steam turbine blade fouling and salt accumulating of 50 MW turbo generator set of combined heat and power, so that there was no equipment breakdown such as unplanned shut-down, blow-off and power failure caused by the quality of steam and condensation water, which raised the operating efficiency of turbo generator set of combined heat and power, and ensured high-efficiency, safe, stable and economic operation.

  2. INTEGRATED GASIFICATION COMBINED CYCLE PROJECT 2 MW FUEL CELL DEMONSTRATION

    Energy Technology Data Exchange (ETDEWEB)

    FuelCell Energy

    2005-05-16

    With about 50% of power generation in the United States derived from coal and projections indicating that coal will continue to be the primary fuel for power generation in the next two decades, the Department of Energy (DOE) Clean Coal Technology Demonstration Program (CCTDP) has been conducted since 1985 to develop innovative, environmentally friendly processes for the world energy market place. The 2 MW Fuel Cell Demonstration was part of the Kentucky Pioneer Energy (KPE) Integrated Gasification Combined Cycle (IGCC) project selected by DOE under Round Five of the Clean Coal Technology Demonstration Program. The participant in the CCTDP V Project was Kentucky Pioneer Energy for the IGCC plant. FuelCell Energy, Inc. (FCE), under subcontract to KPE, was responsible for the design, construction and operation of the 2 MW fuel cell power plant. Duke Fluor Daniel provided engineering design and procurement support for the balance-of-plant skids. Colt Engineering Corporation provided engineering design, fabrication and procurement of the syngas processing skids. Jacobs Applied Technology provided the fabrication of the fuel cell module vessels. Wabash River Energy Ltd (WREL) provided the test site. The 2 MW fuel cell power plant utilizes FuelCell Energy's Direct Fuel Cell (DFC) technology, which is based on the internally reforming carbonate fuel cell. This plant is capable of operating on coal-derived syngas as well as natural gas. Prior testing (1992) of a subscale 20 kW carbonate fuel cell stack at the Louisiana Gasification Technology Inc. (LGTI) site using the Dow/Destec gasification plant indicated that operation on coal derived gas provided normal performance and stable operation. Duke Fluor Daniel and FuelCell Energy developed a commercial plant design for the 2 MW fuel cell. The plant was designed to be modular, factory assembled and truck shippable to the site. Five balance-of-plant skids incorporating fuel processing, anode gas oxidation, heat recovery

  3. Modular compact house substations for district heating with capacities of up to 1 MW. Modulare Fernwaermekompakthausstation bis 1 MW Leistung

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, F. (Mannheimer Versorgungs- und Verkehrsgesellschaft mbH (MVV), Mannheim (Germany)); Dausch, H.J. (Mannheimer Versorgungs- und Verkehrsgesellschaft mbH (MVV), Mannheim (Germany))

    1994-03-01

    The ever-increasing competition on the heating market has forced us - within the framework of overall optimization of district-heating service - to continue improving our house substantions as the main link between distribution lines and consumer installations. The aim is to develop a modern, high-tech 'product', capable of supplying any demand regardless of the technical parameters involved. Furthermore, it should integrate the best of the respective economic, functional, operational, and aesthetic attributes of this technology. These objectives provide us with very precisely definable demands on the various elements of our hourse substantions. The following considerations form the main focus of optimization: Compactness, the right concept to meet each individual case, coverage of a capacity range of up to 1 MW, managing the large variety of alternatives with the aid of a modular system, incorporating thermostats oriented to outside temperatures, resolving questions on integration of water-heating systems for domestic use into the substantion concepts, and designing system piping and instrumentation. However, investments as well as operating and maintenance costs should always be maintained well within the lowest possible parameters. This article presents the most important basic thinking on these points. It also provides information on some additional aims of optimization, references, and projects already completed. (orig.)

  4. Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    At their 2007 Summit in Heiligendamm, G8 leaders called on countries to 'adopt instruments and measures to significantly increase the share of combined heat and power (CHP) in the generation of electricity.' As a result, energy, economic, environmental and utility regulators are looking for tools and information to understand the potential of CHP and to identify appropriate policies for their national circumstances. This report forms the first part of the response. It includes answers to policy makers' questions about the potential economic, energy and environmental benefits of an increased policy commitment to CHP. It also includes for the first time integrated IEA data on global CHP installations, and analyses the benefits of increased CHP investment in the G8+5 countries. A companion report will be produced later in 2008 to document best practice policy approaches that have been used to expand the use of CHP in a variety of countries.

  5. Recent Results on Ion-Cyclotron and Combined Heating of Textor

    NARCIS (Netherlands)

    Koch, R.; Messiaen, A. M.; Ongena, J.; Vannieuwenhove, R.; Van Oost, G.; van Wassenhove, G.; Dumortier, P.; Durodie, F.; Vandenplas, P. E.; Vanesteer, D.; Vervier, M.; Weynants, R. R.; Finken, K.H.; Euringer, H.; Philipps, V.; Samm, U.; Unterberg, B.; Winter, J.; Bertschinger, G.; Esser, H. G.; Fuchs, G.; Giesen, B.; Hintz, E.; Hoenen, F.; Hutteman, P.; Konen, L.; Korten, M.; Koslowski, H. R.; KramerFlecken, A.; Lochter, M.; Mank, G.; Pospieszczyk, A.; Schweer, B.; Soltwisch, H.; Telesca, G.; Uhlemann, R.; Waidmann, G.; Wolf, G. H.; Boedo, J.; Gray, D.; Hillis, D. L.; Oyevaar, T.; Tammen, H. F.; Tanabe, T.; Ueda, Y.

    1995-01-01

    The recent experimental activity in the field of auxiliary heating and related topics on TEXTOR is reviewed. TEXTOR is equipped with up to 4 MW of ion cyclotron heating power and 3.4 MW of neutral beam injection. The combination of the radiating boundary concept with high auxiliary power has

  6. Unified field analysis method for IR/MW micro-mirror array beam combiner.

    Science.gov (United States)

    Tian, Yi; Sun, Gang; Yan, Hui; Zhang, Li; Li, Zhuo

    2014-07-01

    The aperture field integration method (AFIM) is proposed and utilized to efficiently compute the field distributions of infrared/microwave (IR/MW) micro-mirror array beam combiners, including the MW near-field distribution and the IR far-field distribution. The MW near-field distributions of single-dielectric-layer beam combiners with 1, 11, and 101 micromirrors are analyzed by AFIM. Compared to the commonly used multilevel fast multipole method (MLFMM) in the computation of MW near-field distribution, the memory requirement and CPU time consumption are reduced drastically from 16.92 GB and 3.26 h to 0.66 MB and 0.55 s, respectively. The calculation accuracy is better than 96%, when the MW near-field distribution is computed. The IR far-field computational capability is validated by comparing the results obtained through AFIM and experiment. The MW near field and IR far field of a circular and a square shape of three-layer micro-mirror array beam combiners are also analyzed. Four indicators E pv , E rms , φ pv , and φ rms representing the amplitude and phase variations are proposed to evaluate the MW near-field uniformity. The simulation results show that the increase of beam combiner size can improve the uniformity of the MW near field, and that the square shape has less influence on the uniformity of the MW near field than the circular one. The zeroth-order diffraction primary maximum intensity of the IR far field is decreased by 1/cos 2  α 0 times compared to that of the equivalent mirror, where α 0 is the oblique angle of each micromirror. When the periodic length of the micro-mirror array is less than 0.1 mm, the position of the secondary maximum will exceed the size of the focal plane array. Simultaneously, the half-width of the zeroth-order diffraction primary maximum is less than the size of a single pixel. Thus, IR images with high quality will be obtained. The simulation results show that the AFIM as a unified method can be applied to design

  7. Combined Heat and Power

    Science.gov (United States)

    CHP is on-site electricity generation that captures the heat that would otherwise be wasted to provide useful thermal energy such as steam or hot water than can be used for space heating, cooling, domestic hot water and industrial processes.

  8. Design for the 145MW blast furnance gas firing gas turbine combined cycle plant

    Energy Technology Data Exchange (ETDEWEB)

    Takano, H. (Kawasaki Steel Corp., Chiba (Japan). Technical Research Lab.); Kitauchi, Y.; Hiura, H. (Mitsubishi Heavy Industries Ltd., Takasago, Hyogo (Japan). Takasago Works)

    1988-01-01

    A 145 MW blast furnance gas firing gas turbine combined cycle plant was designed and installed in a steel works of Japan as a repowering unit. A 124 MW large scale gas turbine with turbine inlet temperature 1150{sup {degrees}}C (1423 K) was adopted as a core engine for the combined cycle plant. The fuel of this gas turbine is blast furnace gas mixed with coke oven gas which are byproducts in steel works, and the calorific value of the mixed gas to be controlled is about 1000 kcal/Nm{sup 3} (4187 kJ/Nm{sup 3}). A specially designed multi-cannular type combustor was developed to burn such a low BTV fuel. The gas turbine, generator, steam turbine and fuel gas compressor are connected to make a single shaft configuration. As a result of this introducing the gas turbine combined cycle plant, the plant thermal efficiency was achieved above 45% (at NET) and the total electricity generation in the works is increased from 243 MW to 317 MW. This paper describes the design features of this combined cycle plant.

  9. Infrared/microwave (IR/MW) micromirror array beam combiner design and analysis.

    Science.gov (United States)

    Tian, Yi; Lv, Lijun; Jiang, Liwei; Wang, Xin; Li, Yanhong; Yu, Haiming; Feng, Xiaochen; Li, Qi; Zhang, Li; Li, Zhuo

    2013-08-01

    We investigated the design method of an infrared (IR)/microwave (MW) micromirror array type of beam combiner. The size of micromirror is in microscopic levels and comparable to MW wavelengths, so that the MW will not react in these dimensions, whereas the much shorter optical wavelengths will be reflected by them. Hence, the MW multilayered substrate was simplified and designed using transmission line theory. The beam combiner used an IR wavefront-division imaging technique to reflect the IR radiation image to the unit under test (UUT)'s pupil in a parallel light path. In addition, the boresight error detected by phase monopulse radar was analyzed using a moment-of method (MoM) and multilevel fast multipole method (MLFMM) acceleration technique. The boresight error introduced by the finite size of the beam combiner was less than 1°. Finally, in order to verify the wavefront-division imaging technique, a prototype of a micromirror array was fabricated, and IR images were tested. The IR images obtained by the thermal imager verified the correctness of the wavefront-division imaging technique.

  10. MW-scale ICRF plasma heating using IGBT switches in a multi-pulse scheme

    Science.gov (United States)

    Be'ery, I.; Kogan, K.; Seemann, O.

    2015-06-01

    Solid-state silicon switches are cheap and reliable option for 1-10 MHz RF power sources, required for plasma ion cyclotron RF heating (ICRF). The large `on' resistance of MOSFET and similar devices limits their power delivery to a few tens of kW per switch. Low resistivity devices, such as IGBT, suffer from large `off' switching time, which limits their useful frequency range and increases the power dissipated in the switch. Here we demonstrate more than 0.8 MW circulated RF power at 2 MHz using only three high voltage IGBT switches. The circuit uses the fast `on' switching capability of the IGBTs to generate high-Q pulse train. This operation mode also simplifies the measurement of RF coupling between the antenna and the plasma.

  11. PM-GCD - a combined IR-MW satellite technique for frequent retrieval of heavy precipitation

    Science.gov (United States)

    Casella, D.; Dietrich, S.; di Paola, F.; Formenton, M.; Mugnai, A.; Porcù, F.; Sanò, P.

    2012-01-01

    Precipitation retrievals based on measurements from microwave (MW) radiometers onboard low-Earth-orbit (LEO) satellites can reach high level of accuracy - especially regarding convective precipitation. At the present stage though, these observations cannot provide satisfactory coverage of the evolution of intense and rapid precipitating systems. As a result, the obtained precipitation retrievals are often of limited use for many important applications - especially in supporting authorities for flood alerts and weather warnings. To tackle this problem, over the past two decades several techniques have been developed combining accurate MW estimates with frequent infrared (IR) observations from geosynchronous (GEO) satellites, such as the European Meteosat Second Generation (MSG). In this framework, we have developed a new fast and simple precipitation retrieval technique which we call Passive Microwave - Global Convective Diagnostic, (PM-GCD). This method uses MW retrievals in conjunction with the Global Convective Diagnostic (GCD) technique which discriminates deep convective clouds based on the difference between the MSG water vapor (6.2 μm) and thermal-IR (10.8 μm) channels. Specifically, MSG observations and the GCD technique are used to identify deep convective areas. These areas are then calibrated using MW precipitation estimates based on observations from the Advanced Microwave Sounding Unit (AMSU) radiometers onboard operational NOAA and Eumetsat satellites, and then finally propagated in time with a simple tracking algorithm. In this paper, we describe the PM-GCD technique, analyzing its results for a case study that refers to a flood event that struck the island of Sicily in southern Italy on 1-2 October 2009.

  12. Thermal power output determination of 2 MW heat source by using of thermocouples

    Science.gov (United States)

    Holubcik, Michal; Vician, Peter; Palacka, Matej

    2016-06-01

    Experiment is an operation or procedure carried out under controlled conditions in order to discover an unknown effect or law, to test or establish a hypothesis, or to illustrate a known law. The most important part of the experiment is to evaluate the measured values. Measurement accuracy depends on a number of factors. Deviations of instruments cannot eliminate or influence if it is neglect the possibility of using more precise measuring equipment. Another way for the most accurate results can be calibration. Calibration allows achieve measurement values with relatively high accuracy using less precision instruments. The paper deals about the problematic of thermal power measurement accuracy. Thermal power was measured on heat source with nominal thermal power 2 MW by using direct calorimetric method. There were used ultrasonic flow meter and type K thermocouples. Type K thermocouples are not very suitable for these applications because of their low precision. The paper presents the possibility of using calibrated thermocouples for the thermal power measurement with acceptable accuracy.

  13. Surface latent heat flux anomalies prior to the Indonesia Mw9.0 earthquake of 2004

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The temporal and spatial variations of surface latent heat flux (SLHF) before and after the Mw9.0 earthquake that occurred on the west coast of Sumatra, Indonesia on 26 December 2004 are summarized. It is found that before the earthquake significant SLHF anomalies occurred at the epicentral area and its vicinity. The largest SLHF anomaly occurred on the subduction zone in the middle part of Burma micro-plate, where the middle part of the rupture zone is located and the aftershocks are concentrated. The developments of the anomaly involved growing of the anomaly from small to large and spreading of the anomaly from disordered to concentrated. The anomaly began to occur on the east extensional boundary of the Burma micro-plate and its adjacent oceanic basin, and then propagated to the west compressive boundary, where the subduction zone exists. Finally, the anomaly disappeared after the main shock. The seismic source is considered to be a dissipation system. The increase of stress prior to an earthquake may enhance the exchange of energy and material between the seismic source system and the outer system, resulting in the increase of the rate of energy exchange between sea surface and atmosphere, which is believed to be the main reason of the generation of SLHF anomaly.

  14. Prototype solar heating and combined heating cooling systems

    Science.gov (United States)

    1978-01-01

    The design and development of eight prototype solar heating and combined heating and cooling systems is discussed. The program management and systems engineering are reported, and operational test sites are identified.

  15. Development of a 2 MW CW Waterload for Electron Cyclotron Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    R. Lawrence,Ives; Maxwell Mizuhara; George Collins; Jeffrey Neilson; Philipp Borchard

    2012-11-09

    Calabazas Creek Research, Inc. developed a load capable of continuously dissipating 2 MW of RF power from gyrotrons. The input uses HE11 corrugated waveguide and a rotating launcher to uniformly disperse the power over the lossy surfaces in the load. This builds on experience with a previous load designed to dissipate 1 MW of continuous RF power. The 2 MW load uses more advanced RF dispersion to double the capability in the same size device as the 1 MW load. The new load reduces reflected power from the load to significantly less than 1 %. This eliminates requirements for a preload to capture reflected power. The program updated control electronics that provides all required interlocks for operation and measurement of peak and average power. The program developed two version of the load. The initial version used primarily anodized aluminum to reduce weight and cost. The second version used copper and stainless steel to meet specifications for the ITER reactor currently under construction in France. Tests of the new load at the Japanese Atomic Energy Agency confirmed operation of the load to a power level of 1 MW, which is the highest power currently available for testing the load. Additional tests will be performed at General Atomics in spring 2013. The U.S. ITER organization will test the copper/stainless steel version of the load in December 2012 or early in 2013. Both loads are currently being marketed worldwide.

  16. Combination solar photovoltaic heat engine energy converter

    Science.gov (United States)

    Chubb, Donald L.

    1987-01-01

    A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

  17. Radiological considerations on multi-MW targets Part II After-heat and temperature distribution in packed tantalum spheres

    CERN Document Server

    Magistris, M

    2005-01-01

    CERN is designing a Superconducting Proton Linac (SPL) to provide a 2.2GeV, 4MW proton beam to feed facilities like, for example, a future Neutrino Factory or a Neutrino SuperBeam. One of the most promising target candidates is a stationary consisting of a Ti container filled with small Ta pellets. The power deposited as heat by the radioactive nuclides (the so-called after-heat) can considerably increase the target temperature after ceasing operation, if no active cooling is provided. An estimate of the induced radioactivity and after-heat was performed with the FLUKA Monte Carlo code. To estimate the highest temperature reached inside the target, the effective thermal conductivity of packed spheres was evaluated using the basic cell method. A method for estimating the contribution to heat transmission from radiation is also discussed1).

  18. Study of regeneration system of 300 MW power unit based on nondeaerating heat balance diagram at reduced load

    Science.gov (United States)

    Esin, S. B.; Trifonov, N. N.; Sukhorukov, Yu. G.; Yurchenko, A. Yu.; Grigor'eva, E. B.; Snegin, I. P.; Zhivykh, D. A.; Medvedkin, A. V.; Ryabich, V. A.

    2015-09-01

    More than 30 power units of thermal power stations, based on the nondeaerating heat balance diagram, successfully operate in the former Soviet Union. Most of them are power units with a power of 300 MW, equipped with HTGZ and LMZ turbines. They operate according to a variable electric load curve characterized by deep reductions when undergoing night minimums. Additional extension of the range of power unit adjustment makes it possible to maintain the dispatch load curve and obtain profit for the electric power plant. The objective of this research is to carry out estimated and experimental processing of the operating regimes of the regeneration system of steam-turbine plants within the extended adjustment range and under the conditions when the constraints on the regeneration system and its equipment are removed. Constraints concerning the heat balance diagram that reduce the power unit efficiency when extending the adjustment range have been considered. Test results are presented for the nondeaerating heat balance diagram with the HTGZ turbine. Turbine pump and feed electric pump operation was studied at a power unit load of 120-300 MW. The reliability of feed pump operation is confirmed by a stable vibratory condition and the absence of cavitation noise and vibration at a frequency that characterizes the cavitation condition, as well as by oil temperature maintenance after bearings within normal limits. Cavitation performance of pumps in the studied range of their operation has been determined. Technical solutions are proposed on providing a profitable and stable operation of regeneration systems when extending the range of adjustment of power unit load. A nondeaerating diagram of high-pressure preheater (HPP) condensate discharge to the mixer. A regeneration system has been developed and studied on the operating power unit fitted with a deaeratorless thermal circuit of the system for removing the high-pressure preheater heating steam condensate to the mixer

  19. Combined MW-IR Precipitation Evolving Technique (PET of convective rain fields

    Directory of Open Access Journals (Sweden)

    F. Di Paola

    2012-11-01

    Full Text Available This paper describes a new multi-sensor approach for convective rain cell continuous monitoring based on rainfall derived from Passive Microwave (PM remote sensing from the Low Earth Orbit (LEO satellite coupled with Infrared (IR remote sensing Brightness Temperature (TB from the Geosynchronous (GEO orbit satellite. The proposed technique, which we call Precipitation Evolving Technique (PET, propagates forward in time and space the last available rain-rate (RR maps derived from Advanced Microwave Sounding Units (AMSU and Microwave Humidity Sounder (MHS observations by using IR TB maps of water vapor (6.2 μm and thermal-IR (10.8 μm channels from a Spinning Enhanced Visible and Infrared Imager (SEVIRI radiometer. PET is based on two different modules, the first for morphing and tracking rain cells and the second for dynamic calibration IR-RR. The Morphing module uses two consecutive IR data to identify the motion vector to be applied to the rain field so as to propagate it in time and space, whilst the Calibration module computes the dynamic relationship between IR and RR in order to take into account genesis, extinction or size variation of rain cells. Finally, a combination of the Morphing and Calibration output provides a rainfall map at IR space and time scale, and the whole procedure is reiterated by using the last RR map output until a new MW-based rainfall is available. The PET results have been analyzed with respect to two different PM-RR retrieval algorithms for seven case studies referring to different rainfall convective events. The qualitative, dichotomous and continuous assessments show an overall ability of this technique to propagate rain field at least for 2–3 h propagation time.

  20. Heat pumps in combined heat and power systems

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    2014-01-01

    of the considered cases. When considering a case where the heat pump is located at a CHP (combined heat and power) plant, a configuration that increases the DH return temperature proposes the lowest operation cost, as low as 12 EUR MWh-1 for a 90 °C e 40 °C DH network. Considering the volumetric heating capacity......Heat pumps have previously been proposed as a way to integrate higher amounts of renewable energy in DH (district heating) networks by integrating, e.g., wind power. The paper identifies and compares five generic configurations of heat pumps in DH systems. The operational performance......, a third configuration is superior in all cases. Finally, the three most promising heat pump configurations are integrated in a modified PQ-diagram of the CHP plant. Each show individual advantages, and for two, also disadvantages in order to achieve flexible operation....

  1. Heat loss analysis-based design of a 12 MW wind power generator module having an HTS flux pump exciter

    Science.gov (United States)

    Sung, Hae-Jin; Go, Byeong-Soo; Jiang, Zhenan; Park, Minwon; Yu, In-Keun

    2016-11-01

    The development of an effective high-temperature superconducting (HTS) generator is currently a research focus; however, the reduction of heat loss of a large-scale HTS generator is a challenge. This study deals with a heat loss analysis-based design of a 12 MW wind power generator module having an HTS flux pump exciter. The generator module consists of an HTS rotor of the generator and an HTS flux pump exciter. The specifications of the module were described, and the detailed configuration of the module was illustrated. For the heat loss analysis of the module, the excitation loss of the flux pump exciter, eddy current loss of all of the structures in the module, radiation loss, and conduction loss of an HTS coil supporter were assessed using a 3D finite elements method program. In the case of the conduction loss, different types of the supporters were compared to find out the supporter of the lowest conduction loss in the module. The heat loss analysis results of the module were reflected in the design of the generator module and discussed in detail. The results will be applied to the design of large-scale superconducting generators for wind turbines including a cooling system.

  2. PM-GCD – a combined IR–MW satellite technique for frequent retrieval of heavy precipitation

    Directory of Open Access Journals (Sweden)

    D. Casella

    2012-01-01

    Full Text Available Precipitation retrievals based on measurements from microwave (MW radiometers onboard low-Earth-orbit (LEO satellites can reach high level of accuracy – especially regarding convective precipitation. At the present stage though, these observations cannot provide satisfactory coverage of the evolution of intense and rapid precipitating systems. As a result, the obtained precipitation retrievals are often of limited use for many important applications – especially in supporting authorities for flood alerts and weather warnings. To tackle this problem, over the past two decades several techniques have been developed combining accurate MW estimates with frequent infrared (IR observations from geosynchronous (GEO satellites, such as the European Meteosat Second Generation (MSG. In this framework, we have developed a new fast and simple precipitation retrieval technique which we call Passive Microwave – Global Convective Diagnostic, (PM-GCD. This method uses MW retrievals in conjunction with the Global Convective Diagnostic (GCD technique which discriminates deep convective clouds based on the difference between the MSG water vapor (6.2 μm and thermal-IR (10.8 μm channels. Specifically, MSG observations and the GCD technique are used to identify deep convective areas. These areas are then calibrated using MW precipitation estimates based on observations from the Advanced Microwave Sounding Unit (AMSU radiometers onboard operational NOAA and Eumetsat satellites, and then finally propagated in time with a simple tracking algorithm. In this paper, we describe the PM-GCD technique, analyzing its results for a case study that refers to a flood event that struck the island of Sicily in southern Italy on 1–2 October 2009.

  3. Residential CO2 Heat Pump System for Combined Space Heating and Hot Water Heating

    OpenAIRE

    Stene, Jørn

    2004-01-01

    Carbon dioxide (CO2, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO2 heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO2 heat pump systems for combined space heating and hot water hea...

  4. Combined Heat and Power and Emissions Trading

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The aim of this IEA Information Paper is to help policy makers and other stakeholders understand the challenges facing the incorporation of high efficiency combined heat and power (CHP) into greenhouse gas (GHG) Emissions Trading Schemes (ETSs) -- and to propose options for overcoming them.

  5. Thermal Energy Corporation Combined Heat and Power Project

    Energy Technology Data Exchange (ETDEWEB)

    Turner, E. Bruce [Thermal Energy Corporation, Houston, TX (United States); Brown, Tim [Thermal Energy Corporation, Houston, TX (United States); Mardiat, Ed [Burns and McDonnell Engineering Company, Inc., Kansas City, MI (United States)

    2011-12-31

    To meet the planned heating and cooling load growth at the Texas Medical Center (TMC), Thermal Energy Corporation (TECO) implemented Phase 1 of a Master Plan to install an additional 32,000 tons of chilled water capacity, a 75,000 ton-hour (8.8 million gallon) Thermal Energy Storage (TES) tank, and a 48 MW Combined Heat and Power (CHP) system. The Department of Energy selected TMC for a $10 million grant award as part of the Financial Assistance Funding Opportunity Announcement, U.S. Department of Energy National Energy Technology, Recovery Act: Deployment of Combined Heat and Power (CHP) Systems, District Energy Systems, Waste Energy Recovery Systems, and Efficiency Industrial Equipment Funding Opportunity Number: DE-FOA-0000044 to support the installation of a new 48 MW CHP system at the TMC located just outside downtown Houston. As the largest medical center in the world, TMC is home to many of the nation's best hospitals, physicians, researchers, educational institutions, and health care providers. TMC provides care to approximately six million patients each year, and medical instruction to over 71,000 students. A medical center the size of TMC has enormous electricity and thermal energy demands to help it carry out its mission. Reliable, high-quality steam and chilled water are of utmost importance to the operations of its many facilities. For example, advanced medical equipment, laboratories, laundry facilities, space heating and cooling all rely on the generation of heat and power. As result of this project TECO provides this mission critical heating and cooling to TMC utilizing a system that is both energy-efficient and reliable since it provides the capability to run on power independent of the already strained regional electric grid. This allows the medical center to focus on its primary mission providing top quality medical care and instruction without worrying about excessive energy costs or the loss of heating and cooling due to the risk of power

  6. Microphysics of Clouds Initiated from a 1000 MW Dry Heat Source in Comparison with Environmental Clods--A Statistical Study.

    Science.gov (United States)

    van Dinh, Pham; Bénech, Bruno; Radke, Lawrence F.

    1986-08-01

    To evaluate potential atmospheric impacts of wate heat released by dry cooling towers, studies have been made of an oil burning system (the `Météotron'), which emits sensible heat at a rate of 1000 MW and large quantities of aerosol particles into the atmosphere. Out of the 15 `burns' made during 1979, 12 times the rising column of smoke was capped with a cloud formation. The structures of these clouds were investigated with an instrumented aircraft. The clouds capping the Météotron (A) and the natural clouds unaffected by it (N) were compared by means of the Student's t applied to the mean liquid water content (LWC), droplet mean diameter (Dm) and droplet concentration (conc.) The N-clouds consisted essentially of stratus, cumulus and stratocumulus, developing sometimes up to 2000 m (AGL). Compared to the N-clouds, the volume of the A-clouds were similar or smaller, despite the fact that their condensation levels were sometimes lower and their tops generally higher. Generally, for both A- and N-clouds, the conc decreased with height while Dm and LWC increased; the increase of LWC is associated with the increase of Dm and the decrease of conc. In most cases, the A-clouds contained more droplets but with smaller mean diameter than the N-clouds (statistically significant at the 95% confidence level). This led to generally lower LWC in the A-clouds than in the N-clouds. This result is particularly noticeable when comparing cloud properties at the same height. The higher droplet concentration apparently did not result from a higher concentration of cloud condensation nuclei. The A-cloud characteristics were similar to those of freshly formed clouds. Their differences from N-clouds seem largely due to the heart released; the effect of the aerosol from Météotron is comparatively small.

  7. Chapter 23: Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    Simons, George [Itron, Davis, CA (United States); Barsun, Stephan [Itron, Davis, CA (United States)

    2016-11-01

    This protocol defines a combined heat and power (CHP) measure as a system that sequentially generates both electrical energy and useful thermal energy from one fuel source at a host customer's facility or residence. This protocol is aimed primarily at regulators and administrators of ratepayer-funded CHP programs; however, project developers may find the protocol useful to understand how CHP projects are evaluated.

  8. Anaerobic Digestion and Combined Heat and Power Study

    Energy Technology Data Exchange (ETDEWEB)

    Frank J. Hartz

    2011-12-30

    One of the underlying objectives of this study is to recover the untapped energy in wastewater biomass. Some national statistics worth considering include: (1) 5% of the electrical energy demand in the US is used to treat municipal wastewater; (2) This carbon rich wastewater is an untapped energy resource; (3) Only 10% of wastewater treatment plants (>5mgd) recover energy; (4) Wastewater treatment plants have the potential to produce > 575 MW of energy nationwide; and (5) Wastewater treatment plants have the potential to capture an additional 175 MW of energy from waste Fats, Oils and Grease. The WSSC conducted this study to determine the feasibility of utilizing anaerobic digestion and combined heat and power (AD/CHP) and/or biosolids gasification and drying facilities to produce and utilize renewable digester biogas. Digester gas is considered a renewable energy source and can be used in place of fossil fuels to reduce greenhouse gas emissions. The project focus includes: (1) Converting wastewater Biomass to Electricity; (2) Using innovative technologies to Maximize Energy Recovery; and (3) Enhancing the Environment by reducing nutrient load to waterways (Chesapeake Bay), Sanitary Sewer Overflows (by reducing FOG in sewers) and Greenhouse Gas Emissions. The study consisted of these four tasks: (1) Technology screening and alternative shortlisting, answering the question 'what are the most viable and cost effective technical approaches by which to recover and reuse energy from biosolids while reducing disposal volume?'; (2) Energy recovery and disposal reduction potential verification, answering the question 'how much energy can be recovered from biosolids?'; (3) Economic environmental and community benefit analysis, answering the question 'what are the potential economic, environmental and community benefits/impacts of each approach?'; and (4) Recommend the best plan and develop a concept design.

  9. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

  10. Fundamental Study of a Combined Hyperthermia System with RF Capacitive Heating and Interstitial Heating

    OpenAIRE

    Saitoh, Yoshiaki; Hori, Junichi; 斉藤, 義明; 堀, 潤一

    2001-01-01

    Interstitial RF heating with an inserted electrode allows the heating position selection in a subject, but the narrow heating region is problematic. This study elucidates development of new interstitial RF heating methods, combining with external RF heating using paired electrodes, heating the subject broadly in advance in order to selectively extend the heating region. Two kinds of heating system were developed by controlling a differential mode and a common mode of RF currents. Heating expe...

  11. Fundamental Study of a Combined Hyperthermia System with RF Capacitive Heating and Interstitial Heating

    OpenAIRE

    Saitoh, Yoshiaki; Hori, Junichi; 斉藤, 義明; 堀, 潤一

    2001-01-01

    Interstitial RF heating with an inserted electrode allows the heating position selection in a subject, but the narrow heating region is problematic. This study elucidates development of new interstitial RF heating methods, combining with external RF heating using paired electrodes, heating the subject broadly in advance in order to selectively extend the heating region. Two kinds of heating system were developed by controlling a differential mode and a common mode of RF currents. Heating expe...

  12. Predicting heat flow in the 2001 Bhuj earthquake (Mw=7.7 region of Kachchh (Western India, using an inverse recurrence method

    Directory of Open Access Journals (Sweden)

    V. P. Dimri

    2011-09-01

    Full Text Available Terrestrial heat flow is considered an important parameter in studying the regional geotectonic and geodynamic evolutionary history of any region. However, its distribution is still very uneven. There is hardly any information available for many geodynamically important areas. In the present study, we provide a methodology to predict the surface heat flow in areas, where detailed seismic information such as depth to the lithosphere-asthenosphere boundary (LAB and crustal structure is known. The tool was first tested in several geotectonic blocks around the world and then used to predict the surface heat flow for the 2001 Bhuj earthquake region of Kachchh, India, which has been seismically active since historical times and where aftershock activity is still continuing nine years after the 2001 main event. Surface heat flow for this region is estimated to be about 61.3 mW m−2. Beneath this region, heat flow input from the mantle as well as the temperatures at the Moho are quite high at around 44 mW m−2 and 630 °C, respectively, possibly due to thermal restructuring of the underlying crust and mantle lithosphere. In absence of conventional data, the proposed tool may be used to estimate a first order heat flow in continental regions for geotectonic studies, as it is also unaffected by the subsurface climatic perturbations that percolate even up to 2000 m depth.

  13. 吸收式热泵回收300MW机组循环水余热的设计研究%Design and Research of Absorption Type Heat Pump Recycling 300MW Unit Circulating Water Waste Heat

    Institute of Scientific and Technical Information of China (English)

    马光耀

    2015-01-01

    Low temperature waste heat of 300MW unit circulating water in a plant was recycled through the ab-sorption heatpump,circulating water of different temperature has great influence on the design scheme of heat pump.In this design, the temperature difference of heat pump import for the circulating wateris 7℃,the heatpump circulating water inlet temperature is 31~35℃,heating extraction steam pressure is about 0.3MPa,steam consump-tion for the steam driving is 270t/h,The temperature of hot topwater after heating by heat pump increases from 43℃ to 74℃,heat recovery capacity of the heat pumpis 131tMo,the whole heating capacity of the heat pump is about 318MW.%对某厂300MW机组循环水的低温余热通过吸收式热泵进行回收,不同的循环水温度对热泵的设计方案有着很大的影响.该设计中循环水进出热泵温差为7℃,热泵进口处循环水温度为31~35℃,采暖抽汽压力约为0.3MPa,驱动蒸汽用汽量为270t/h,热网水经热泵加热后温度从43℃升至74℃,热泵余热回收量为131MW,热泵总的制热量约为318MW.

  14. Deposition and high temperature corrosion in a 10 MW straw

    DEFF Research Database (Denmark)

    Michelsen, Hanne Philbert; Frandsen, Flemming; Dam-Johansen, Kim

    1998-01-01

    Deposition and corrosion measurements were conducted at a 10 MW wheat straw fired stoker boiler used for combined power and heat production. The plant experiences major problems with deposits on the heat transfer surfaces, and test probes have shown enhanced corrosion due to selective corrosion...

  15. Combined Steady-State and Dynamic Heat Exchanger Experiment

    Science.gov (United States)

    Luyben, William L.; Tuzla, Kemal; Bader, Paul N.

    2009-01-01

    This paper describes a heat-transfer experiment that combines steady-state analysis and dynamic control. A process-water stream is circulated through two tube-in-shell heat exchangers in series. In the first, the process water is heated by steam. In the second, it is cooled by cooling water. The equipment is pilot-plant size: heat-transfer areas…

  16. Interpretation of the deep cracking phenomenon of tungsten monoblock targets observed in high-heat-flux fatigue tests at 20 MW/m{sup 2}

    Energy Technology Data Exchange (ETDEWEB)

    Li, Muyuan; You, Jeong-Ha, E-mail: you@ipp.mpg.de

    2015-12-15

    Highlights: • A theoretical interpretation is presented for deep crack of W monoblocks at 20 MW/m{sup 2}. • A consecutive process of crack initiation and growth was modeled in two stages. • The lifetime to crack initiation and the driving force of fracture are assessed. • Numerical predictions in this study agree well with the experimental findings. - Abstract: The HHF qualification tests conducted on the ITER divertor target prototypes showed that the tungsten monoblock armor suffered from deep cracking due to fatigue, when the applied high-heat-flux load approaches 20 MW/m{sup 2}. In spite of the critical implication of the deep cracking of armor on the structural integrity of a whole target component, no rigorous interpretation has been given to date. In this paper, a theoretical interpretation of the observed deep cracking feature is presented. A two-stage modeling approach is employed where deep cracking is thought to be a consecutive process of crack initiation and crack growth, which is assumed to be caused by plastic fatigue and brittle facture, respectively. The fatigue lifetime to crack initiation on the armor surface and the crack tip load of brittle fracture are assessed as a function of crack length and heat flux loads. The potential mechanisms of deep cracking are discussed for a typical slow transient high-heat-flux load cycle. It is shown that the quantitative predictions delivered in this study agree well with the observed findings offering insight into the nature of tungsten armor failure.

  17. Assessment of advanced small-scale combined heat and power production

    Energy Technology Data Exchange (ETDEWEB)

    Spitzer, J. [Joanneum Research (Austria)

    1996-12-31

    To increase the share of renewable energy sources, bioenergy has to be used for electricity generation, preferably in combined heat and power (CHP) production systems, besides its traditional use in space heating. The need for small-scale, i.e. below 5 MW{sub el}, CHP production arises from the fact that a considerable portion of the available solid biofuels may not be transported over long distances for economic reasons and that in many cases the heat demand is below 10 MW{sub el} in district heating schemes in communities with less than 10 000 inhabitants. The available technical options have to be assessed with respect to performance, reliability and economy. Such an assessment has been performed in a study where the following options have been compared: Gasification - combustion engine or gas turbine; Combustion - steam turbine/engine; Combustion - hot air turbine; Combustion - Stirling engine. While conventional steam cycle systems are available and reliable they are generally not economical in the power range under consideration. Among the other systems, which are not yet commercially available, the Stirling engine system seems to be attractive in the power range below 500 kW{sub el} and the hot air system could close the gap to the steam cycle systems, i.e. cover the power range between 0.5 and 5.0 MW{sub el}. Gasification schemes seem less suitable: The power generation part (combustion engine and gas turbine) is well established for natural gas, with the combustion engine in the lower (<5 MW{sub el}) and the gas turbine in the higher (>5MW{sub el}) power range. However, the gas quality needed for the operation of a combustion engine requires expensive pre-treatment of the gas from wood gasification so that this scheme is less attractive for the power range under consideration. These conclusions lead to R and D efforts in Austria in two directions: Hot air turbine: A utility demonstration plant is under construction with a power of 1 600 kW{sub el

  18. Prototype solar heating and combined heating and cooling systems

    Science.gov (United States)

    1978-01-01

    Designs were completed, hardware was received, and hardware was shipped to two sites. A change was made in the heat pump working fluid. Problem investigation of shroud coatings for the collector received emphasis.

  19. Commercialisation of fuel cells for combined heat and power (CHP) application

    Science.gov (United States)

    Packer, Julian

    1992-01-01

    Combined heat and power or co-generation is an ideal application for the fuel cell. This paper has been written from the perspective of a current designer, builder and operator of small-scale (i.e. sub 1 MW) combined heat and power. Conventional current CHP is described together with typical applications. The perceived advantages of fuel cells are also discussed together with the potential for fuel cells opening up currently unapproachable markets. Various matters relevant to the application of fuel cells are also described including: initial and life costs for fuel cells CHP systems; maintenance requirements, security of supply requirements. In addition to these commercial aspects, technical issues including interfacing to building systems, control, protection, monitoring, operating procedures and performance are also discussed.

  20. Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems

    Science.gov (United States)

    Milcarek, Ryan J.; Wang, Kang; Falkenstein-Smith, Ryan L.; Ahn, Jeongmin

    2016-02-01

    Currently the role of fuel cells in future power generation is being examined, tested and discussed. However, implementing systems is more difficult because of sealing challenges, slow start-up and complex thermal management and fuel processing. A novel furnace system with a flame-assisted fuel cell is proposed that combines the thermal management and fuel processing systems by utilizing fuel-rich combustion. In addition, the flame-assisted fuel cell furnace is a micro-combined heat and power system, which can produce electricity for homes or businesses, providing resilience during power disruption while still providing heat. A micro-tubular solid oxide fuel cell achieves a significant performance of 430 mW cm-2 operating in a model fuel-rich exhaust stream.

  1. Combined heat and power plants with parallel tandem steam turbines; Smaaskalig kraftvaerme med parallellkopplade tandemturbiner

    Energy Technology Data Exchange (ETDEWEB)

    Steinwall, Pontus; Norstroem, Urban; Pettersson, Camilla; Oesterlin, Erik

    2004-12-01

    We investigate the technical and economical conditions for a concept with parallel coupled tandem turbines in small scale combined heat and power plants fired with bio-fuel and waste. Performance and heat production costs at varying electricity prices for the concept with two smaller tandem coupled steam turbines has been compared to the traditional concept with one single multi-staged turbine. Three different types of plants have been investigated: - Bio fuelled CHP plant with thermal capacity of 15 MW{sub th}; - Waste fired CHP plant with thermal capacity of 20 MW{sub th}; - Bio fuelled CHP plant with thermal capacity of 25 MW{sub th}. The simple steam turbines (Curtis turbines) used in the tandem arrangement has an isentropic efficiency of about 49 to 53% compared to the multi-staged steam turbines with isentropic efficiency in the range of 59% to 81%. The lower isentropic efficiency for the single staged turbines is to some extent compensated at partial load when one of the two turbines can be shut down leading to better operational conditions for the one still in operation. For concepts with saturated steam at partial load below 50% the tandem arrangements presents higher electricity efficiency than the conventional single turbine alternative. The difference in annual production of electricity is therefore less than the difference in isentropic efficiency for the two concepts. Production of electricity is between 2% and 42% lower for the tandem arrangements in this study. Investment costs for the turbine island has been calculated for the two turbine concepts and when the costs for turbines, generator, power transmission, condensing system, piping system, buildings, assembling, commissioning and engineering has been added the sum is about the same for the two concepts. For the bio-fuelled plant with thermal capacity of 15 MW{sub th} the turbine island amount to about 10-12 MSEK and about 13-15 MSEK for the waste fired plant with a thermal capacity of 20 MW

  2. Heat Balance Research on 3MW Marine Wind Turbine's Engine Room%3MW海上风力发电机机舱热平衡设计

    Institute of Scientific and Technical Information of China (English)

    周年勇; 蒋彦龙; 刘志丽; 康娜

    2011-01-01

    According to the analysis of engine room structure and heat-dissipating of different components and environmental operating requirements of 3MW Wind Turbine System, heat balance design of Wind Turbine's engine room is carried out. Then calculation method of the heat load of engine room including the components heat load,outside heat load and fresh air heat load are proposed. At the same time,heat load changing characteristics of the engine room is obtained under the cooling method of jetting and influence of factors such as air temperature and speed and gray scale of the engine room to heat balance of the cabin is researched. This work could be helpful for the optimization of large-capacity Wind Turbine's cooling system.%以3MW海上风力发电机为研究对象,在考察其机舱布置结构、主要部件散热情况及环境要求的基础上,对机舱进行了热平衡设计,建立了机舱热平衡方程;提出了舱内部件载荷、机舱内外对流换热系数、舱内正压维持新风量的计算方法;获得了射流冷却方式下的舱内热载荷变化特性;并研究了舱内外空气温度、速度、舱体表面灰度等因素对机舱热平衡的影响.研究工作对于大容量风力发电冷却系统的设计优化具有参考价值.

  3. A 31 mW, 280 fs passively mode-locked fiber soliton laser using a high heat-resistant SWNT/P3HT saturable absorber coated with siloxane.

    Science.gov (United States)

    Ono, Takato; Hori, Yuichiro; Yoshida, Masato; Hirooka, Toshihiko; Nakazawa, Masataka; Mata, Junji; Tsukamoto, Jun

    2012-10-08

    We report a substantial increase in the heat resistance in a connector-type single-wall carbon nanotube (SWNT) saturable absorber by sealing SWNT/P3HT composite with siloxane. By applying the saturable absorber to a passively mode-locked Er fiber laser, we successfully demonstrated 280 fs, 31 mW pulse generation with a fivefold improvement in heat resistance.

  4. Assessment of Potential Capacity Increases at Combined Heat and Power Facilities Based on Available Corn Stover and Forest Logging Residues

    Directory of Open Access Journals (Sweden)

    Donald L. Grebner

    2013-08-01

    Full Text Available Combined Heat and Power (CHP production using renewable energy sources is gaining importance because of its flexibility and high-energy efficiency. Biomass materials, such as corn stover and forestry residues, are potential sources for renewable energy for CHP production. In Mississippi, approximately 4.0 MT dry tons of woody biomass is available annually for energy production. In this study, we collected and analyzed 10 years of corn stover data (2001–2010 and three years of forest logging residue data (1995, 1999, and 2002 in each county in Mississippi to determine the potential of these feed stocks for sustainable CHP energy production. We identified six counties, namely Amite, Copiah, Clarke, Wayne, Wilkinson and Rankin, that have forest logging residue feedstocks to sustain a CHP facility with a range of capacity between 8.0 and 9.8 MW. Using corn stover alone, Yazoo and Washington counties can produce 13.4 MW and 13.5 MW of energy, respectively. Considering both feedstocks and based on a conservative amount of 30% available forest logging residue and 33% corn stover, we found that 20 counties have adequate supply for a CHP facility with a capacity of 8.3 MW to 19.6 MW.

  5. PM-GCD - A combined IR-MW satellite technique for frequent retrieval of heavy precipitation: Application to the EU FLASH project

    Science.gov (United States)

    Casella, Daniele; Dietrich, Stefano; di Paola, Francesco; Formenton, Marco; Mugnai, Alberto; Sanò, Paolo

    2010-05-01

    Precipitation retrievals based on measurements from microwave (MW) radiometers onboard low-Earth-orbit (LEO) satellites can reach a high level of accuracy - and especially so, for deep convective precipitating systems. However, these observations do not provide a satisfactorily coverage of the rapid evolution of intense precipitating systems. As a result, the obtained precipitation retrievals are often of limited use for many important applications -- including support to authorities in activating flood alarms. To avoid this problem, several techniques have been developed that combine accurate MW estimates with frequent infrared (IR) observations from geosynchronous (GEO) satellites, such as the European Meteosat Second Generation (MSG). Within the European Union FP6 FLASH project, we have developed a new combined MW-IR technique for producing frequent precipitation retrievals from space (which we call PM-GCD technique). This technique uses passive-microwave (PM) retrievals in conjunction with the Global Convection Detection (GCD) technique that discriminates deep convective clouds within the GEO observations, based on the difference between the water vapor (6.2 μm ) and thermal-IR (10.8 μm ) channels. In essence, within the PM-GCD technique, deep convective areas are defined from MSG observations, then calibrated using MW-AMSU precipitation retrievals and finally propagated over time with a simple tracking algorithm. In this paper, we describe the PM-GCD technique and discuss the results of its application to a flood event that occurred on September 12-15, 2006 over the north-western Mediterranean coastal areas, and that has been selected for joint research by the EU FLASH and HYDRATE projects.

  6. Optimal Operation of Network-Connected Combined Heat and Powers for Customer Profit Maximization

    Directory of Open Access Journals (Sweden)

    Da Xie

    2016-06-01

    Full Text Available Network-connected combined heat and powers (CHPs, owned by a community, can export surplus heat and electricity to corresponding heat and electric networks after community loads are satisfied. This paper proposes a new optimization model for network-connected CHP operation. Both CHPs’ overall efficiency and heat to electricity ratio (HTER are assumed to vary with loading levels. Based on different energy flow scenarios where heat and electricity are exported to the network from the community or imported, four profit models are established accordingly. They reflect the different relationships between CHP energy supply and community load demand across time. A discrete optimization model is then developed to maximize the profit for the community. The models are derived from the intervals determined by the daily operation modes of CHP and real-time buying and selling prices of heat, electricity and natural gas. By demonstrating the proposed models on a 1 MW network-connected CHP, results show that the community profits are maximized in energy markets. Thus, the proposed optimization approach can help customers to devise optimal CHP operating strategies for maximizing benefits.

  7. A compactly integrated cooling system of a combination dual 1.5-MW HTS motors for electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Le, T. D.; Kim, J. H.; Hyeon, C. J.; Kim, H. M.; Kim, D. K. [Jeju National University, Jeju (Korea, Republic of); Kim, Y. S. [Shin Ansan University, Ansan (Korea, Republic of); Lee, J.; Park, Y. G.; Jeon, H. [Yonsei University, Seoul (Korea, Republic of); Quach, H. L. [Electronic and Telecommunication Engineering, Can Tho University of Technology, Can Tho (Viet Nam)

    2016-12-15

    The high temperature superconducting (HTS) contra-rotating propulsion (CRP) systems comprise two coaxial propellers sited on behind the other and rotate in opposite directions. They have the hydrodynamic advantage of recovering the slipstream rotational energy which would otherwise be lost to a conventional single-screw system. However, the cooling systems used for HTS CRP system need a high cooling power enough to maintain a low temperature of 2G HTS material operating at liquid neon (LNe) temperature (24.5 - 27 K). In this paper, a single thermo-syphon cooling approach using a Gifford-McMahon (G-M) cryo-cooler is presented. First, an optimal thermal design of a 1.5 MW HTS motor was conducted varying to different types of commercial 2G HTS tapes. Then, a mono-cryogenic cooling system for an integration of two 1.5 MW HTS motors will be designed and analyzed. Finally, the 3D finite element analysis (FEA) simulation of thermal characteristics was also performed.

  8. Measurement of gas species, temperatures, char burnout, and wall heat fluxes in a 200-MW{sub e} lignite-fired boiler at different loads

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhengqi; Jing, Jianping; Liu, Guangkui; Chen, Zhichao; Liu, Chunlong [School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001 (China)

    2010-04-15

    We measured various operational parameters of a 200-MW{sub e}, wall-fired, lignite utility boiler under different loads. The parameters measured were gas temperature, gas species concentration, char burnout, component release rates (C, H and N), furnace temperature, heat flux, and boiler efficiency. Cold air experiments of a single burner were conducted in the laboratory. A double swirl flow pulverized-coal burner has two ring recirculation zones that start in the secondary air region of the burner. With increasing secondary air flow, the air flow axial velocity increases, the maximum values for the radial velocity, tangential velocity, and turbulence intensity all increase, and there are slight increases in the air flow swirl intensity and the recirculation zone size. With increasing load gas, the temperature and CO concentration in the central region of burner decrease, while O{sub 2} concentration, NO{sub x} concentration, char burnout, and component release rates of C, H, and N increase. Pulverized-coal ignites farther into the burner, in the secondary air region. Gas temperature, O{sub 2} concentration, NO{sub x} concentration, char burnout and component release rates of C, H, and N all increase. Furthermore, CO concentration varies slightly and pulverized-coal ignites closer. In the side wall region, gas temperature, O{sub 2} concentration, and NO{sub x} concentration all increase, but CO concentration varies only slightly. In the bottom row burner region the furnace temperature and heat flux increase appreciably, but the increase become more obvious in the middle and top row burner regions and in the burnout region. Compared with a 120-MW{sub e} load, the mean NO{sub x} emission at the air preheater exits for 190-MW{sub e} load increases from 589.5 mg/m{sup 3} (O{sub 2} = 6%) to 794.6 mg/m{sup 3} (O{sub 2} = 6%), and the boiler efficiency increases from 90.73% to 92.45%. (author)

  9. Testing a residential fuel cell for combined heat and power

    National Research Council Canada - National Science Library

    Bell, M; Swinton, Michael C (Mike); Armstrong, Marianne M; Entchev, E; Gusdorf, J; Szadkowski, F

    2006-01-01

    ... the grid. This project demonstrated the performance of a residential FC combined heat and power (CHP) system, and examined residential CHP integration issues such as thermal storage, grid connection, and optimal FC size...

  10. Businesses Find Savings in Combined Heat and Power Systems

    Science.gov (United States)

    DALLAS - (Oct. 30, 2015) Businesses and organizations across the country are saving money and reducing their environmental footprint by using combined heat and power (CHP) technology in their buildings. These highly efficient systems simultaneously

  11. Micro-Combined Heat and Power Device Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NIST has developed a test facility for micro-combined heat and power (micro-CHP) devices to measure their performance over a range of different operating strategies...

  12. Retrofitting Combined Space and Water Heating Systems. Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernStar Building America Partnership, St. Paul, MN (United States); Bohac, D. [NorthernStar Building America Partnership, St. Paul, MN (United States); Huelman, P. [NorthernStar Building America Partnership, St. Paul, MN (United States); Olsen, R. [NorthernStar Building America Partnership, St. Paul, MN (United States); Hewett, M. [NorthernStar Building America Partnership, St. Paul, MN (United States)

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  13. Retrofitting Combined Space and Water Heating Systems: Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B.; Bohac, D.; Huelman, P.; Olson, R.; Hewitt, M.

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  14. Combined heat and power in a grain whisky distillery

    Energy Technology Data Exchange (ETDEWEB)

    1989-03-01

    The gas turbine based CHP system installed at Scottish Grain Distillers' Port Dundas distillery in Glasgow has been in beneficial operation since September 1985. It provides a surplus of electrical power and a supply of high grade energy in its exhaust gas, used directly in a dryer associated with the by-product animal feed plant, as well as for process steam generation. The project has demonstrated that a gas turbine can be used to supply a large quantity of high grade heat to process equipment normally requiring direct firing, whilst providing a reliable power supply meeting the requirements of the site, with a surplus available for export to the grid. While the particular set of circumstances at Port Dundas are unlikely to be encountered outside the distilling industry, opportunities exist for energy savings through gas turbine-based CHP installations in any continuous process industry where the site electrical load exceeds 2 MW and a suitable heat load of over 150 therms/hour exists in the form of direct process heating and/or steam generation (about 7 tonnes/hour). For sites burning gas or oil and in continuous production the payback priod can range from 2.5 to 4.5 years. (author).

  15. 300 MW 机组循环水余热-热泵回收系统的经济性分析%Economic Analysis of the Introduction of Absorption Heat Pump to Reclaim Waste-heat of Circulating Water In a 300 MW Unit

    Institute of Scientific and Technical Information of China (English)

    高建强; 王玉兰; 李寒冰; 王玉皓

    2015-01-01

    In the thermal power plant ,circulating cooling water contains abundant residual heat resources .Turbine-generator thermal efficiency is greatly improved by the introduction of absorption heat pump .This thesis takes thermal system energy efficiency distribution matrix equation ( EEDM ) to analyze and calculate a 300 MW unit which adopts the fifth segment extraction steam to drive the heat pump .The results show that cycle efficiency and heat energy utilization ratio increased respectively by 1.246% and 10.67%, because of the introduction of the heat pump technology , which can greatly save energy and reduce pollution .%热力发电厂循环冷却水蕴含较为丰富的低温余热资源,利用吸收式热泵技术将这一部分热量回收能够大幅度提高机组的热效率。采用热力系统能效分布矩阵方程(EEDM)对采用5段抽汽驱动热泵的某300MW机组进行分析计算,结果表明采用热泵技术使机组循环效率和热能利用率分别提高了1.246%和10.67%,能够很大程度的节约能源,减少污染。

  16. Combined ICR heating antenna for ion separation systems

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, A. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

    2011-01-15

    A combination of one- and two-wave antennas (one and two turns of conductors around a plasma cylinder, respectively) is proposed. This combined antenna localizes an RF field within itself. It is shown that spent nuclear fuel processing systems based on ICR heating of nuclear ash by such a combined antenna have high productivity. A theory of the RF field excitation in ICR ion separation systems is presented in a simple and compact form.

  17. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    OpenAIRE

    Bolonina Alona; Bolonins Genadijs; Blumberga Dagnija

    2014-01-01

    District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with redu...

  18. Combined Geothermal Potential of Subsurface Urban Heat Islands

    Science.gov (United States)

    Benz, Susanne; Bayer, Peter; Menberg, Kathrin; Blum, Philipp

    2016-04-01

    The subsurface urban heat island (SUHI) can be seen as a geothermal potential in form of elevated groundwater temperatures caused by anthropogenic heat fluxes into the subsurface. In this study, these fluxes are quantified for an annual timeframe in two German cities, Karlsruhe and Cologne. Our two-dimensional (2D) statistical analytical model determines the renewable and sustainable geothermal potential caused by six vertical anthropogenic heat fluxes into the subsurface: from (1) elevated ground surface temperatures, (2) basements, (3) sewage systems, (4) sewage leakage, (5) subway tunnels, and (6) district heating networks. The results show that at present 2.15 ± 1.42 PJ and 0.99 ± 0.32 PJ of heat are annually transported into the shallow groundwater of Karlsruhe and Cologne, respectively, due to anthropogenic heat fluxes into the subsurface. This is sufficient to sustainably cover 32% and 9% of the annual residential space heating demand of Karlsruhe and Cologne, respectively. However, most of the discussed anthropogenic fluxes into the subsurface are conductive heat fluxes and therefore dependent on the groundwater temperature itself. Accordingly, a decrease in groundwater temperature back to its natural (rural) state, achieved through the use of geothermal heat pumps, will increase these fluxes and with them the sustainable potential. Hence, we propose the introduction of a combined geothermal potential that maximizes the sustainability of urban shallow geothermal energy use and the efficiency of shallow geothermal systems by balancing groundwater temperature with anthropogenic heat fluxes into the subsurface. This will be a key element in the development of a demand-oriented, cost-efficient geothermal management tool with an additional focus on the sustainability of the urban heat sources.

  19. Combined heat and power economic dispatch by harmony search algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Vasebi, A.; Bathaee, S.M.T. [Power System Research Laboratory, Department of Electrical and Electronic Engineering, K.N.Toosi University of Technology, 322-Mirdamad Avenue West, 19697 Tehran (Iran); Fesanghary, M. [Department of Mechanical Engineering, Amirkabir University of Technology, 424-Hafez Avenue, Tehran (Iran)

    2007-12-15

    The optimal utilization of multiple combined heat and power (CHP) systems is a complicated problem that needs powerful methods to solve. This paper presents a harmony search (HS) algorithm to solve the combined heat and power economic dispatch (CHPED) problem. The HS algorithm is a recently developed meta-heuristic algorithm, and has been very successful in a wide variety of optimization problems. The method is illustrated using a test case taken from the literature as well as a new one proposed by authors. Numerical results reveal that the proposed algorithm can find better solutions when compared to conventional methods and is an efficient search algorithm for CHPED problem. (author)

  20. Chemical and physical properties of cyclone fly ash from the grate-fired boiler incinerating forest residues at a small municipal district heating plant (6MW).

    Science.gov (United States)

    Pöykiö, R; Rönkkömäki, H; Nurmesniemi, H; Perämäki, P; Popov, K; Välimäki, I; Tuomi, T

    2009-03-15

    In Finland, the new limit values for maximal allowable heavy metal concentrations for materials used as an earth construction agent came into force in July 2006. These limit values are applied if ash is utilized, e.g. in roads, cycling paths, pavements, car parks, sport fields, etc. In this study we have determined the most important chemical and physical properties of the cyclone fly ash originating from the grate-fired boiler incinerating forest residues (i.e. wood chips, sawdust and bark) at a small municipal district heating plant (6 MW), Northern Finland. This study clearly shows that elements are enriched in cyclone fly ash, since the total element concentrations in the cyclone fly ash were within 0.2-10 times higher than those in the bottom ash. The total concentrations of Cd (25 mg kg(-1); d.w.), Zn (3630 mg kg(-1); d.w.), Ba (4260 mg kg(-1); d.w.) and Hg (1.7 mg kg(-1); d.w.) exceeded the limit values, and therefore the cyclone fly ash cannot be used as an earth construction agent. According to the leached amounts of Cr (38 mg kg(-1); d.w.), Zn (51 mg kg(-1); d.w.) and sulphate (50,000 mg kg(-1); d.w.), the cyclone fly ash is classified as a hazardous waste, and it has to be deposited in a hazardous waste landfill.

  1. Waste heat recovery options in a large gas-turbine combined power plant

    Science.gov (United States)

    Upathumchard, Ularee

    This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste heat sources are combustion turbine (CT) room ventilation air and lubrication oil return from the power plant. The following options are being considered in this research: absorption chillers for cooling with working fluids Ammonia-Water and Water-Lithium Bromide (in comparison) and Organic Rankine Cycle (ORC) with working fluids R134a and R245fa. The absorption cycles are modeled in three different stages; single-effect, double-effect and half-effect. ORC models used are simple ORC as a baseline, ORC with internal regenerator, ORC two-phase flash expansion ORC and ORC with multiple heat sources. Thermodynamic models are generated and each system is simulated using Engineering Equation Solver (EES) to define the most suitable waste heat recovery options for the power plant. The result will be synthesized and evaluated with respect to exergy utilization efficiency referred as the Second Law effectiveness and net output capacity. Results of the models give recommendation to install a baseline ORC of R134a and a double-effect water-lithium bromide absorption chiller, driven by ventilation air from combustion turbine compartment. The two technologies yield reasonable economic payback periods of 4.6 years and 0.7 years, respectively. The fact that this selected power plant is in its early stage of operation allows both models to economically and effectively perform waste heat

  2. The Economic Analysis about the Bottom Ash Cooler Waste heat of 200 MW CFB Air Cooling Crew%200 MW CFB空冷机组冷渣器余热利用经济性分析

    Institute of Scientific and Technical Information of China (English)

    王林虎

    2015-01-01

    针对山西耀光煤电有限责任公司200 MW CFB空冷机组冷渣器改后的热量回收的现有系统,提出了2个新的方案.通过等效焓降法对不同负荷下的3个方案进行经济性分析,得出冷渣器与稻低加并联为最佳热量回收方案.

  3. Heat Transfer and Its Effect on Solidification in Combined Mould

    Institute of Scientific and Technical Information of China (English)

    QIU Sheng-tao; TAO Hong-biao; TANG Hong-wei; ZHANG Hui; ZHAO Pei

    2005-01-01

    The nucleation can be enhanced by decreasing the superheat of molten steel, thus reducing temperature gradient on the solidification front can retard the growth of columnar crystals and enlarge the equiaxed zone in continuous casting strand. The billets with equiaxed zone more than 90% were cast with a combined mould and the heatflux was measured. The heat transfer of the combined mould and traditional mould was compared. The results show that under same casting conditions, the temperature gradient on the solidification front in the combined mould is smaller than that in traditional mould at a distance within 0-150 mm from the meniscus.

  4. Measure Guideline: Combined Space and Water Heating Installation and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Bohac, D. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Huelman, P. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership

    2017-03-03

    Combined space and water heater (combi or combo) systems are defined by their dual functionality. Combi systems provide both space heating and water heating capabilities with a single heat source. This guideline will focus on the installation and operation of residential systems with forced air heating and domestic hot water (DHW) functionality. Past NorthernSTAR research has used a combi system to replace a natural gas forced air distribution system furnace and tank type water heater (Schoenbauer et al. 2012; Schoenbauer, Bohac, and McAlpine 2014). The combi systems consisted of a water heater or boiler heating plant teamed with a hydronic air handler that included an air handler, water coil, and water pump to circulate water between the heating plant and coil. The combi water heater or boiler had a separate circuit for DHW. Past projects focused on laboratory testing, field characterization, and control optimization of combi systems. Laboratory testing was done to fully characterize and test combi system components; field testing was completed to characterize the installed performance of combi systems; and control methodologies were analyzed to understand the potential of controls to simplify installation and design and to improve system efficiency and occupant comfort. This past work was relied upon on to create this measure guideline.

  5. Measure Guideline: Combined Space and Water Heating Installation and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, St. Paul, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, St. Paul, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, St. Paul, MN (United States)

    2017-03-01

    Combined space and water heater (combi or combo) systems are defined by their dual functionality. Combi systems provide both space heating and water heating capabilities with a single heat source. This guideline will focus on the installation and operation of residential systems with forced air heating and domestic hot water (DHW) functionality. Past NorthernSTAR research has used a combi system to replace a natural gas forced air distribution system furnace and tank type water heater (Schoenbauer et al. 2012; Schoenbauer, Bohac, and McAlpine 2014). The combi systems consisted of a water heater or boiler heating plant teamed with a hydronic air handler that included an air handler, water coil, and water pump to circulate water between the heating plant and coil. The combi water heater or boiler had a separate circuit for DHW. Past projects focused on laboratory testing, field characterization, and control optimization of combi systems. Laboratory testing was done to fully characterize and test combi system components; field testing was completed to characterize the installed performance of combi systems; and control methodologies were analyzed to understand the potential of controls to simplify installation and design and to improve system efficiency and occupant comfort. This past work was relied upon on to create this measure guideline.

  6. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    Directory of Open Access Journals (Sweden)

    Bolonina Alona

    2014-12-01

    Full Text Available District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with reduced district heating supply temperature. Conclusions on the benefits of new operation modes are introduced.

  7. Carbofuran degradation by the application of MW-assisted H₂O₂ process.

    Science.gov (United States)

    Remya, Neelancherry; Lin, Jih-Gaw

    2011-01-01

    Carbofuran removal performance of a microwave (MW)-assisted H₂O₂ system under different MW-power levels (300-900 W) was investigated. Batch experiments were conducted at 100 mg/L carbofuran concentration using a modified-MW reactor with 2450 MHz of fixed frequency. As a precursor, control experiments were carried out with H₂O₂ alone, MW alone and conventional heating (CH). A maximum carbofuran removal of 14 % was observed in both H₂O₂ alone and CH systems. On the other hand, only 2 % removal was observed in the MW alone system irrespective of the operation-mode, i.e. continuous or pulsed. The combination of MW and H₂O₂ produced 100 % carbofuran removal in all the MW-assisted experiments. The MW-assisted system operated under continuous-mode and at 750 W has showed rapid carbofuran degradation, i.e. 30 sec, with the highest first-order removal rate constant of 25.82/min. However, 97 % carbon oxygen demand (COD) removal was observed in the same system only after 30 min. On the other hand, 100 % carbofuran removal and 49 % COD removal were observed in the pulsed-mode MW-assisted H₂O₂ system after 10 and 30 min, respectively. Carbofuran mineralization in the system was evidenced by the formation of ammonium and nitrate, and carbofuran intermediates.

  8. Investigation of a heat storage for a solar heating system for combined space heating and domestic hot water supply for homeowner´s association "Bakken"

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1998-01-01

    A heat storage for a solar heating system for combined space heating and domestic hot water supply was tested in a laboratory test facility.The heat storage consist of a mantle tank with water for the heating system and of a hot water tank, which by means of thermosyphoning is heated by the water...... in the heating system. The heat storage was tested in a heat storage test facility. The most important characteristics of the heat storage were determined by means of the tests and recommendations for the design of the heat storage were given....

  9. Analyzing the possibility of constructing the air heating system for an integrated solid fuel gasification combined-cycle power plant

    Science.gov (United States)

    Mikula, V. A.; Ryzhkov, A. F.; Val'tsev, N. V.

    2015-11-01

    Combined-cycle power plants operating on solid fuel have presently been implemented only in demonstration projects. One of possible ways for improving such plants consists in making a shift to hybrid process circuits of integrated gasification combined-cycle plants with external firing of solid fuel. A high-temperature air heater serving to heat compressed air is a key element of the hybrid process circuit. The article describes application of a high-temperature recuperative metal air heater in the process circuit of an integrated gasification combined-cycle power plant (IGCC). The available experience with high-temperature air heating is considered, and possible air heater layout arrangements are analyzed along with domestically produced heat-resistant grades of steel suitable for manufacturing such air heater. An alternative (with respect to the traditional one) design is proposed, according to which solid fuel is fired in a noncooled furnace extension, followed by mixing the combustion products with recirculation gases, after which the mixture is fed to a convective air heater. The use of this design makes it possible to achieve considerably smaller capital outlays and operating costs. The data obtained from thermal and aerodynamic calculations of the high-temperature air heater with a thermal capacity of 258 MW for heating air to a temperature of up to 800°C for being used in the hybrid process circuit of a combined-cycle power plant are presented.

  10. Galerkin method for solving combined radiative and conductive heat transfer

    OpenAIRE

    Ghattassi, Mohamed; Roche, Jean Rodolphe; Asllanaj, Fatmir; Boutayeb, Mohamed

    2016-01-01

    International audience; This article deals with a numerical solution for combined radiation and conduction heat transfer in a grey absorbing and emitting medium applied to a two-dimensional domain using triangular meshes. The radiative transfer equation was solved using the high order Discontinuous Galerkin method with an upwind numerical flux. The energy equation was discretized using a high order finite element method. Stability and error analysis were performed for the Discontinuous Galerk...

  11. The Optimization of Draining System of Heating Network in 350MW Supercritical Heat Supplying Unit%350MW超临界供热机组热网疏水系统优化

    Institute of Scientific and Technical Information of China (English)

    王卫良; 李永生

    2013-01-01

    The draining methods of drainage water from heating network heater in 350MW supercritical unit have been discussed.The problems and disadvantages of methods like directly drained into deaerator,drained into deaerator after deironing in high temperature and drained into condenser after cooling were pointed out.Method of drained into the steam side of LP heater has been proposed,and the effects of tiny heat loss,no need for drawing off of drainage water during startup and deironing in high temperature,no reevaporation in condenser and steady backpressure could be met.A case of rated heating condition has been calculated,and the loss of heat rate is only 0.27%.%对350MW超临界供热机组热网加热器疏水不同处理方案进行对比分析,指出直接去除氧器、高温除铁后进入除氧器、降温处理后进入凝汽器等方案存在的问题,提出了改进型热网疏水系统,即直接进入5号低加疏水侧.改进后可实现无启动放水、无高温除铁、无凝汽器二次蒸发和背压升高等效果.以某350MW机组额定采暖抽汽工况为对象,改进后系统损耗仅为机组热耗的0.27%.

  12. Large Combined Heat and Power Plants for Sustainable Energy System

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Mathiesen, Brian Vad

    . CHP (combined heat and power) plants in Denmark will change their role from base load production to balancing the fluctuation in renewable energy supply, such as wind power and at the same time they have to change to renewable energy sources. Some solutions are already being planned by utilities...... in Denmark; conversion of pulverised fuel plants from coal to wood pellets and a circulating fluidised bed (CFB) plant for wood chips. From scientific research projects another solution is suggested as the most feasible; the combined cycle gas turbine (CCGT) plant. In this study a four scenarios...

  13. The new RETScreen model for combined heat and power

    Energy Technology Data Exchange (ETDEWEB)

    Ziegler, U. [Natural Resources Canada, Varennes, PQ (Canada). CANMET Energy Diversification Laboratory

    2004-07-01

    RETScreen{sup R} is unique renewable energy awareness, decision-support and capacity building computer program designed to evaluate the energy performance, cost and viability of potential renewable energy technologies (RETs). The program has recently included a combined heat and power (CHP) model which includes the energy analysis for reciprocating engines, gas turbines, gas turbine combined cycle, fuel cells, steam turbines, microturbines, and geothermal energy. It was developed at the RETScreen International Renewable Energy Decision Support Centre at CANMET (Canada Centre for Mineral and Energy Technology). The tool consists of a standardised and integrated renewable energy analysis software that can be used worldwide to evaluate the energy production, life-cycle costs and greenhouse gas emission reductions for various types of RETs, and then compare them with those of conventional energy sources. Global climate change mitigation depends on widespread use of RETs around the world to meet the commitments of the Kyoto Protocol for cleaner air. The use of this computer program can help reduce the cost of pre-feasibility studies by providing information to help make better decisions about the technical and economic viability of potential projects. The CHP model considers landfill gas, biomass, bagasse, biodiesel, hydrogen, natural gas, petroleum, coal and municipal wastes. The model can be used for heating only, power only, cooling only, combined heat and power, single or multiple buildings, district energy or industrial processes. 22 figs.

  14. Quality of shell eggs pasteurized with heat or heat-ozone combination during extended storage.

    Science.gov (United States)

    Perry, J J; Rodriguez-Saona, L E; Yousef, A E

    2011-09-01

    The physical quality and functionality of shell eggs, pasteurized with heat or a combination of heat and ozone, were assessed during eight weeks of storage at 4 or 25 °C. Shell eggs were treated as follows: (1) immersion heating that mimics commercial pasteurization processes (egg internal temperature of 56 ± 0.1 °C for 32 min), or (2) a newly developed combination process comprised of heating (56 ± 0.1 °C, internal, for 10 min) followed by gaseous ozone treatment. Eggs were tested for yolk index, Haugh units, albumen pH, albumen turbidity, and percent overrun. Additionally, albumen samples were assayed for lysozyme activity and free sulfhydryl group content, and were analyzed using differential scanning calorimetry and Fourier transform infrared (FTIR) spectroscopy. Both processed and unprocessed eggs maintained superior quality when stored at 4 °C, as opposed to 25 °C. Pasteurization, regardless of method, led to superior maintenance of Haugh units during storage but also increased albumen opacity and decreased albumen overrun. Detrimental effects on quality markers were more severe in heat-pasteurized eggs than those treated with the ozone-based process. Pasteurization of shell eggs by either process did not affect lysozyme activity or sulfhydryl group content. Changes in protein secondary structure, as indicated by FTIR analysis, suggest that the ozone-based process is less damaging to albumen proteins than is the heat-alone process. In conclusion, heat-ozone pasteurization, by virtue of its less severe heat treatment, yields a safe final product that more closely resembles untreated shell eggs. © 2011 Institute of Food Technologists®

  15. Fullerenes synthesis by combined resistive heating and arc discharge techniques.

    Science.gov (United States)

    Kyesmen, Pannan Isa; Onoja, Audu; Amah, Alexander Nwabueze

    2016-01-01

    The two main electrode techniques for fullerenes production; the direct arc technique and the resistive heating of graphite rod were employed in this work. One of the electrodes was resistively heated to high temperature and subjected to arc discharge along its length by the second graphite rod. Fullerenes solid were extracted from carbon soot samples collected from an installed arc discharge system using the solvent extraction method. The fullerenes solid obtained from carbon soot collected for 2 min of arc discharge run when one of the electrodes was resistively heated at different voltages all gave higher yields (maximum of 67 % higher, at 150 A arc current and 200 Torr chamber pressure) compared to when no resistive heating was carried out. Scanning electron microscopy and ultraviolet visible spectroscopy analysis carried out on all fullerenes solid indicated the presence of fullerenes. The enhancement of fullerenes production by combined resistive and direct arc techniques shows prospect for possible use at industrial level for large scale production.

  16. Investigation of HHFW and NBI Combined Heating in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    B.P. LeBlanc; R.E. Bell; S. Bernabei; T.M. Biewer; J.C. Hosea; J.R. Wilson

    2005-04-27

    A series of experiments was conducted to investigate the combined utilization of high-harmonics fast-wave (HHFW) and neutral-beam injection (NBI) auxiliary heating in National Spherical Torus Experiment (NSTX) plasmas. A modest increase of the total stored energy coincident with a near doubling of the neutron production rate is observed when NBI heating is added to HHFW in L-mode plasmas. An increase in the core electron temperature is also observed. On the other hand, essentially no stored energy augmentation nor neutron production rate enhancement is observed when applying HHFW during the ''H'' phase of NBI-driven H-mode plasmas. Spectroscopic measurements of the edge carbon line radiation indicate an unpredicted ion temperature increase, suggesting that edge effects are reducing the amount of HHFW power reaching the plasma core.

  17. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%-4.3% (20-40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes.

  18. WORKING PARK-FUEL CELL COMBINED HEAT AND POWER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Allan Jones

    2003-09-01

    This report covers the aims and objectives of the project which was to design, install and operate a fuel cell combined heat and power (CHP) system in Woking Park, the first fuel cell CHP system in the United Kingdom. The report also covers the benefits that were expected to accrue from the work in an understanding of the full technology procurement process (including planning, design, installation, operation and maintenance), the economic and environmental performance in comparison with both conventional UK fuel supply and conventional CHP and the commercial viability of fuel cell CHP energy supply in the new deregulated energy markets.

  19. Combined Heat and Power Market Potential for Opportunity Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Jones, David [Resource Dynamics Corporation, McLean, VA (United States); Lemar, Paul [Resource Dynamics Corporation, McLean, VA (United States

    2015-12-01

    This report estimates the potential for opportunity fuel combined heat and power (CHP) applications in the United States, and provides estimates for the technical and economic market potential compared to those included in an earlier report. An opportunity fuel is any type of fuel that is not widely used when compared to traditional fossil fuels. Opportunity fuels primarily consist of biomass fuels, industrial waste products and fossil fuel derivatives. These fuels have the potential to be an economically viable source of power generation in various CHP applications.

  20. Combined operation of two ground transmitters for enhanced ionospheric heating

    Science.gov (United States)

    Lee, M. C.; Groves, K. M.; Liao, C. P.; Rivas, D. R.; Kuo, S. P.

    1988-01-01

    The combined operation of a high or medium frequency ground transmitter and a VLF transmitter for enhanced ionospheric heating is examined. The high or medium frequency transmitter operating in a pulsed mode produce short-scale density striations that can render the nonlinear mode conversion of the subsequently launched VLF waves into lower hybrid waves. Also if the VLF waves are intense enough, they can excite meter-scale density striations and lower hybrid waves via parametric instabilities. The expected ionospheric effects of the system are discussed.

  1. Stochastic analysis of residential micro combined heat and power system

    DEFF Research Database (Denmark)

    Karami, H.; Sanjari, M. J.; Gooi, H. B.

    2017-01-01

    algorithm. The optimized scheduling of different energy resources is listed in an efficient look-up table for all time intervals. The effects of time of use and the battery efficiency and its size are investigated on the operating cost of the hybrid energy system. The results of this paper are expected......In this paper the combined heat and power functionality of a fuel-cell in a residential hybrid energy system, including a battery, is studied. The demand uncertainties are modeled by investigating the stochastic load behavior by applying Monte Carlo simulation. The colonial competitive algorithm...

  2. Standby Rates for Combined Heat and Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sedano, Richard [Regulatory Assistance Partnership; Selecky, James [Brubaker & Associates, Inc.; Iverson, Kathryn [Brubaker & Associates, Inc.; Al-Jabir, Ali [Brubaker & Associates, Inc.

    2014-02-01

    Improvements in technology, low natural gas prices, and more flexible and positive attitudes in government and utilities are making distributed generation more viable. With more distributed generation, notably combined heat and power, comes an increase in the importance of standby rates, the cost of services utilities provide when customer generation is not operating or is insufficient to meet full load. This work looks at existing utility standby tariffs in five states. It uses these existing rates and terms to showcase practices that demonstrate a sound application of regulatory principles and ones that do not. The paper also addresses areas for improvement in standby rates.

  3. Combined NMR moisture, temperature and pressure measurements during heating

    Directory of Open Access Journals (Sweden)

    Pel L.

    2013-09-01

    Full Text Available For model validation, quantitative measurements of the evolution of moisture, temperature, and pressure distributions in time are needed. For this purpose, we have developed an NMR setup to measure the moisture transport in heated building materials. The measured combined moisture content and temperature profiles give a unique insight in the moisture transport and dehydration kinetics inside concrete during fire. These measurements give the first quantitative proof for the build-up of a moisture peak due to the vapor pressure build-up. In this study we have also combined for the first time the measurement of the moisture and temperature profiles with the measurement of the pressure at one position, which show that the pressure build up is directly related to the moisture profiles.

  4. Investigation of the flow, combustion, heat-transfer and emissions from a 609MW utility tangentially fired pulverized-coal boiler

    DEFF Research Database (Denmark)

    Yin, Chungen; Caillat, Sébastien; Harion, Jean-Luc.;

    2002-01-01

    A numerical approach is given to investigate the performance of a 609 MW tangentially fired pulverized-coal boiler, with emphasis on formation mechanism of gas flow deviation and uneven wall temperature in crossover pass and on NOx emission. To achieve this purpose and obtain a reliable solution...... are reliable. These conclusions can be used to guide the design and operation of boilers of similar types....

  5. Design of the 1.5 MW, 30-96 MHz ultra-wideband 3 dB high power hybrid coupler for Ion Cyclotron Resonance Frequency (ICRF) heating in fusion grade reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Rana Pratap, E-mail: ranayadav97@gmail.com; Kumar, Sunil; Kulkarni, S. V. [Thapar University, Patiala, Punjab 147004, India and Institute for Plasma Research, Gandhinagar 382428 (India)

    2016-01-15

    Design and developmental procedure of strip-line based 1.5 MW, 30-96 MHz, ultra-wideband high power 3 dB hybrid coupler has been presented and its applicability in ion cyclotron resonance heating (ICRH) in tokamak is discussed. For the high power handling capability, spacing between conductors and ground need to very high. Hence other structural parameters like strip-width, strip thickness coupling gap, and junction also become large which can be gone upto optimum limit where various constrains like fabrication tolerance, discontinuities, and excitation of higher TE and TM modes become prominent and significantly deteriorates the desired parameters of the coupled lines system. In designed hybrid coupler, two 8.34 dB coupled lines are connected in tandem to get desired coupling of 3 dB and air is used as dielectric. The spacing between ground and conductors are taken as 0.164 m for 1.5 MW power handling capability. To have the desired spacing, each of 8.34 dB segments are designed with inner dimension of 3.6 × 1.0 × 40 cm where constraints have been significantly realized, compensated, and applied in designing of 1.5 MW hybrid coupler and presented in paper.

  6. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%–4.3% (20–40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes. The full modulation control showed additional savings over set point control (in high-load homes almost doubling the savings: 4%–5% over the no-control case). At the time of installation the reset control can be implemented for $200–$400, which would provide paybacks of 6–25 years for low-load houses and 3–15 years for high-load houses. Full modulation implementation costs would be similar to the outdoor reset and would provide paybacks of 5-½–20 years for low-load houses and 2-½–10 years for high-load houses.

  7. Combined heat transfer and kinetic models to predict cooking loss during heat treatment of beef meat.

    Science.gov (United States)

    Kondjoyan, Alain; Oillic, Samuel; Portanguen, Stéphane; Gros, Jean-Bernard

    2013-10-01

    A heat transfer model was used to simulate the temperature in 3 dimensions inside the meat. This model was combined with a first-order kinetic models to predict cooking losses. Identification of the parameters of the kinetic models and first validations were performed in a water bath. Afterwards, the performance of the combined model was determined in a fan-assisted oven under different air/steam conditions. Accurate knowledge of the heat transfer coefficient values and consideration of the retraction of the meat pieces are needed for the prediction of meat temperature. This is important since the temperature at the center of the product is often used to determine the cooking time. The combined model was also able to predict cooking losses from meat pieces of different sizes and subjected to different air/steam conditions. It was found that under the studied conditions, most of the water loss comes from the juice expelled by protein denaturation and contraction and not from evaporation.

  8. Temporary heat storage by using combined heat and power in supplementary lighted greenhouses Proceedings of the Third International Symposium on Artificial Lighting in Horticulture

    NARCIS (Netherlands)

    Huijs, J.P.G.

    1997-01-01

    Because of better utilization possibilities of the produced heat, decentrally located combined heat and power installations achieve a higher energetic efficiency than producing heat and power separately. However, efficiency depends considerably on synchronism of heat and electricity demand. Using a

  9. Combined radiative and natural or forced convective heat transfer between parallel vertical plates with two-dimensional discrete heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, T.W.

    1988-01-01

    This study numerically analyzes combined radiative and natural or forced convective heat transfer between vertical parallel plates with two-dimensional discrete heat sources. The numerical method was verified by comparing its results with other published experimental data and the agreement was excellent. It is shown that radiative heat transfer is a significant and useful mode of heat transfer in combination with both natural and forced convection in this situation and cannot be neglected. Radiative heat transfer accounted for 50-60% or more of the total heat transfer in some cases, and usually approximately 30-35% on the top of a discrete heat source. This fact can be used to advantage in the thermal design of electronic circuit boards.

  10. Combined effects of tectonic and landslide-generated Tsunami Runup at Seward, Alaska during the Mw 9.2 1964 earthquake

    Science.gov (United States)

    Suleimani, E.; Nicolsky, D.J.; Haeussler, P.J.; Hansen, R.

    2011-01-01

    We apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of Resurrection Bay and the town of Seward by the 1964 Alaska tsunami. Seward was hit by both tectonic and landslide-generated tsunami waves during the Mw 9.2 1964 mega thrust earthquake. The earthquake triggered a series of submarine mass failures around the fjord, which resulted in land sliding of part of the coastline into the water, along with the loss of the port facilities. These submarine mass failures generated local waves in the bay within 5 min of the beginning of strong ground motion. Recent studies estimate the total volume of underwater slide material that moved in Resurrection Bay to be about 211 million m3 (Haeussler et al. in Submarine mass movements and their consequences, pp 269-278, 2007). The first tectonic tsunami wave arrived in Resurrection Bay about 30 min after the main shock and was about the same height as the local landslide-generated waves. Our previous numerical study, which focused only on the local land slide generated waves in Resurrection Bay, demonstrated that they were produced by a number of different slope failures, and estimated relative contributions of different submarine slide complexes into tsunami amplitudes (Suleimani et al. in Pure Appl Geophys 166:131-152, 2009). This work extends the previous study by calculating tsunami inundation in Resurrection Bay caused by the combined impact of landslide-generated waves and the tectonic tsunami, and comparing the composite inundation area with observations. To simulate landslide tsunami runup in Seward, we use a viscous slide model of Jiang and LeBlond (J Phys Oceanogr 24(3):559-572, 1994) coupled with nonlinear shallow water equations. The input data set includes a high resolution multibeam bathymetry and LIDAR topography grid of Resurrection Bay, and an initial thickness of slide material based on pre- and post-earthquake bathymetry difference maps. For

  11. Combined vapor compression/absorption heat pump cycles for engine-driven heat pumps

    Science.gov (United States)

    Radermacher, Reinhard; Herold, Keith E.; Howe, Lawrence A.

    1988-12-01

    The performance of three combined absorption/vapor compression cycles for gas-fired internal combustion engine driven heat pumps was theoretically assessed. Two cycles were selected for the preliminary design of breadboard systems using only off-the-shelf components. The first cycle, based on the working pair ammonia/water, is termed the simple-cycle. The second cycle, based on the working pair lithium-bromide/water, is termed the compressor enhanced double-effect chiller. Both cycles are found to be technically feasible. The coefficient of performance and the capacity are increased by up to 21 percent for cooling in the first case (compressor efficiency of 0.7) and by up to 14 percent in the second (compressor efficiency of 0.5). Both were compared against the engine drive R22 vapor compression heat pump. The performance of actual machinery for both cycles is, in the current design, hampered by the fact that the desired oil-free compressors have poor isentropic efficiencies. Oil lubricated compressors together with very effective oil separators would improve the performance of the combined LiBr/water cycle to 23 percent.

  12. Small-Scale Combined Heat and Power Plants Using Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Salomon-Popa, Marianne [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-11-01

    In this time period where energy supply and climate change are of special concern, biomass-based fuels have attracted much interest due to their plentiful supply and favorable environmental characteristics (if properly managed). The effective capture and continued sustainability of this renewable resource requires a new generation of biomass power plants with high fuel energy conversion. At the same time, deregulation of the electricity market offers new opportunities for small-scale power plants in a decentralized scheme. These two important factors have opened up possibilities for small-scale combined heat and power (CHP) plants based on biofuels. The objective of this pre-study is to assess the possibilities and technical limitations for increased efficiency and energy utilization of biofuels in small size plants (approximately 10 MWe or lower). Various energy conversion technologies are considered and proven concepts for large-scale fossil fuel plants are an especially important area. An analysis has been made to identify the problems, technical limitations and different possibilities as recognized in the literature. Beyond published results, a qualitative survey was conducted to gain first-hand, current knowledge from experts in the field. At best, the survey results together with the results of personal interviews and a workshop on the role of small-scale plants in distributed generation will serve a guideline for future project directions and ideas. Conventional and novel technologies are included in the survey such as Stirling engines, combustion engines, gas turbines, steam turbines, steam motors, fuel cells and other novel technologies/cycles for biofuels. State-of-the-art heat and power plants will be identified to clarify of the advantages and disadvantages as well as possible obstacles for their implementation.

  13. Final Report: Assessment of Combined Heat and Power Premium Power Applications in California

    Energy Technology Data Exchange (ETDEWEB)

    Norwood, Zack; Lipman, Tim; Marnay, Chris; Kammen, Dan

    2008-09-30

    This report analyzes the current economic and environmental performance of combined heat and power (CHP) systems in power interruption intolerant commercial facilities. Through a series of three case studies, key trade-offs are analyzed with regard to the provision of black-out ridethrough capability with the CHP systems and the resutling ability to avoid the need for at least some diesel backup generator capacity located at the case study sites. Each of the selected sites currently have a CHP or combined heating, cooling, and power (CCHP) system in addition to diesel backup generators. In all cases the CHP/CCHP system have a small fraction of the electrical capacity of the diesel generators. Although none of the selected sites currently have the ability to run the CHP systems as emergency backup power, all could be retrofitted to provide this blackout ride-through capability, and new CHP systems can be installed with this capability. The following three sites/systems were used for this analysis: (1) Sierra Nevada Brewery - Using 1MW of installed Molten Carbonate Fuel Cells operating on a combination of digestor gas (from the beer brewing process) and natural gas, this facility can produce electricty and heat for the brewery and attached bottling plant. The major thermal load on-site is to keep the brewing tanks at appropriate temperatures. (2) NetApp Data Center - Using 1.125 MW of Hess Microgen natural gas fired reciprocating engine-generators, with exhaust gas and jacket water heat recovery attached to over 300 tons of of adsorption chillers, this combined cooling and power system provides electricity and cooling to a data center with a 1,200 kW peak electrical load. (3) Kaiser Permanente Hayward Hospital - With 180kW of Tecogen natural gas fired reciprocating engine-generators this CHP system generates steam for space heating, and hot water for a city hospital. For all sites, similar assumptions are made about the economic and technological constraints of the

  14. IMPROVED MANUFACTURING CANNED "COMPOTE CHERRY" USING COMBINED HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    A. F. Demirova

    2013-01-01

    Full Text Available The results of studies on the development of new modes of heat sterilization compote cherry using stepwise heating in a stream of hot air and hot water dushevaniem air cooled rotating container. Revealed that the modes provide commercial sterility of finished products, reducing the length of the heat treatment and the quality of the finished product. Are some of the modes of heat sterilization step of cherry compote in a stream of heated air and water dushevaniem air-cooled rotating container.

  15. Thermodynamic characteristics of a 200 MW unit with high back pressure circulating water heating%200 MW高背压循环水供热机组热力特性研究

    Institute of Scientific and Technical Information of China (English)

    江浩; 黄嘉驷; 王浩

    2015-01-01

    After retrofitting on high back pressure circulating water heating for a 200 MW unit,thermodynamic cal-culation was performed.The results show that,the heat net circulating water quantity and steam extraction amount (for heat supply)has little effects unit parameters such as heat consumption rate,unit output,heat load and circu-lating water outlet temperature.Under each working condition,the fuel utilization coefficient can reach about 90%, implying the energy comprehensive utilization effect is great.However,the unit back pressure is greatly affected by the heat net circulating water quantity and steam extraction amount.Moreover,the unit's operation regulating flexi-bility got poor and the retrofitting work capacity is pretty huge.The rotor changing time must be carefully selected after the retrofitting,and the units with very small heat load are not suitable for transformation.Due to small out-put of the 200 MW unit's low pressure (LP)cylinder,it suggests that the LP cylinder be split to reduce the modifi-cation range and simplify the steps.%通过对200 MW机组高背压循环水供热改造后的系统进行热力计算分析发现:热网循环水流量及采暖抽汽流量的变化对机组热耗率、出力、对外热负荷、循环水出水温度等参数的影响相对较小,各种运行工况下燃料利用系数均可达到90%左右,能源综合利用效果好;但对机组背压的影响较大,机组运行调整灵活性差,改造工作量大,改造后需把握好更换转子时机,对外供热热负荷较小的机组不宜实施改造;200 MW机组改造后低压缸做功量小,建议采用低压缸解列方案,以缩小改造范围和难度。

  16. Use of the available energy in the re-gasification process of liquefied natural gas by coupling combined heat and power cycles

    Energy Technology Data Exchange (ETDEWEB)

    Sgarbi, P.V.; Schmeda Lopez, D.R.; Indrusiak, M.L.S.; Schneider, P. Smith [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. of Mechanical Engineering], Emails: guetuso@gmail.com, diego.schmeda@ufrgs.br, sperbindrusiak@via-rs.net, pss@mecanica.ufrgs.br

    2009-07-01

    This work evaluates the possibilities of taking advantage of the heat transferred in the re-gasification process of liquid natural gas (LNG). It is proposed the coupling of a Brayton-Rankine combined heat and power plant (CHP) to a LNG re-gasification plant in order to use the heat involved in this process as cold source for the CHP plant. For comparison, the same CHP is simulated exchanging heat with a reference environment. An analysis is performed assuming that the amount of natural gas fed to the Brayton sub-cycle combustion chamber is equal for both cases. The CHP coupled to the re-gasification plant present a net power generation of 22.7 MW and the efficiency is 45.5%. It represents a gain of 2.98 MW in the power generation and 15% in the cycle efficiency, when compared to the reference cycle. The exergetic efficiency with this proposal is 49.3%, which is 9% higher than the reference cycle. (author)

  17. Improved Differential Evolution for Combined Heat and Power Economic Dispatch

    Science.gov (United States)

    Jena, C.; Basu, M.; Panigrahi, C. K.

    2016-04-01

    This paper presents an improved differential evolution to solve non-smooth non-convex combined heat and power economic dispatch (CHPED) problem. Valve-point loading and prohibited operating zones of conventional thermal generators are taken into account. Differential evolution (DE) exploits the differences of randomly sampled pairs of objective vectors for its mutation process. Consequently the variation between vectors will outfit the objective function toward the optimization process and therefore provides efficient global optimization capability. However, although DE is shown to be precise, fast as well as robust, its search efficiency will be impaired during solution process with fast descending diversity of population. This paper proposes Gaussian random variable instead of scaling factor which improves search efficiency. The effectiveness of the proposed method has been verified on four test systems. The results of the proposed approach are compared with those obtained by other evolutionary methods. It is found that the proposed improved differential evolution based approach is able to provide better solution.

  18. Absorption chillers integration in a combined heat and power plant

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, J. C.; Fernandez, F.; Castells, F. [Barcelona Univ., Tarragona (Spain). Dept. d`Enginyeria Quimica i Bioqumica

    1996-11-01

    Inclusion of an absorption cycle within a combined heat and power plant (CHP) was evaluated. To determine the most suitable configuration of the energy network generation system and absorption chiller, a simulation and optimization model was constructed. To validate the optimization model, a case study using actual data from existing operating plants has been used. In the case described the cooling facilities from the absorption cycle were used to lower the inlet temperature to the compressor of the gas turbine to improve the overall plant efficiency. Waste steam from the steam network was used in the generator of the absorption chiller. A reduction in steam wastes, and an improvement in overall plant efficiency was observed. A simulation model of a single effect absorption chiller, using water-lithium bromide as the working fluid pair, was used to validate the methodology. Results showed that the benefits of integrating the absorption refrigeration cycle (ARC) depends directly on the refrigeration demand, and on the benefit produced by the waste steam recovered. The increase in power generation, allowing a reduction in primary energy consumption, showed a slight economic advantage over the conventional compression cycle. 13 refs., 7. tabs., 6 figs.

  19. Alstom 6 MW; Alstom 6 MW

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-01

    Till to now, Alstom Deutschland AG has sold wind power plants via the Spanish subsidiary Ecotecnia: onshore plants with a classical concept and up to 3 MW. With all the competence of an energy and technology concept, Alstrom now introduces a large offshore plant: without gears and with PM generator. The main components which cannot be produced in the Alstom group are to be bought via development co-operations of the market leaders LM Wind Power Group (Kolding, Denmark) and Converteam GmbH (Berlin, Federal Republic of Germany).

  20. Performance characteristics of a combination solar photovoltaic heat engine energy converter

    Science.gov (United States)

    Chubb, Donald L.

    1987-01-01

    A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

  1. Preliminary Analysis on Heat Removal Capacity of Passive Air-Water Combined Cooling Heat Exchanger Using MARS

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung-Sin; Jeon, Seong-Su; Hong, Soon-Joon [FNC Tech, Yongin (Korea, Republic of); Bae, Sung-Won; Kwon, Tae-Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Current design requirement for working time of PAFS heat exchanger is about 8 hours. Thus, it is not satisfied with the required cooling capability for the long term SBO(Station Black-Out) situation that is required to over 72 hours cooling. Therefore PAFS is needed to change of design for 72 hours cooling. In order to acquirement of long terms cooling using PAFS, heat exchanger tube has to be submerged in water tank for long time. However, water in the tank is evaporated by transferred heat from heat exchanger tubes, so water level is gradually lowered as time goes on. The heat removal capacity of air cooling heat exchanger is core parameter that is used for decision of applicability on passive air-water combined cooling system using PAFS in long term cooling. In this study, the development of MARS input model and plant accident analysis are performed for the prediction of the heat removal capacity of air cooling heat exchanger. From analysis result, it is known that inflow air velocity is the decisive factor of the heat removal capacity and predicted air velocity is lower than required air velocity. But present heat transfer model and predicted air velocity have uncertainty. So, if changed design of PAFS that has over 4.6 kW heat removal capacity in each tube, this type heat exchanger can be applied to long term cooling of the nuclear power plant.

  2. Preparation and characterizations of heat storage material combining porous metal with molten salt

    Institute of Scientific and Technical Information of China (English)

    王华; 何方; 戴永年; 胡建杭

    2003-01-01

    A new type of heat storage materials combining high temperature molten salts phases change latent heat thermal storage materials, PCM with porous metals sensible heat thermal storage materials was developed. The process was expressed as following: firstly, it is necessary to heat up the molten salts phases change materials to molten; and then the porous metals are put into the molten bath; after being held for 1-3 h, the composite heat thermal storage materials lumps are taken out of the molten bath and cooled to atmospheric temperature; the last step is to electrodeposit a layer metal coat on the surface of the material lumps. The new type of heat storage material integrates the advantages of both solid sensible heat thermal storage materials and high temperature phases change latent heat thermal storage materials. The metal-base heat storage materials enjoy some favorable characteristics such as higher heat charge-discharge rate, higher heat storage density and better mechanical strength.

  3. Energy Optimization for Transcritical CO2 Heat Pump for Combined Heating and Cooling and Thermal Storage Applications

    DEFF Research Database (Denmark)

    Do Carmo, Carolina Madeira Ramos; Blarke, Morten; Yazawa, Kazuaki

    2012-01-01

    A transcritical heat pump (THP) cycle using carbon dioxide (CO2) as the refrigerant is known to feature an excellent coefficient of performance (COP) as a thermodynamic system. Using this feature, we are designing and building a system that combines a water-to-water CO2 heat pump with both hot an...

  4. local alternative sources for cogeneration combined heat and power system

    Science.gov (United States)

    Agll, Abdulhakim Amer

    Global demand for energy continues to grow while countries around the globe race to reduce their reliance on fossil fuels and greenhouse gas emissions by implementing policy measures and advancing technology. Sustainability has become an important issue in transportation and infrastructure development projects. While several agencies are trying to incorporate a range of sustainability measures in their goals and missions, only a few planning agencies have been able to implement these policies and they are far from perfect. The low rate of success in implementing sustainable policies is primarily due to incomplete understanding of the system and the interaction between various elements of the system. The conventional planning efforts focuses mainly on performance measures pertaining to the system and its impact on the environment but seldom on the social and economic impacts. The objective of this study is to use clean and alternative energy can be produced from many sources, and even use existing materials for energy generation. One such pathway is using wastewater, animal and organic waste, or landfills to create biogas for energy production. There are three tasks for this study. In topic one evaluated the energy saving that produced from combined hydrogen, heat, and power and mitigate greenhouse gas emissions by using local sustainable energy at the Missouri S&T campus to reduce energy consumption and fossil fuel usage. Second topic aimed to estimate energy recovery and power generation from alternative energy source by using Rankin steam cycle from municipal solid waste at Benghazi-Libya. And the last task is in progress. The results for topics one and two have been presented.

  5. Commissioning results of the 0.5 MW/68 GHz/1.0 s gyrotron on HL-2A electron cyclotron resonance heating system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, He, E-mail: wangh@swip.ac.cn; Rao, Jun; Huang, Mei; Zhou, Jun; Wang, Chao; Kang, Zihua; Wang, Mingwei; Feng, Kun; Chen, Gangyu; Lu, Bo; Wang, Jieqiong

    2015-12-15

    Highlights: • A test stand for the test of gyrotron is introduced. • Test results show that the output power of gyrotron has a close relation to the high voltage, magnet current and heater power. • The measurement method of operation frequency and output power of gyrotron is introduced. - Abstract: To obtain the optimum operation status of gyrotrons, it is necessary to commissioning the gyrotrons before EC wave injected into plasma for ECRH system on HL-2A tokamak. A test stand has been set up for conditioning the 0.5 MW/68 GHz/1.0 s gyrotrons. The specific test results of gyrotrons are described and discussed in this paper, which include measuring the beam profile by using burn paper at the outlet of MOU and calorimetric dummy load, testing the maximum output power and pulse width on dummy load and getting the dependence between output power and magnetic field current, filament power and high voltage powers. Meanwhile, the operation frequency of gyrotron is also measured in the test.

  6. Experimental study on heat transfer enhancement of a helically baffled heat exchanger combined with three-dimensional finned tubes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Zhnegguo; Xu Tao; Fang Xiaoming [South China University of Technology, Guangzhou (China). Ministry of Education

    2004-10-01

    Heat transfer and pressure drop of helically baffled heat exchanger combined with petal-shaped finned tubes for oil (ISO VG-32) cooling with water as coolant was experimentally studied. The tube side heat transfer coefficient was obtained by a modified Wilson plot technique. Results were presented as plots of the shell side heat transfer coefficient based on the actual outside surface area of tube bundle and pressure drop against volumetric flow rate of oil. Under experimental conditions, the maximum shell side heat transfer coefficient is 2265 W/m{sup 2} K, the corresponding shell side pressure drop is 91 kPa. The preliminary heat transfer enhancement mechanisms were discussed for oil flow helically on outside surface of petal-shaped finned tubes. (author)

  7. Measure Guideline. Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, Armin [Building Science Corporation Industry Team (BSC), Somerville, MA (United States)

    2012-08-01

    This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

  8. Measure Guideline: Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.

    2012-08-01

    This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

  9. Indoor temperatures for calculating room heat loss and heating capacity of radiant heating systems combined with mechanical ventilation systems

    DEFF Research Database (Denmark)

    Wu, Xiaozhou; Olesen, Bjarne W.; Fang, Lei;

    2016-01-01

    system were determined according to the principle of heat transfer. A model to predict indoor temperatures in the room was proposed, and it was determined that the predicted indoor temperatures agreed well with the measured data. Qualitative analyses of the effects of heated surface temperature and air...... change rates on the indoor temperatures were performed using the proposed model. When heated surface temperatures and air change rates were from 21.0 to 29.0 degrees C and from 0.5 to 4.0 h-1, the indoor temperatures for calculating the transmission heat loss and ventilation heat loss were between 20.......8% for calculating the transmission heat loss and ventilation heat loss, respectively, and between 16.0% and 17.4% for calculating the heating capacity of the hybrid system. Due to large relative calculation errors, it is necessary to consider the effect of heated surface and cool supply air on indoor temperatures...

  10. Encouraging Combined Heat and Power in California Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Groissbock, Markus [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cardoso, Goncalo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Muller, Andreas [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lai, Judy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-02-01

    Governor Brown’s research priorities include an additional 6.5 GW of combined heat and power (CHP) by 2030. As of 2009, roughly 0.25 GW of small natural gas and biogas fired CHP is documented by the Self-Generation Incentive Program (SGIP) database. The SGIP is set to expire, and the anticipated grid de-carbonization based on the development of 20 GW of renewable energy will influence the CHP adoption. Thus, an integrated optimization approach for this analysis was chosen that allows optimizing the adoption of distributed energy resources (DER) such as photovoltaics (PV), CHP, storage technologies, etc. in the California commercial sector from the building owners’ perspective. To solve this DER adoption problem the Distributed Energy Resources Customer Adoption Model (DER-CAM), developed by the Lawrence Berkeley National Laboratory and used extensively to address the problem of optimally investing and scheduling DER under multiple settings, has been used. The application of CHP at large industrial sites is well known, and much of its potential is already being realized. Conversely, commercial sector CHP, especially those above 50 to 100 kW peak electricity load, is widely overlooked. In order to analyze the role of DER in CO2 reduction, 147 representative sites in different climate zones were selected from the California Commercial End Use Survey (CEUS). About 8000 individual optimization runs, with different assumptions for the electric tariffs, natural gas costs, marginal grid CO2 emissions, and nitrogen oxide treatment costs, SGIP, fuel cell lifetime, fuel cell efficiency, PV installation costs, and payback periods for investments have been performed. The most optimistic CHP potential contribution in this sector in 2020 will be 2.7 GW. However, this result requires a SGIP in 2020, 46% average electric efficiency for fuel cells, a payback period for investments of 10 years, and a CO2 focused approach of the building owners. In

  11. Wave Dragon MW

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Frigaard, Peter

    Wave Dragon is a wave energy converter of the overtopping type. The device has been thoroughly tested on a 1:51.8 scale model in wave laboratories and a 1:4.5 scale model deployed in Nissum Bredning, a large inland waterway in Denmark. Based on the experience gained a full scale, multi MW prototype...

  12. Wave Dragon MW

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Frigaard, Peter

    Wave Dragon is a wave energy converter of the overtopping type. The device has been thoroughly tested on a 1:51.8 scale model in wave laboratories and a 1:4.5 scale model deployed in Nissum Bredning, a large inland waterway in Denmark. Based on the experience gained a full scale, multi MW prototype...

  13. Optimal Operation of Combined Heat and Power System Based on Forecasted Energy Prices in Real-Time Markets

    Directory of Open Access Journals (Sweden)

    Chenghong Gu

    2015-12-01

    Full Text Available This paper develops a discrete operation optimization model for combined heat and powers (CHPs in deregulated energy markets to maximize owners’ profits, where energy price forecasting is included. First, a single input and multi-output (SIMO model for typical CHPs is established, considering the varying ratio between heat and electricity outputs at different loading levels. Then, the energy prices are forecasted with a gray forecasting model and revised in real-time based on the actual prices by using the least squares method. At last, a discrete optimization model and corresponding dynamic programming algorithm are developed to design the optimal operation strategies for CHPs in real-time. Based on the forecasted prices, the potential operating strategy which may produce the maximum profits is pre-developed. Dynamic modification is then conducted to adjust the pre-developed operating strategy after the actual prices are known. The proposed method is implemented on a 1 MW CHP on a typical day. Results show the optimized profits comply well with those derived from real-time prices after considering dynamic modification process.

  14. Heat of fusion storage systems for combined solar systems in low energy buildings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Furbo, Simon

    2004-01-01

    Solar heating systems for combined domestic hot water and space heating has a large potential especially in low energy houses where it is possible to take full advantage of low temperature heating systems. If a building integrated heating system is used – e.g. floor heating - the supply temperature...... (and the the return temperature) would only be a few degrees above room temperature due to the very low heating demand and the large heat transfer surface area. One of the objectives in a newly started IEA Task 32 project is to investigate and develop improved thermal storages for combined solar...... systems through further improvement of water based storages and in parallel to investigate the potential of using storage designs with phase change materials, PCM. The advantage of phase change materials is that large amounts of energy can be stored without temperature increase when the material is going...

  15. Solar energy and heat pumps: evaluation of combined systems for heating and cooling of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.W.; Catan, M.A.; Le Doux, P.

    1982-09-01

    An analysis of a broad range of solar assisted heat pump systems was carried out. Systems were divided into three categories on the basis of whether ground coupling was included in the system and, if so, whether solar energy was stored in the ground or used in some other way. In the category of non-ground-coupled systems, an advanced air-source heat pump concept designed to improve capacity and coefficient of performance at low source temperatures was used as the basis for a dual source heat pump. For ground coupled systems which do not store solar heat in the ground, three options were considered: use of simple passive techniques to reduce the effective heating load; use of photovoltaics to drive the heat pump compressor; and use of active solar components as a source to the heat pump, for direct space heating, or for domestic hot water only. For systems which do store solar energy in the ground, the minimum size for efficient thermal carryover from summer to winter was determined to be a system capable of serving approx. 100 houses. Use of a fuel-fired heat pump is also an advantage in these larger systems. Economic analyses were based on a maximum allowable payback of 8 years for residential systems. For the large-scale system, a simplified 10-year life-cycle costing was employed.

  16. Large combined heat and power plants in sustainable energy systems

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Mathiesen, Brian Vad

    2015-01-01

    resources as efficiently as possible. Using the advanced energy systems analysis tool EnergyPLAN and Denmark as a case, this analysis defines which of the three assessed types of CHP plants connected to district heating systems is most feasible in terms of total socioeconomic costs and biomass consumption...

  17. Energy Optimization for Transcritical CO2 Heat Pump for Combined Heating and Cooling and Thermal Storage Applications

    DEFF Research Database (Denmark)

    Do Carmo, Carolina Madeira Ramos; Blarke, Morten; Yazawa, Kazuaki

    2012-01-01

    A transcritical heat pump (THP) cycle using carbon dioxide (CO2) as the refrigerant is known to feature an excellent coefficient of performance (COP) as a thermodynamic system. Using this feature, we are designing and building a system that combines a water-to-water CO2 heat pump with both hot...... and cold thermal storages know as Thermal Battery (TB) (Blarke, 2012). Smart and effective use of intermittent renewable energy resources (for example solar and wind power) is obtained supplying water heating (>70 oC) and cooling services (

  18. Thermal Efficiency of Power Module “Boiler with Solar Collectors as Additional Heat Source” For Combined Heat Supply System

    Directory of Open Access Journals (Sweden)

    Denysova A.E.

    2015-04-01

    Full Text Available The purpose of work is to increase the efficiency of the combined heat supply system with solar collectors as additional thermal generators. In order to optimize the parameters of combined heat supply system the mathematical modeling of thermal processes in multi module solar collectors as additional thermal generators for preheating of the water for boiler have been done. The method of calculation of multi-module solar collectors working with forced circulation for various configurations of hydraulic connection of solar collector modules as the new result of our work have been proposed. The results of numerical simulation of thermal efficiency of solar heat source for boiler of combined heat supply system with the account of design features of the circuit; regime parameters of thermal generators that allow establishing rational conditions of its functioning have been worked out. The conditions of functioning that provide required temperature of heat carrier incoming to boiler and value of flow rate at which the slippage of heat carrier is not possible for different hydraulic circuits of solar modules have been established.

  19. Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

    2013-01-01

    Integrating second generation bioethanol production in combined heat and power units is expected to increase system energy efficiencies while producing sustainable fuel for the transportation sector at a competitive price. By applying exergy analysis, this study assessed the efficiency of an inte......Integrating second generation bioethanol production in combined heat and power units is expected to increase system energy efficiencies while producing sustainable fuel for the transportation sector at a competitive price. By applying exergy analysis, this study assessed the efficiency...... of an integrated system in which steam extracted from an existing combined heat and power unit is used for covering the heating demand of a lignocellulosic ethanol production facility. The integration solution was designed and optimized using already existing steam extraction points in the combined heat and power...

  20. Combined Heat and Power Dispatch Considering Heat Storage of Both Buildings and Pipelines in District Heating System for Wind Power Integration

    Directory of Open Access Journals (Sweden)

    Ping Li

    2017-06-01

    Full Text Available The strong coupling between electric power and heat supply highly restricts the electric power generation range of combined heat and power (CHP units during heating seasons. This makes the system operational flexibility very low, which leads to heavy wind power curtailment, especially in the region with a high percentage of CHP units and abundant wind power energy such as northeastern China. The heat storage capacity of pipelines and buildings of the district heating system (DHS, which already exist in the urban infrastructures, can be exploited to realize the power and heat decoupling without any additional investment. We formulate a combined heat and power dispatch model considering both the pipelines’ dynamic thermal performance (PDTP and the buildings’ thermal inertia (BTI, abbreviated as the CPB-CHPD model, emphasizing the coordinating operation between the electric power and district heating systems to break the strong coupling without impacting end users’ heat supply quality. Simulation results demonstrate that the proposed CPB-CHPD model has much better synergic benefits than the model considering only PDTP or BTI on wind power integration and total operation cost savings.

  1. The combined heating and power station of Moabit. Circulating fluidized-bed combustion for better air in Berlin; Das Heizkraftwerk Moabit. Zirkulierende Wirbelschichtfeuerung fuer bessere Luft in Berlin

    Energy Technology Data Exchange (ETDEWEB)

    Bade, H.

    1993-08-01

    One main focus of the comprehensive environmental protection programme of the BEWAG (Berliner Kraft- und Licht Aktiengesellschaft) in order to reduce the emissions of the power stations was the modernisation of the combined heating and power station of Moabit. One heating block that had been erected in the middle of the fifties was replaced by a modern plant with the new technique of circulating fluidized bed combustion. The tradition of using the oldest power station of Berlin as a testing field for new directional technologies was carried on. Hence a new power station was erected that did not achieve the reduction of emissions by an additionally connected flue gas dust collector plant but by an environmentally harmless fuel engineering. Since the plant works according to the method of a combined heat and power generation the fuel utilisation is considerably higher than in the case of a pure current generation. The 100-MW heating and power station block with the circulating fluidized bed combustion is the largest plant of this kind in Germany at the present. (orig./KO). [Deutsch] Ein Schwerpunkt des umfassenden Umweltschutzprogrammes der BEWAG zur Senkung der Emissionen der Kraftwerke war die Modernisierung des Heizkraftwerkes Moabit. Als Ersatz fuer einen aus der Mitte der fuenfziger Jahre stammenden Block wurde hier mit der neuen Technik der zirkulierenden Wirbelschichtfeuerung (ZWS) eine moderne Anlage errichtet. Der Tradition des aeltesten Kraftwerkes Berlins als Versuchsfeld fuer neue richtungsweisende Techniken folgend entstand ein Kraftwerk, in dem die Emissionsreduzierung nicht durch nachgeschaltete Rauchgasreinigungsanlagen, sondern durch eine besonders umweltschonende Feuerungstechnik erreicht wurde. Da die Anlage nach dem Prinzip der Kraft-Waerme-Kopplung arbeitet, ist auch die Brennstoffausnutzung bedeutend hoeher als bei reiner Stromerzeugung. Der 100-MW-Heizkraftwerksblock mit ZWS-Feuerung ist die gegenwaertig groesste Anlage dieser Art in

  2. Robust Management of Combined Heat and Power Systems via Linear Decision Rules

    DEFF Research Database (Denmark)

    Zugno, Marco; Morales González, Juan Miguel; Madsen, Henrik

    2014-01-01

    The heat and power outputs of Combined Heat and Power (CHP) units are jointly constrained. Hence, the optimal management of systems including CHP units is a multicommodity optimization problem. Problems of this type are stochastic, owing to the uncertainty inherent both in the demand for heat...... and in the electricity prices that owners of CHP units receive for the power they sell in the market. In this work, we model the management problem for a coupled heat-and-power system comprising CHP plants, units solely producing heat as well as heat storages. We propose a robust optimization model including unit...... commitment, day-ahead power and heat dispatch as well as real-time re-dispatch (recourse) variables. This model yields a solution that is feasible under any realization of the heat demand within a given uncertainty set. Optimal recourse functions for the real-time operation of the units are approximated via...

  3. The Heat Transfer Coefficient of Recycled Concrete Bricks Combination with EPS Insulation Board Wall

    Directory of Open Access Journals (Sweden)

    Jianhua Li

    2015-01-01

    Full Text Available Four tectonic forms samples were conducted to test their heat transfer coefficients. By analyzing and comparing the test values and theoretical values of the heat transfer coefficient, a corrected-value calculation method for determining the heat transfer coefficient was proposed; the proposed method was proved to be reasonably correct. The results indicated that the recycled concrete brick wall heat transfer coefficient is higher than that of the clay brick wall, the heat transfer coefficient of recycled concrete brick wall could be effectively reduced when combined with the EPS insulation board, and the sandwich insulation type was better than that of external thermal insulation type.

  4. Heat of fusion storage systems for combined solar systems in low energy buildings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Furbo, Simon

    2004-01-01

    Solar heating systems for combined domestic hot water and space heating has a large potential especially in low energy houses where it is possible to take full advantage of low temperature heating systems. If a building integrated heating system is used – e.g. floor heating - the supply temperatu...... the storage is in its super cooled phase without activation of the phase change. This paper presents an initial simulation model of a PCM storage for implementation in TRNSYS 15 [1] as well as the first test results achieved with the model....

  5. Optimization of idealized ORC in domestic combined heat and power generation

    Science.gov (United States)

    Rybiński, Witold; Mikielewicz, Jarosław

    2013-09-01

    Organic Rankine cycle (ORC) is used, amongst the others, in geothermal facilities, in waste heat recovery or in domestic combined heat and power (CHP) generation. The paper presents optimization of an idealized ORC equivalent of the Carnot cycle with non-zero temperature difference in heat exchangers and with energy dissipation caused by the viscous fluid flow. In this analysis the amount of heat outgoing from the ORC is given. Such a case corresponds to the application of an ORC in domestic CHP. This assumption is different from the most of ORC models where the incoming amount of heat is given.

  6. Macroscopic Fault Structure of the 1911 Mw8.1 Chon Kemin Earthquake (Tien Shan, Kyrgyzstan) from Combined Seismic Imaging, Palaeo-Seismological Investigations and Historial Seismicity

    Science.gov (United States)

    Haberland, C. A.; Sonnemann, T.; Landgraf, A.; Ryberg, T.; Kulikova, G.; Krueger, F.; Dzhumabaeva, A.; Abdrakhmatov, K.; Abdybachaev, U.; Orunbaev, S.; Rosenwinkel, S.; Sharshebaev, A.

    2014-12-01

    Earthquakes in low-strain regions and their driving forces are still sparsely studied and understood, and constitute serious first-order research questions. Data acquisition concerning paleo-earthquakes, related hazards, and tectonic activity beyond historical records plays an important role. Such information can be obtained with tools from tectonic geomorphology, geophysics, historic seismicity, and paleo-seismology that should span a variety of time and length scales. The Chon-Kemin Valley in the northern Tien Shan (Kyrgyzstan) is a small, intermontane basin of unknown origin framed by a network of active faults. In the year 1911, the Chon-Kemin earthquake (Mw=8.1) activated fault structures of about 200 km length which also ruptured the surface along the Chon-Kemin Valley and caused numerous landslides and rock avalanches of up to several tens of millions of cubic meters in volume. The Chon-Kemin earthquake was one of a series of strong seismic events that affected the northern Tien Shan between 1885 and 1938. A seismic survey across the Chon-Kemin Valley was conducted to investigate the subsurface velocity structure of the valley and its surrounding faults. Tomographic inversion techniques were applied to first-arrival traveltimes of refracted P waves, and the seismic data were screened for reflection signatures. Additionally, the region was analyzed through paleo-seismological trenching. Tomographic and reflection images identified a shallow basin structure bounded by a set of thrust faults in the south only which - in part - correlate with the surface trace of the rupture. The deformation seems to be distributed in time and space across several sub-parallel fault strands. Synthesis of historical (analog) recordings of this earthquake provide new insights into the source mechanisms and processes.

  7. Combined heat and moisture transfer in buildings systems

    OpenAIRE

    Damle, Rashmin; Lehmkuhl Barba, Oriol; Rigola Serrano, Joaquim; Oliva Llena, Asensio

    2012-01-01

    Temperature and humidity are the two main parameters indicating the comfort level of the building occupants. Although the effect of temperature is taken into account in thermal simulation of buildings, the moisture transfer through the rooms and porous building walls is sometimes neglected. The level of humidity can give different sensations of thermal comfort. It is necessary to take into account both heat and moisture transport in and around buildings to predict the hygrothermal behavior of...

  8. Demonstration of 5MW PAFC power plant

    Energy Technology Data Exchange (ETDEWEB)

    Usami, Yutaka [Phosphoric Acid Fuel Cell Technology Research Association, Osaka (Japan); Takae, Toshio [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1996-12-31

    Phosphoric Acid Fuel Cell Technology Research Association, established in May 1991 by Japanese 10 electric power and 4 gas companies, started a new project in 1991 FY, with the object of PAFC realization and aiming the development of 5MW- class PAFC. power plant for urban energy center and 1 MW- class power plant for onsite use. This project is carried out as 6 years plan jointly with New Energy and Industrial Technology Development Organization. The targets of the project are to evaluate and resolve the development task, such as a high reliability, compactness and cost reduction throughout the engineering, manufacturing and field testing of PAFC power plants. PAC tests and power generating test operations of 5MW plant were completed in 1994. Conducting the 2 years continuous operations and studies since 1995, the plant operational performance, system control characteristics, waste heat recovery and environmental advantage will be demonstrated.

  9. Optimization of micro combined heat and power gas turbine by genetic algorithm

    OpenAIRE

    Yazdi Behnam Ahrar; Yazdi Behdad Ahrar; Ehyaei Mehdi Ali; Ahmadi Abolfazl

    2015-01-01

    In this paper, a comprehensive thermodynamic modeling and multi-objective optimization of a micro turbine cycle in combined heat and power generation, which provides 100KW of electric power. This CHP System is composed of air compressor, combustion chamber (CC), Air Preheater, Gas Turbine (GT) and a Heat Recovery Heat Exchanger. In this paper, at the first stage, the each part of the micro turbine cycle is modeled using thermodynamic laws. Next, with using ...

  10. Thermodynamic Analysis of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

    Directory of Open Access Journals (Sweden)

    Mirko Grljušić

    2014-11-01

    Full Text Available The goal of this research is to study a cogeneration plant for combined heat & power (CHP production that utilises the low-temperature waste energy in the power plant of a Suezmax-size oil tanker for all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency and a CHP Plant with R245fa fluid using a supercritical organic Rankine cycle (ORC is selected. All the ship heat requirements can be covered by energy of organic fluid after expansion in the turbine, except feeder-booster heating. Hence, an additional quantity of working fluid may be heated using an after Heat Recovery Steam Generator (HRSG directed to the feeder-booster module. An analysis of the obtained results shows that the steam turbine plant does not yield significant fuel savings. However, a CHP plant with R245fa fluid using supercritical ORC meets all of the demands for electrical energy and heat while burning only a small amount of additional fuel in HRSG at the main engine off-design operation.

  11. Modeling and simulation of combined gas turbine engine and heat pipe system for waste heat recovery and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Lamfon, N.J. [Saudi Aramco Jeddah Refinery, Jeddah (Saudi Arabia); Najjar, Y.S.H.; Akyurt, M. [King Abdulaziz Univ., Mechanical Engineering Dept., Jeddah (Saudi Arabia)

    1998-12-01

    The results of a modeling and simulation study are presented for a combined system consisting of a gas turbine engine, a heat pipe recovery system and an inlet-air cooling system. The presentation covers performance data related to the gas turbine engine with precooled air intake as coupled to the water-in-copper heat pipe recovery system. This is done by matching the two mathematical models. The net power output is improved by 11% when the gas turbine engine is supplied with cold air produced by the heat-pipe recovery and utilization system. It is further concluded from the results produced by the combined mathematical model that the thermal efficiency of the gas turbine engine rises to 6% at 75% part load. It is to be anticipated that this rising trend in increases of thermal efficiency of the gas turbine engine would continue for operations at other (lower) part load conditions. (author)

  12. A combined gray neural network model of seasonal heating load forecast

    Institute of Scientific and Technical Information of China (English)

    QIAOXiaozhuang; YANGChangzhi

    2003-01-01

    Seasonal heating load time sequence has the double trends of increasing and fluctuating, so it''s difficult to select a model to forecast it. In this paper, a combined model of gray model and artificial neural network model was presented to forecast seasonal heating load. A concrete model was established and was verified through actual examples.

  13. Fuel and Carbon Dioxide Emissions Savings Calculation Methodology for Combined Heat and Power Systems

    Science.gov (United States)

    This paper provides the EPA Combined Heat and Power Partnership's recommended methodology for calculating fuel and carbon dioxide emissions savings from CHP compared to SHP, which serves as the basis for the EPA's CHP emissions calculator.

  14. The Role of Distributed Generation and Combined Heat and Power (CHP) Systems in Data Centers

    Science.gov (United States)

    This report reviews how distributed generation (DG) resources such as fuel cells, reciprocating engines, and gas turbines can offer powerful energy efficiency savings in data centers, particularly when configured in combined heat and power (CHP) mode.

  15. Waste-heat boiler application for the Vresova combined cycle plant

    Energy Technology Data Exchange (ETDEWEB)

    Vicek, Z. [Energoprojekt Praha, Prague (Czechoslovakia)

    1995-12-01

    This report describes a project proposal and implementation of two combined-cycle units of the Vresova Fuel Complex (PKV) with 2 x 200 MWe and heat supply. Participation of ENERGOPROJECT Praha a.s., in this project.

  16. Numerical Simulation of Combustion Characteristics of a 300 MW Blast Furnace Gas/Pulverized Coal Combined Combustion Boiler%300MW煤粉/高炉煤气混燃锅炉燃烧特性数值模拟

    Institute of Scientific and Technical Information of China (English)

    王春波; 魏建国; 盛金贵; 李艳奇

    2012-01-01

    Blast furnace gas(BFG) produced from steel mill is a low heat value fuel,which combined with pulverized coal to combust in boiler is one of effective ways.However,the combustion characteristics would be changed greatly when compared with only pulverized coal combustion.For example,superheaters and reheaters are easy to excess rated temperatures and carbon content in fly ash will become higher,etc.All these problems lead to its limited application today.Take a 300MW BFG/pulverized coal boiler for example,the combustion characteristics were simulated by means of two mixture fractions way.The pure coal condition and three BFG ratio: 10%,20% and 30% conditions were investigated.It shows the temperature level in boiler is lowered obviously when BFG was mixed into boiler.For example,the maximal temperature is lowered about 81K when BFG ratio is 10% for a boiler section.Also,the temperature becomes lower with the BFG ratio.When BFG was mixed into boiler the flue gases volume would be increased.So,the actual stay time for pulverized coal in boiler will be shortened and it is more difficulty for coal to combust completely.Aslo,it is helpfully for control NO emission when BFG was mixed into boiler.%钢厂高炉煤气是一种低热值燃料,它和煤粉在炉内掺烧是其一种有效的利用途径。但煤粉掺烧高炉煤气后燃烧特性与纯煤粉燃烧有很大不同,掺烧过程中易发生过/再热器超温、飞灰含碳量过高等问题,导致其在大型锅炉上的应用很少。针对某钢厂300MW四角切圆煤粉/高炉煤气混燃锅炉,使用二混合分数法对其燃烧特性进行数值模拟。对比研究了纯燃煤工况和高炉煤气掺烧量分别为10%、20%、30%的工况,发现掺烧高炉煤气时炉内温度水平有明显下降(如,掺烧10%高炉煤气时截面最高温度降低81K),且随着掺烧量的增加而加剧,但下降的趋势变缓。掺烧高炉煤气后产生烟气量增多,炉膛出口烟速有明显增加,

  17. Thermodynamic analysis of heat recovery steam generator in combined cycle power plant

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Naradasu

    2007-01-01

    Full Text Available Combined cycle power plants play an important role in the present energy sector. The main challenge in designing a combined cycle power plant is proper utilization of gas turbine exhaust heat in the steam cycle in order to achieve optimum steam turbine output. Most of the combined cycle developers focused on the gas turbine output and neglected the role of the heat recovery steam generator which strongly affects the overall performance of the combined cycle power plant. The present paper is aimed at optimal utilization of the flue gas recovery heat with different heat recovery steam generator configurations of single pressure and dual pressure. The combined cycle efficiency with different heat recovery steam generator configurations have been analyzed parametrically by using first law and second law of thermodynamics. It is observed that in the dual cycle high pressure steam turbine pressure must be high and low pressure steam turbine pressure must be low for better heat recovery from heat recovery steam generator.

  18. Combined Heat & Power Using the Infinia Concentrated Solar CHP PowerDish System

    Science.gov (United States)

    2013-08-01

    FINAL REPORT Combined Heat & Power Using the Infinia Concentrated Solar CHP PowerDish System ESTCP Project EW-201145 AUGUST 2013...Combined Heat & Power Using the Infinia Concentrated Solar CHP PowerDish System 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...demonstrated the capabilities of the Infinia PowerDish? CHP technology to generate clean solar thermal and electric energy compatible with domestic and

  19. Calculation of Efficiencies of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

    Directory of Open Access Journals (Sweden)

    Mirko Grljušić

    2015-05-01

    Full Text Available The aim of this research was to investigate the possibility of a combined heat & power (CHP plant, using the waste heat from a Suezmax-size oil tanker’s main engine, to meet all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency, combined with a supercritical Organic Rankine cycle (ORC system, was selected to supply the auxiliary power, using R245fa or R123 as the working fluid. The system analysis showed that such a plant can meet all heat and electrical power requirements at full load, with the need to burn only a small amount of supplementary fuel in a heat recovery steam generator (HRSG when the main engine operates at part load. Therefore, it is possible to increase the overall thermal efficiency of the ship’s power plant by more than 5% when the main engine operates at 65% or more of its specified maximum continuous rating (SMCR.

  20. Phosphoproteomic analysis of the response of maize leaves to drought, heat and their combination stress

    Directory of Open Access Journals (Sweden)

    Xiuli eHu

    2015-05-01

    Full Text Available Drought and heat stress, especially their combination, greatly affect crop production. Many studies have described transcriptome, proteome and phosphoproteome changes in response of plants to drought or heat stress. However, the study about the phosphoproteomic changes in response of crops to the combination stress is scare. To understand the mechanism of maize responses to the drought and heat combination stress, phosphoproteomic analysis was performed on maize leaves by using multiplex iTRAQ-based quantitative proteomic and LC-MS/MS methods. Five-leaf-stage maize was subjected to drought, heat or their combination, and the leaves were collected. Globally, heat, drought and the combined stress significantly changed the phosphorylation levels of 172, 149 and 144 phosphopeptides, respectively. These phosphopeptides corresponded to 282 proteins. Among them, 23 only responded to the combined stress and could not be predicted from their responses to single stressors; 30 and 75 only responded to drought and heat, respectively. Notably, 19 proteins were phosphorylated on different sites in response to the single and combination stresses. Of the seven significantly enriched phosphorylation motifs identified, two were common for all stresses, two were common for heat and the combined stress, and one was specific to the combined stress. The signaling pathways in which the phosphoproteins were involved clearly differed among the three stresses. Functional characterization of the phosphoproteins and the pathways identified here could lead to new targets for the enhancement of crop stress tolerance, which will be particularly important in the face of climate change and the increasing prevalence of abiotic stressors.

  1. 200 MW供热机组双机单塔运行的节能分析%Energy Saving Analysis of 200 MW Heating Unit Double Machine Double Tower Operation

    Institute of Scientific and Technical Information of China (English)

    李建新; 李文林

    2016-01-01

    Ningxia Electric Power Investment Group in Xixia thermal power plant 200MW unit in winter heating condition, change the mode of operation of the cooling tower by the twin towers switched to single tower operation, reduce the auxiliary power consumption rate, reduce the difference of the condenser end, reducing the cooling tower of water supply, to avoid the cooling Tower of a large number of ice, water consumption decreased significantly, to achieve the purpose of energy saving unit.%宁夏电力投资集团西夏热电厂200MW供热机组在冬季采暖工况下,改变冷却塔的运行方式由双塔切换至单塔运行,降低了厂用电率,减小了凝汽器的端差,降低了冷却塔的补水量,避免了冷却塔的大量结冰,水耗明显降低,达到机组节能目的。

  2. Combined solar heat and power system with a latent heat storage - system simulations for an economic assessment

    Science.gov (United States)

    Zipf, Verena; Neuhäuser, Anton

    2016-05-01

    Decentralized solar combined heat and power (CHP) systems can be economically feasible, especially when they have a thermal storage. In such systems, heat provided by solar thermal collectors is used to generate electricity and useful heat for e.g. industrial processes. For the supply of energy in times without solar irradiation, a thermal storage can be integrated. In this work, the performance of a solar CHP system using an active latent heat storage with a screw heat exchanger is investigated. Annual yield calculations are conducted in order to calculate annual energy gains and, based on them; economic assumptions are used to calculated economic numbers in order to assess the system performance. The energy savings of a solar system, compared to a system with a fossil fuel supply, are calculated. Then the net present value and the dynamic payback are calculated with these savings, the initial investment costs and the operational costs. By interpretation and comparison of these economic numbers, an optimum system design in terms of solar field size and storage size was determined. It has been shown that the utilization of such systems can be economical in remote areas without gas and grid connection. Optimal storage design parameters in terms of the temperature differences in the heat exchanger and the storage capacity have been determined which can further increase the net present value of such system.

  3. PCFB Repowering Project 80 MW plant description

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    This report documents the design of a 80 MW Pressurized Circulating Fluidized Bed (PCFB) boiler for the repowering of Unit 1 at the Des Moines Energy Center. Objective is to demonstrate that PCFB combined-cycle technology is cost effective and environmentally superior compared to traditional pulverized coal burning facilities.

  4. Combined Influence of Strain and Heat Loss on Turbulent Premixed Flame Stabilization

    KAUST Repository

    Tay-Wo-Chong, Luis

    2015-11-16

    The present paper argues that the prediction of turbulent premixed flames under non-adiabatic conditions can be improved by considering the combined effects of strain and heat loss on reaction rates. The effect of strain in the presence of heat loss on the consumption speed of laminar premixed flames was quantified by calculations of asymmetric counterflow configurations (“fresh-to-burnt”) with detailed chemistry. Heat losses were introduced by setting the temperature of the incoming stream of products on the “burnt” side to values below those corresponding to adiabatic conditions. The consumption speed decreased in a roughly exponential manner with increasing strain rate, and this tendency became more pronounced in the presence of heat losses. An empirical relation in terms of Markstein number, Karlovitz Number and a non-dimensional heat loss parameter was proposed for the combined influence of strain and heat losses on the consumption speed. Combining this empirical relation with a presumed probability density function for strain in turbulent flows, an attenuation factor that accounts for the effect of strain and heat loss on the reaction rate in turbulent flows was deduced and implemented into a turbulent combustion model. URANS simulations of a premixed swirl burner were carried out and validated against flow field and OH chemiluminescence measurements. Introducing the effects of strain and heat loss into the combustion model, the flame topology observed experimentally was correctly reproduced, with good agreement between experiment and simulation for flow field and flame length.

  5. Trials of combined radiation and hyperthermia with various heating modalities in cancer therapy.

    Science.gov (United States)

    Egawa, S; Ishioka, K; Kawada, Y

    1984-01-01

    A microwave heating apparatus with a frequency of 2,450 MHz and an inductive radio-frequency heating apparatus were developed for hyperthermia for cancer therapy, and clinical trials of combined radiation and hyperthermia were conducted. During the same period, a capacitive type radiofrequency unit was used. The tumors included superficial tumors, cancer of the uterine cervix, recurrent tumors at the stump of the cervix, and some deep-seated tumors. Cases showing complete response were as follows: 5 out of 13 cases treated with 2,450 MHz heating for superficial tumors, 8 out of 17 cases treated with 2,450 MHz intracavitary heating, and 2 out of 15 cases treated with radiofrequency heating. A feasibility study of various heating modalities was performed.

  6. Wood chip drying in connection with combined heat and power or solar energy in Finland

    Science.gov (United States)

    Rinne, Samuli; Holmberg, Henrik; Myllymaa, Tiina; Kontu, Kaisa; Syri, Sanna

    2014-12-01

    20% of the Finnish district heating (DH) power plant fuels are wood-based and the share is increasing. The wood fuel demand probably exceeds the potential supply in the future. The wood fuel drying with waste heat is one profitable opportunity to gain more wood fuel. If the drying energy can be produced with lower primary energy use than combusting the fuel directly, the drying potentially improves the system efficiency. In this study, the drying feasibility in the connection of a combined heat and power (CHP) system, possibly with solar collectors, is calculated. The wood fuel heating can be increased profitably by 6%, using the heat from CHP for drying only when the marginal cost of the heat is low enough, i.e. the electricity price is high enough and there is free capacity after the DH demand. Although the drying is profitable, a larger heat storage can also increase the annual result similarly. The best investment choice depends on the plant properties. Here the optimal system enables 20% DH production cost savings. Solar heat may be profitable, when the solar heat has a 2-3% share of the annual heat demand. However, the dryer or larger storage tank are more profitable investments.

  7. Wood chip drying in connection with combined heat and power or solar energy in Finland

    Directory of Open Access Journals (Sweden)

    Rinne Samuli

    2014-01-01

    Full Text Available 20% of the Finnish district heating (DH power plant fuels are wood-based and the share is increasing. The wood fuel demand probably exceeds the potential supply in the future. The wood fuel drying with waste heat is one profitable opportunity to gain more wood fuel. If the drying energy can be produced with lower primary energy use than combusting the fuel directly, the drying potentially improves the system efficiency. In this study, the drying feasibility in the connection of a combined heat and power (CHP system, possibly with solar collectors, is calculated. The wood fuel heating can be increased profitably by 6%, using the heat from CHP for drying only when the marginal cost of the heat is low enough, i.e. the electricity price is high enough and there is free capacity after the DH demand. Although the drying is profitable, a larger heat storage can also increase the annual result similarly. The best investment choice depends on the plant properties. Here the optimal system enables 20% DH production cost savings. Solar heat may be profitable, when the solar heat has a 2–3% share of the annual heat demand. However, the dryer or larger storage tank are more profitable investments.

  8. Opportunities for Combined Heat and Power in Data Centers

    Energy Technology Data Exchange (ETDEWEB)

    Darrow, Ken [ICF International; Hedman, Bruce [ICF International

    2009-03-01

    types of facilities involved, and the geographic distribution. (2) Data Center Energy Use Trends--a discussion of energy use and expected energy growth and the typical energy consumption and uses in data centers. (3) CHP Applicability--Potential configurations, CHP case studies, applicable equipment, heat recovery opportunities (cooling), cost and performance benchmarks, and power reliability benefits (4) CHP Drivers and Hurdles--evaluation of user benefits, social benefits, market structural issues and attitudes toward CHP, and regulatory hurdles. (5) CHP Paths to Market--Discussion of technical needs, education, strategic partnerships needed to promote CHP in the IT community.

  9. Exergy, Economic and Environmental Analysis for Simple and Combined Heat and Power IC Engines

    Directory of Open Access Journals (Sweden)

    Mehdi Aliehyaei

    2015-04-01

    Full Text Available This study reports the results of exergy, economic and environmental analyses of simple and combined heat and power internal combustion engines. Values of entropy production, second law efficiency are calculated, and an objective function, including initial, operation, maintenance and fuel costs, as well as the external costs of environmental pollutants, such as CO2, CO and NOx, are presented for the flue gas of the internal combustion engine. The results show that entropy generation in the combined heat and power mode is 30% lower than that in the simple internal combustion engine. Also, by excessively increasing the air ratio, the system entropy generation decreases in both cases of simple and combined heat and power IC engines. The greatest portion of entropy generation is related to the combined heat and power internal combustion engine. The gas heat exchanger generates more entropy than the jacket heat exchanger. Lower values of electricity cost and external costs of air pollution are provided by higher values of molar air to fuel ratio. The environmental aspects depend on location of the system and time of engine operation.

  10. Combining Satellite Microwave Radiometer and Radar Observations to Estimate Atmospheric Latent Heating Profiles

    Science.gov (United States)

    Grecu, Mircea; Olson, William S.; Shie, Chung-Lin; L'Ecuyer, Tristan S.; Tao, Wei-Kuo

    2009-01-01

    In this study, satellite passive microwave sensor observations from the TRMM Microwave Imager (TMI) are utilized to make estimates of latent + eddy sensible heating rates (Q1-QR) in regions of precipitation. The TMI heating algorithm (TRAIN) is calibrated, or "trained" using relatively accurate estimates of heating based upon spaceborne Precipitation Radar (PR) observations collocated with the TMI observations over a one-month period. The heating estimation technique is based upon a previously described Bayesian methodology, but with improvements in supporting cloud-resolving model simulations, an adjustment of precipitation echo tops to compensate for model biases, and a separate scaling of convective and stratiform heating components that leads to an approximate balance between estimated vertically-integrated condensation and surface precipitation. Estimates of Q1-QR from TMI compare favorably with the PR training estimates and show only modest sensitivity to the cloud-resolving model simulations of heating used to construct the training data. Moreover, the net condensation in the corresponding annual mean satellite latent heating profile is within a few percent of the annual mean surface precipitation rate over the tropical and subtropical oceans where the algorithm is applied. Comparisons of Q1 produced by combining TMI Q1-QR with independently derived estimates of QR show reasonable agreement with rawinsonde-based analyses of Q1 from two field campaigns, although the satellite estimates exhibit heating profile structure with sharper and more intense heating peaks than the rawinsonde estimates. 2

  11. Optimization of Serial Combined System of Ground-Coupled Heat Pump and Solar Collector

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jun; CHEN Yan; LU Suzhen; CUI Junkui

    2009-01-01

    A mathematical optimization model was set up for a ground-solar combined system based on in-situ experimental results,in which the solar collector was combined serially with a ground-coupled heat pump(GCHP).The universal optimal equations were solved by the constrained variable metric method considering both the performance and economics.Then the model was applied to a specific case concerning an actual solar assisted GCHP system for space heating.The results indicated a system coefficient of performance(COP)of 3.9 for the optimal method under the seriaI heating mode,and 3.2 for the conventional one.In addition,the optimum solution also showed advantages in energy and cost saving.1eading to a 16.7%improvement in the heat pump performance at 17.2%less energy consumption and 11.8%lower annual cost,respectively.

  12. Subjective evaluation of different ventilation concepts combined with radiant heating and cooling

    DEFF Research Database (Denmark)

    Krajcik, Michal; Tomasi, Roberta; Simone, Angela

    2012-01-01

    with displacement ventilation. Vertical air temperature distribution was more uniform for floor heating than for warm air heating, but there was no significant difference in thermal perception between the two mixing ventilation systems. For the summer conditions the subjects voted warmer than predicted by the PMV...... supplying warm air space heating or by a combination of radiant floor heating and mixing ventilation system. Next two test setups simulated an office room with two occupants during summer, ventilated and cooled by a single displacement ventilation system or by a radiant floor cooling combined...... and about one third preferred more air movement. No significant difference in thermal perception between the two displacement ventilation systems was found....

  13. Exergy costing for energy saving in combined heating and cooling applications

    DEFF Research Database (Denmark)

    Nguyen, Chan; Veje, Christian T.; Willatzen, Morten

    2014-01-01

    The aim of this study is to provide a price model that motivates energy saving for a combined district heating and cooling system. A novel analysis using two thermoeconomic methods for apportioning the costs to heating and cooling provided simultaneously by an ammonia heat pump is demonstrated....... In the first method, referred to as energy costing, a conventional thermoeconomic analysis is used. Here the ammonia heat pump is subject to a thermodynamic analysis with mass and energy balance equations. In the second method referred to as exergy costing, an exergy based economic analysis is used, where....... The analysis shows that the two methods yield significantly different results. Rather surprisingly, it is demonstrated that the exergy costing method results in about three times higher unit cost for heating than for cooling as opposed to equal unit costs when using the energy method. Further the exergy-based...

  14. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    OpenAIRE

    Florian Heberle; Dieter Brüggemann

    2014-01-01

    We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC) in a combined heat and power generation (CHP) case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency...

  15. Combined heat and power economic dispatch by a fish school search algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Leonardo Trigueiro dos; Costa e Silva, Marsil de Athayde [Undergraduate in Mechatronics Engineering, Pontifical Catholic University of Parana, Curitiba, PR (Brazil); Coelho, Leandro dos Santos [Industrial and Systems Engineering Graduate Program, PPGEPS, Pontifical Catholic University of Parana, Curitiba, PR (Brazil)], e-mail: leandro.coelho@pucpr.br

    2010-07-01

    The conversion of primary fossil fuels, such as coal and gas, to electricity is a a relatively inefficient process. Even the most modern combined cycle plants can only achieve efficiencies of between 50-60%. A great portion of the energy wasted in this conversion process is released to the environment as waste heat. The principle of combined heat and power, also known as cogeneration, is to recover and make beneficial use of this heat, significantly raising the overall efficiency of the conversion process. However, the optimal utilization of multiple combined heat and power systems is a complicated problem which needs powerful methods to solve. This paper presents a fish school search (FSS) algorithm to solve the combined heat and power economic dispatch problem. FSS is a novel approach recently proposed to perform search in complex optimization problems. Some simulations presented in the literature indicated that FSS can outperform many bio-inspired algorithms, mainly in multimodal functions. The search process in FSS is carried out by a population of limited-memory individuals - the fishes. Each fish represents a possible solution to the problem. Similarly to particle swarm optimization or genetic algorithm, search guidance in FSS is driven by the success of some individual members of the population. A four-unit system proposed recently which is a benchmark case in the power systems field has been validated as a case study in this paper. (author)

  16. Optimization of operation for combined heat and power plants - CHP plants - with heat accumulators using a MILP formulation

    Energy Technology Data Exchange (ETDEWEB)

    Grue, Jeppe; Bach, Inger [Aalborg Univ. (Denmark). Inst. of Energy Technology]. E-mails: jeg@iet.auc.dk; ib@iet.auc.dk

    2000-07-01

    The power generation system in Denmark is extensively based on small combined heat and power plants (CHP plants), producing both electricity and district heating. This project deals with smaller plants spread throughout the country. Often a heat accumulator is used to enable electricity production, even when the heat demand is low. This system forms a very complex problem, both for sizing, designing and operation of CHP plants. The objective of the work is the development of a tool for optimisation of the operation of CHP plants, and to even considering the design of the plant. The problem is formulated as a MILP-problem. An actual case is being tested, involving CHP producing units to cover the demand. The results from this project show that it is of major importance to consider the operation of the plant in detail already in the design phase. It is of major importance to consider the optimisation of the plant operation, even at the design stage, as it may cause the contribution margin to rise significantly, if the plant is designed on the basis of a de-tailed knowledge of the expected operation. (author)

  17. Methods for planning and operating decentralized combined heat and power plants

    Energy Technology Data Exchange (ETDEWEB)

    Palsson, H.

    2000-02-01

    In recent years, the number of decentralized combined heat and power (DCHP) plants, which are typically located in small communities, has grown rapidly. These relatively small plants are based on Danish energy resources, mainly natural gas, and constitute an increasing part of the total energy production in Denmark. The topic of this thesis is the analysis of DCHP plants, with the purpose to optimize the operation of such plants. This involves the modelling of district heating systems, which are frequently connected to DCHP plants, as well as the use of heat storage for balancing between heat and power production. Furthermore, the accumulated effect from increasing number of DCHP plants on the total power production is considered. Methods for calculating dynamic temperature response in district heating (DH) pipes have been reviewed and analyzed numerically. Furthermore, it has been shown that a tree-structured DH network consisting of about one thousand pipes can be reduced to a simple chain structure of ten equivalent pipes without loosing much accuracy when temperature dynamics are calculated. A computationally efficient optimization method based on stochastic dynamic programming has been designed to find an optimum start-stop strategy for a DCHP plant with a heat storage. The method focuses on how to utilize heat storage in connection with CHP production. A model for the total power production in Eastern Denmark has been applied to the accumulated DCHP production. Probability production simulations have been extended from the traditional power-only analysis to include one or several heat supply areas. (au)

  18. Combined Heat Transfer in High-Porosity High-Temperature Fibrous Insulations: Theory and Experimental Validation

    Science.gov (United States)

    Daryabeigi, Kamran; Cunnington, George R.; Miller, Steve D.; Knutson, Jeffry R.

    2010-01-01

    Combined radiation and conduction heat transfer through various high-temperature, high-porosity, unbonded (loose) fibrous insulations was modeled based on first principles. The diffusion approximation was used for modeling the radiation component of heat transfer in the optically thick insulations. The relevant parameters needed for the heat transfer model were derived from experimental data. Semi-empirical formulations were used to model the solid conduction contribution of heat transfer in fibrous insulations with the relevant parameters inferred from thermal conductivity measurements at cryogenic temperatures in a vacuum. The specific extinction coefficient for radiation heat transfer was obtained from high-temperature steady-state thermal measurements with large temperature gradients maintained across the sample thickness in a vacuum. Standard gas conduction modeling was used in the heat transfer formulation. This heat transfer modeling methodology was applied to silica, two types of alumina, and a zirconia-based fibrous insulation, and to a variation of opacified fibrous insulation (OFI). OFI is a class of insulations manufactured by embedding efficient ceramic opacifiers in various unbonded fibrous insulations to significantly attenuate the radiation component of heat transfer. The heat transfer modeling methodology was validated by comparison with more rigorous analytical solutions and with standard thermal conductivity measurements. The validated heat transfer model is applicable to various densities of these high-porosity insulations as long as the fiber properties are the same (index of refraction, size distribution, orientation, and length). Furthermore, the heat transfer data for these insulations can be obtained at any static pressure in any working gas environment without the need to perform tests in various gases at various pressures.

  19. Combined impact of transient heat loads and steady-state plasma exposure on tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Alexander, E-mail: A.Huber@fz-juelich.de [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Wirtz, Marius; Sergienko, Gennady; Steudel, Isabel [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Arakcheev, Aleksey; Burdakov, Aleksander [Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); Esser, Hans Guenter; Freisinger, Michaele; Kreter, Arkadi; Linke, Jochen; Linsmeier, Christian; Mertens, Philippe; Möller, Sören; Philipps, Volker; Pintsuk, Gerald; Reinhart, Michael; Schweer, Bernd [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Shoshin, Andrey [Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); Terra, Alexis; Unterberg, Bernhard [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany)

    2015-10-15

    Highlights: • W-samples under combined loading conditions show a lower damage threshold. • The pre-loaded W-samples show a lower damage threshold due to the D- embrittlement. • Pronounced increase of the D retention has been observed during the combined loads. • Enhanced blister formation has been observed under combined loading conditions. - Abstract: Cracking thresholds and crack patterns in tungsten targets have been studied in recent experiments after repetitive ITER-like ELM heat pulses in combination with plasma exposure in PSI-2 (Γ{sub target} = 2.5–4.0 × 10{sup 21} m{sup −2} s{sup −1}, ion energy on surface E{sub ion} = 60 eV, T{sub e} ≈ 10 eV). The heat pulses were simulated by laser irradiation. A Nd:YAG laser with energy per pulse of up to 32 J and a duration of 1 ms at the fundamental wavelength (λ = 1064 nm, repetition rate 0.5 Hz) was used to irradiate ITER-grade W samples with repetitive heat loads. In contrast to pure thermal exposure with a laser beam where the damage threshold under pure heat loads for ITER-grade W lies between 0.38 and 0.76 GW/m{sup 2}, the experiments with pre-loaded W-samples as well as under combined loading conditions show a lower damage threshold of 0.3 GW/m{sup 2}. This is probably due to deuterium embrittlement and/or a higher defect concentration in a region close to the surface due to supersaturation with deuterium. A pronounced increase in the D retention (more than a factor of five) has been observed during the combined transient heat loads and plasma exposure. Enhanced blister formation has been observed under these combined loading conditions.

  20. Technologies for small scale wood-fueled combined heat and power systems

    Energy Technology Data Exchange (ETDEWEB)

    Houmann Jakobsen, H.; Houmoeller, S.; Thaaning Pedersen, L.

    1998-01-01

    The aim of this study is to describe and compare different technologies for small cogeneration systems (up to 2-3 MW{sub e}), based on wood as fuel. For decentralized cogeneration, i.e. for recovering energy from saw mill wood wastes or heat supply for small villages, it is vital to know the advantages and disadvantages of the different technologies. Also, for the decision-makers it is of importance to know the price levels of the different technologies. A typical obstacle for small wood cogeneration systems is the installation costs. The specific price (per kW) is usually higher than for larger plants or plants using fossil fuels. For a saw mill choosing between cogeneration and simple heat production, however, the larger installation costs are counter weighed by the sale of electricity, while the fuel consumption is the same. Whether it is profitable or not to invest in cogeneration is often hard to decide. For many years small wood cogeneration systems have been too expensive, leading to the construction of only heat producing systems due to too high price levels of small steam turbines. In recent years a great deal of effort has been put into research and developing of new technologies to replace this traditional steam turbine. Among these are: Steam engines; Stirling engines; Indirectly fired gas turbines; Pressurized down draft combustion. Along with the small scale traditional steam turbines, these technologies will be evaluated in this study. When some or all these technologies are fully developed and commercial, a strong means of reducing the strain on the environment and the greenhouse effect will be available, as the total efficiency is high (up to 90%) and wood is an energy source in balance with nature. (au) EFP-95. 19 refs.

  1. Carbon emission impact on the operation of virtual power plant with combined heat and power system

    Institute of Scientific and Technical Information of China (English)

    Yu-hang XIA; Jun-yong LIU; Zheng-wen HUANG; Xu ZHANG

    2016-01-01

    A virtual power plant (VPP) can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of VPPs and ever-growing heat demand of consumers, managing the effect of fluctuations in the amount of available renewable resources on the operation of VPPs and maintaining an economical supply of electric power and heat energy to users have been important issues. This paper proposes the allocation of an electric boiler to realize wind power directly converted for supplying heat, which can not only overcome the limitation of heat output from a combined heat and power (CHP) unit, but also reduce carbon emissions from a VPP. After the electric boiler is considered in the VPP operation model of the combined heat and power system, a multi-objective model is built, which includes the costs of carbon emissions, total operation of the VPP and the electricity traded between the VPP and the main grid. The model is solved by the CPLEX package using the fuzzy membership function in Matlab, and a case study is pre-sented. The power output of each unit in the case study is analyzed under four scenarios. The results show that after carbon emission is taken into account, the output of low carbon units is significantly increased, and the allocation of an electric boiler can facilitate the maximum absorption of renewable energy, which also reduces carbon emissions from the VPP.

  2. The Development of Coke Carried—Heat Gasification Coal—Fired Combined Cycle

    Institute of Scientific and Technical Information of China (English)

    LiZhao; XiangdongXu

    1999-01-01

    Carried-Heat Partial Gasification Combined cycle is a novel combined cycle which was proposed by Thermal Engineering Department of Tsinghua University in 1992,The idea of the system comes from the situation that the efficiency of the power plants in china is much lower than that of the advanced countries,but the coal consumption is much higher,which brings about the waste of primary energy resources and the pollution of the environment.With the deep study of the gasification technology,Coke Carried-Heat Gasification Coal-Fired Combined Cycle,as the improved system,came into birth in 1996 based on the partial gasification one,At the end of 1997,a new cycle scheme similar to IGCC was created.This paper focuses on several classes combined cycle put forward by Tsinghua University,depending on the plant configuration and carbon conversion,making the solution a viable and attractive option for efficient coal utilization.

  3. Conversion of coal-fired power plants to cogeneration and combined-cycle thermal and economic effectiveness

    CERN Document Server

    Bartnik, Ryszard

    2014-01-01

    This book covers methodology, calculation procedures and tools to support enterprise planning for adapting power stations to cogeneration and combined-cycle forms. It examines the optimum selection of the structure of heat exchangers in a 370 MW power block.

  4. Combined cooling and heating using a gas engine in a supermarket

    Energy Technology Data Exchange (ETDEWEB)

    Maidment, G.G. [South Bank Univ., London (United Kingdom). School of Engineering Systems and Design; Zhao, X.; Riffat, S.B. [Nottingham Univ. (United Kingdom). School of the Built Environment

    2001-07-01

    This paper reports the results of an investigation into the practical and economic viability of an integrated combined heating and cooling system in a supermarket. This system consists of a direct-drive screw compressor, which is powered by a throttle controlled gas engine. The waste heat from the engine is used to provide hot water for space heating and for general usage within the catering and toilet facilities in the supermarket. In this paper, the working principle of the novel system is first described. This details how the gas engine system may be integrated into the typical supermarket. The paper then describes a model, which is used to simulate the energy consumption of the supermarket. This is used to calculate the energy consumed by the conventional system and that used by a number of alternative combined heating and cooling system configurations, which are also described. The additional capital cost of each configuration is estimated and this is used to calculate the payback period. The results show that a payback period of 4.2 years may be achieved with a system that uses approximately 500,000 kWh per annum less primary energy than a conventional system. Finally, comparison between this system and a traditional Combined Heat and Power (CHP) installation is given. (author)

  5. Combined chromatographic and mass spectrometric toolbox for fingerprinting migration from PET tray during microwave heating.

    Science.gov (United States)

    Alin, Jonas; Hakkarainen, Minna

    2013-02-13

    A combined chromatographic and mass spectrometric toolbox was utilized to determine the interactions between poly(ethylene terephthalate) (PET) food packaging and different food simulants during microwave heating. Overall and specific migration was determined by combining weight loss measurements with gas chromatography-mass spectrometry (GC-MS) and electrospray ionization mass spectrometry (ESI-MS). This allowed mapping of low molecular weight migrants in the molecular range up to 2000 g/mol. Microwave heating caused significantly faster migration of cyclic oligomers into ethanol and isooctane as compared to migration during conventional heating at the same temperature. This effect was more significant at lower temperature at which diffusion rates are generally lower. It was also shown that transesterification took place between PET and ethanol during microwave heating, leading to formation of diethyl terephthalate. The detected migrants included cyclic oligomers from dimer to hexamer, in most cases containing extra ethylene glycol units, and oxidized Irgafos 168. ESI-MS combined with CID MS-MS was an excellent tool for structural interpretation of the nonvolatile compounds migrating to the food simulants. The overall migration was below the overall migration limit of 10 mg/dm(2) set by the European commission after 4 h of microwave heating at 100 °C in all studied food simulants.

  6. High-temperature thermocline TES combining sensible and latent heat - CFD modeling and experimental validation

    Science.gov (United States)

    Zavattoni, Simone A.; Geissbühler, Lukas; Barbato, Maurizio C.; Zanganeh, Giw; Haselbacher, Andreas; Steinfeld, Aldo

    2017-06-01

    The concept of combined sensible/latent heat thermal energy storage (TES) has been exploited to mitigate an intrinsic thermocline TES systems drawback of heat transfer fluid outflow temperature reduction during discharging. In this study, the combined sensible/latent TES prototype under investigation is constituted by a packed bed of rocks and a small amount of encapsulated phase change material (AlSi12) as sensible heat and latent heat sections respectively. The thermo-fluid dynamics behavior of the combined TES prototype was analyzed by means of a computational fluid dynamics approach. Due to the small value of the characteristic vessel-to-particles diameter ratio, the effect of radial void-fraction variation, also known as channeling, was accounted for. Both the sensible and the latent heat sections of the storage were modeled as porous media under the assumption of local thermal non-equilibrium (LTNE). The commercial code ANSYS Fluent 15.0 was used to solve the model's constitutive conservation and transport equations obtaining a fairly good agreement with reference experimental measurements.

  7. Expert Meeting Report: Recommendations for Applying Water Heaters in Combination Space and Domestic Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.; Ueno, K.; Bergey, D.; Osser, R.

    2012-07-01

    The topic of this meeting was 'Recommendations For Applying Water Heaters In Combination Space And Domestic Water Heating Systems.' Presentations and discussions centered on the design, performance, and maintenance of these combination systems, with the goal of developing foundational information toward the development of a Building America Measure Guideline on this topic. The meeting was held at the Westford Regency Hotel, in Westford, Massachusetts on 7/31/2011.

  8. Combined Cycle for Power Generation and Refrigeration Using Low Temperature Heat Sources

    OpenAIRE

    Vijay Chauhan; P. Anil Kishan; Sateesh Gedupudi

    2014-01-01

    A combined refrigeration and power cycle, which uses ammonia-water as the working fluid, is proposed by combining Rankine and vapour absorption cycles with an advantage of varying refrigeration capacity to power output ratio. The study investigates the usage of low temperature heat sources for the cycle operation. Results of parametric analysis are presented, which show the scope for optimization. Results of thermodynamic optimization of the cycle for second law efficiency performed using gen...

  9. Analysis of a Coal Fired Combined Cycle with Carried—Heat Gasification

    Institute of Scientific and Technical Information of China (English)

    XuXiangdong; F.N.Fett; 等

    1994-01-01

    In the research of a more effcient,less costly,more environmentally responsible and less technically difficult method for generating electrical power from coal.the Carried-heat Gasification combined Cycle (CGCC) is introduced by Tsinghua University.The high efficiency cycle includes carried-heat partial gasification,compressed air heating in a fluidized bed immersed air heater followed by a combustor and the heat recovery of gas turbine exhaust used as the combustion air for the differential-velocity atmospheric circulating fluidized bed(DFBC),Superheat steam is raised in the DFBC boiler,The comparison of results identifies the causes of performance difference between eight cases,Features of the cycle ensure a high coal conversion efficiency within current state of the art.

  10. HEAT EXCHANGE AND AERODYNAMICS OF THE COMBINED TUBING BUNDLES WITH CROSS INCLINED FINS

    Directory of Open Access Journals (Sweden)

    Knyazyuk V. I

    2013-04-01

    Full Text Available The paper presents results of experimental research and analyses air-side thermal performance of combined tube bundles with cross inclined fins. The empirical correlations for heat transfer and flow friction of tubes with inclined fins at different orientation finned tubes relatively of air flow are presented. The errors of thermal and aerodynamic tests are 3-5% and 9.2%, respectively. The proposed correlations describe an experimental data with a coefficient of determination about 0.979-0.998. The impact of tubes arrangement in a bundle on energy performance of heat exchanger were analyzed using complete and local heat modeling methods at a stationary heat flux. Experimental research indicates that efficiency of inclined fins can be calculated by using the equation for cross rectangular fins with average deviation of ±5 %.

  11. A Novel Absorption Cycle for Combined Water Heating, Dehumidification, and Evaporative Cooling

    Energy Technology Data Exchange (ETDEWEB)

    CHUGH, Devesh [University of Florida, Gainesville; Gluesenkamp, Kyle R [ORNL; Abdelaziz, Omar [ORNL; Moghaddam, Saeed [University of Florida, Gainesville

    2014-01-01

    In this study, development of a novel system for combined water heating, dehumidification, and space evaporative cooling is discussed. Ambient water vapor is used as a working fluid in an open system. First, water vapor is absorbed from an air stream into an absorbent solution. The latent heat of absorption is transferred into the process water that cools the absorber. The solution is then regenerated in the desorber, where it is heated by a heating fluid. The water vapor generated in the desorber is condensed and its heat of phase change is transferred to the process water in the condenser. The condensed water can then be used in an evaporative cooling process to cool the dehumidified air exiting the absorber, or it can be drained if primarily dehumidification is desired. Essentially, this open absorption cycle collects space heat and transfers it to process water. This technology is enabled by a membrane-based absorption/desorption process in which the absorbent is constrained by hydrophobic vapor-permeable membranes. Constraining the absorbent film has enabled fabrication of the absorber and desorber in a plate-and-frame configuration. An air stream can flow against the membrane at high speed without entraining the absorbent, which is a challenge in conventional dehumidifiers. Furthermore, the absorption and desorption rates of an absorbent constrained by a membrane are greatly enhanced. Isfahani and Moghaddam (Int. J. Heat Mass Transfer, 2013) demonstrated absorption rates of up to 0.008 kg/m2s in a membrane-based absorber and Isfahani et al. (Int. J. Multiphase Flow, 2013) have reported a desorption rate of 0.01 kg/m2s in a membrane-based desorber. The membrane-based architecture also enables economical small-scale systems, novel cycle configurations, and high efficiencies. The absorber, solution heat exchanger, and desorber are fabricated on a single metal sheet. In addition to the open arrangement and membrane-based architecture, another novel feature of the

  12. Drought stress had a predominant effect over heat stress on three tomato cultivars subjected to combined

    DEFF Research Database (Denmark)

    Zhou, Rong; Yu, Xiaqing; Ottosen, Carl-Otto

    2017-01-01

    BACKGROUND: Abiotic stresses due to environmental factors could adversely affect the growth and development of crops. Among the abiotic stresses, drought and heat stress are two critical threats to crop growth and sustainable agriculture worldwide. Considering global climate change, incidence...... in 'Arvento' under heat treatment. By comparison, the two heat-tolerant tomatoes were more affected by drought stress compared to 'Arvento' as shown by small stomatal and pore area, decreased sucrose content, ΦPSII (quantum yield of photosystem II), ETR (electron transport rate) and qL (fraction of open PSII...... and relative water content of all cultivars significantly decreased under drought and combined stress as compared to control. The net photosynthesis and starch content were significantly lower under drought and combined stress than control in the three cultivars. Stomata and pore length of the three cultivars...

  13. Hybrid Processing Combining Electrostatic Levitation and Laser Heating: Application to Terrestrial Analogues of Asteroid Materials

    Directory of Open Access Journals (Sweden)

    Paul-François Paradis

    2011-01-01

    Full Text Available Electrostatic levitation combined with laser heating is becoming a mature technique that has been used for several fundamental and applied studies in fluid and materials sciences (synthesis, property determination, solidification studies, atomic dynamic studies, etc.. This is attributable to the numerous processing conditions (containerless, wide heating temperature range, cooling rates, atmospheric compositions, etc. that levitation and radiative heating offer, as well as to the variety of diagnostics tools that can be used. In this paper, we describe the facility, highlighting the combined advantages of electrostatic levitation and laser processing. The various capabilities of the facility are discussed and are exemplified with the measurements of the density of selected iron-nickel alloys taken over the liquid phase.

  14. Environmental Technology Verification Report: Climate Energy freewatt™ Micro-Combined Heat and Power System

    Science.gov (United States)

    The EPA GHG Center collaborated with the New York State Energy Research and Development Authority (NYSERDA) to evaluate the performance of the Climate Energy freewatt Micro-Combined Heat and Power System. The system is a reciprocating internal combustion (IC) engine distributed e...

  15. Accelerated testing of solid oxide fuel cell stacks for micro combined heat and power application

    DEFF Research Database (Denmark)

    Hagen, Anke; Høgh, Jens Valdemar Thorvald; Barfod, Rasmus

    2015-01-01

    State-of-the-art (SoA) solid oxide fuel cell (SOFC) stacks are tested using profiles relevant for use in micro combined heat and power (CHP) units. Such applications are characterised by dynamic load profiles. In order to shorten the needed testing time and to investigate potential acceleration...

  16. Modelling Combined Heat Exchange in the Leading Edge of Perspective Aircraft Wing

    Directory of Open Access Journals (Sweden)

    Kandinsky Roman O.

    2015-01-01

    Full Text Available In this paper gas dynamic numerical modelling of leading edge flow is presented and thermal loading parameters are determined. Numerical modelling of combined radiative and conductive heat transfer of the wing edge is carried out, thermal state of structure is given and the results are analyzed.

  17. Environmental Technology Verification Report: Climate Energy freewatt™ Micro-Combined Heat and Power System

    Science.gov (United States)

    The EPA GHG Center collaborated with the New York State Energy Research and Development Authority (NYSERDA) to evaluate the performance of the Climate Energy freewatt Micro-Combined Heat and Power System. The system is a reciprocating internal combustion (IC) engine distributed e...

  18. Industrial Application of Topology Optimization for Combined Conductive and Convective Heat Transfer Problems

    DEFF Research Database (Denmark)

    Zhou, Mingdong; Alexandersen, Joe; Sigmund, Ole;

    2016-01-01

    This paper presents an industrial application of topology optimization for combined conductive and convective heat transfer problems. The solution is based on a synergy of computer aided design and engineering software tools from Dassault Systemes. The considered physical problem of steady...

  19. Effects of the distribution density of a biomass combined heat and power plant network on heat utilisation efficiency in village-town systems.

    Science.gov (United States)

    Zhang, Yifei; Kang, Jian

    2017-11-01

    The building of biomass combined heat and power (CHP) plants is an effective means of developing biomass energy because they can satisfy demands for winter heating and electricity consumption. The purpose of this study was to analyse the effect of the distribution density of a biomass CHP plant network on heat utilisation efficiency in a village-town system. The distribution density is determined based on the heat transmission threshold, and the heat utilisation efficiency is determined based on the heat demand distribution, heat output efficiency, and heat transmission loss. The objective of this study was to ascertain the optimal value for the heat transmission threshold using a multi-scheme comparison based on an analysis of these factors. To this end, a model of a biomass CHP plant network was built using geographic information system tools to simulate and generate three planning schemes with different heat transmission thresholds (6, 8, and 10 km) according to the heat demand distribution. The heat utilisation efficiencies of these planning schemes were then compared by calculating the gross power, heat output efficiency, and heat transmission loss of the biomass CHP plant for each scenario. This multi-scheme comparison yielded the following results: when the heat transmission threshold was low, the distribution density of the biomass CHP plant network was high and the biomass CHP plants tended to be relatively small. In contrast, when the heat transmission threshold was high, the distribution density of the network was low and the biomass CHP plants tended to be relatively large. When the heat transmission threshold was 8 km, the distribution density of the biomass CHP plant network was optimised for efficient heat utilisation. To promote the development of renewable energy sources, a planning scheme for a biomass CHP plant network that maximises heat utilisation efficiency can be obtained using the optimal heat transmission threshold and the nonlinearity

  20. Effects of a carbon tax on microgrid combined heat and power adoption

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Afzal S.; Marnay, Chris; Edwards, Jennifer L.; Firestone, Ryan M.; Ghosh, Srijay; Stadler, Michael

    2004-11-01

    This paper describes the economically optimal adoption and operation of distributed energy resources (DER) by a hypothetical California microgrid consisting of a group of commercial buildings over an historic test year, 1999. The optimization is conducted using a customer adoption model (DER-CAM) developed at Berkeley Lab and implemented in the General Algebraic Modeling System (GAMS). A microgrid is a semiautonomous grouping of electricity and heat loads interconnected to the existing utility grid (macrogrid) but able to island from it. The microgrid minimizes the cost of meeting its energy requirements (consisting of both electricity and heat loads) by optimizing the installation and operation of DER technologies while purchasing residual energy from the local combined natural gas and electricity utility. The available DER technologies are small-scale generators (< 500 kW), such as reciprocating engines, microturbines, and fuel cells, with or without combined heat and power (CHP) equipment, such as water and space heating and/or absorption cooling. By introducing a tax on carbon emissions, it is shown that if the microgrid is allowed to install CHP-enabled DER technologies, its carbon emissions are mitigated more than without CHP, demonstrating the potential benefits of small-scale CHP technology for climate change mitigation. Reciprocating engines with heat recovery and/or absorption cooling tend to be attractive technologies for the mild southern California climate, but the carbon mitigation tends to be modest compared to purchasing utility electricity because of the predominance of relatively clean central station generation in California.

  1. A Dual-driven Intelligent Combination Control of Heat Pipe Space Cooling System

    Institute of Scientific and Technical Information of China (English)

    LI Yunze; LI Mingmin; LEE Kok Meng

    2012-01-01

    Effective thermal control systems are essential for reliable operation of spacecraft.A dual-driven intelligent combination control strategy is proposed to improve the temperate control and heat flux tracking effects.Both temperature regulation and heat flux tracking errors are employed to generate the final control action; their contributions are adaptively adjusted by a fuzzy fusing policy of control actions.To evaluate the control effects,describe a four-nodal mathematical model for analyzing the dynamic characteristics of the controlled heat pipe space cooling system (HP-SCS) consisting of an aluminum-ammonia heat pipe and a variable-emittance micro-electromechanical-system (MEMS) radiator.This dynamical model calculates the mass flow-rate and condensing pressure of the heat pipe working fluid directly from the systemic nodal temperatures,therefore,it is more suitable for control engineering applications.The closed-loop transient performances of four different control schemes have been numerically investigated.The results conclude that the proposed intelligent combination control scheme not only improves the thermal control effects but also benefits the safe operation of HP-SCS.

  2. Combining several thermal indices to generate a unique heat comfort assessment methodology

    Directory of Open Access Journals (Sweden)

    Wissam EL Hachem

    2015-11-01

    Full Text Available Purpose: The proposed methodology hopes to provide a systematic multi-disciplinary approach to assess the thermal environment while minimizing unneeded efforts. Design/methodology/approach: Different factors affect the perception of the human thermal experience: metabolic rate (biology, surrounding temperatures (heat balance and environmental factors and cognitive treatment (physiology.This paper proposes a combination of different multidisciplinary variables to generate a unique heat comfort assessment methodology. The variables at stake are physiological, biological, and environmental. Our own heat analysis is thoroughly presented and all relevant equations are described. Findings: Most companies are oblivious about potential dangers of heat stress accidents and thus about methods to monitor and prevent them. This methodology enables the company or the concerned individual to conduct a preliminary assessment with minimal wasted resources and time in unnecessary steps whilst providing a guideline for a detailed study with minimal error rates if needed. More so, thermal comfort is an integral part of sound ergonomics practices, which in turn are decisive for the success of any lean six sigma initiative. Research limitations/implications: This methodology requires several full implementations to finalize its design. Originality/value: Most used heat comfort models are inherently uncertain and tiresome to apply. An extensive literature review confirms the need for a uniform assessment methodology that combines the different thermal comfort models such as the Fanger comfort model (PMV, PPD and WGBT since high error rates coupled with tiresome calculations often hinder the thermal assessment process.

  3. Sustainable renewable energy seawater desalination using combined-cycle solar and geothermal heat sources

    KAUST Repository

    Missimer, Thomas M.

    2013-01-01

    Key goals in the improvement of desalination technology are to reduce overall energy consumption, make the process "greener," and reduce the cost of the delivered water. Adsorption desalination (AD) is a promising new technology that has great potential to reduce the need for conventional power, to use solely renewable energy sources, and to reduce the overall cost of water treatment. This technology can desalt seawater or water of even higher salinity using waste heat, solar heat, or geothermal heat. An AD system can operate effectively at temperatures ranging from 55 to 80 °C with perhaps an optimal temperature of 80 °C. The generally low temperature requirement for the feedwater allows the system to operate quite efficiently using an alternative energy source, such as solar power. Solar power, particularly in warm dry regions, can generate a consistent water temperature of about 90 °C. Although this temperature is more than adequate to run the system, solar energy collection only can occur during daylight hours, thereby necessitating the use of heat storage during nighttime or very cloudy days. With increasing capacity, the need for extensive thermal storage may be problematic and could add substantial cost to the development of an AD system. However, in many parts of the world, there are subsurface geothermal energy sources that have not been extensively used. Combining a low to moderate geothermal energy recovery system to an AD system would provide a solution to the thermal storage issue. However, geothermal energy development from particularly Hot Dry Rock is limited by the magnitude of the heat flow required for the process and the thermal conductivity of the rock material forming the heat reservoir. Combining solar and geothermal energy using an alternating 12-h cycle would reduce the probability of depleting the heat source within the geothermal reservoir and provide the most effective use of renewable energy. © 2013 Desalination Publications.

  4. The Integration of Vacuum Brazing into Heat Treatment - A Progressive Combined Process

    Institute of Scientific and Technical Information of China (English)

    Ingo Reinkensmeier; Henkjan Buursen

    2004-01-01

    The continuous constructive challenge to improve the functionality and efficiency of components always results in higher demands on production engineering, against the background of the generally increasing cost pressure. In many cases, you will just succeed in producing competitive and innovative products by combining and coupling of different procedures to an independent (hybrid) technology. The use of hybrid procedures for metal joining and heat treatment of metallic materials finds more and more industrial fields of application. Modern vacuum lines with integrated pressurized gas quenching are considered high-performance and flexible means of production for brazing and heat treatment tasks as well in the turbine industry as in the mould making and tool manufacturing industry. In doing so, the heat treatment is coupled with the brazing cycle in a combined process so that the brazing temperatures and soak times are adapted to the necessary temperatures and times for solution heat treatment and austeniting. This user-oriented article describes on the one hand examples of brazing of turbine components, but above all the practical experience from the plastics processing industry, where the requirement for a high-efficient cooling of injection moulding dies gains more and more importance.The combined procedure "Vacuum Brazing and Hardening" offers plenty of possibilities to produce mould inserts with an efficient tempering system in an economic way.

  5. Floor heating and cooling combined with displacement ventilation: Possibilities and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Causone, Francesco; Corgnati, Stefano P. [TEBE Research Group, Department of Energetics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy); Baldin, Fabio [Department of Applied Physics, University of Padova, via Venezia 1, 35131 Padova (Italy); Olesen, Bjarne W. [ICIEE, Department of Civil Engineering, Technical University of Denmark, Nils Koppels Alle Building 402, 2800 Kgs. Lyngby (Denmark)

    2010-12-15

    Design guidelines envisage that floor heating can be used together with displacement ventilation (DV), provided that the supply air is not overly heated before it can reach heat and contaminant sources. If this is not controlled a mixing flow pattern could occur in the room. The use of floor cooling with DV is also considered possible, although draught risk at ankle level and vertical air temperature differences must be controlled carefully, because they could increase. Few studies on these topics were found in the literature. An indoor environmental chamber was set up to obtain measurements aimed at analysing the possibilities and limitations of combining floor heating/cooling with DV. Air temperature profiles, air velocity profiles, surface temperatures and ventilation effectiveness were measured under different environmental conditions that may occur in practice. These values were compared to equivalent temperature measurements obtained using a thermal manikin. The measurements show that floor heating can be used with DV, obtaining high ventilation effectiveness values. A correlation between the floor heating capacity and the air temperature profile in the room was found. Measurements showed that floor cooling does not increase draught risk at ankle level, although it does increase vertical air temperature differences. (author)

  6. Industrial Application of Topology Optimization for Combined Conductive and Convective Heat Transfer Problems

    DEFF Research Database (Denmark)

    Zhou, Mingdong; Alexandersen, Joe; Sigmund, Ole

    2016-01-01

    This paper presents an industrial application of topology optimization for combined conductive and convective heat transfer problems. The solution is based on a synergy of computer aided design and engineering software tools from Dassault Systemes. The considered physical problem of steady......-state heat transfer under convection is simulated using SIMULIA-Abaqus. A corresponding topology optimization feature is provided by SIMULIA-Tosca. By following a standard workflow of design optimization, the proposed solution is able to accommodate practical design scenarios and results in efficient...

  7. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    Florian Heberle

    2014-07-01

    Full Text Available We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC in a combined heat and power generation (CHP case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency as well as economic parameters show that hybrid power plants are more efficient compared to conventional CHP concepts or separate use of the energy sources.

  8. Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

    2014-01-01

    production. An exergy analysis is carried out for a modelled polygeneration system in which lignocellulosic ethanol production based on hydrothermal pretreatment is integrated in an existing combined heat and power (CHP) plant. The ethanol facility is driven by steam extracted from the CHP unit when feasible...... district heating production in the ethanol facility. The results suggest that the efficiency of integrating lignocellulosic ethanol production in CHP plants is highly dependent on operation, and it is therefore suggested that the expected operation pattern of such polygeneration system is taken...

  9. Cooling load optimization of an irreversible refrigerator with combined heat transfer

    Directory of Open Access Journals (Sweden)

    M. El Haj Assad

    2013-01-01

    Full Text Available In this work a mathematical model to study the performance of an irreversible refrigerator has been presented with the consideration of heat exchange by combined convection and radiation. The external irreversibility effects due to finite rate heat transfer as well as the effects of internal dissipations have been considered in the analysis. The relation between the cooling load and the coefficient of performance of the refrigerator has been derived. Furthermore an expression for the maximum cooling rate has been derived. The parameters that affect the cooling load have been investigated. The cooling load has been discussed and the effect of internal irreversibility has been investigated.

  10. A Novel Approach for Cooling Electronics Using a Combined Heat Pipe and Thermoelectric Module

    Directory of Open Access Journals (Sweden)

    Banjerd Saengchandr

    2009-01-01

    Full Text Available The development of effective cooling systems for microprocessors, specifically for CPU and other computer chips, is greatly important due to growth of high speed performance chips, which operate at elevated heat rates. The same issues apply for adjacent units including RAM and HDD also contributing to overall generation of heat inside computer. Problem statement: Conventional cooling system for desktop PC has many problems, especially cooling performance. Lifespan of devices and reliable operation are largely dependent on junction temperature. Total power dissipation of recently introduced, new generation microprocessors had been increasing rapidly, pushing desktop system cooling technology close to its limits. Approach: Present research focused on a system for removal of dissipated heat that combined the advantages of heat pipe and thermoelectric modules. Proposed research presented a numerical analysis of a novel cooling system for electronics. Configuration studied concerns microprocessors and other computer ships. Simulations performed in this research were based on use of computational fluid dynamics and results obtained in terms of cooling efficiencies were compared to those of the traditional cooling. Heat resistance and temperature of each component were investigated in this modeling. Results: Lowest core temperature was found below 75°C and total thermal resistance of cooling system is 0.095°C/W. Conclusion/Recommendations: Proposed cooling systems had sufficient capacity for cooling 200 W heat dissipation. Temperature of proposed cooling system is lower than both existing cooling systems. Temperature of all components, CPU, heat pipe, TEC and heat sink were below 75°C. Thermal resistance characteristic of a cooling system had a major effect on cooling performance.

  11. A new hybrid method--combined heat flux method with Monte-Carlo method to analyze thermal radiation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new hybrid method, Monte-Carlo-Heat-Flux (MCHF) method, was presented to analyze the radiative heat transfer of participating medium in a three-dimensional rectangular enclosure using combined the Monte-Carlo method with the heat flux method. Its accuracy and reliability was proved by comparing the computational results with exact results from classical "Zone Method".

  12. The CO2 Reduction Potential of Combined Heat and Power in California's Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, Michael; Marnay, Chris; Cardoso, Goncalo; Lipman, Tim; Megel, Olivier; Ganguly, Srirupa; Siddiqui, Afzal; Lai, Judy

    2009-11-16

    The Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) is working with the California Energy Commission (CEC) to determine the potential role of commercial sector distributed generation (DG) with combined heat and power (CHP) capability deployment in greenhouse gas emissions (GHG) reductions. CHP applications at large industrial sites are well known, and a large share of their potential has already been harvested. In contrast, relatively little attention has been paid to the potential of medium-sized commercial buildings, i.e., ones with peak electric loads ranging from 100 kW to 5 MW. We examine how this sector might implement DG with CHP in cost minimizing microgrids that are able to adopt and operate various energy technologies, such as solar photovoltaics (PV), on-site thermal generation, heat exchangers, solar thermal collectors, absorption chillers, and storage systems. We apply a mixed-integer linear program (MILP) that minimizes a site's annual energy costs as its objective. Using 138 representative mid-sized commercial sites in California (CA), existing tariffs of three major electricity distribution ultilities plus a natural gas company, and performance data of available technology in 2020, we find the GHG reduction potential for this CA commercial sector segment, which represents about 35percent of total statewide commercial sector sales. Under the assumptions made, in a reference case, this segment is estimated to be capable of economically installing 1.4 GW of CHP, 35percent of the California Air Resources Board (CARB) statewide 4 GW goal for total incremental CHP deployment by 2020. However, because CARB's assumed utilization is far higherthan is found by the MILP, the adopted CHP only contributes 19percent of the CO2 target. Several sensitivity runs were completed. One applies a simple feed-in tariff similar to net metering, and another includes a generous self-generation incentive program (SGIP) subsidy for fuel cells. The feed

  13. Optimization of systems with the combination of ground-source heat pump and solar collectors in dwellings

    DEFF Research Database (Denmark)

    Kjellsson, Elisabeth; Hellström, Göran; Perers, Bengt

    2010-01-01

    The use of ground-source heat pumps for heating and domestic hot water in dwellings is common in Sweden. The combination with solar collectors has been introduced to reduce the electricity demand in the system. In order to analyze different systems with combinations of solar collectors and ground......-source heat pumps, computer simulations have been carried out with the simulation program TRNSYS. Large differences were found between the system alternatives. The optimal design is when solar heat produces domestic hot water during summertime and recharges the borehole during wintertime. The advantage...... is related to the rate of heat extraction from the borehole as well as the overall design of the system. The demand of electricity may increase with solar recharging, because of the increased operating time of the circulation pumps. Another advantage with solar heat in combination with heat pumps is when...

  14. Modeling and optimization of a heat-pump-assisted high temperature proton exchange membrane fuel cell micro-combined-heat-and-power system for residential applications

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Kær, Søren Knudsen; Nielsen, Mads Pagh

    2015-01-01

    In this study a micro-combined-heat-and-power (micro-CHP) system is coupled to a vapor-compression heat pump to fulfill the residential needs for heating (space heating and water heating) and electricity in detached single-family households in Denmark. Such a combination is assumed to be attractive...... for application, since both fuel cell technology and electric heat pumps are found to be two of the most efficient technologies for generation/conversion of useful energy. The micro-CHP system is fueled with natural gas and includes a fuel cell stack, a fuel processor and other auxiliary components. The micro....... The variational loads are considered from full to quarter load, and the micro-CHP system is optimized in terms of operating thermophysical parameters for every different load. The results clearly indicate the capability of the proposed system to perform efficiently throughout all necessary load changes to fulfill...

  15. Measurement of heat treatment induced residual stresses by using ESPI combined with hole-drilling method

    Institute of Scientific and Technical Information of China (English)

    Jie Cheng; Si-Young Kwak; Ho-Young Hwang

    2010-01-01

    In this study,residual stresses in heat treated specimen were measured by using ESPI(Electronic Speckle-Pattern Interferometry)combined with the hole-drilling method.The specimen,made of SUS 304austenitic stainless steel,was quenched and water cooled to room temperature.Numerical simulation using a hybrid FDM/FEM package was also carried out to simulate the heat treatment process.As a result,the thermal stress fields were obtained from both the experiment and the numerical simulation.By comparision of stress fields,results from the experimental method and numerical simulation well agreed to each other,therefore,it is proved that the presented experimental method is applicable and reliable for heat treatment induced residual stress measurement.

  16. Testing for cross-subsidisation in the combined heat and power generation sector

    DEFF Research Database (Denmark)

    Amundsen, Eirik S; Andersen, Per; Jensen, Frank

    2011-01-01

    In this paper we examine cross-subsidisation among combined heat and power producers in Denmark.Information on stand-alone costs for heat generation allows us to empirically compare the Faulhaber tests,tests with an upper bound on stand-alone costs (the Palmer tests) and the fully distributed cost...... test (FDC). All tests indicate a substantial amount of cross-subsidisation from heat generation to power generation. It is shown that the FDC test is closer to that of the Faulhaber tests in its results than the Palmer tests. Thus as the Faulhaber tests are considered in the literature...... to be the theoretically correct tests, the FDC test is shown to be the best approximation for tests of cross-subsidisation for this specific sector....

  17. Combined effect of natural convection and non-gray gas radiation with partial heating

    Indian Academy of Sciences (India)

    A MAZGAR; F BEN NEJMA

    2016-07-01

    The present paper reports numerical results of combined effects of non-gray gas radiation and natural convection between two vertical plates with partial heating at walls. The plates are symmetrical and made of two equal zones alternately isotherm and insulated. The idea is to predict that thermal radiation will attenuate the difference pre-established in the literature, between choosing a partial heating from the top and the bottom of the wall. Computations are carried out to establish flow and temperature fields of the fluid in the enclosure. The effect of enclosure dimensions and boundary conditions are analyzed. Using the computed temperature fields, the mean Nusselt number is calculated. The results show that there is no major influence of two-dimensional radiation to reduce the difference between the reported top and bottom heating for the chosen gas.

  18. Dynamic modeling and evaluation of solid oxide fuel cell - combined heat and power system operating strategies

    Science.gov (United States)

    Nanaeda, Kimihiro; Mueller, Fabian; Brouwer, Jacob; Samuelsen, Scott

    Operating strategies of solid oxide fuel cell (SOFC) combined heat and power (CHP) systems are developed and evaluated from a utility, and end-user perspective using a fully integrated SOFC-CHP system dynamic model that resolves the physical states, thermal integration and overall efficiency of the system. The model can be modified for any SOFC-CHP system, but the present analysis is applied to a hotel in southern California based on measured electric and heating loads. Analysis indicates that combined heat and power systems can be operated to benefit both the end-users and the utility, providing more efficient electric generation as well as grid ancillary services, namely dispatchable urban power. Design and operating strategies considered in the paper include optimal sizing of the fuel cell, thermal energy storage to dispatch heat, and operating the fuel cell to provide flexible grid power. Analysis results indicate that with a 13.1% average increase in price-of-electricity (POE), the system can provide the grid with a 50% operating range of dispatchable urban power at an overall thermal efficiency of 80%. This grid-support operating mode increases the operational flexibility of the SOFC-CHP system, which may make the technology an important utility asset for accommodating the increased penetration of intermittent renewable power.

  19. 首台300MW汽轮机循环水供热改造技术与经济指标分析%Transformation Technology and Economic Indicators Analysis of the First 300MW Steam Turbine Supplying Heat Using High-temperature Circulating Water

    Institute of Scientific and Technical Information of China (English)

    成渫畏; 王学栋; 宋昂

    2016-01-01

    This paper introduces the technology and content of the first subcritical 300MW steam turbine transforma-tion using high-temperature circulating water for direct heating, and illustrates the similarities and differences with the 135MW stage units. On the basis of transformation technology of double back-pressure and dual rotor switch on 135MW stage units, Technical problems that commonality transformation of dual low-pressure cylinder, feeding water pump turbine transformation, and condensate polishing treatment system transformation have been solved on 300MW turbine unit to achieve direct heating using high-temperature circulating water. After transformation, the performance test results show that economic indicators of the unit have reached design values. Its energy-saving effect is remarkable.%介绍了首台亚临界300MW汽轮机高温循环水供热改造技术和改造内容,并阐述了与135MW等级机组改造的异同点。在135MW等级机组双背压双转子互换改造技术的基础上,300MW汽轮机解决了双层低压缸通用性改造、给水泵小汽轮机改造以及凝结水精处理系统改造等关键技术难题,成功实施了高温循环水直接供热技术改造。由改造后性能考核试验结果得知,机组各项经济指标达到设计值,节能效果显著。

  20. Impacts of New EU and Czech Environmental Legislation on Heat and Electricity Prices of Combined Heat and Power Sources in the Czech Republic

    Directory of Open Access Journals (Sweden)

    J. Vecka

    2011-01-01

    Full Text Available In my economic model I calculate the impact of the new EU ETS Directive, the Industrial Emissions Directive and the new air protection law on future heat and electricity prices for combined heat and power sources. I discover that there will be a significant increase in heat and electricity prices, especially because of the implementation of new so-called benchmark tools for allocating allowances. The main problem of large heat producers in this respect is loss of competitiveness on the heat market due to emerging stricter environmental legislation, which is not applied to competitors on the heat market (smaller heat sources. There is also lack of clarity about the modalities for allocating free allowances, and about the future development of the whole carbon market (the future European allowance price.

  1. Design for micro-combined cooling, heating and power systems stirling engines and renewable power systems

    CERN Document Server

    2015-01-01

    ‘Design for Micro-Combined Cooling, Heating & Power Systems’ provides a manual for the technical and structural design of systems for supplying decentralised energy in residential buildings. It presents the micro-combined cooling, heating & power systems Stirling engines & renewable energy sources (mCCHP-SE-RES) systems in an accessible manner both for the public at large, and for professionals who conceive, design or commercialise such systems or their components.  The high performance levels of these systems are demonstrated within the final chapter by the results of an experiment in which a house is equipped with a mCCHP-SE-RES system. The reader is also familiarized with the conceptual, technical and legal aspects of modern domestic energy systems; the components that constitute these systems; and advanced algorithms for achieving the structural and technical design of such systems. In residential buildings, satisfying demands of durable development has gradually evolved from necessity to...

  2. Combined effect of ohmic heating and enzyme assisted aqueous extraction process on soy oil recovery.

    Science.gov (United States)

    Pare, Akash; Nema, Anurag; Singh, V K; Mandhyan, B L

    2014-08-01

    This research describes a new technological process for soybean oil extraction. The process deals with the combined effect of ohmic heating and enzyme assisted aqueous oil extraction process (EAEP) on enhancement of oil recovery from soybean seed. The experimental process consisted of following basic steps, namely, dehulling, wet grinding, enzymatic treatment, ohmic heating, aqueous extraction and centrifugation. The effect of ohmic heating parameters namely electric field strength (EFS), end point temperature (EPT) and holding time (HT) on aqueous oil extraction process were investigated. Three levels of electric field strength (i.e. OH600V, OH750V and OH900V), 3 levels of end point temperature (i.e. 70, 80 and 90 °C) and 3 levels of holding time (i.e. 0, 5 and 10 min.) were taken as independent variables using full factorial design. Percentage oil recovery from soybean by EAEP alone and EAEP coupled with ohmic heating were 53.12 % and 56.86 % to 73 % respectively. The maximum oil recovery (73 %) was obtained when the sample was heated and maintained at 90 °C using electric field strength of OH600V for a holding time of 10 min. The free fatty acid (FFA) of the extracted oil (i.e. in range of 0.97 to 1.29 %) was within the acceptable limit of 3 % (oleic acid) and 0.5-3 % prescribed respectively by PFA and BIS.

  3. Heat Transfer Computations of Internal Duct Flows With Combined Hydraulic and Thermal Developing Length

    Science.gov (United States)

    Wang, C. R.; Towne, C. E.; Hippensteele, S. A.; Poinsatte, P. E.

    1997-01-01

    This study investigated the Navier-Stokes computations of the surface heat transfer coefficients of a transition duct flow. A transition duct from an axisymmetric cross section to a non-axisymmetric cross section, is usually used to connect the turbine exit to the nozzle. As the gas turbine inlet temperature increases, the transition duct is subjected to the high temperature at the gas turbine exit. The transition duct flow has combined development of hydraulic and thermal entry length. The design of the transition duct required accurate surface heat transfer coefficients. The Navier-Stokes computational method could be used to predict the surface heat transfer coefficients of a transition duct flow. The Proteus three-dimensional Navier-Stokes numerical computational code was used in this study. The code was first studied for the computations of the turbulent developing flow properties within a circular duct and a square duct. The code was then used to compute the turbulent flow properties of a transition duct flow. The computational results of the surface pressure, the skin friction factor, and the surface heat transfer coefficient were described and compared with their values obtained from theoretical analyses or experiments. The comparison showed that the Navier-Stokes computation could predict approximately the surface heat transfer coefficients of a transition duct flow.

  4. Heat flux reduction mechanism induced by a combinational opposing jet and cavity concept in supersonic flows

    Science.gov (United States)

    Huang, Wei; Jiang, Yan-ping; Yan, Li; Liu, Jun

    2016-04-01

    The thermal protection on the surface of hypersonic vehicles attracts an increasing attention worldwide, especially when the vehicle enters the atmosphere at high speed. In the current study, the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the Menter's shear stress transport (SST) model have been employed to investigate the heat flux reduction mechanism induced by the variations of the cavity configuration, the jet pressure ratio and the injectant molecular weight in the combinational opposing jet and cavity concept. The length of the cavity is set to be 6 mm, 8 mm and 10 mm in order to make sure that the cavity configuration is the "open" cavity, and the jet pressure ratio is set to be 0.4, 0.6 and 0.8 in order to make sure that the flow field is steady. The injectant is set to be nitrogen and helium. The obtained results show that the aft angle of the cavity only has a slight impact on the heat flux reduction, and the heat flux peak decreases with the decrease of the length of the cavity. The design of the thermal protection system for the hypersonic blunt body is a multi-objective design exploration problem, and the heat flux distribution depends on the jet pressure ratio, the aft wall of the cavity and the injectant molecular weight. The heat flux peak decreases with the increase of the jet pressure ratio when the aft angle of the cavity is large enough, and this value is 45°.

  5. A combined study of heat and mass transfer in an infant incubator with an overhead screen.

    Science.gov (United States)

    Ginalski, Maciej K; Nowak, Andrzej J; Wrobel, Luiz C

    2007-06-01

    The main objective of this study is to investigate the major physical processes taking place inside an infant incubator, before and after modifications have been made to its interior chamber. The modification involves the addition of an overhead screen to decrease radiation heat losses from the infant placed inside the incubator. The present study investigates the effect of these modifications on the convective heat flux from the infant's body to the surrounding environment inside the incubator. A combined analysis of airflow and heat transfer due to conduction, convection, radiation and evaporation has been performed, in order to calculate the temperature and velocity fields inside the incubator before and after the design modification. Due to the geometrical complexity of the model, computer-aided design (CAD) applications were used to generate a computer-based model. All numerical calculations have been performed using the commercial computational fluid dynamics (CFD) package FLUENT, together with in-house routines used for managing purposes and user-defined functions (UDFs) which extend the basic solver capabilities. Numerical calculations have been performed for three different air inlet temperatures: 32, 34 and 36 degrees C. The study shows a decrease of the radiative and convective heat losses when the overhead screen is present. The results obtained were numerically verified as well as compared with results available in the literature from investigations of dry heat losses from infant manikins.

  6. Optical clearing agent perfusion enhancement via combination of microneedle poration, heating and pneumatic pressure

    OpenAIRE

    Damestani, Y; Melakeberhan, B; Rao, MP; Aguilar, G.

    2014-01-01

    Background and Objective Optical clearing agents (OCAs) have shown promise for increasing the penetration depth of biomedical lasers by temporarily decreasing optical scattering within the skin. However, their translation to the clinic has been constrained by lack of practical means for effectively perfusing OCA within target tissues in vivo. The objective of this study was to address this limitation through combination of a variety of techniques to enhance OCA perfusion, including heating of...

  7. Determining Reliability Parameters for a Closed-Cycle Small Combined Heat and Power Plant

    Directory of Open Access Journals (Sweden)

    Vysokomorny Vladimir S.

    2016-01-01

    Full Text Available The paper provides numerical values of the reliability parameters for independent power sources within the ambient temperature and output power range corresponding to the operation under the climatic conditions of Eastern Siberia and the Far East of the Russian Federation. We have determined the optimal values of the parameters necessary for the reliable operation of small CHP plants (combined heat and power plants providing electricity for isolated facilities.

  8. A new hybrid algorithm for solving transient combined conduction radiation heat transfer problems

    Directory of Open Access Journals (Sweden)

    Chaabane Raoudha

    2011-01-01

    Full Text Available A new algorithm based on the lattice Boltzmann method (LBM and the Control Volume Finite Element Method (CVFEM is proposed as an hybrid solver for two dimensional transient conduction and radiation heat transfer problems in an optically emitting, absorbing and scattering medium. The LBM was used to solve the energy equation and the CVFEM was used to compute the radiative information. The advantages of the proposed methodology is to avoid problems that confronted when previous techniques are used to predict radiative heat transfer, essentially, in complex geometries and when there is scattering and/or non-black boundaries surfaces. This method combination, which is applied for the first time to solve this unsteady combined mode of heat transfer, has been found to accurately predict the effects of various thermo-physical parameters such as the scattering albedo, the conduction-radiation parameter and the extinction coefficient on temperature distribution. The results of the LBM-CVFEM combination were found to be in excellent agreement with the LBM-CDM (Collapsed Dimension Methodthis proposed numerical approach include, among others, simple implementation on a computer, accurate CPU time, and capability of stable simulation.

  9. Application of combined heat-and-power and absorption cooling in a supermarket

    Energy Technology Data Exchange (ETDEWEB)

    Maidment, G.G. [South Bank Univ., School of Engineering Systems and Design, London (United Kingdom); Zhao, X. [Taiyuan Univ. of Technology, Dept. of Environmental Engineering, Shanxi (China); Riffat, S.B. [Nottingham Univ., School of the Built Environment, Nottingham (United Kingdom); Prosser, G. [Stal Refrigeration Ltd., Uxbridge (United Kingdom)

    1999-07-01

    In recent years, it has become standard practice to consider Combined Heat-and-Power (CHP) systems for commercial buildings. CHPs schemes are used, because they are an efficient means of power generation. Unlike conventional power stations, they produce electricity locally and thus minimise the distribution losses, however, they also utilise the waste heat from the generation processes. In applications where there is a combined heating and electricity requirement, a very efficient means of energy production is achieved compared to the conventional methods of providing heating and electricity. With new initiatives from the UK government on reduced energy-use, energy-efficient systems such as CHP have been considered for new applications. This paper summarises the results of an investigation into the viability of CHP systems in supermarkets. The viability of conventional CHP has been theoretically investigated using a mathematical model of a typical supermarket. This has demonstrated that a conventional CHP system may be practically applied. It has also been shown that compared to the traditional supermarket design, the proposed CHP systems will use slightly less primary energy and the running costs will be significantly reduced. An attractive payback period of approximately 4 years has been calculated. Despite these advantages considerable quantity of heat is rejected to atmosphere with this system and this is because the configuration utilises the heat mainly for space heating which is only required for part of the year. To increase the utilisation time, a novel CHP/absorption system has been investigated. This configuration provides a continuous demand of the waste heat, which is used to drive an absorption chiller that refrigerates propylene glycol to -10degC for cooling the chilled-food cabinets. The results show this concept to be theoretically practical. the systems has also been shown to be extremely efficient, with primary energy savings of approximately 20

  10. Optimal selection of on-site generation with combined heat andpower applications

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Afzal S.; Marnay, Chris; Bailey, Owen; HamachiLaCommare, Kristina

    2004-11-30

    While demand for electricity continues to grow, expansion of the traditional electricity supply system, or macrogrid, is constrained and is unlikely to keep pace with the growing thirst western economies have for electricity. Furthermore, no compelling case has been made that perpetual improvement in the overall power quality and reliability (PQR)delivered is technically possible or economically desirable. An alternative path to providing high PQR for sensitive loads would generate close to them in microgrids, such as the Consortium for Electricity Reliability Technology Solutions (CERTS) Microgrid. Distributed generation would alleviate the pressure for endless improvement in macrogrid PQR and might allow the establishment of a sounder economically based level of universal grid service. Energy conversion from available fuels to electricity close to loads can also provide combined heat and power (CHP) opportunities that can significantly improve the economics of small-scale on-site power generation, especially in hot climates when the waste heat serves absorption cycle cooling equipment that displaces expensive on-peak electricity. An optimization model, the Distributed Energy Resources Customer Adoption Model (DER-CAM), developed at Berkeley Lab identifies the energy bill minimizing combination of on-site generation and heat recovery equipment for sites, given their electricity and heat requirements, the tariffs they face, and a menu of available equipment. DER-CAM is used to conduct a systemic energy analysis of a southern California naval base building and demonstrates atypical current economic on-site power opportunity. Results achieve cost reductions of about 15 percent with DER, depending on the tariff.Furthermore, almost all of the energy is provided on-site, indicating that modest cost savings can be achieved when the microgrid is free to select distributed generation and heat recovery equipment in order to minimize its over all costs.

  11. 12MW Horns Rev experiment

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Peña, A.; Mikkelsen, Torben

    The 12MW project with the full title ‘12 MW wind turbines: the scientific basis for their operation at 70 to 270 m height offshore’ has the goal to experimentally investigate the wind and turbulence characteristics between 70 and 270 m above sea level and thereby establish the scientific basis...... relevant for the next generation of huge 12 MW wind turbines operating offshore. The report describes the experimental campaign at the Horns Rev offshore wind farm at which observations from Doppler Laser LIDAR and SODAR were collected from 3 May to 24 October 2006. The challenges for mounting...... profile. Further studies on this part of the work are on-going. Technical detail on LIDAR and SODAR are provided as well as theoretical work on turbulence and atmospheric boundary layer flow. Selected results from the experimental campaign are reported....

  12. Combined facial heating and inhalation of hot air do not alter thermoeffector responses in humans.

    Science.gov (United States)

    Wingo, Jonathan E; Low, David A; Keller, David M; Kimura, Kenichi; Crandall, Craig G

    2015-09-01

    The influence of thermoreceptors in human facial skin on thermoeffector responses is equivocal; furthermore, the presence of thermoreceptors in the respiratory tract and their involvement in thermal homeostasis has not been elucidated. This study tested the hypothesis that hot air directed on the face and inhaled during whole body passive heat stress elicits an earlier onset and greater sensitivity of cutaneous vasodilation and sweating than that directed on an equal skin surface area away from the face. Six men and two women completed two trials separated by ∼1 wk. Participants were passively heated (water-perfused suit; core temperature increase ∼0.9°C) while hot air was directed on either the face or on the lower leg (counterbalanced). Skin blood flux (laser-Doppler flowmetry) and local sweat rate (capacitance hygrometry) were measured at the chest and one forearm. During hot-air heating, local temperatures of the cheek and leg were 38.4 ± 0.8°C and 38.8 ± 0.6°C, respectively (P = 0.18). Breathing hot air combined with facial heating did not affect mean body temperature onsets (P = 0.97 and 0.27 for arm and chest sites, respectively) or slopes of cutaneous vasodilation (P = 0.49 and 0.43 for arm and chest sites, respectively), or the onsets (P = 0.89 and 0.94 for arm and chest sites, respectively), or slopes of sweating (P = 0.48 and 0.65 for arm and chest sites, respectively). Based on these findings, respiratory tract thermoreceptors, if present in humans, and selective facial skin heating do not modulate thermoeffector responses during passive heat stress. Copyright © 2015 the American Physiological Society.

  13. Combined use of solar heat and cogeneration - a perspective for district heating?; Kombinierter Einsatz von solarer Waerme und Kraft-Waerme-Kopplung - eine Perspektive fuer die Nahwaerme?

    Energy Technology Data Exchange (ETDEWEB)

    Entress, J. [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), Stuttgart (Germany). Abt. Systemanalyse und Technikbewertung; Steinborn, F. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany). Fachgebiet Systemanalyse

    1998-02-01

    With Cogeneration of Heat and Power (CHP), climate-endangering CO{sub 2}-emissions can be reduced singificantly. The heat produced can be delivered at prices comparable to those of conventionally produced heat. With solar district heating, yet higher CO{sub 2}-savings are possible but at higher cost. Promising is a combination of CHP and solar district heating: The heat storage of the solar system can be used to level out heat demand, leading to smooth CHP operation, while heat generated by CHP can be used to substitute for low irradiation during the winter period. However, calculations together with simulation and optimization indicate that combining CHP and solar district heating is not the optimal solution in all cases. (orig.) [Deutsch] Der Einsatz von Blockheizkraftwerken (BHKW) kann zu einer deutlichen Reduzierung der klimagefaehrdenden CO{sub 2}-Emissionen beitragen. Dabei kann die ausgekoppelte Waerme etwa zum gleichen Preis wie konventionell erzeugte Waerme abgegeben werden. Hoehere CO{sub 2}-Einsparungen lassen sich hingegen mit solarer Nahwaerme erzielen, allerdings zu hoeheren Kosten. Eine Kombination dieser beiden Waermetechniken verspricht Vorteile: Einerseits kann der Waermespeicher des Solarsystems auch zum Ausgleich von Lastspitzen beim Betrieb des BHKW`s genutzt werden. Andererseits kann die waehrend der einstrahlungsarmen Wintermonate fehlende solare Waerme durch das BHKW erzeugt werden. Detaillierte Simulations- und Optimierungsrechnungen zeigen jedoch, dass eine Kombination dieser Waermetechniken nicht immer empfehlenswert ist. (orig.)

  14. Modulation of Antioxidant Defense System Is Associated with Combined Drought and Heat Stress Tolerance in Citrus

    Directory of Open Access Journals (Sweden)

    Sara I. Zandalinas

    2017-06-01

    Full Text Available Drought and high temperatures are two major abiotic stress factors that often occur simultaneously in nature, affecting negatively crop performance and yield. Moreover, these environmental challenges induce oxidative stress in plants through the production of reactive oxygen species (ROS. Carrizo citrange and Cleopatra mandarin are two citrus genotypes with contrasting ability to cope with the combination of drought and heat stress. In this work, a direct relationship between an increased antioxidant activity and stress tolerance is reported. According to our results, the ability of Carrizo plants to efficiently coordinate superoxide dismutase (SOD, ascorbate peroxidase (APX, catalase (CAT, and glutathione reductase (GR activities involved in ROS detoxification along with the maintenance of a favorable GSH/GSSG ratio could be related to their relative tolerance to this stress combination. On the other hand, the increment of SOD activity and the inefficient GR activation along with the lack of CAT and APX activities in Cleopatra plants in response to the combination of drought and heat stress, could contribute to an increased oxidative stress and the higher sensibility of this citrus genotype to this stress combination.

  15. Guide to Combined Heat and Power Systems for Boiler Owners and Operators

    Energy Technology Data Exchange (ETDEWEB)

    Oland, CB

    2004-08-19

    Combined heat and power (CHP) or cogeneration is the sequential production of two forms of useful energy from a single fuel source. In most CHP applications, chemical energy in fuel is converted to both mechanical and thermal energy. The mechanical energy is generally used to generate electricity, while the thermal energy or heat is used to produce steam, hot water, or hot air. Depending on the application, CHP is referred to by various names including Building Cooling, Heating, and Power (BCHP); Cooling, Heating, and Power for Buildings (CHPB); Combined Cooling, Heating, and Power (CCHP); Integrated Energy Systems (IES), or Distributed Energy Resources (DER). The principal technical advantage of a CHP system is its ability to extract more useful energy from fuel compared to traditional energy systems such as conventional power plants that only generate electricity and industrial boiler systems that only produce steam or hot water for process applications. By using fuel energy for both power and heat production, CHP systems can be very energy efficient and have the potential to produce electricity below the price charged by the local power provider. Another important incentive for applying cogeneration technology is to reduce or eliminate dependency on the electrical grid. For some industrial processes, the consequences of losing power for even a short period of time are unacceptable. The primary objective of the guide is to present information needed to evaluate the viability of cogeneration for new or existing industrial, commercial, and institutional (ICI) boiler installations and to make informed CHP equipment selection decisions. Information presented is meant to help boiler owners and operators understand the potential benefits derived from implementing a CHP project and recognize opportunities for successful application of cogeneration technology. Topics covered in the guide follow: (1) an overview of cogeneration technology with discussions about benefits

  16. Integrated solar combined cycles using gas turbines with partial recuperation and solar integration at different pressure levels

    Science.gov (United States)

    Rovira, Antonio; Sánchez, Consuelo; Fernández, Santiago; Muñoz, Marta; Barbero, Rubén

    2017-06-01

    This work studies and compares two alternatives to improve the solar-to-electricity energy conversion efficiency in integrated solar combined cycle power plants (ISCC), which are based on the use of combined cycles including partial recuperative gas turbines. Each alternative has been integrated into dual and triple pressure levels with reheat heat recovery steam generators (HRSG). Partial recuperation conveys lower heat recovery at the steam generator than in conventional plants, because each MW exchanged in the recuperator is not available at the HRSG. This thermal power decrease at the HRSG may be overcome by the integration of solar energy that is implemented using parabolic trough collectors. Moreover, with such an implementation each solar thermal MW integrated allows a MW of heat recuperation and, thus a MW of fossil fuel saving, thus the solar heat-to-electricity energy conversion rate may reach values up to 50 %, which makes the proposal interesting.

  17. Sizing Combined Heat and Power Units and Domestic Building Energy Cost Optimisation

    Directory of Open Access Journals (Sweden)

    Dongmin Yu

    2017-06-01

    Full Text Available Many combined heat and power (CHP units have been installed in domestic buildings to increase energy efficiency and reduce energy costs. However, inappropriate sizing of a CHP may actually increase energy costs and reduce energy efficiency. Moreover, the high manufacturing cost of batteries makes batteries less affordable. Therefore, this paper will attempt to size the capacity of CHP and optimise daily energy costs for a domestic building with only CHP installed. In this paper, electricity and heat loads are firstly used as sizing criteria in finding the best capacities of different types of CHP with the help of the maximum rectangle (MR method. Subsequently, the genetic algorithm (GA will be used to optimise the daily energy costs of the different cases. Then, heat and electricity loads are jointly considered for sizing different types of CHP and for optimising the daily energy costs through the GA method. The optimisation results show that the GA sizing method gives a higher average daily energy cost saving, which is 13% reduction compared to a building without installing CHP. However, to achieve this, there will be about 3% energy efficiency reduction and 7% input power to rated power ratio reduction compared to using the MR method and heat demand in sizing CHP.

  18. Combined heat and power generation with a HCPV system at 2000 suns

    Science.gov (United States)

    Paredes, Filippo; Montagnino, Fabio M.; Salinari, Piero; Bonsignore, Gaetano; Milone, Sergio; Agnello, Simonpietro; Barbera, Marco; Gelardi, Franco M.; Sciortino, Luisa; Collura, Alfonso; Lo Cicero, Ugo; Cannas, Marco

    2015-09-01

    This work shows the development of an innovative solar CHP system for the combined production of heat and power based upon HCPV modules working at the high concentration level of 2000 suns. The solar radiation is concentrated on commercial InGaP/InGaAs/Ge triple-junction solar cells designed for intensive work. The primary optics is a rectangular off-axis parabolic mirror while a secondary optic at the focus of the parabolic mirror is glued in optical contact with the cell. Each module consist of 2 axis tracker (Alt-Alt type) with 20 multijunction cells each one integrated with an active heat sink. The cell is connected to an active heat transfer system that allows to keep the cell at a high level of electrical efficiency (ηel > 30 %), bringing the heat transfer fluid (water and glycol) up to an output temperature of 90°C. Accordingly with the experimental data collected from the first 1 kWe prototype, the total amount of extracted thermal energy is above the 50% of the harvested solar radiation. That, in addition the electrical efficiency of the system contributes to reach an overall CHP efficiency of more than the 80%.

  19. Performance Characteristics of Hybrid Cycle Combined Absorption Heat Transformer and Absorption Refrigerating Machine

    Science.gov (United States)

    Iyoki, Shigeki; Otsuka, Shin-Ichi; Uemura, Tadashi

    In this paper, four kinds of hybrid cycles which combined the single-stage absorption refrigerating machine and four kinds of absorption heat transformers were proposed. It is possible that each of these hybrid cycles gets high temperature and low temperature from one cycle, simultaneously. As basic cycle of absorption heat transformer, the following were chosen: two kinds of single-stage absorption heat transformer and two kinds of two-stage absorption heat transformer. As a working medium-absorbent system, H2O-LiBr system, H2O-LiBr-LiNO3 system, H2O-LiBr-LiNO3-LiCl system, H2O-LiBr-C2H6O2 system and H2O-LiNO3-LiCl system were adopted. Using these five kinds of working medium-absorbent system, the performance characteristics of four kinds of hybrid cycle were simulated. And the performance characteristics of these cycles were compared.

  20. Combined heat and power generation with a HCPV system at 2000 suns

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Filippo; Montagnino, Fabio M.; Milone, Sergio [IDEA s.r.l., C.da Molara Z.I. III Fase, 90018 Termini Imerese (Italy); Salinari, Piero; Agnello, Simonpietro; Gelardi, Franco M.; Sciortino, Luisa; Cannas, Marco [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, 90123 Palermo (Italy); Bonsignore, Gaetano; Barbera, Marco [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, 90123 Palermo (Italy); INAF, Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo (Italy); Collura, Alfonso; Lo Cicero, Ugo [INAF, Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo (Italy)

    2015-09-28

    This work shows the development of an innovative solar CHP system for the combined production of heat and power based upon HCPV modules working at the high concentration level of 2000 suns. The solar radiation is concentrated on commercial InGaP/InGaAs/Ge triple-junction solar cells designed for intensive work. The primary optics is a rectangular off-axis parabolic mirror while a secondary optic at the focus of the parabolic mirror is glued in optical contact with the cell. Each module consist of 2 axis tracker (Alt-Alt type) with 20 multijunction cells each one integrated with an active heat sink. The cell is connected to an active heat transfer system that allows to keep the cell at a high level of electrical efficiency (ηel > 30 %), bringing the heat transfer fluid (water and glycol) up to an output temperature of 90°C. Accordingly with the experimental data collected from the first 1 kWe prototype, the total amount of extracted thermal energy is above the 50% of the harvested solar radiation. That, in addition the electrical efficiency of the system contributes to reach an overall CHP efficiency of more than the 80%.

  1. Combined mass and heat exchange network synthesis based on stage-wise superstructure model☆

    Institute of Scientific and Technical Information of China (English)

    Linlin Liu; Jian Du; Fenglin Yang

    2015-01-01

    Integrating multiple systems into one has become an important trend in Process Systems Engineering research field since there is strong demand from the modern industries. In this study, a stage-wise superstructure-based method is proposed to synthesize a combined mass and heat exchange network (CM&HEN) which has two parts as the mass exchange network (MEN) and heat exchange network (HEN) involved. To express the pos-sible heat exchange requirements resulted from mass exchange operations, a so cal ed“indistinct HEN super-structure (IHS)”, which can contain the all potential matches between streams, is constructed at first. Then, a non-linear programming (NLP) mathematical model is established for the simultaneous synthesis and optimiza-tion of networks. Therein, the interaction between mass exchange and heat exchange is modeling formulated. The NLP model has later been examined using an example from literature, and the effectiveness of the proposed method has been demonstrated with the results.

  2. Heat pump system for summer houses if possible combined with solar heating; Varmepumpeanlaeg til fritidshus eventuelt i kombination med solvarme

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K.; Kildemoes, T.; Kristensen, Joern; Bjergen Jensen, T.

    2006-03-15

    Denmark has about 220.000 summer cottages and it is estimated that about 10% of these are for rental. The trend within summer cottages for rental is going towards more and more facilities and intensive rental, and as a consequence of this high energy consumption. A substantial part of the energy use is for heating, i.e. space heating, heating of indoor pool and domestic hot water. Contrary to the other building stock in Denmark summer cottages nearly always use electricity for heating. In the project it is found, that the average yearly electricity use of a summer cottage for rental with indoor pool is about 31.000 kWh. In the project typical energy consumption profiles have been set up from analyses of typical equipment and from simulation of space heat demands in Danish climate. Furthermore a number of heat delivery solutions with heat pumps and solar heating systems have been set up and the performance has been simulated and analysed. As a result of the analyses 2 prototype systems both consisting of an air to air heat pump for space heating and an air to water heat pump for the hot water, the spa and the pool heating has been installed and tested in two summer cottages. There is a good economy in the systems and these are therefore marketed by the project participants, Energi Danmark NRGi (energy utility) and Dansommer (cottage rental company). (au)

  3. Development of a river ice jam by a combined heat loss and hydraulic model

    Science.gov (United States)

    Eliasson, J.; Gröndal, G. O.

    2008-11-01

    The heat loss theory and the hydraulic theory for the analysis of the development of wide channel ice jams are discussed and shown. The heat loss theory has been used in Iceland for a long time, while the hydraulic theory largely follows the classical ice-jam build-up theories used in known CFD models. The results are combined in a new method to calculate the maximum thickness and the extent of an ice jam. The results compare favorably to the HEC-RAS model for the development of a very large ice jam in Thjorsa River in Iceland, and have been found in good agreement with historical data, collected where a hydroelectric dam project, Urridafoss, is being planned in the Thjorsa River.

  4. Thermoeconomic Optimization of a Combined Heating and Humidification Coil for HVAC Systems

    Science.gov (United States)

    Teodoros, Liliana; Andresen, Bjarne

    2016-07-01

    The total cost of ownership is calculated for a combined heating and humidification coil of an air-handling unit taking into account investment and operation costs simultaneously. This total cost represents the optimization function for which the minimum is sought. The parameters for the cost dependencies are the physical dimensions of the coil: length, width and height. The term "coil" is used generically since in this setup it generates heating as well as humidification in a single unit. The first part of the paper deals with the constructive optimization and finds the relationship between the dimensions for a minimum cost. The second part of the paper takes the results of the constructive optimization further and, based on the data derived in our previous papers, analyzes the minimum total cost for the humidification coil while balancing the amount of water used to humidify the air and modify its temperature.

  5. Development of a river ice jam by a combined heat loss and hydraulic model

    Directory of Open Access Journals (Sweden)

    J. Eliasson

    2008-11-01

    Full Text Available The heat loss theory and the hydraulic theory for the analysis of the development of wide channel ice jams are discussed and shown. The heat loss theory has been used in Iceland for a long time, while the hydraulic theory largely follows the classical ice-jam build-up theories used in known CFD models. The results are combined in a new method to calculate the maximum thickness and the extent of an ice jam. The results compare favorably to the HEC-RAS model for the development of a very large ice jam in Thjorsa River in Iceland, and have been found in good agreement with historical data, collected where a hydroelectric dam project, Urridafoss, is being planned in the Thjorsa River.

  6. Optimization of micro combined heat and power gas turbine by genetic algorithm

    Directory of Open Access Journals (Sweden)

    Yazdi Behnam Ahrar

    2015-01-01

    Full Text Available In this paper, a comprehensive thermodynamic modeling and multi-objective optimization of a micro turbine cycle in combined heat and power generation, which provides 100KW of electric power. This CHP System is composed of air compressor, combustion chamber (CC, Air Preheater, Gas Turbine (GT and a Heat Recovery Heat Exchanger. In this paper, at the first stage, the each part of the micro turbine cycle is modeled using thermodynamic laws. Next, with using the energetic and exergetic concepts and applying economic and environmental functions, the multi-objectives optimization of micro turbine in combined heat and power generation is performed. The design parameters of this cycle are compressor pressure ratio (rAC, compressor isentropic efficiency (ηAC, GT isentropic efficiency (ηGT, CC inlet temperature (T3, and turbine inlet temperature (T4. In the multi-objective optimization three objective functions, including CHP exergy efficiency, total cost rate of the system products, and CO2 emission of the whole plant, are considered. Theexergoenvironmental objective function is minimized whereas power plant exergy efficiency is maximized usinga Genetic algorithm. To have a good insight into this study, a sensitivity analysis of the result to the fuel cost is performed. The results show that at the lower exergetic efficiency, in which the weight of exergo-environmental objective is higher, the sensitivity of the optimal solutions to the fuel cost is much higher than the location of the Pareto Frontier with the lower weight of exergo-environmental objective. In addition, with increasing exergy efficiency, the purchase cost of equipment in the plant is increased as the cost rate of the plant increases.

  7. Long-term optimization case studies for combined heat and power system

    Directory of Open Access Journals (Sweden)

    Polyzakis Apostolis L.

    2009-01-01

    Full Text Available In the next years distributed poly-generation systems are expected to play an increasingly important role in the electricity infrastructure and market. The successful spread of small-scale generation either connected to the distribution network or on the customer side of the meter depends on diverse issues, such as the possibilities of technical implementation, resource availability, environmental aspects, and regulation and market conditions. The aim of this approach is to develop an economic and parametric analysis of a distributed generation system based on gas turbines able to satisfy the energy demand of a typical hotel complex. Here, the economic performance of six cases combining different designs and regimes of operation is shown. The software Turbomatch, the gas turbine performance code of Cranfield University, was used to simulate the off-design performance of the engines in different ambient and load conditions. A clear distinction between cases running at full load and following the load could be observed in the results. Full load regime can give a shorter return on the investment then following the load. In spite combined heat and power systems being currently not economically attractive, this scenario may change in future due to environmental regulations and unavailability of low price fuel for large centralized power stations. Combined heat and power has a significant potential although it requires favorable legislative and fair energy market conditions to successfully increase its share in the power generation market.

  8. Cycle Analysis using Exhaust Heat of SOFC and Turbine Combined Cycle by Absorption Chiller

    Science.gov (United States)

    Takezawa, Shinya; Wakahara, Kenji; Araki, Takuto; Onda, Kazuo; Nagata, Susumu

    A power generating efficiency of solid oxide fuel cell (SOFC) and gas turbine combined cycle is fairly high. However, the exhaust gas temperature of the combined cycle is still high, about 300°C. So it should be recovered for energy saving, for example, by absorption chiller. The energy demand for refrigeration cooling is recently increasing year by year in Japan. Then, we propose here a cogeneration system by series connection of SOFC, gas turbine and LiBr absorption chiller to convert the exhaust heat to the cooling heat. As a result of cycle analysis of the combined system with 500kW class SOFC, the bottoming single-effect absorption chiller can produce the refrigerating capacity of about 120kW, and the double-effect absorption chiller can produce a little higher refrigerating capacity of about 130kW without any additional fuel. But the double-effect absorption chiller became more expensive and complex than the single-effect chiller.

  9. New gasification plants for combined heat and power in Denmark; Nye forgasningsanlaeg til kraftvarme i Danmark

    Energy Technology Data Exchange (ETDEWEB)

    Houmoeller, S.

    1997-12-31

    In Danish energy planning, the role of combined heat and power generation has been increasing. This has aroused an interest in gasification of biofuels. Several gasification techniques are being developed and the focus is on wood rather than straw. This conference paper describes the present projects in this field and lists the advantages and disadvantages of each technique. The tar content of the gas is a problem. A recent attempt has been made to decompose the tar in biogas plants. Gasification plants are supposed to be commercially available within a few years

  10. Combined Heat and Power: A Decade of Progress, A Vision for the Future

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-08-01

    Over the past 10 years, DOE has built a solid foundation for a robust CHP marketplace. We have aligned with key partners to produce innovative technologies and spearhead market-transforming projects. Our commercialization activities and Clean Energy Regional Application Centers have expanded CHP across the nation. More must be done to tap CHP’s full potential. Read more about DOE’s CHP Program in “Combined Heat and Power: A Decade of Progress, A Vision for the Future.”

  11. Non-gray combined conduction and radiation heat transfer by using FVM and SLW

    Science.gov (United States)

    Sun, Yujia; Zhang, Xiaobing; Howell, John R.

    2017-08-01

    To investigate non-gray combined conduction and radiation problems, this paper uses the FVM to solve the energy equation and radiative transfer equation and the SLW method to model the effect of gas spectral properties in a 2D geometry. Carbon dioxide, water vapor and carbon monoxide are considered as the participating media. The effects of gas species, gas mixture ratios and wall emissivities on the temperature and heat flux were investigated. The accuracy of the gray gas model is also analyzed compared to the SLW method.

  12. New integrated gas turbine CHP (combined heat and power) and incinerator plant.

    Science.gov (United States)

    Briggs, R A; Yates, B

    1990-12-01

    Despite the complex nature of the project, the clients brief of a 14 month design and installation period was achieved within the approved budget of 2.5 million pounds. Early performance figures indicate that the scheme is on target to achieve the original payback of under four years. Queen Elizabeth Hospital: installation of integrated combined heat and power plant. Client: Central Birmingham Health Authority. Consulting Engineers/Project Managers: Yates, Edge and Partners. Architects: Temple Cox and Nichols. Structural Engineers: Peel and Fowler. Quantity Surveyor: West Midlands Regional Health Authority.

  13. 3 MW solid rotating target design

    Science.gov (United States)

    McManamy, T.; Rennich, M.; Gallmeier, F.; Ferguson, P.; Janney, J.

    2010-03-01

    A rotating solid target design concept is being developed for potential use at the second SNS target station (STS). A long pulse beam (˜1 ms) at 1.3 GeV and 20 Hz is planned with power levels at or above 1 MW. Since the long pulse may give future opportunities for higher power, this study is looking at 3 MW to compare the performance of a solid rotating target to a mercury target. Unlike the case for stationary solid targets at such powers this study indicates that a rotating solid target, when used with large coupled hydrogen moderators, has neutronic performance equal to or better than that with a mercury target, and the solid target has a greatly increased lifetime. Design studies have investigated water cooled tungsten targets with tantalum cladding approximately 1.2 m in diameter, and 70 mm thick. Operating temperatures are low (plane, top and bottom surface cooling. In case of cooling system failure, the diameter gives enough surface area to remove the decay heat by radiation to the surrounding reflector assemblies while keeping the peak temperatures below approximately 700 °C. This temperature should mitigate potential loss of coolant accidents and subsequent steam, tungsten interaction which has a threshold of approximately 800 °C. Design layouts for the sealing systems and potential target station concepts have been developed.

  14. A Total Cost of Ownership Model for Low Temperature PEM Fuel Cells in Combined Heat and Power and Backup Power Applications

    Energy Technology Data Exchange (ETDEWEB)

    University of California, Berkeley; Wei, Max; Lipman, Timothy; Mayyas, Ahmad; Chien, Joshua; Chan, Shuk Han; Gosselin, David; Breunig, Hanna; Stadler, Michael; McKone, Thomas; Beattie, Paul; Chong, Patricia; Colella, Whitney; James, Brian

    2014-06-23

    A total cost of ownership model is described for low temperature proton exchange membrane stationary fuel cell systems for combined heat and power (CHP) applications from 1-250kW and backup power applications from 1-50kW. System designs and functional specifications for these two applications were developed across the range of system power levels. Bottom-up cost estimates were made for balance of plant costs, and detailed direct cost estimates for key fuel cell stack components were derived using design-for-manufacturing-and-assembly techniques. The development of high throughput, automated processes achieving high yield are projected to reduce the cost for fuel cell stacks to the $300/kW level at an annual production volume of 100 MW. Several promising combinations of building types and geographical location in the U.S. were identified for installation of fuel cell CHP systems based on the LBNL modelling tool DER CAM. Life-cycle modelling and externality assessment were done for hotels and hospitals. Reduced electricity demand charges, heating credits and carbon credits can reduce the effective cost of electricity ($/kWhe) by 26-44percent in locations such as Minneapolis, where high carbon intensity electricity from the grid is displaces by a fuel cell system operating on reformate fuel. This project extends the scope of existing cost studies to include externalities and ancillary financial benefits and thus provides a more comprehensive picture of fuel cell system benefits, consistent with a policy and incentive environment that increasingly values these ancillary benefits. The project provides a critical, new modelling capacity and should aid a broad range of policy makers in assessing the integrated costs and benefits of fuel cell systems versus other distributed generation technologies.

  15. Characterization of biomass producer gas as fuel for stationary gas engines in combined heat and power production

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper

    2008-01-01

    The aim of this project has been the characterization of biomass producer gas as a fuel for stationary gas engines in heat and power production. More than 3200 hours of gas engine operation, with producer gas as fuel, has been conducted at the biomass gasification combined heat and power (CHP...

  16. Ultra Clean 1.1MW High Efficiency Natural Gas Engine Powered System

    Energy Technology Data Exchange (ETDEWEB)

    Zurlo, James; Lueck, Steve

    2011-08-31

    Dresser, Inc. (GE Energy, Waukesha gas engines) will develop, test, demonstrate, and commercialize a 1.1 Megawatt (MW) natural gas fueled combined heat and power reciprocating engine powered package. This package will feature a total efficiency > 75% and ultra low CARB permitting emissions. Our modular design will cover the 1 – 6 MW size range, and this scalable technology can be used in both smaller and larger engine powered CHP packages. To further advance one of the key advantages of reciprocating engines, the engine, generator and CHP package will be optimized for low initial and operating costs. Dresser, Inc. will leverage the knowledge gained in the DOE - ARES program. Dresser, Inc. will work with commercial, regulatory, and government entities to help break down barriers to wider deployment of CHP. The outcome of this project will be a commercially successful 1.1 MW CHP package with high electrical and total efficiency that will significantly reduce emissions compared to the current central power plant paradigm. Principal objectives by phases for Budget Period 1 include: • Phase 1 – market study to determine optimum system performance, target first cost, lifecycle cost, and creation of a detailed product specification. • Phase 2 – Refinement of the Waukesha CHP system design concepts, identification of critical characteristics, initial evaluation of technical solutions, and risk mitigation plans. Background

  17. Advances and historical developments of MW hyperthermia and the relevance to thermal ablation

    Science.gov (United States)

    Turner, Paul F.; Youd, Thomas; Turner, P. Scott

    2007-02-01

    Early work utilizing MW energy for thermal treatment or ablation of tissues such as liver using coherent phased arrays began in 1979. This early work involved the use of multiple interstitial antennas driven with the same phase and equal power at 915 MHz through the use of a power splitter. Early models of the antenna utilized a hypodermic needle that was transformed into an antenna by the deployment of an insulated coaxial central wire beyond the end of the needle. Early unpublished treatments of tissue phantoms and swine liver demonstrated the feasibility of such a design for selective tissue damage, but sufficient image and targeting methods had not been sufficiently developed to support such applications. MW therapeutic technology was subsequently commercialized in combination with invasive radiation therapy called brachytherapy. For this application coherent arrays of coaxial antennas were inserted into cancerous tumors. Initial investigators would deploy these into the tumor through 14 gauge plastic angiocatheters. In later procedures, the antennas were inserted into the same closed-end plastic catheters used for insertion of the radiation sources. MW energy delivery through the walls of closed-end plastic catheters and numerical pretreatment planning has been in clinical practice since 1984. Recent development of numerical models, split tissue equivalent phantoms with IR imaging, and tissue ablation studies have led to new insights in microwave ablation applications. Current research will improve ablative heat therapy with increased temperatures and power to improve stand alone thermal treatments.

  18. Thermodynamic and economic analysis of integrating lignocellulosic bioethanol production in a Danish combined heat and power unit

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

    Integrating lignocellulosic bioethanol production with combined heat and power (CHP) production in polygeneration systems is considered an efficient and competitive way to produce a sustainable fuel for the transportation sector. This study assessed the energy economy of integrating lignocellulosic...

  19. Opportunities for Combined Heat and Power at Wastewater Treatment Facilities: Market Analysis and Lessons from the Field

    Science.gov (United States)

    This report presents the opportunities for combined heat and power (CHP) applications in the municipal wastewater treatment sector, and it documents the experiences of the wastewater treatment facility (WWTF) operators who have employed CHP.

  20. ASSESSMENT OF COMBINED HEAT AND POWER SYSTEM"PREMIUM POWER" APPLICATIONS IN CALIFORNIA

    Energy Technology Data Exchange (ETDEWEB)

    Norwood, Zack; Lipman, Timothy; Stadler, Michael; Marnay, Chris

    2010-06-01

    The effectiveness of combined heat and power (CHP) systems for power interruption intolerant,"premium power," facilities is the focus of this study. Through three real-world case studies and economic cost minimization modeling, the economic and environmental performance of"premium power" CHP is analyzed. The results of the analysis for a brewery, data center, and hospital lead to some interesting conclusions about CHP limited to the specific CHP technologies installed at those sites. Firstly, facilities with high heating loads prove to be the most appropriate for CHP installations from a purely economic standpoint. Secondly, waste heat driven thermal cooling systems are only economically attractive if the technology for these chillers can increase above the current best system efficiency. Thirdly, if the reliability of CHP systems proves to be as high as diesel generators they could replace these generators at little or no additional cost if the thermal to electric (relative) load of those facilities was already high enough to economically justify a CHP system. Lastly, in terms of greenhouse gas emissions, the modeled CHP systems provide some degree of decreased emissions, estimated at approximately 10percent for the hospital, the application with the highest relative thermal load in this case

  1. On policy instruments for support of micro combined heat and power

    Energy Technology Data Exchange (ETDEWEB)

    Hawkes, A.D. [Centre for Energy Policy and Technology, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Leach, M.A. [Centre for Environmental Strategy, Faculty of Engineering, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2008-08-15

    The performance of residential micro combined heat and power (micro-CHP) - a technology to provide heat and some electricity to individual dwellings - is generally dependent on the magnitude of household thermal energy demand. Dwellings with larger and more consistent thermal consumption perform well economically and achieve greater greenhouse gas emissions savings. Consequently, the performance of micro-CHP is dependent on the level of thermal insulation in a dwelling. Therefore, emerging policy approaches regarding energy use in the residential sector, which generally support both energy efficiency measures such as thermal insulation and adoption of micro-CHP, may inadvertently incentivise micro-CHP installation where CO{sub 2} reductions are meagre or not cost-effective. This article examines this issue in terms of the changes in economic and environmental performance that occur for three micro-CHP technologies under changing patterns of residential thermal insulation in the United Kingdom. The results of this analysis are used to comment on the structure of policy instruments that support micro-CHP. It is found that simultaneous support for energy efficiency measures and micro-CHP can be justified, but care must be taken to ensure that the heat-to-power ratio and capacity of the micro-CHP system are appropriate for the expected thermal demand of the target dwelling. (author)

  2. DENSIFICATION OF WOOD VENEERS COMBINED WITH OIL-HEAT TREATMENT. PART II: HYGROSCOPICITY AND MECHANICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Chang-Hua Fang,

    2012-01-01

    Full Text Available In an effort to achieve high mechanical performance and improved dimensional stability, densification combined with oil-heat treatment (OHT was performed. In our previous study, OHT was successfully applied to densified veneer, which resulted in improved dimensional stability. In the present study, the impact of OHT on densified wood veneer hygroscopicity and mechanical properties was determined. OHT at 180, 200, and 220ºC for 1, 2, and 3 hours was applied to densified Aspen (Populus tremuloides veneers. OHT was found to be an efficient treatment to reduce the hygroscopicity of densified aspen veneers, although OHT had a negative impact on Brinell hardness. However, due to the contribution of densification, the hardness of oil-heat treated veneers was still two to three times higher than that of non-densified veneers. Similar results were found for tensile strength. Bending strength increased slightly at low OHT temperature, and then decreased at high temperature. Bending strength of oil-heat treated densified veneer samples was higher than that of non-densified ones. No significant effect of OHT was found on tensile MOE, but bending MOE increased after OHT. Compared to OHT duration, OHT temperature had a larger impact on densified wood hygroscopicity and mechanical properties.

  3. Boechera species exhibit species-specific responses to combined heat and high light stress.

    Science.gov (United States)

    Gallas, Genna; Waters, Elizabeth R

    2015-01-01

    As sessile organisms, plants must be able to complete their life cycle in place and therefore tolerance to abiotic stress has had a major role in shaping biogeographical patterns. However, much of what we know about plant tolerance to abiotic stresses is based on studies of just a few plant species, most notably the model species Arabidopsis thaliana. In this study we examine natural variation in the stress responses of five diverse Boechera (Brassicaceae) species. Boechera plants were exposed to basal and acquired combined heat and high light stress. Plant response to these stresses was evaluated based on chlorophyll fluorescence measurements, induction of leaf chlorosis, and gene expression. Many of the Boechera species were more tolerant to heat and high light stress than A. thaliana. Gene expression data indicates that two important marker genes for stress responses: APX2 (Ascorbate peroxidase 2) and HsfA2 (Heat shock transcription factor A2) have distinct species-specific expression patterns. The findings of species-specific responses and tolerance to stress indicate that stress pathways are evolutionarily labile even among closely related species.

  4. Performance study of a Stirling engine in a combined heat and power system

    Energy Technology Data Exchange (ETDEWEB)

    Aliabadi, A.; Thomson, M.; Wallace, J.; Tzanetakis, T. [Toronto Univ., ON (Canada). Dept. of Mechanical and Industrial Engineering

    2007-07-01

    The use of biofuels in engines can result in poor ignition quality, long ignition delays, and long residence times. However, biofuels can be used efficiently in low power applications with Stirling engines. This study examined biofuels combustion in a retrofitted commercially-available combined heat and power (CHP) system. The system consisted of a burner, a Stirling engine, a generator and a controller. The Stirling cycle consisted of 4 processes: an isothermal expansion; a constant volume regeneration; an isothermal compression; and a constant volume regeneration. Tests were conducted to run the CHP unit in a heat-manage mode with coolant and combustion temperature set points of 70 and 460 degrees C for a period of 1 hour and 45 minutes. Air and fuel supply rates were regulated in order to control heat input into the system. A steady state energy balance analysis was then performed. Results of the experimental study showed that the system was capable of producing 0.8 kW of electrical and 5.5 kW of thermal power. An energy balance analysis was used to create an experimental benchmark performance of the unit. A revised fueling system is also being designed to combust the biomass pyrolysis oil. 7 refs., 2 tabs., 10 figs.

  5. Study on the application of combined cooling, heating and power system with biomass energy in China

    Science.gov (United States)

    Guan, Haibin; Sun, Rongfeng; Zhang, Weijie; Fan, Xiaoxu; Jiang, Jianguo; Zhao, Baofeng

    2017-08-01

    CCHP (Combined Cooling Heating and Power) system is highly evaluated and developed rapidly around the world possessing better performance than traditional energy systems because of the cascade utilization of energy. Biomass is one of the renewable energy resources that is abundant and has been widely used in China for a long time. In this paper the principle and development of biomass gasification system and CCHP is clarified, the feasibility of combining the two systems together is analyzed from theoretical and technical points of view, and the active significance is also indicated. In conclusion, it is feasible to develop CCHP with Biomass Energy in an agricultural country such as China, which can flourish in the future.

  6. Application of artificial neural networks to the condition monitoring and diagnosis of a combined heat and power plant

    Energy Technology Data Exchange (ETDEWEB)

    Fast, M. [Division of Thermal Power Engineering, Department of Energy Sciences, Lund University, P.O. Box 118, S-221 00 Lund (Sweden); Palme, T. [Department of Mechanical and Structural Engineering and Materials Science, University of Stavanger, N-4036 Stavanger (Norway)

    2010-02-15

    The objective of this study has been to create an online system for condition monitoring and diagnosis of a combined heat and power plant in Sweden. The system in question consisted of artificial neural network models, representing each main component of the combined heat and power plant, connected to a graphical user interface. The artificial neural network models were integrated on a power generation information manager server in the computer system of the combined heat and power plant, and the graphical user interface was made available on workstations connected to this server. The plant comprised a Siemens SGT800 gas turbine with a heat recovery steam generator as well as a bio-fueled boiler and its steam cycle. Steam from the heat recovery steam generator and the bio-fueled boiler expanded together in a common steam turbine, producing both electricity and heat. The artificial neural network models were trained with operational data from the components of the combined heat and power plant. Accurate predictions from the ANN (Artificial neural network) models in combination with an undemanding integration in the power plant's computer system were some of the main conclusions from this study. (author)

  7. Drought stress had a predominant effect over heat stress on three tomato cultivars subjected to combined stress.

    Science.gov (United States)

    Zhou, Rong; Yu, Xiaqing; Ottosen, Carl-Otto; Rosenqvist, Eva; Zhao, Liping; Wang, Yinlei; Yu, Wengui; Zhao, Tongmin; Wu, Zhen

    2017-01-25

    Abiotic stresses due to environmental factors could adversely affect the growth and development of crops. Among the abiotic stresses, drought and heat stress are two critical threats to crop growth and sustainable agriculture worldwide. Considering global climate change, incidence of combined drought and heat stress is likely to increase. The aim of this study was to shed light on plant growth performance and leaf physiology of three tomatoes cultivars ('Arvento', 'LA1994' and 'LA2093') under control, drought, heat and combined stress. Shoot fresh and dry weight, leaf area and relative water content of all cultivars significantly decreased under drought and combined stress as compared to control. The net photosynthesis and starch content were significantly lower under drought and combined stress than control in the three cultivars. Stomata and pore length of the three cultivars significantly decreased under drought and combined stress as compared to control. The tomato 'Arvento' was more affected by heat stress than 'LA1994' and 'LA2093' due to significant decreases in shoot dry weight, chlorophyll a and carotenoid content, starch content and NPQ (non-photochemical quenching) only in 'Arvento' under heat treatment. By comparison, the two heat-tolerant tomatoes were more affected by drought stress compared to 'Arvento' as shown by small stomatal and pore area, decreased sucrose content, ΦPSII (quantum yield of photosystem II), ETR (electron transport rate) and qL (fraction of open PSII centers) in 'LA1994' and 'LA2093'. The three cultivars showed similar response when subjected to the combination of drought and heat stress as shown by most physiological parameters, even though only 'LA1994' and 'LA2093' showed decreased Fv/Fm (maximum potential quantum efficiency of photosystem II), ΦPSII, ETR and qL under combined stress. The cultivars differing in heat sensitivity did not show difference in the combined stress sensitivity, indicating that selection for tomatoes

  8. Elastic characterization of platinum/rhodium alloy at high temperature by combined laser heating and laser ultrasonic techniques.

    Science.gov (United States)

    Burgess, K; Prakapenka, V; Hellebrand, E; Zinin, P V

    2014-04-01

    We demonstrate an innovative pump-probe technique combined with laser heating to determine the velocity of a surface Rayleigh wave at high temperature. Laser ultrasonics in a point-source-point-receiver configuration was combined with laser heating to evaluate the elastic properties of micron size specimens. The measurements of the velocity of the surface Rayleigh wave (SRW) were conducted at 1070K. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. 20-MW Magnicon for ILC

    Energy Technology Data Exchange (ETDEWEB)

    Jay L. Hirshfield

    2006-11-29

    The 1.3 GHz RF power to drive ILC is now planned to be supplied by 600-1200, 10-MW peak power multi-beam klystrons. In this project, a conceptual design for 1.3 GHz magnicons with 20 MW peak power was developed as an alternative to the klystrons, with the possibility of cutting in half the numbers of high-power tubes and associated components. Design of a conventional magnicon is described, using TM110 modes in all cavities, as well as design of a modified magnicon with a TE111 mode output cavity. The latter has the advantage of much lower surface fields than the TM110 mode, with no loss of output power or electronic efficiency.

  10. Mapping of combined heat and power systems in cane sugar industry

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, M.S.; Rajkumar, N. [Central Power Research Institute, Sreekariyam (India). Energy Research Centre

    2001-12-01

    Cogenerating systems based on steam turbines (1-20 MWt) are indispensable when the source of energy is a solid fuel such as bagasse as in a sugar industry. These systems provide a wide range of heat to power ratios from 0 to as high as 100. The energy productivity of sugar plants differ vastly because of variations in equipment efficiency, system configuration and operating steam conditions. In this paper a mapping of the entire operating range of steam based combined heat and power plants spanning pure back pressure to pure condensing environments, based on standard steam conditions in installations and efficiencies which are currently being achieved experimentally, is presented. This will enable the rational choice of combinations, which will yield the best economic advantage. As the operating steam pressure is increased (and consequently the matching superheated temperatures) the in-house steam requirement reduces drastically and simultaneously the exportable power increases. Improvements in the systems by the use of advanced designs of steam turbines and introduction of information technologies and associated supervision control and data acquisition, energy management system, multi-media interaction, etc., is also briefly highlighted. The maximum exportable electrical power from a sugar mill after meeting the internal requirement is around 146 kW h/t of cane. The maximum exportable of steam (no power export) is around 0.65 t/t of cane. (author)

  11. Performance of a convective, infrared and combined infrared- convective heated conveyor-belt dryer.

    Science.gov (United States)

    El-Mesery, Hany S; Mwithiga, Gikuru

    2015-05-01

    A conveyor-belt dryer was developed using a combined infrared and hot air heating system that can be used in the drying of fruits and vegetables. The drying system having two chambers was fitted with infrared radiation heaters and through-flow hot air was provided from a convective heating system. The system was designed to operate under either infrared radiation and cold air (IR-CA) settings of 2000 W/m(2) with forced ambient air at 30 °C and air flow of 0.6 m/s or combined infrared and hot air convection (IR-HA) dryer setting with infrared intensity set at 2000 W/m(2) and hot at 60 °C being blown through the dryer at a velocity of 0.6 m/s or hot air convection (HA) at an air temperature of 60 °C and air flow velocity 0.6 m/s but without infrared heating. Apple slices dried under the different dryer settings were evaluated for quality and energy requirements. It was found that drying of apple (Golden Delicious) slices took place in the falling rate drying period and no constant rate period of drying was observed under any of the test conditions. The IR-HA setting was 57.5 and 39.1 % faster than IR-CA and HA setting, respectively. Specific energy consumption was lower and thermal efficiency was higher for the IR-HA setting when compared to both IR-CA and HA settings. The rehydration ratio, shrinkage and colour properties of apples dried under IR-HA conditions were better than for either IR-CA or HA.

  12. Analysis of temperature of underground heat exchanger and efficiency of heat pump with combined cooling and heating%联供模式地下换热器温变及其热泵效能分析

    Institute of Scientific and Technical Information of China (English)

    齐子姝; 高青; 刘研; 于鸣

    2012-01-01

    A thermodynamic calculation model was built for the ground source heat pump based on the G-function theory of the underground heat exchanger. The basic performance of the underground heat exchanger and the heat pump, and the main differences between the combined cooling and heating mode and the single mode were studied. The thermodynamic parameters, such as the coefficient of performance of the heat pump, and the energy consumption were analyzed comparatively by calculating the borehole wall temperatures and the fluid temperatures at the inlet and outlet of the underground heat exchanger. Taking the severe cold region and the hot summer and cold winter region as examples, the effects of the combined cooling and heating, and the single cooling or heating on the temperatures of the underground heat exchanger and the efficiency of the heat pump were studied in combination with the cooling and heating load demands.%在地下换热器G函数理论基础上,建立了地源热泵热力过程计算模型。研究了地下换热器和热泵运行的基本性能,及其单供和联供的主要差异。通过计算孔井壁面温度及地下换热器进、出口流体温度,对热泵能效比、能耗等热力参数进行了对比分析。以严寒地区和夏热冬冷地区为例,结合冷热负荷需求,研究了冷热单供与联供方式对地下换热器温变和热泵效能的影响作用。

  13. Residential Solar Combined Heat and Power Generation using Solar Thermoelectric Generation

    Science.gov (United States)

    Ohara, B.; Wagner, M.; Kunkle, C.; Watson, P.; Williams, R.; Donohoe, R.; Ugarte, K.; Wilmoth, R.; Chong, M. Zachary; Lee, H.

    2015-06-01

    Recent reports on improved efficiencies of solar thermoelectric generation (STEG) systems have generated interest in STEGs as a competitive power generation system. In this paper, the design of a combined cooling and power utilizing concentrated solar power is discussed. Solar radiation is concentrated into a receiver connected to thermoelectric modules, which are used as a topping cycle to generate power and high grade heat necessary to run an absorption chiller. Modeling of the overall system is discussed with experimental data to validate modeling results. A numerical modeling approach is presented which considers temperature variation of the source and sink temperatures and is used to maximize combined efficiency. A system is built with a demonstrated combined efficiency of 32% in actual working conditions with power generation of 3.1 W. Modeling results fell within 3% of the experimental results verifying the approach. An optimization study is performed on the mirror concentration ration and number of modules for thermal load matching and is shown to improve power generation to 26.8 W.

  14. Modelling a Combined Heat and Power Plant based on Gasification, Micro Gas Turbine and Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud

    2009-01-01

    A system level modelling study on two combined heat and power (CHP) systems both based on biomass gasification. One system converts the product gas in a micro gas turbine (MGT) and the other in a combined solid oxide fuel cell (SOFC) and MGT arrangement. An electrochemical model of the SOFC has...

  15. Modelling a Combined Heat and Power Plant based on Gasification, Micro Gas Turbine and Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud

    2009-01-01

    A system level modelling study on two combined heat and power (CHP) systems both based on biomass gasification. One system converts the product gas in a micro gas turbine (MGT) and the other in a combined solid oxide fuel cell (SOFC) and MGT arrangement. An electrochemical model of the SOFC has...

  16. The surface heat flow of the Arabian Shield in Jordan

    Science.gov (United States)

    Förster, A.; Förster, H.-J.; Masarweh, R.; Masri, A.; Tarawneh, K.; Desert Group

    2007-04-01

    Surface heat flow in southern Jordan (western part of the Arabian Plate) was determined in a dense cluster of five, up to 900-m-deep boreholes that have encountered sedimentary rocks of Paleozoic (Ordovician and Silurian) age. These rocks are underlain by an igneous and metamorphic basement, which has been studied for its radiogenic heat production, along the eastern margin of the Dead Sea Transform (DST) fault system. The heat flow, calculated from continuous temperature logs and laboratory-measured thermal conductivity of drillcores and surface samples, averages to 60.3 ± 3.4 mW m -2 and contrasts the common view of the late Proterozoic-consolidated Arabian Shield constituting a low heat-flow province of ⩽45 mW m -2. Although only characterizing an area of about 300 km 2, this average is unlikely representing a positive local anomaly caused by voluminous HHP granites/rhyolites at shallow depths. Instead, a heat flow of 60 mW m -2 is considered a robust estimate of the Phanerozoic conductive surface heat flow not only for Jordan, but for the Arabian Shield in areas unaffected by younger reactivation. The large variation in conductive heat flow (36-88 mW m -2) previously observed in Jordan, southern Syria, and Saudi Arabia is irreconcilable with their broad similarity in lithosphere structure and composition and rather reflects a combination of factors including low-quality temperature data and insufficient knowledge on thermal rock properties.

  17. Unglazed photovoltaic-thermal collectors in combination with heat pumps and geothermal heat probes; Unverglaste photovoltaisch-thermische Kollektoren in Kombination mit Waermepumpen und Erdsonden

    Energy Technology Data Exchange (ETDEWEB)

    Bertram, E.; Stegmann, M.; Scheuren, J. [Institut fuer Solarenergieforschung GmbH Hameln/Emmerthal (ISFH), Emmerthal (Germany); Rosinski, C.; Kundmueller, K. [GEFGA mbH und Co. KG, Limburg (Germany)

    2010-07-01

    Unglazed Photovoltaic Thermal (PVT) collectors provide very high efficiency for heat and electricity generation at low temperatures. Therefore they are particularly suitable to support the heat source of heat pump systems, where low temperature heat is required. In this combination the PVT collector improves efficiency in two ways - of the heat pump by additional low temperature heat and of the photovoltaic by cooling. Between April and November 2009 an increase of 5% of photovoltaic electricity production and a high collector yield of 380 kWh/(m{sup 2} a) was measured on a pilot system. Of course, the improvement of the PV and heat pump efficiency depends strongly on the thermal PVT collector performance. In this context the performances of four different unglazed PVT collectors were measured and significant differences revealed. The conversion factor without electricity production varies from 0.33 to 0.73. Further, a model for unglazed PVT-collectors was developed. It is based on performance data of En 12975 and IEC 60904 only and considers thermal collector capacity and condensation effects. (orig.)

  18. Exergoeconomic performance optimization of an endoreversible intercooled regenerative Brayton combined heat and power plant coupled to variable-temperature heat reservoirs

    Directory of Open Access Journals (Sweden)

    Bo Yang, Lingen Chen, Fengrui Sun

    2012-01-01

    Full Text Available An endoreversible intercooled regenerative Brayton combined heat and power (CHP plant model coupled to variable-temperature heat reservoirs is established. The exergoeconomic performance of the CHP plant is investigated using finite time thermodynamics. The analytical formulae about dimensionless profit rate and exergy efficiency of the CHP plant with the heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are deduced. By taking the maximum profit rate as the objective, the heat conductance allocation among the five heat exchangers and the choice of intercooling pressure ratio are optimized by numerical examples, the characteristic of the optimal dimensionless profit rate versus corresponding exergy efficiency is investigated. When the optimization is performed further with respect to the total pressure ratio, a double-maximum profit rate is obtained. The effects of the design parameters on the double-maximum dimensionless profit rate and corresponding exergy efficiency, optimal total pressure ratio and optimal intercooling pressure ratio are analyzed in detail, and it is found that there exist an optimal consumer-side temperature and an optimal thermal capacitance rate matching between the working fluid and the heat reservoir, respectively, corresponding to a thrice-maximum dimensionless profit rate.

  19. Exergoeconomic performance optimization of an endoreversible intercooled regenerative Brayton combined heat and power plant coupled to variable-temperature heat reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bo; Chen, Lingen; Sun, Fengrui [College of Naval Architecture and Power, Naval University of Engineering, Wuhan 430033 (China)

    2012-07-01

    An endoreversible intercooled regenerative Brayton combined heat and power (CHP) plant model coupled to variable-temperature heat reservoirs is established. The exergoeconomic performance of the CHP plant is investigated using finite time thermodynamics. The analytical formulae about dimensionless profit rate and exergy efficiency of the CHP plant with the heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are deduced. By taking the maximum profit rate as the objective, the heat conductance allocation among the five heat exchangers and the choice of intercooling pressure ratio are optimized by numerical examples, the characteristic of the optimal dimensionless profit rate versus corresponding exergy efficiency is investigated. When the optimization is performed further with respect to the total pressure ratio, a double-maximum profit rate is obtained. The effects of the design parameters on the double-maximum dimensionless profit rate and corresponding exergy efficiency, optimal total pressure ratio and optimal intercooling pressure ratio are analyzed in detail, and it is found that there exist an optimal consumer-side temperature and an optimal thermal capacitance rate matching between the working fluid and the heat reservoir, respectively, corresponding to a thrice-maximum dimensionless profit rate.

  20. APPLICATION OF UNIT CONSUMPTION ANALYSIS IN THE 200 MW HEAT-SUPPLYING SYSTEM OF ZHENGZHOU COGENERATION PLANT%单耗分析理论在郑州热电厂200 MW供热系统中的应用

    Institute of Scientific and Technical Information of China (English)

    尚玉琴; 曹智; 宋之平

    2001-01-01

    在整理“供热系统”单耗分析的基础上,完善了热电联产供热系统的单耗计算方法,确定了热电联产供热系统各环节火 用效率的计算式,提出了一种确定供热系统设备折旧费的方法。利用单耗分析理论,对郑州热电厂出厂处及热用户处的供热煤耗和成本进行了计算和分析。%On the basis of collating the unit consumption analysis data of heat-supplying system,a formula to compute exergy-efficiency of each segment in heat-supplying system of a cogeneration plant has been deduced,the calculation method of electric and heat unit consumption being perfected,a method for determining the depreciation charge of equipments in heat-supplying system being presented,By using the unit consumption theory,the coal consumption and production cost of heat-supplying at the energy-outgoing point from Zhengzhou Cogeneration Plant and at the end of heat users have been calculated and analyzed.

  1. Stochastic Multicriteria Acceptability Analysis for Evaluation of Combined Heat and Power Units

    Directory of Open Access Journals (Sweden)

    Haichao Wang

    2014-12-01

    Full Text Available Combined heat and power (CHP is a promising technology that can contribute to energy efficiency and environmental protection. More CHP-based energy systems are planned for the future. This makes the evaluation and selection of CHP systems very important. In this paper, 16 CHP units representing different technologies are taken into account for multicriteria evaluation with respect to the end users’ requirements. These CHP technologies cover a wide range of power outputs and fuel types. They are evaluated from the energy, economy and environment (3E points of view, specifically including the criteria of efficiency, investment cost, electricity cost, heat cost, CO2 production and footprint. Uncertainties and imprecision are common both in criteria measurements and weights, therefore the stochastic multicriteria acceptability analysis (SMAA model is used in aiding this decision making problem. These uncertainties are treated better using a probability distribution function and Monte Carlo simulation in the model. Moreover, the idea of “feasible weight space (FWS” which represents the union of all preference information from decision makers (DMs is proposed. A complementary judgment matrix (CJM is introduced to determine the FWS. It can be found that the idea of FWS plus CJM is well compatible with SMAA and thus make the evaluation reliable.

  2. Generic Combined Heat and Power (CHP Model for the Concept Phase of Energy Planning Process

    Directory of Open Access Journals (Sweden)

    Satya Gopisetty

    2016-12-01

    Full Text Available Micro gas turbines (MGTs are regarded as combined heat and power (CHP units which offer high fuel utilization and low emissions. They are applied in decentralized energy generation. To facilitate the planning process of energy systems, namely in the context of the increasing application of optimization techniques, there is a need for easy-to-parametrize component models with sufficient accuracy which allow a fast computation. In this paper, a model is proposed where the non-linear part load characteristics of the MGT are linearized by means of physical insight of the working principles of turbomachinery. Further, it is shown that the model can be parametrized by the data usually available in spec sheets. With this model a uniform description of MGTs from several manufacturers covering an electrical power range from 30 k W to 333 k W can be obtained. The MGT model was implemented by means of Modelica/Dymola. The resulting MGT system model, comprising further heat exchangers and hydraulic components, was validated using the experimental data of a 65 k W MGT from a trigeneration energy system.

  3. DENSIFICATION OF WOOD VENEERS COMBINED WITH OIL-HEAT TREATMENT. PART I: DIMENSIONAL STABILITY

    Directory of Open Access Journals (Sweden)

    Chang-Hua Fang

    2011-02-01

    Full Text Available Although wood densification by compression improves wood mechanical strength, dimensional stability is often a problem due to compression recovery. Alternatively, oil-heat treatment (OHT improves wood dimensional stability and enhances resistance to biological attack. This study examined combined wood densification and OHT. Large wood veneer 700 × 700 mm specimens prepared with aspen (Populus tremuloides were densified using heat, steam, and pressure at 160ºC, 180ºC, and 200°C, respectively. OHT at 180ºC, 200ºC, and 220ºC for 1, 2, and 3h was then applied to the densified veneers. Results show that OHT efficiently improved dimensional stability and reduced compression set recovery. OHT temperature and duration markedly influenced the reduction of compression set recovery: the higher the OHT temperature and duration, the lower the recovery. Less than 5% recovery was obtained under various OHT conditions, and almost 0% recovery under some OHT conditions. Radial and tangential swellings of densified veneers were reduced dramatically. Compared to OHT duration, OHT temperature had a pronounced higher impact on radial and tangential swelling. Irreversible swelling (IS in the compression direction of densified veneers decreased after OHT, particularly with high temperature and long duration, and anti-swelling efficiency (ASE in the compression direction improved significantly.

  4. Design of Biomass Gasification and Combined Heat and Power Plant Based on Laboratory Experiments

    Science.gov (United States)

    Haydary, Juma; Jelemenský, Ľudovít

    Three types of wooden biomass were characterized by calorimetric measurements, proximate and elemental analysis, thermogravimetry, kinetics of thermal decomposition and gas composition. Using the Aspen steady state simulation, a plant with the processing capacity of 18 ton/h of biomass was modelled based on the experimental data obtained under laboratory conditions. The gasification process has been modelled in two steps. The first step of the model describes the thermal decomposition of the biomass based on a kinetic model and in the second step, the equilibrium composition of syngas is calculated by the Gibbs free energy of the expected components. The computer model of the plant besides the reactor model includes also a simulation of other plant facilities such as: feed drying employing the energy from the process, ash and tar separation, gas-steam cycle, and hot water production heat exchangers. The effect of the steam to air ratio on the conversion, syngas composition, and reactor temperature was analyzed. Employment of oxygen and air for partial combustion was compared. The designed computer model using all Aspen simulation facilities can be applied to study different aspects of biomass gasification in a Combined Heat and Power plant.

  5. Regulatory Compliance and Environmental Benefit Analysis of Combined Heat and Power (CHP Systems in Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Tien Tsai

    2013-01-01

    Full Text Available The energy conservation achieved by utilizing waste heat in the energy and industrial sectors has became more and more important after the energy crisis in the 1970s because it plays a vital role in the potential energy-efficiency improvement. In this regard, cogeneration (combined heat and power, CHP systems are thus becoming attractive due to the energy, economic, and environmental policies for pursuing stable electricity supply, sustainable development and environmental pollution mitigation in Taiwan. The objective of this paper is to present an updated analysis of CHP systems in Taiwan during the period from 1990 to 2010. The description in the paper is thus based on an analysis of electricity supply/consumption and its sources from CHP systems during the past two decades, and centered on two important regulations in compliance with CHP systems (i.e., Energy Management Law and Environmental Impact Assessment Act. Based on the total net power generation from CHP systems (i.e., 35,626 GWh in 2011, it was found that the carbon dioxide reduction benefits were estimated to be around 20,000 Gg.

  6. Simultaneous pasteurization and homogenization of human milk by combining heat and ultrasound: effect on milk quality.

    Science.gov (United States)

    Czank, Charles; Simmer, Karen; Hartmann, Peter E

    2010-05-01

    The combination of ultrasound and heat (thermoultrasound) is an emerging food preservation technique that retains higher quantities of bioactive components compared with current thermal pasteurization practice, but has not yet been assessed for pasteurizing human milk. Artificially contaminated human milk samples were treated with ultrasound (20 kHz, 150 watts) with and without heating. The retention of four human milk proteins was quantified by biochemical assay and laser scattering particle sizing was used to determine the extent of homogenization. While ultrasonic treatment was effective at inactivating Escherichia coli (D4 degrees C=5.94 min), Staphylococcus epidermidis exhibited resistance (D4 degrees C=16.01 min). Thermoultrasonic treatment was considerably more effective (Esch. coli D45 degrees C=1.74 min, D50 degrees C=0.89 min; Staph. epidermidis D45 degrees C=2.08 min, D50 degrees C=0.94 minutes) with a predicted retention (2.8 min treatment, 50 degrees C) of secretory IgA lysozyme, lactoferrin and bile salt stimulated lipase of 91, 80, 77, and 45%, respectively. Homogenization of the milk samples occurred after 5 min and 2 min of ultrasonic and thermoultrasonic treatment, respectively. Thermoultrasonic treatment is an effective method for pasteurizing donor human milk and retaining a greater proportion of bioactive components compared with current practices. However, further studies are required to assess the practicality of applying this technique routinely to donor human milk.

  7. Conjugate Heat Transfer Study of Combined Impingement and Showerhead Film Cooling Near NGV Leading Edge

    Directory of Open Access Journals (Sweden)

    Dileep Chandran

    2015-01-01

    Full Text Available A computational and experimental study is carried out on the leading edge region of a typical gas turbine NGV, cooled by a combination of impingement and showerhead film cooling. A detailed flow and conjugate heat transfer study has revealed the complex flow structure owing to the coolant-mainstream interaction and the influence of vane material thermal conductivity. The local effectiveness values obtained by the computations agreed well with the experimental data from IR thermography. The effect of blowing ratio on the overall effectiveness is found to be strongly dependent on the vane material conductivity. The effect of blowing ratio is also found to be different towards the pressure and suction sides of the stagnation region. However, the overall effectiveness is found to decrease by about 12% and 6% for low and high conducting materials, respectively, with an increase in mainstream Reynolds number from Re=4.8×105 to 14.4×105.

  8. The potential impact of policies to promote combined heat and power in US industry

    Energy Technology Data Exchange (ETDEWEB)

    Lemar, P.L. Jr. [Resource Dynamics Corp., Vienna, VA (USA)

    2001-11-01

    The paper reviews a portion of the study Scenarios for a Clean Energy Future that examined the impact that combined heat and power (CHP) technologies could have on US industry. This study explored how different public policies and programs could affect the energy use and environmental impact of a wide range of CHP technologies, including those currently under development. It concluded that policies can be developed to reduce carbon emissions, increase energy efficiency, and improve fuel diversity within the US industrial sector, at little or no additional cost to the US economy. These policies sought to either improve the cost and performance of CHP technology or to reduce financial, siting or utility barriers to adoption. The most advanced set of policies has the potential to reduce carbon emission by over 26 million metric ton by the year 2010, all by removing barriers to applications of CHP that are economically achievable by industry. 14 refs., 4 figs., 14 tabs.

  9. Demonstration of combined zero-valent iron and electrical resistance heating for in situ trichloroethene remediation.

    Science.gov (United States)

    Truex, M J; Macbeth, T W; Vermeul, V R; Fritz, B G; Mendoza, D P; Mackley, R D; Wietsma, T W; Sandberg, G; Powell, T; Powers, J; Pitre, E; Michalsen, M; Ballock-Dixon, S J; Zhong, L; Oostrom, M

    2011-06-15

    The effectiveness of in situ treatment using zero-valent iron (ZVI) for nonaqueous phase or significant sediment-associated contaminant mass can be limited by relatively low rates of mass transfer to bring contaminants in contact with the reactive media. For a field test in a trichloroethene (TCE) source area, combining moderate-temperature subsurface electrical resistance heating with in situ ZVI treatment was shown to accelerate TCE treatment by a factor of about 4 based on organic daughter products and a factor about 8 based on chloride concentrations. A mass-discharge-based analysis was used to evaluate reaction, dissolution, and volatilization processes at ambient groundwater temperature (~10 °C) and as temperature was increased up to about 50 °C. Increased reaction and contaminant dissolution were observed with increased temperature, but vapor- or aqueous-phase migration of TCE out of the treatment zone was minimal during the test because reactions maintained low aqueous-phase TCE concentrations.

  10. EVALUATION OF EVACUATED TUBULAR SOLAR COLLECTORS FOR LARGE SDHW SYSTEMS AND COMBINED SPACE HEATING SYSTEMS

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    . Based on thesemodels, the thermal performance of large solar domestic hot water (DHW) systems and combined domestichot water and space heating systems with the four evacuated tubular collectors was determined. To make acomparison with traditional flat-plate collectors, similar simulations were also...... carried out for systems with atypical flat-plate collector. The results show that the thermal advantage of evacuated tubular collectors variesgreatly from system to system, and increases with the solar fraction. Furthermore, the higher the operationtemperature of the collector in the system is......In the present study, detailed investigations on evacuated tubular solar collectors for large solarheating systems have been carried out. Four types of evacuated tubular solar collectors were used in theinvestigation. Based on laboratory tests, simulation models for the collectors were determined...

  11. Study of temperature characterization of agricultural waste in the development of stove for combine heat power

    Science.gov (United States)

    Yulianto, Muhamad; Agustina, Sri Endah; Hartulistiyoso, Edy; Nelwan, Leopold Oscar; Nurlela

    2017-03-01

    Indonesia is one of tropical country in the world, therefore biomass product can find a lot in Indonesia. In the other side, waste of agricultural product is one of biomass resources which is can be converting to energy using Combine Heat Power for the example. In this paper, will be discussed about the temperature characterization due to influence of feeding rate and air flow rate. The contribution of this paper will show the temperature achievement of flue gas as the result of direct combustion in a stove. The research conducted using coconut shell as raw fuel material with varying feed rate and air flow rate. In this research also use the excess air to know the effect. The result show that the temperature of flue gas in direct combustion of coconut shell can reach of 520°C and temperature at combustion chamber reach 840°C. This achievement is occurring in the certain variation of experiment.

  12. Physiological and metabolic changes of purslane (Portulaca oleracea L. in response to drought, heat and combined stresses

    Directory of Open Access Journals (Sweden)

    Rui eJin

    2016-01-01

    Full Text Available Purslane (Portulaca oleracea L. is a fleshy herbaceous plant. So far, little information is available on the response of this plant to combined drought and heat stress. In this study, changes in physiological and metabolic levels were characterized after treatments with drought, heat and combined stresses. Both individual and combined stress treatments increased malondialdehyde (MDA, electrolyte leakage (EL, O2•− and activities of superoxide dismutase (SOD, peroxidase (POD, while declined chlorophyll content. No significant differences were found between control and treatments in leaf water content (LWC and catalase (CAT activity. Additionally, 37 metabolic compounds were detected in purslane. Through pathway analysis, 17 metabolites were directly involved in the glycolysis metabolic pathway. The present study indicated that combined drought and heat stress caused more serious damage in purslane than individual stress. To survive, purslane has a high capability to cope with environmental stress conditions through activation of physiological and metabolic pathways.

  13. Evaluation of Combined Heat and Power (CHP Systems Using Fuzzy Shannon Entropy and Fuzzy TOPSIS

    Directory of Open Access Journals (Sweden)

    Fausto Cavallaro

    2016-06-01

    Full Text Available Combined heat and power (CHP or cogeneration can play a strategic role in addressing environmental issues and climate change. CHP systems require less fuel than separate heat and power systems in order to produce the same amount of energy saving primary energy, improving the security of the supply. Because less fuel is combusted, greenhouse gas emissions and other air pollutants are reduced. If we are to consider the CHP system as “sustainable”, we must include in its assessment not only energetic performance but also environmental and economic aspects, presenting a multicriteria issue. The purpose of the paper is to apply a fuzzy multicriteria methodology to the assessment of five CHP commercial technologies. Specifically, the combination of the fuzzy Shannon’s entropy and the fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS approach will be tested for this purpose. Shannon’s entropy concept, using interval data such as the α-cut, is a particularly suitable technique for assigning weights to criteria—it does not require a decision-making (DM to assign a weight to the criteria. To rank the proposed alternatives, a fuzzy TOPSIS method has been applied. It is based on the principle that the chosen alternative should be as close as possible to the positive ideal solution and be as far as possible from the negative ideal solution. The proposed approach provides a useful technical–scientific decision-making tool that can effectively support, in a consistent and transparent way, the assessment of various CHP technologies from a sustainable point of view.

  14. Novel Direct Steelmaking by Combining Microwave, Electric Arc, and Exothermal Heating Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Xiaodi Huang; Dr. J. Y. Hwang

    2005-03-28

    Steel is a basic material broadly used by perhaps every industry and individual. It is critical to our nation's economy and national security. Unfortunately, the American steel industry is losing competitiveness in the world steel production field. There is an urgent need to develop the next generation of steelmaking technology for the American steel industry. Direct steelmaking through the combination of microwave, electric arc, and exothermal heating is a revolutionary change from current steelmaking technology. This technology can produce molten steel directly from a shippable agglomerate, consisting of iron oxide fines, powdered coal, and ground limestone. This technology is projected to eliminate many current intermediate steelmaking steps including coking, pellet sintering, blast furnace (BF) ironmaking, and basic oxygen furnace (BOF) steelmaking. This technology has the potential to (a) save up to 45% of the energy consumed by conventional steelmaking; (b) dramatically reduce the emission of CO{sub 2}, SO{sub 2}, NO{sub x}, VOCs, fine particulates, and air toxics; (c) substantially reduce waste and emission control costs; (d) greatly lower capital cost; and (e) considerably reduce steel production costs. This technology is based on the unique capability of microwaves to rapidly heat steelmaking raw materials to elevated temperature, then rapidly reduce iron oxides to metal by volumetric heating. Microwave heating, augmented with electric arc and exothermal reactions, is capable of producing molten steel. This technology has the components necessary to establish the ''future'' domestic steel industry as a technology leader with a strong economically competitive position in world markets. The project goals were to assess the utilization of a new steelmaking technology for its potential to achieve better overall energy efficiency, minimize pollutants and wastes, lower capital and operating costs, and increase the competitiveness of the

  15. Sustainable heat for apartment buildings in Haarlem, Netherlands; Duurzamewarmte voor Haarlemse flats

    Energy Technology Data Exchange (ETDEWEB)

    Beltman, J.; Schumacher, R. [CEA, Rotterdam (Netherlands)

    2002-12-01

    By means of an innovative combination of solar collectors, heat pumps and underground heat storage it is possible to heat 382 apartment buildings in the winter by using solar energy stored in the summer. The construction for this 2 MW project in district Schalkwijk in Haarlem, Netherlands is in full progress. [Dutch] Een innovatieve combinatie van zonnecollectoren, warmtepompen en ondergrondse warmteopslag maakt het mogelijk 382 flatwoningen uit de jaren vijftig in de winter te verwarmen met zonne-energie die in de zomer is opgeslagen. De bouwwerkzaamheden voor dit 2 MW-project in de Haarlemse Schalkwijk zijn in volle gang.

  16. Combined lock-in thermography and heat flow measurements for analysing heat dissipation during fatigue crack propagation

    Directory of Open Access Journals (Sweden)

    J. Bär

    2015-10-01

    Full Text Available During fatigue crack propagation experiments with constant force as well as constant stress intensity lock in thermography and heat flow measurements with a new developed peltier sensor have been performed. With lock in thermography space resolved measurements are possible and the evaluation allows to distinguish between elastic and dissipated energies. The specimens have to be coated with black paint to enhance the emissivity. The thickness of the coating influences the results and therefore quantitative measurements are problematic. The heat flow measurements are easy to perform and provide quantitative results but only integral in an area given by the used peltier element. To get comparable results the values measured with thermography were summarized in an area equivalent to that of the peltier element. The experiments with constant force show a good agreement between the thermography and the heat flow measurements. In case of the experiments with a constant stress intensity some differences become visible. Whereas the thermography measurements show a linear decrease of the signal with rising crack length, the heat flow measurements show a clearly nonlinear dependency. Obviously the measured energies in thermography and peltier based heat flow measurement are not comparable

  17. Feasibility study of 5MW superconducting wind turbine generator

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Jensen, Bogi Bech; Seiler, E.

    2011-01-01

    The feasibility of installing a direct drive superconducting generator in the 5MW reference offshore wind turbine of the National Renewable Energy Laboratory (NREL) has been examined. The engineering current densities Je obtained in a series of race track coils have been combined with magnetization...

  18. Energy management strategies for combined heat and electric power micro-grid

    Directory of Open Access Journals (Sweden)

    Barbarić Marina

    2016-01-01

    Full Text Available The increasing energy production from variable renewable energy sources such as wind and solar has resulted in several challenges related to the system reliability and efficiency. In order to ensure the supply-demand balance under the conditions of higher variability the micro-grid concept of active distribution networks arising as a promising one. However, to achieve all the potential benefits that micro-gird concept offer, it is important to determine optimal operating strategies for micro-grids. The present paper compares three energy management strategies, aimed at ensuring economical micro-grid operation, to find a compromise between the complexity of strategy and its efficiency. The first strategy combines optimization technique and an additional rule while the second strategy is based on the pure optimization approach. The third strategy uses model based predictive control scheme to take into account uncertainties in renewable generation and energy consumption. In order to compare the strategies with respect to cost effectiveness, a residential micro-grid comprising photovoltaic modules, thermal energy storage system, thermal loads, electrical loads as well as combined heat and power plant, is considered.

  19. Storage stability of lycopene in tomato juice subjected to combined pressure-heat treatments.

    Science.gov (United States)

    Gupta, Rockendra; Balasubramaniam, V M; Schwartz, Steven J; Francis, David M

    2010-07-28

    A study was conducted to characterize the storage stability of lycopene in hot-break tomato juice prepared from two different cultivars and processed by various pressure-heat combinations. Samples were subjected to pressure assisted thermal processing (PATP; 600 MPa, 100 degrees C, 10 min), high pressure processing (HPP; 700 MPa, 45 degrees C, 10 min), and thermal processing (TP; 0.1 MPa, 100 degrees C, 35 min). Processed samples were stored at 4, 25, and 37 degrees C for upto 52 weeks. HPP and PATP treatments significantly improved the extractability of lycopene over TP and control. All-trans lycopene was found to be fairly stable to isomerization during processing, and the cis isomer content of the control and processed juice did not differ significantly. During storage, lycopene degradation varied as a function of the cultivar, processing method, storage temperature, and time. This study shows that combined pressure-temperature treatments could be an attractive alternative to thermal sterilization for preserving tomato juice quality.

  20. Heat-induced-radiolabeling and click chemistry: A powerful combination for generating multifunctional nanomaterials

    Science.gov (United States)

    Wilks, Moses Q.; El Fakhri, Georges; Normandin, Marc D.; Kaittanis, Charalambos; Josephson, Lee

    2017-01-01

    A key advantage of nanomaterials for biomedical applications is their ability to feature multiple small reporter groups (multimodality), or combinations of reporter groups and therapeutic agents (multifunctionality), while being targeted to cell surface receptors. Here a facile combination of techniques for the syntheses of multimodal, targeted nanoparticles (NPs) is presented, whereby heat-induced-radiolabeling (HIR) labels NPs with radiometals and so-called click chemistry is used to attach bioactive groups to the NP surface. Click-reactive alkyne or azide groups were first attached to the nonradioactive clinical Feraheme (FH) NPs. Resulting “Alkyne-FH” and “Azide-FH” intermediates, like the parent NP, tolerated 89Zr labeling by the HIR method previously described. Subsequently, biomolecules were quickly conjugated to the radioactive NPs by either copper-catalyzed or copper-free click reactions with high efficiency. Synthesis of the Alkyne-FH or Azide-FH intermediates, followed by HIR and then by click reactions for biomolecule attachment, provides a simple and potentially general path for the synthesis of multimodal, multifunctional, and targeted NPs for biomedical applications. PMID:28225818

  1. 600MW Supercritical Unit Heat System Heater Running Economy Analysis%600MW超临界机组回热系统加热器运行经济性分析

    Institute of Scientific and Technical Information of China (English)

    丁之淇

    2015-01-01

    通过实际测量6000MW级超临界机组高、低压加热器运行的各项参数,分析有关参数对机组经济性定量影响,并且对高、低压加热器运行经济性进行了分析和评估,同时提出了高、低压加热器水位调整的的试验准备、试验方法、热控定值修改等技术措施和建议,提高机组运行经济性。%Through the 6000 MW supercritical unit level high and low heater operation of the variousparame⁃ters, an analysis of the parameters quantitative influence on the unit economy, and the high and low heater running economy are analyzed and evaluated, at the same time puts forward the high and low heater water level adjustment test preparation, test method, thermal control fixed value modification and other technical measures and Suggestions for manufacturing and operation maintenance unit reference.

  2. Heat storage containers filled with the combination of a eutectic salt and a non-biodegradable filler material

    Energy Technology Data Exchange (ETDEWEB)

    Schoenfelder, J.L.

    1980-09-23

    A heat storage article adapted for prevention of stratification of heat storage materials, such as eutectic salts contained within the container element. The article is comprised of a heavy thermally conductive container with an internal cavity. The internal cavity of the container is substantially completely filled with a combination of a non-biodegradable filler material such as glass fiber insulation and a eutectic salt.

  3. Aero-Elastic Optimization of a 10 MW Wind Turbine

    DEFF Research Database (Denmark)

    Zahle, Frederik; Tibaldi, Carlo; Verelst, David Robert;

    2015-01-01

    This article describes a multi-disciplinary optimization and analysis tool for wind turbines that is based on the open-source framework OpenMDAO. Interfaces to several simulation codes have been implemented which allows for a wide variety of problem formulations and combinations of models....... In this article concurrent aeroelastic optimization of a 10 MW wind turbine rotor is carried out with respect to material distribution distribution and planform. The optimizations achieve up to 13% mass reduction while maintaining the same power production compared to the baseline DTU 10MW RWT....

  4. Laboratory Evaluation of Gas-Fired Tankless and Storage Water Heater Approaches to Combination Water and Space Heating

    Energy Technology Data Exchange (ETDEWEB)

    Kingston, T. [Gas Technology Inst., Des Plaines, IL (United States); Scott, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2013-03-01

    Homebuilders are exploring more cost-effective combined space and water heating systems (combo systems) with major water heater manufacturers that are offering pre-engineered forced air space heating combo systems. In this project, unlike standardized tests, laboratory tests were conducted that subjected condensing tankless and storage water heater based combo systems to realistic, coincidental space and domestic hot water loads and found that the tankless combo system maintained more stable DHW and space heating temperatures than the storage combo system, among other key findings.

  5. Working fluids of a low-temperature geothermally-powered Rankine cycle for combined power and heat generation system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel combined power and heat generation system was investigated in this study. This system consists of a low-temperature geothermally-powered organic Rankine cycle (ORC) subsystem, an intermediate heat exchanger and a commercial R134a-based heat pump subsystem. The advantages of the novel combined power and heat generation system are free of using additional cooling water circling system for the power generation subsystem as well as maximizing the use of thermal energy in the low-temperature geothermal source. The main purpose is to identify suitable working fluids (wet, isentropic and dry flu-ids) which may yield high PPR (the ratio of power produced by the power generation subsystem to power consumed by the heat pump subsystem) value and QQR (the ratio of heat supplied to the user to heat produced by the geothermal source) value. Parameters under investigation were evaporating temperature, PPR value and QQR value. Results indicate that there exits an optimum evaporating temperature to maximize the PPR value and minimize the QQR value at the same time for individual fluid. And dry fluids show higher PPR values but lower QQR values. NH3 and R152a outstand among wet fluids. R134a out-stands among isentropic fluids. R236ea, R245ca, R245fa, R600 and R600a outstand among dry fluids. R236ea shows the highest PPR value among the recommended fluids.

  6. Optimization of Combine Heat and Power Plants in the Russian Wholesale Power Market Conditions

    Directory of Open Access Journals (Sweden)

    I. A. Chuchueva

    2015-01-01

    Full Text Available The paper concerns the relevant problem to optimize the combine heat and power (CHP plants in the Russian wholesale power market conditions. Since 1975 the CHP plants specialists faced the problem of fuel rate or fuel cost reduction while ensuring the fixed level of heat and power production. The optimality criterion was the fuel rate or fuel cost which has to be minimized. Produced heat and power was paid by known tariff. Since the power market started in 2006 the power payment scheme has essentially changed: produced power is paid by market price. In such condition a new optimality criterion the paper offers is a profit which has to be maximized for the given time horizon. Depending on the optimization horizon the paper suggests four types of the problem urgency, namely: long-term, mid-term, short-term, and operative optimization. It clearly shows that the previous problem of fuel cost minimization is a special case of profit maximization problem. To bring the problem to the mixed-integer linear programming problem a new linear characteristic curves of steam and gas turbine are introduced. Error of linearization is 0.6%. The formal statement of the problem of short-term CHP plants optimization in the market conditions is offered. The problem was solved with IRM software (OpenLinkInternational for seven power plants of JSC “Quadra”: Dyagilevskaya CHP, Kurskaya CHP-1, Lipetskaya CHP-2, Orlovskaya CHP, Kurskaya CHP NWR, Tambovskaya CHP, and Smolenskaya CHP-2.The conducted computational experiment showed that a potential profit is between 1.7% and 4.7% of the fuel cost of different CHP plants and depends on the power plant operation conditions. The potential profit value is 2–3 times higher than analogous estimations, which were obtained solving fuel cost minimization problem. The perspectives of the work are formalization of mid-term and long-term CHP plants optimization problem and development of domestic software for the new problem

  7. Inverse conjugate mixed convection in a vertical substrate with protruding heat sources: a combined experimental and numerical study

    Science.gov (United States)

    Ahamad, Shaik Imran; Balaji, C.

    2016-06-01

    This paper reports the results of a combined numerical and experimental study to estimate the heat inputs of three protruding heat sources of the same size placed on a vertically placed PCB board of height 150 mm, depth 250 mm, and thickness 5 mm. First, limited measurements of temperatures were recorded at eight locations along the height of the back of the PCB board for different (and known) values of heat inputs of the protruding heat sources and different velocities. These were followed by three-dimensional calculations of fluid flow and conjugate heat transfer for various heat transfer coefficients on the backside of the PCB board. The difference between the CFD predicted and experimentally measured temperature distributions on the back of the PCB board was minimized using least squares and the best value of heat transfer coefficient was obtained. Using this `data assimilated' CFD model, detailed CFD simulations were done for various values of heat input values and Reynolds numbers (each of these can be different from one another) of the flow. The temperatures at the same eight locations at the back of the PCB board were noted. An artificial neural network was then developed with ten inputs (eight temperatures together with the input velocity and the ambient temperature) to estimate the three outputs (three heat inputs) after carrying out extensive studies on the architecture of the network. This inverse solution was then tested with experiments for validating the ANN approach to solve the inverse conjugate heat transfer problem. Finally, with the ANN estimated heat inputs, CFD simulations were again run to compare the temperature distribution at the back of the PCB board with measurements.

  8. Combined active and passive heat exposure induced heat acclimation in a soccer referee before 2014 FIFA World Cup.

    Science.gov (United States)

    Ruddock, A D; Thompson, S W; Hudson, S A; James, C A; Gibson, O R; Mee, J A

    2016-01-01

    The 2014 FIFA World Cup was held in Brazil, where the climatic conditions presented a significant thermoregulatory and perceptual challenge to those unfamiliar with the heat and humidity. This case report documents the adaptation induced by a novel mixed methods (isothermic and passive) heat acclimation (HA) regime for a northern European professional soccer match official prior to the tournament. The intervention involved 13 HA sessions over an 18 day period comprising five isothermic HA sessions whereby intermittent running was used to target and maintain tympanic temperature (Tytemp) at 38 °C for 90 min, and seven passive HA sessions of 48 °C water bathing for 30 min. The athlete performed a heat stress test (HST) (35 min running at four incremental intensities in 30 °C) and a repeated high-intensity running test (as many 30 s self-paced efforts as possible, to a maximum of 20, with 30 s passive recovery) before and after the intervention. The mixed methods HA regime increased plasma volume (+7.1 %), and sweat loss (+0.9 L h(-1)), reduced exercising Tytemp (-0.6 °C), and mean body temperature (-0.5 °C). High-intensity running performance improved after HA (+29 %), as did the perception of thermal comfort during exercise (-0.3 units). This data evidences the effectiveness of a practical, mixed methods HA strategy, remotely implemented around training and competition, at inducing the heat acclimation phenotype in a high-level soccer match official.

  9. Physicochemical and crystalline properties of heat-moisture-treated rice starch: combined effects of moisture and duration of heating.

    Science.gov (United States)

    Kong, Xiangli; Qiu, Dan; Ye, Xiaoting; Bao, Jinsong; Sui, Zhongquan; Fan, Jiewei; Xiang, Wenzhou

    2015-11-01

    Currently there is much interest in the application of physical modification techniques such as heat-moisture treatment (HMT). The effects of HMT on normal and waxy rice starches, subject to different levels of moisture content and duration of heating, were investigated. Water solubility index (determined at 90 °C) decreased after HMT for normal and waxy rice starches, while swelling power (determined at 90 °C) showed inconsistent results (decrease for normal type, increase for waxy type) after HMT. Values in pasting parameters of normal and waxy rice starch increased initially, but the extent of increase slowed down with moisture content and length of treatment increasing. HMT decreased gelatinization temperatures with 4 h and 8 h treatment, but when length of treatment was prolonged to 16 h gelatinization temperature increased. Degree of crystallinity decreased for all treatments, and decreased much more at higher levels of moisture content. Variations in levels of moisture content and duration of heating had significant effects on physicochemical and crystalline properties to different extents. © 2014 Society of Chemical Industry.

  10. Quantifying the effects of heating temperature, and combined effects of heating medium pH and recovery medium pH on the heat resistance of Salmonella typhimurium.

    Science.gov (United States)

    Leguérinel, I; Spegagne, I; Couvert, O; Coroller, L; Mafart, P

    2007-05-01

    The influence of heating treatment temperature, pH of heating and recovery medium on the survival kinetics of Salmonella typhimurium ATCC 13311 is studied and quantified. From each non-log linear survival curve, Weibull model parameters were estimated. An average shape parameter value of 1.67 was found, which is characteristic of downward concavity curves and is in agreement with values estimated from other S. typhimurium strains. Bigelow type models quantifying the heating temperature, heating and recovery medium pH influences are fitted on scale parameter delta data (time of first decimal reduction), which reflects the bacterial heat resistance. The estimate of z(T) (4.64 degrees C) is in the range of values given in the literature for this species. The influence of pH of the heating medium on the scale parameter (z(pH): 8.25) is lower than that of the recovery pH medium influence (z(')(pH): 3.65).

  11. The combined effect of salinity and heat reveals a specific physiological, biochemical and molecular response in tomato plants.

    Science.gov (United States)

    Rivero, Rosa M; Mestre, Teresa C; Mittler, Ron; Rubio, Francisco; Garcia-Sanchez, Francisco; Martinez, Vicente

    2014-05-01

    Many studies have described the response mechanisms of plants to salinity and heat applied individually; however, under field conditions some abiotic stresses often occur simultaneously. Recent studies revealed that the response of plants to a combination of two different stresses is specific and cannot be deduced from the stresses applied individually. Here, we report on the response of tomato plants to a combination of heat and salt stress. Interestingly, and in contrast to the expected negative effect of the stress combination on plant growth, our results show that the combination of heat and salinity provides a significant level of protection to tomato plants from the effects of salinity. We observed a specific response of plants to the stress combination that included accumulation of glycine betaine and trehalose. The accumulation of these compounds under the stress combination was linked to the maintenance of a high K(+) concentration and thus a lower Na(+) /K(+) ratio, with a better performance of the cell water status and photosynthesis as compared with salinity alone. Our findings unravel new and unexpected aspects of the response of plants to stress combination and provide a proposed list of enzymatic targets for improving crop tolerance to the abiotic field environment.

  12. Lightweight MgB2 superconducting 10 MW wind generator

    Science.gov (United States)

    Marino, I.; Pujana, A.; Sarmiento, G.; Sanz, S.; Merino, J. M.; Tropeano, M.; Sun, J.; Canosa, T.

    2016-02-01

    The offshore wind market demands a higher power rate and more reliable turbines in order to optimize capital and operational costs. The state-of-the-art shows that both geared and direct-drive conventional generators are difficult to scale up to 10 MW and beyond due to their huge size and weight. Superconducting direct-drive wind generators are considered a promising solution to achieve lighter weight machines. This work presents an innovative 10 MW 8.1 rpm direct-drive partial superconducting generator using MgB2 wire for the field coils. It has a warm iron rotor configuration with the superconducting coils working at 20 K while the rotor core and the armature are at ambient temperature. A cooling system based on cryocoolers installed in the rotor extracts the heat from the superconducting coils by conduction. The generator's main parameters are compared against a permanent magnet reference machine, showing a significant weight and size reduction. The 10 MW superconducting generator concept will be experimentally validated with a small-scale magnetic machine, which has innovative components such as superconducting coils, modular cryostats and cooling systems, and will have similar size and characteristics as the 10 MW generator.

  13. Technical Analysis of Installed Micro-Combined Heat and Power Fuel-Cell System

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P.; Makhmalbaf, Atefe

    2014-10-31

    Combined heat and power fuel cell systems (CHP-FCSs) provide consistent electrical power and hot water with greater efficiency and lower emissions than alternative sources. These systems can be used either as baseload, grid-connected, or as off-the-grid power sources. This report presents a technical analysis of 5 kWe CHP-FCSs installed in different locations in the U.S. At some sites as many as five 5 kWe system is used to provide up to 25kWe of power. Systems in this power range are considered “micro”-CHP-FCS. To better assess performance of micro-CHP-FCS and understand their benefits, the U.S. Department of Energy worked with ClearEdge Power to install fifteen 5-kWe PBI high temperature PEM fuel cells (CE5 models) in the commercial markets of California and Oregon. Pacific Northwest National Laboratory evaluated these systems in terms of their economics, operations, and technical performance. These units were monitored from September 2011 until June 2013. During this time, about 190,000 hours of data were collected and more than 17 billion data points were analyzed. Beginning in July 2013, ten of these systems were gradually replaced with ungraded systems (M5 models) containing phosphoric acid fuel cell technology. The new units were monitored until June 2014 until they went offline because ClearEdge was bought by Doosan at the time and the new manufacturer did not continue to support data collection and maintenance of these units. During these two phases, data was collected at once per second and data analysis techniques were applied to understand behavior of these systems. The results of this analysis indicate that systems installed in the second phase of this demonstration performed much better in terms of availability, consistency in generation, and reliability. The average net electrical power output increased from 4.1 to 4.9 kWe, net heat recovery from 4.7 to 5.4 kWth, and system availability improved from 94% to 95%. The average net system electric

  14. Optimal Energy Management of Combined Cooling, Heat and Power in Different Demand Type Buildings Considering Seasonal Demand Variations

    Directory of Open Access Journals (Sweden)

    Akhtar Hussain

    2017-06-01

    Full Text Available In this paper, an optimal energy management strategy for a cooperative multi-microgrid system with combined cooling, heat and power (CCHP is proposed and has been verified for a test case of building microgrids (BMGs. Three different demand types of buildings are considered and the BMGs are assumed to be equipped with their own combined heat and power (CHP generators. In addition, the BMGs are also connected to an external energy network (EEN, which contains a large CHP, an adsorption chiller (ADC, a thermal storage tank, and an electric heat pump (EHP. By trading the excess electricity and heat energy with the utility grid and EEN, each BMG can fulfill its energy demands. Seasonal energy demand variations have been evaluated by selecting a representative day for the two extreme seasons (summer and winter of the year, among the real profiles of year-round data on electricity, heating, and cooling usage of all the three selected buildings. Especially, the thermal energy management aspect is emphasized where, bi-lateral heat trading between the energy supplier and the consumers, so-called energy prosumer concept, has been realized. An optimization model based on mixed integer linear programming has been developed for minimizing the daily operation cost of the EEN while fulfilling the energy demands of the BMGs. Simulation results have demonstrated the effectiveness of the proposed strategy.

  15. Reliability Indices Utlization in Combined Heat and Power ( CHP Optimal Operation

    Directory of Open Access Journals (Sweden)

    Hamed Hosseinnia

    2014-12-01

    Full Text Available The reason for using cogeneration more that heat and power separately is that, it is more efficient. In this paper the goal is finding the optimized CHP system utility size and thermal storage considering reliability limits of boiler and grid connected bus. Loss of Load Expectation (LOLE and Expected energy not supplied (EENS are considered as two reliability indices to insure the security of operation. Non-sequential Monte Carlo simulation method is introduced to the reliability assessment of CHP, and a normal distribution electrical load model is built to simulate the hourly electrical load. CHP model combined with a two-state reliability model is applied to Monte Carlo simulation method, and results show that the CHP reliability model works well with non-sequential Monte Carlo simulation. Non-Sequential Monte Carlo method is used to generate scenarios. Also in order to reduce computation time and due to the large number of scenarios, a scenario reduction technique is used. GAMS software is used for optimization process.

  16. Transient Stability Improvement for Combined Heat and Power System Using Load Shedding

    Directory of Open Access Journals (Sweden)

    Hung-Cheng Chen

    2014-01-01

    Full Text Available The purpose of the paper is to analyze and improve the transient stability of an industrial combined heat and power (CHP system in a high-tech science park in Taiwan. The CHP system installed two 161 kV/161 kV high-impendence transformers to connect with Taipower System (TPS for both decreasing the short-circuit fault current and increasing the fault critical clearing time. The transient stabilities of three types of operation modes in CHP units, 3G1S, 2G1S, and 1G1S, are analyzed. Under the 3G1S operation mode, the system frequency is immediately restored to 60 Hz after tie line tripping with the TPS. Under the 1G1S and 2G1S operation modes, the system frequencies will continuously decrease and eventually become unstable. A novel transient stability improvement approach using load shedding technique based on the change in frequency is proposed to improve the transient stability.

  17. Preservation of avocados (var. Fuerte) by heat and irradiation combined treatment

    Energy Technology Data Exchange (ETDEWEB)

    Karmelic, J. (Instituto de Investigaciones Tecnologicas, Santiago (Chile)); Rubio, T.; Urbina, Y.M.C. (Comision Chilena de Energia Nuclear, Santiago. Dept. de Aplicaciones Nucleares)

    1983-11-01

    The high national production of avocados expected for the next years asks for the opening of new markets to be reached by ship. For this reason, it is necessary to increase the shelf-life of avocados for a period of 40 days at least. Therefore, the effect of combined treatment: mild heat (46/sup 0/C, 20 min) and low radiation doses (25, 50, 100 Gy), in avocados is studied. Additional parameters considered in this study are: wrapping with PVC film, storage temperature (7/sup 0/C and room temperature), two different degrees of ripening. Best results are obtained with the lowest dose (25 Gy) and low degree of ripening of wrapped avocados, stored at 7/sup 0/C. After 40 days, 98,6% of the avocados were well preserved and 85,5% after 50 days. When compared with non irradiated samples, avocados irradiated with 25 Gy show 25% and 34% higher undamaged percentage after 40 and 50 days of storage; respectively. A negative effect is obtained when irradiation is applied to avocados with a high degree of ripening. Room temperature is not suitable for a long storage period of avocados.

  18. Combined heating and chemical treatment for oil recovery from aging crude oil.

    Science.gov (United States)

    Hou, Chunjuan; Jiang, Qingzhe; Song, Zhaozheng; Tan, Guorong; Shi, Zhan

    2016-07-01

    With increasing use of chemical oil displacement agents in tertiary recovery and the application of various demulsifiers for crude oil dehydration, a large amount of aging crude oil containing a high ratio of water is produced, and it is very difficult for processing and utilisation. In this article, we chose aging crude oil samples from a union station in an oilfield in China. Sample composition was analysed to demonstrate that the key of aging crude oil dehydration is the removal of solid impurities. Thus, an efficient method of combining heating and chemical treatments was developed to treat aging crude oil. It includes two steps: The first step is washing of aging crude oil with hot water with sodium dodecylbenzene sulfonate; the second step is chemical demulsification of the above mixture with hydrochloric acid and sodium chloride solution. The result showed that 2.9% of solid impurities and 29.2% of water were removed in the first step; 27.2% of oil, 24.3% of water, and 3.47% of solid impurities in the aging crude oil were recycled in the second step. A total 87.07% of aging crude oil could be solved with this method. The present two-step treatment method can ensure that the dehydration process runs normally and efficiently in the union station, making it a promising method in the recycling of aging crude oil. © The Author(s) 2016.

  19. Demonstration of Combined Zero-Valent Iron and Electrical Resistance Heating for In Situ Trichloroethene Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Macbeth, Tamzen; Vermeul, Vincent R.; Fritz, Brad G.; Mendoza, Donaldo P.; Mackley, Rob D.; Wietsma, Thomas W.; Sandberg, Greg; Powell, Thomas; Powers, Jeff; Pitre, Emile; Michalsen, Mandy M.; Ballock-Dixon, Sage; Zhong, Lirong; Oostrom, Martinus

    2011-06-27

    The effectiveness of in situ treatment using zero-valent iron to remediate sites with non-aqueous phase or significant sediment-associated contaminant mass can be limited by relatively low rates of mass transfer to bring contaminants in contact with the reactive media. For a field test in a trichloroethene source area, combining moderate-temperature (maximum 50oC) subsurface electrical resistance heating with in situ ZVI treatment was shown to accelerate dechlorination and dissolution rates by a factor of 4 to 6 based on organic daughter products and a factor 8-16 using a chloride concentrations. A mass-discharge-based analysis was used to evaluate reaction, dissolution, and volatilization at ambient groundwater temperature (~10oC) and as temperature was increased up to about 50oC. Increased reaction and contaminant dissolution were observed with increased temperature, but volatilization was minimal during the test because in situ reactions maintained low aqueous-phase TCE concentrations.

  20. Verification of combined thermal-hydraulic and heat conduction analysis code FLOWNET/TRUMP

    Science.gov (United States)

    Maruyama, Soh; Fujimoto, Nozomu; Kiso, Yoshihiro; Murakami, Tomoyuki; Sudo, Yukio

    1988-09-01

    This report presents the verification results of the combined thermal-hydraulic and heat conduction analysis code, FLOWNET/TRUMP which has been utilized for the core thermal hydraulic design, especially for the analysis of flow distribution among fuel block coolant channels, the determination of thermal boundary conditions for fuel block stress analysis and the estimation of fuel temperature in the case of fuel block coolant channel blockage accident in the design of the High Temperature Engineering Test Reactor(HTTR), which the Japan Atomic Energy Research Institute has been planning to construct in order to establish basic technologies for future advanced very high temperature gas-cooled reactors and to be served as an irradiation test reactor for promotion of innovative high temperature new frontier technologies. The verification of the code was done through the comparison between the analytical results and experimental results of the Helium Engineering Demonstration Loop Multi-channel Test Section(HENDEL T(sub 1-M)) with simulated fuel rods and fuel blocks.

  1. Combined effect of heat treatment and humidity on total polyphenol content of tartary buckwheat wholeflour

    Directory of Open Access Journals (Sweden)

    Andrea BRUNORI

    2016-12-01

    Full Text Available Minor crops are gaining new interest due to the high content of bioactive compounds available in their grain and the consequent opportunity to be employed as ingredients for the production of healthy foodstuff. Tartary buckwheat (Fagopyrum tataricum Gaertn. grain is rich in flavonoids, the most important being represented by rutin, a compound possessing a high health value. When processing bakery products added with Tartary buckwheat whole flour, the key point is to prevent rutin from being hydrolysed to quercetin. In this view, a combination of heat treatment and controlled humidity level was applied for different lengths of time, in the attempt to deactivate the enzymes catalysing the reaction. Tartary buckwheat grain contains other polyphenols also capable to confer health properties. This class of compounds has been associated with the prevention of cardiovascular diseases, cancers, neurodegenerative diseases, diabetes, and osteoporosis. In this study it was observed how the physical treatments meant to preserve rutin would influence the overall content of polyphenols in Tartary buckwheat whole flour and dough.

  2. A systematic outline of the system combination of solar thermal power plants and heat pumps; Systematische Gliederung der Systemkombination von solarthermischen Anlagen und Waermepumpen

    Energy Technology Data Exchange (ETDEWEB)

    Haller, Michel Y.; Frank, Elimar [Hochschule fuer Technik HSR, Rapperswil (Switzerland). SPF Inst. fuer Solartechnik; Trinkl, Christoph; Zoerner, Wilfried [Hochschule Ingolstadt (Germany). Kompetenzfeld Erneuerbare Energien

    2010-07-01

    In recent years, increasingly systems for heat supply for space heating and hot water were developed based on the combination of solar thermal systems and heat pumps up to serial production. The manufacturers or suppliers either come from the solar energy industry or from the heat pump sector and accordingly have the specific background knowledge in one of these two technologies. Thus, two different approaches for the conceptual design of system solutions are identifiable. Under this aspect, the authors of the contribution under consideration report on the actual classification in solar thermal systems and heat pumps as well as a systematic outline concept for combined solar heat pump systems.

  3. An experimental investigation of heat transfer enhancement in minichannel: Combination of nanofluid and micro fin structure techniques

    DEFF Research Database (Denmark)

    Zhang, Ji; Diao, Yanhua; Zhao, Yaohua;

    2017-01-01

    This work experimentally studied the single-phase heat transfer and pressure drop characteristics by using two heat transfer enhancement techniques (micro fin structure and nanofluids) in multiport minichannel flat tube (MMFT). MMFT consisted of numerous parallel rectangular minichannels and is w......This work experimentally studied the single-phase heat transfer and pressure drop characteristics by using two heat transfer enhancement techniques (micro fin structure and nanofluids) in multiport minichannel flat tube (MMFT). MMFT consisted of numerous parallel rectangular minichannels...... with different micro fin numbers (N = 0, 1, 2, 3 and 4) and nanofluids with three volume concentrations (φ = 0.005%, 0.01% and 0.1%) were used as test sections and working fluids respectively. Secondly, the experiments using two combined enhancement technique were performed. By using conjunctively two...

  4. Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment.

    Science.gov (United States)

    Wang, Qilin; Jiang, Guangming; Ye, Liu; Yuan, Zhiguo

    2014-10-15

    Methane production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow degradation and poor substrate availability of WAS. Our previous study revealed that WAS pre-treatment using free nitrous acid (FNA, i.e. HNO2) is an economically feasible and environmentally friendly method for promoting methane production. In order to further improve methane production from WAS, this study presents a novel strategy based on combined FNA and heat pre-treatment. WAS from a full-scale plant was treated for 24 h with FNA alone (0.52-1.43 mg N/L at 25 °C), heat alone (35, 55 and 70 °C), and FNA (0.52-1.11 mg N/L) combined with heat (35, 55 and 70 °C). The pre-treated WAS was then used for biochemical methane potential tests. Compared to the control (no FNA or heat pre-treatment of WAS), biochemical methane potential of the pre-treated WAS was increased by 12-16%, 0-6%, 17-26%, respectively; hydrolysis rate was improved by 15-25%, 10-25%, 20-25%, respectively, for the three types of pre-treatment. Heat pre-treatment at 55 and 70 °C, independent of the presence or absence of FNA, achieved approximately 4.5 log inactivation of pathogens (in comparison to ∼1 log inactivation with FNA treatment alone), thus capable of producing Class A biosolids. The combined FNA and heat pre-treatment is an economically and environmentally attractive technology for the pre-treatment of WAS prior to anaerobic digestion, particularly considering that both FNA and heat can be produced as by-products of anaerobic sludge digestion.

  5. Temperature sensitive liposomes combined with thermal ablation: Effects of duration and timing of heating in mathematical models and in vivo.

    Science.gov (United States)

    Rossmann, Christian; McCrackin, M A; Armeson, Kent E; Haemmerich, Dieter

    2017-01-01

    Temperature sensitive liposomes (TSL) are nanoparticles that rapidly release the contained drug at hyperthermic temperatures, typically above ~40°C. TSL have been combined with various heating modalities, but there is no consensus on required hyperthermia duration or ideal timing of heating relative to TSL administration. The goal of this study was to determine changes in drug uptake when heating duration and timing are varied when combining TSL with radiofrequency ablation (RF) heating. We used computer models to simulate both RF tissue heating and TSL drug delivery, to calculate spatial drug concentration maps. We simulated heating for 5, 12 and 30 min for a single RF electrode, as well as three sequential 12 min ablations for 3 electrodes placed in a triangular array. To support simulation results, we performed porcine in vivo studies in normal liver, where TSL filled with doxorubicin (TSL-Dox) at a dose of 30 mg was infused over 30 min. Following infusion, RF heating was performed in separate liver locations for either 5 min (n = 2) or 12 min (n = 2). After ablation, the animal was euthanized, and liver extracted and frozen. Liver samples were cut orthogonal to the electrode axis, and fluorescence imaging was used to visualize tissue doxorubicin distribution. Both in vivo studies and computer models demonstrate a ring-shaped drug deposition within ~1 cm of the visibly coagulated tissue. Drug uptake directly correlated with heating duration. In computer simulations, drug concentration increased by a factor of 2.2x and 4.3x when heating duration was extended from 5 to either 12, or 30 minutes, respectively. In vivo, drug concentration was by a factor of 2.4x higher at 12 vs 5 min heating duration (7.1 μg/g to 3.0 μg/g). The computer models suggest that heating should be timed to maximize area under the curve of systemic plasma concentration of encapsulated drug. Both computer models and in vivo study demonstrate that tissue drug uptake directly correlates with

  6. Determination of Fuel Consumption Indexes of Co-generation Combined Cycle Steam and Gas Units with unfired waste heat boilers

    Directory of Open Access Journals (Sweden)

    S. A. Kachan

    2010-01-01

    Full Text Available The paper presents the developed methodology and the results of determination of fuel consumption indexes of co-generation combined cycle steam and gas units (PGU with unfired waste heat boilers apply to PGU-230 of 3-d co-generation power plant ofMinsk. 

  7. Support schemes and ownership structures - the policy context for fuel cell based micro-combined heat and power

    DEFF Research Database (Denmark)

    Schröder, Sascha Thorsten; Costa, Ana; Obé, Elisabeth

    2011-01-01

    In recent years, fuel cell based micro-combined heat and power (mCHP) has received increasing attention due to its potential contribution to European energy policy goals, i.e., sustainability, competitiveness and security of supply. Besides technical advances, regulatory framework and ownership s...

  8. 1?10 kW Stationary Combined Heat and Power Systems Status and Technical Potential: Independent Review

    Energy Technology Data Exchange (ETDEWEB)

    Maru, H. C.; Singhal, S. C.; Stone, C.; Wheeler, D.

    2010-11-01

    This independent review examines the status and technical potential of 1-10 kW stationary combined heat and power fuel cell systems and analyzes the achievability of the DOE cost, efficiency, and durability targets for 2012, 2015, and 2020.

  9. 1?10 kW Stationary Combined Heat and Power Systems Status and Technical Potential: Independent Review

    Energy Technology Data Exchange (ETDEWEB)

    Maru, H. C.; Singhal, S. C.; Stone, C.; Wheeler, D.

    2010-11-01

    This independent review examines the status and technical potential of 1-10 kW stationary combined heat and power fuel cell systems and analyzes the achievability of the DOE cost, efficiency, and durability targets for 2012, 2015, and 2020.

  10. Initial Development of a Combined PCM and TABS Solution for Heat Storage and Cooling

    DEFF Research Database (Denmark)

    Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

    2011-01-01

    This paper investigates heat storage and cooling concept that utilizes both phase change material (PCM) and a thermal active building system (TABS) implemented in a hollow core concrete deck element. PCMs are promising materials for improving the heat storage capacity of a building due...... to their significant thermal energy storage capabilities. The TABS has a potential for increasing the exploitation of the thermal mass of the building, which is rarely exposed for heat transfer.The main objective of this study is to optimize the location and amount of PCM in a hollow core deck in order to optimize...... heat storage capacity. A series of simulations were conducted using the COMSOL program to obtain knowledge regarding the dynamic heat storage capacity of the investigated hollow core deck element as a function of the amount and location of PCM. Furthermore, the dynamic heat storage capacity...

  11. Improving flexibility characteristics of 200 MW unit

    Directory of Open Access Journals (Sweden)

    Taler Jan

    2017-03-01

    Full Text Available Calculations were performed of the thermal system of a power plant with installed water pressure tanks. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters is determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the off-peak night hours, water heated in low-pressure regenerative heaters and feed water tank to the nominal temperature is directed to water pressure tanks. The water accumulated during the night is used to feed the boiler during the period of peak demand for electricity. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. A financial and economic profitability analysis (of costs and benefits is made of the use of tanks for a 200 MW power unit. Operating in the automatic system of frequency and power control, the tanks may also be used to ensure a sudden increase in the electric power of the unit. The results of the performed calculations and analyses indicate that installation of water pressure tanks is well justified. The investment is profitable. Water pressure tanks may not only be used to reduce the power unit power during the off-peak night hours and raise it in the periods of peak demand, but also to increase the power capacity fast at any time. They may also be used to fill the boiler evaporator with hot water during the power unit start-up from the cold state.

  12. Improving flexibility characteristics of 200 MW unit

    Science.gov (United States)

    Taler, Jan; Trojan, Marcin; Taler, Dawid; Dzierwa, Piotr; Kaczmarski, Karol

    2017-03-01

    Calculations were performed of the thermal system of a power plant with installed water pressure tanks. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters is determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the off-peak night hours, water heated in low-pressure regenerative heaters and feed water tank to the nominal temperature is directed to water pressure tanks. The water accumulated during the night is used to feed the boiler during the period of peak demand for electricity. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. A financial and economic profitability analysis (of costs and benefits) is made of the use of tanks for a 200 MW power unit. Operating in the automatic system of frequency and power control, the tanks may also be used to ensure a sudden increase in the electric power of the unit. The results of the performed calculations and analyses indicate that installation of water pressure tanks is well justified. The investment is profitable. Water pressure tanks may not only be used to reduce the power unit power during the off-peak night hours and raise it in the periods of peak demand, but also to increase the power capacity fast at any time. They may also be used to fill the boiler evaporator with hot water during the power unit start-up from the cold state.

  13. 1000 MW ultra-supercritical turbine steam parameter optimization

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The 2 ×1000 MW ultra-supercritical steam turbine of Shanghai Waigaoqiao Phase Ⅲ project,which uses grid frequency regulation and overload control through an overload valve,is manufactured by Shanghai Turbine Company using Siemens technology.Through optimization,the steam pressure is regarded as the criterion between constant pressure and sliding pressure operation.At high circulating water temperature,the turbine overload valve is kept closed when the unit load is lower than 1000 MW while at other circulating water temperatures the turbine can run in sliding pressure operation when the unit load is higher than 1000 MW and the pressure is lower than 27 MPa This increases the unit operation efficiency.The 3D bending technology in the critical piping helps to reduce the project investment and minimize the reheat system pressure drop which improves the unit operation efficiency and safety.By choosing lower circulating water design temperature and by setting the individual Boiler Feedwater Turbine condenser to reduce the exhaust steam flow and the heat load to the main condenser,the unit average back pressure and the terminal temperature difference are minimized.Therefore,the unit heat efficiency is increased.

  14. Optimization of a thermal storage unit combined with a biomass bioler for heating buildings

    OpenAIRE

    Butala, Vincenc; Stritih, Uroš

    2015-01-01

    The performance of a boiler with a built-in thermal storage unit is presented.The thermal storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the thermal storage unit makes it possible to heat even when the boiler is not operating, thus increasing the heating efficiency. A system with three components is described. The model of the system and the mathematical model were made using the TRNSYS program package and a test reference year (TRY). The...

  15. Critical factors for profitable combined production of heat, power and biofuels; Kritiska faktorer foer loensam produktion i bioenergikombinat

    Energy Technology Data Exchange (ETDEWEB)

    Nohlgren, Ingrid; Gunnarsson, Emma; Lundqvist, Per; Stigander, Haakan; Widmark, Annika (AaF, Stockholm (Sweden))

    2012-02-15

    During the last 5-10 years, research and development efforts have been made in the field of polygeneration of heat and power with production of 'other green' products such as transport fuels or wood pellets. The driving force for heat and power producers is the potential of increased profitability through additional sales of heat. The driving force for wood pellet and some transport fuel producers is the potential of low cost process steam or heat. However, in the case of gasification based transport fuel production processes the situation is different. The process generates a surplus of heat, which can benefit from the proximity of a district heating net. In addition, some polygeneration combinations could provide other advantages such as more efficient raw material handling. Together with these driving forces, the EU renewable energy directive (which targets 10 % renewable energy use in the transport sector by 2020), shows that the market for production of renewable transport fuel is expanding. To refine Swedish biomass resources to more highly valuable products such as wood pellets or renewable transport fuels would maintain industry and employment opportunities within Sweden and at the same time fulfils the international and national climate targets. The overall aim with this project is to describe the factors which are crucial for the opportunity for profitable polygeneration of heat, power and wood pellets or renewable transport fuels and how these factors influence the location of such a plant within Sweden. The important factors can be categorized as: (1) Supply of raw material, (2) distribution of raw material and products, (3) Demand of products and (4) Integration between the different plants. In this project, only general aspects are described and should be seen as guidance for the industry (both energy and forest industry) which has an interest in polygeneration. The project gives an overview of different possibilities, opportunities and

  16. Business Case for a Micro-Combined Heat and Power Fuel Cell System in Commercial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P.; Makhmalbaf, Atefe; Anderson, David M.; Amaya, Jodi P.; Pilli, Siva Prasad; Srivastava, Viraj; Upton, Jaki F.

    2013-10-30

    Combined heat and power fuel cell systems (CHP-FCSs) provide consistent electrical power and hot water with greater efficiency and lower emissions than alternative sources. These systems can be used either as baseload, grid-connected, or as off-the-grid power sources. This report presents a business case for CHP-FCSs in the range of 5 to 50 kWe. Systems in this power range are considered micro-CHP-FCS. For this particular business case, commercial applications rather than residential or industrial are targeted. To understand the benefits of implementing a micro-CHP-FCS, the characteristics that determine their competitive advantage must first be identified. Locations with high electricity prices and low natural gas prices are ideal locations for micro-CHP-FCSs. Fortunately, these high spark spread locations are generally in the northeastern area of the United States and California where government incentives are already in place to offset the current high cost of the micro-CHP-FCSs. As a result of the inherently high efficiency of a fuel cell and their ability to use the waste heat that is generated as a CHP, they have higher efficiency. This results in lower fuel costs than comparable alternative small-scale power systems (e.g., microturbines and reciprocating engines). A variety of markets should consider micro-CHP-FCSs including those that require both heat and baseload electricity throughout the year. In addition, the reliable power of micro-CHP-FCSs could be beneficial to markets where electrical outages are especially frequent or costly. Greenhouse gas emission levels from micro-CHP-FCSs are 69 percent lower, and the human health costs are 99.9 percent lower, than those attributed to conventional coal-fired power plants. As a result, FCSs can allow a company to advertise as environmentally conscious and provide a bottom-line sales advantage. As a new technology in the early stages of adoption, micro-CHP-FCSs are currently more expensive than alternative

  17. Numerical Simulation Study on IP Rotor Coding Coupled Heat Transfer of 1000MW Ultra-supercritical Steam Turbine%1000MW超超临界汽轮机中压转子冷却耦合换热数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    杨明; 李长宝; 管继伟; 刘云峰

    2013-01-01

    By using CFD and conjugate heat transfer(CHT) methods,IP Rotor Cooling of 1000MW Ultra-supercritical Steam Turbine has been numerical simulated.The temperature distribution whether the fluid and solid coupled heat transfer,cooling steam temperature effects on IP Rotor and the temperature distribution of the two half-rotor have been investigated.The fluid and solid temperature field distribution characteristics has been more realistic simulated.This article can provide a reliable basis for the structural design of ultra-supercritical steam turbine.%通过采用CFD和CHT(共轭换热)的数值方法,对超超临界1000MW汽轮机中压转子冷却进行了数值模拟,研究了有无流体与固体耦合换热的温度场分布差别,冷却蒸汽温度对中压转子冷却效果的影响,中压二级半转子冷却的温度分布,较真实地模拟了流体、固体区域温度场的分布特性.

  18. Parametric Investigation and Thermoeconomic Optimization of a Combined Cycle for Recovering the Waste Heat from Nuclear Closed Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Lihuang Luo

    2016-01-01

    Full Text Available A combined cycle that combines AWM cycle with a nuclear closed Brayton cycle is proposed to recover the waste heat rejected from the precooler of a nuclear closed Brayton cycle in this paper. The detailed thermodynamic and economic analyses are carried out for the combined cycle. The effects of several important parameters, such as the absorber pressure, the turbine inlet pressure, the turbine inlet temperature, the ammonia mass fraction, and the ambient temperature, are investigated. The combined cycle performance is also optimized based on a multiobjective function. Compared with the closed Brayton cycle, the optimized power output and overall efficiency of the combined cycle are higher by 2.41% and 2.43%, respectively. The optimized LEC of the combined cycle is 0.73% lower than that of the closed Brayton cycle.

  19. Combined heat treatment and acid hydrolysis of cassava grate waste (CGW) biomass for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Agu, R.C.; Amadife, A.E.; Ude, C.M.; Onyia, A.; Ogu, E.O. [Enugu State Univ. of Science and Technology (Nigeria). Faculty of Applied Natural Sciences; Okafor, M.; Ezejiofor, E. [Nnamdi Azikiwe Univ., Awka (Nigeria). Dept. of Applied Microbiology

    1997-12-31

    The effect of combined heat treatment and acid hydrolysis (various concentrations) on cassava grate waste (CGW) biomass for ethanol production was investigated. At high concentrations of H{sub 2}SO{sub 4} (1--5 M), hydrolysis of the CGW biomass was achieved but with excessive charring or dehydration reaction. At lower acid concentrations, hydrolysis of CGW biomass was also achieved with 0.3--0.5 M H{sub 2}SO{sub 4}, while partial hydrolysis was obtained below 0.3 M H{sub 2}SO{sub 4} (the lowest acid concentration that hydrolyzed CGW biomass) at 120 C and 1 atm pressure for 30 min. A 60% process efficiency was achieved with 0.3 M H{sub 2}SO{sub 4} in hydrolyzing the cellulose and lignin materials present in the CGW biomass. High acid concentration is therefore not required for CGW biomass hydrolysis. The low acid concentration required for CGW biomass hydrolysis, as well as the minimal cost required for detoxification of CGW biomass because of low hydrogen cyanide content of CGW biomass would seem to make this process very economical. From three liters of the CGW biomass hydrolysate obtained from hydrolysis with 0.3M H{sub 2}SO{sub 4}, ethanol yield was 3.5 (v/v%) after yeast fermentation. However, although the process resulted in gainful utilization of CGW biomass, additional costs would be required to effectively dispose new by-products generated from CGW biomass processing.

  20. Effects of combined heat and ionizing radiation on thiamine (vitamin B 1) content in model systems and food matrices

    Science.gov (United States)

    Chuaqui-Offermanns, N.; Shoemaker, L.; McDougall, T.

    The effects of heat and radiation on thiamine stability are being studied both singly and in combination. Heat, γ-radiation and a combination of them were applied to a model system consisting of 2 × 10 -5 M thiamine hydrochloride in 0.01N HC1 (pH=2.5), and their effects are reported. The effects of these two agents on thiamine in two food matrices, concentrated orange juice and green peas, are also reported. Heat was not found to have a significant effect on thiamine in the model system at temperatures up to 120°C for up to 60 min of treatment. A small, but significant heat effect was found in the two foods. The retention of thiamine in the model system and in the two foods decreased exponentially as the radiation dose increased. The degradation of thiamine by γ-radiation in both foods was a factor of 10 less than that observed in the model system. A small, but significant synergistic effect was found when samples of the model system were heated at 120°C for one hour 24 h after irradiation.

  1. Study on the Optimizing Operation of Exhaust Air Heat Recovery and Solar Energy Combined Thermal Compensation System for Ground-Coupled Heat Pump

    Directory of Open Access Journals (Sweden)

    Kuan Wang

    2017-01-01

    Full Text Available This study proposed an exhaust air heat recovery and solar energy combined thermal compensation system (ESTC for ground-coupled heat pumps. Based on the prediction of the next day’s exhaust air temperature and solar irradiance, an optimized thermal compensation (OTC method was developed in this study as well, in which the exhaust air heat recovery compensator and solar energy compensator in the ESTC system run at high efficiency throughout various times of day. Moreover, a modified solar term similar days group (STSDG method was proposed to improve the accuracy of solar irradiance prediction in hazy weather. This modified STSDG method was based on air quality forecast and AQI (air quality index correction factors. Through analyzing the operating parameters and the simulation results of a case study, the ESTC system proved to have good performance and high efficiency in eliminating the heat imbalance by using the OTC method. The thermal compensation quantity per unit energy consumption (TEC of ESTC under the proposed method was 1.25 times as high as that under the traditional operation method. The modified STSDG method also exhibited high accuracy. For the accumulated solar irradiance of the four highest daily radiation hours, the monthly mean absolute percentage error (MAPE between the predicted values and the measured values was 6.35%.

  2. Enhancement of the immune response against Salmonella infection of mice by heat-killed multispecies combinations of lactic acid bacteria.

    Science.gov (United States)

    Chen, Chih-Yuan; Tsen, Hau-Yang; Lin, Chun-Li; Lin, Chien-Ku; Chuang, Li-Tsen; Chen, Chin-Shuh; Chiang, Yu-Cheng

    2013-11-01

    Heat-killed lactic acid bacteria (LAB) has advantages over live LAB in that it has a long shelf-life and is therefore easy to store and transport. From four LAB strains selected by immunomodulatory activity and adherent properties, we prepared the heat-killed multispecies combination of LAB (MLAB) and the cell walls from MLAB under two conditions (100 °C for 30 min and 121 °C for 15 min). Different effects on the adherent properties of these four LAB strains were observed, depending on the heating conditions. With mouse macrophage cells, the two heat-killed MLABs (HMLABs) showed significantly higher induction activities on the production of interleukin 12 (IL-12) than their individual strains did. Heat-killed MLABs and cell-wall preparations were able to reduce the Salmonella invasion of Caco-2 and mouse macrophage cells. Feeding mice with HMLAB could inhibit the Salmonella invasion of mice significantly. For these mice, the expression level of pro-inflammatory cytokines, such as TNF-α and IL-6, in mouse serum was reduced while that of the anti-inflammatory cytokine, i.e. IL-10, was enhanced. The HMLABs developed in this study showed higher protective effect against Salmonella invasion either of Caco-2 cells or of mice, relative to the heat-killed lactobacilli, which consisted of Lactobacillus acidophilus strains selected at random. In conclusion, the HMLABs were potentially useful for the protection of mice against Salmonella infection and the induced inflammation.

  3. Effect of Chinese Herbal Medicine Combined with Acitretin Capsule in Treating Psoriasis of Blood-Heat Syndrome Type

    Institute of Scientific and Technical Information of China (English)

    张立新; 白彦萍; 宋佩华; 尤立平; 杨顶权

    2009-01-01

    Objective:To observe the clinical curative effect of Chinese herbal medicine combined with acitretin capsule in treating psoriasis of blood-heat syndrome(P-BH).Methods:Eighty patients of P-BH were randomly assigned to two groups,39 in Group A and 41 in Group B.Both was treated with Chinese herbal medicines for clearing heat,cooling blood and removing toxic substance,and acitretin capsule was given to Group A additionally,with 8 weeks as one therapeutic course.The clinical curative effect was compared bet...

  4. Optimal Design of Cogeneration Systems in Industrial Plants Combined with District Heating/Cooling and Underground Thermal Energy Storage

    Directory of Open Access Journals (Sweden)

    Vincenzo Dovì

    2011-12-01

    Full Text Available Combined heat and power (CHP systems in both power stations and large plants are becoming one of the most important tools for reducing energy requirements and consequently the overall carbon footprint of fundamental industrial activities. While power stations employ topping cycles where the heat rejected from the cycle is supplied to domestic and industrial consumers, the plants that produce surplus heat can utilise bottoming cycles to generate electrical power. Traditionally the waste heat available at high temperatures was used to generate electrical power, whereas energy at lower temperatures was either released to the environment or used for commercial or domestic heating. However the introduction of new engines, such as the ones using the organic Rankine cycle, capable of employing condensing temperatures very close to the ambient temperature, has made the generation of electrical power at low temperatures also convenient. On the other hand, district heating is becoming more and more significant since it has been extended to include cooling in the warm months and underground storage of thermal energy to cope with variable demand. These developments imply that electric power generation and district heating/cooling may become alternative and not complementary solutions for waste energy of industrial plants. Therefore the overall energy management requires the introduction of an optimisation algorithm to select the best strategy. In this paper we propose an algorithm for the minimisation of a suitable cost function, for any given variable heat demand from commercial and domestic users, with respect to all independent variables, i.e., temperatures and flowrates of warm fluid streams leaving the plants and volume and nature of underground storage. The results of the preliminary process integration analysis based on pinch technology are used in this algorithm to provide bounds on the values of temperatures.

  5. Influence of dimethyl dicarbonate on the resistance of Escherichia coli to a combined UV-Heat treatment in apple juice

    Science.gov (United States)

    Gouma, Maria; Gayán, Elisa; Raso, Javier; Condón, Santiago; Álvarez, Ignacio

    2015-01-01

    Commercial apple juice inoculated with Escherichia coli was treated with UV-C, heat (55°C) and dimethyl dicarbonate – DMDC (25, 50, and 75 mg/L)-, applied separately and in combination, in order to investigate the possibility of synergistic lethal effects. The inactivation levels resulting from each treatment applied individually for a maximum treatment time of 3.58 min were limited, reaching 1.2, 2.9, and 0.06 log10 reductions for UV, heat, and DMDC (75 mg/L), respectively. However, all the investigated combinations resulted in a synergistic lethal effect, reducing the total treatment time and UV dose, with the synergistic lethal effect being higher when larger concentrations of DMDC were added to the apple juice. The addition of 75 mg/L of DMDC prior to the combined UV-C light treatment at 55°C resulted in 5 log10 reductions after only 1.8 min, reducing the treatment time and UV dose of the combined UV-Heat treatment by 44%. PMID:26042117

  6. Combined effect of pH and heating conditions on the physical properties of Alaska pollock surimi gels.

    Science.gov (United States)

    Lee, Myeong Gi; Yoon, Won Byong; Park, Jae W

    2017-06-01

    Physical properties of Alaska pollock surimi paste were investigated as affected by pH (4.0 and 6.0-10.0) and heating conditions (slow and fast). The highest values of gel strength and deformability, as shown by breaking force and penetration distance, were obtained at pH 7.5-8.0, while the lowest values were at pH 10.0 followed by pH 6.0 and pH 6.5, respectively. Two-step slow heating process increased the breaking strength value nearly two times higher than one-step fast heating. The effect of pH was strikingly high at pH 7.5 when gels were prepared using 2-step heating, indicating the pH dependence of endogenous transglutaminase. However, the highest gel strength was obtained at pH 8.0 when gels were prepared in fast heating. Whiteness value (L - 3b*) increased significantly (p heated gels showed the lowest yellowness, resulting in whiter appearance, probably due to the effect of reduced browning reaction. The uniqueness of this study was to measure the combined effect of pH and heating conditions on the gel texture and color. There were various studies dealing with pH or heating conditions independently. As the primary character for surimi seafood is gel texture and color. The highest values of gel strength and deformability, as shown by breaking force and penetration distance, were obtained at pH 7.5-8.0, while the lowest values were at pH 10.0 followed by pH 6.0 and pH 6.5, respectively. Two-step slow heating process increased the breaking strength value nearly two times higher than one-step fast heating. Whiteness value (L - 3b*) increased significantly as pH increased from 6.0 to 6.5, but thereafter decreased significantly as pH increased. L* value (lightness) and b* value (yellowness) continuously decreased as the pH is shifted from 6.0 to 10. Fast heated gels showed the lowest yellowness, resulting in whiter appearance. © 2016 Wiley Periodicals, Inc.

  7. The Optimized Operation of Gas Turbine Combined Heat and Power Units Oriented for the Grid-Connected Control

    Science.gov (United States)

    Xia, Shu; Ge, Xiaolin

    2016-04-01

    In this study, according to various grid-connected demands, the optimization scheduling models of Combined Heat and Power (CHP) units are established with three scheduling modes, which are tracking the total generation scheduling mode, tracking steady output scheduling mode and tracking peaking curve scheduling mode. In order to reduce the solution difficulty, based on the principles of modern algebraic integers, linearizing techniques are developed to handle complex nonlinear constrains of the variable conditions, and the optimized operation problem of CHP units is converted into a mixed-integer linear programming problem. Finally, with specific examples, the 96 points day ahead, heat and power supply plans of the systems are optimized. The results show that, the proposed models and methods can develop appropriate coordination heat and power optimization programs according to different grid-connected control.

  8. Distributed Optimal Economic Dispatch Based on Multi-Agent System Framework in Combined Heat and Power Systems

    Directory of Open Access Journals (Sweden)

    Yu-Shuai Li

    2016-10-01

    Full Text Available In this paper, a novel distributed method is presented to solve combined heat and power economic dispatch problem, which is formulated as a distributed coupled optimization problem. The optimization goal is achieved by establishing two modified consensus protocols with two corresponding feedback parts while satisfying the electrical and heat supply–demand balance. Moreover, an alternating iterative method is proposed to handle the heat-electrical coupling problem existed in the objective function and the feasible operating regions. In addition, the proposed distributed method is implemented by a multi-agent system framework, which only requires local information exchange among neighboring agents. Simulation results obtained on a 16-bus test system are provided to illustrate the effectiveness of the proposed distributed method.

  9. A Novel Approach for Cooling Electronics Using a Combined Heat Pipe and Thermoelectric Module

    OpenAIRE

    Banjerd Saengchandr; Nitin V. Afzulpurkar

    2009-01-01

    The development of effective cooling systems for microprocessors, specifically for CPU and other computer chips, is greatly important due to growth of high speed performance chips, which operate at elevated heat rates. The same issues apply for adjacent units including RAM and HDD also contributing to overall generation of heat inside computer. Problem statement: Conventional cooling system for desktop PC has many problems, especially cooling performance. Lifespan of devices and reliable oper...

  10. Design of serially connected district heating heat pumps utilising a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    The design of two heat pumps (HP), connected in series, was investigated for operation in the district heating (DH) network of the Greater Copenhagen area, Denmark. The installation was dimensioned to supply 7.2 MW of heat at a temperature of 85 °C. The heat pumps utilise a geothermal heat source...

  11. Drag and heat reduction mechanism induced by a combinational novel cavity and counterflowing jet concept in hypersonic flows

    Science.gov (United States)

    Sun, Xi-wan; Guo, Zhen-yun; Huang, Wei; Li, Shi-bin; Yan, Li

    2016-09-01

    The drag and heat reduction problem of hypersonic reentry vehicles has always attracted the attention worldwide, and many novel schemes have been proposed recently. In the current study, the research progress of the combinational configuration of the forward-facing cavity and the counterflowing jet has been reviewed, and the conventional cavity configuration has been substituted by an approximate maximum thrust nozzle contour for better heat and surface pressure reduction efficiency. The Reynolds-average of Navier-Stokes (RANS) equations coupled with the SST k-ω turbulence model have been employed to calculate its surrounding flow fields. A validation metric and the grid convergence index (GCI) have been employed to conduct the turbulence model assessment and the grid independence analysis respectively. The axisymmetric assumption has been verified by three-dimensional computational results as well. The obtained results show that the SST k-ω model is more suitable for the novel drag and heat flux reduction scheme proposed in this article, and the axisymmetric assumption is approximately reasonable. After investigating the influence of jet pressure ratio, the novel combinational configuration has been verified to be more effective in heat and surface pressure reduction, and this is because the approximate maximum thrust nozzle contour contributes to better expansion and avoids total pressure loss of the jet.

  12. PERFORMANCE EVALUATION OF BOILERS (80 AND 40 TPH AND 21MW STEAM TURBINE OF COGEN PLANT

    Directory of Open Access Journals (Sweden)

    D.P.TAWARE

    2014-06-01

    Full Text Available The proposed study is conducted at The Malegaon Sugar Mills, Baramati, and District Pune. Data is collected for a high pressure 80 TPH & 40TPH bagasse fired boiler. The boilers are natural circulation and bi-drum water tube type. The both boilers are equipped with super heater, air heater and economizer in order to utilize maximum available heat of flue gases. Boiler efficiency is calculated by indirect method. Also plant has 21 MW cogeneration capacity, with two turbines are installed with capacity 14MW (Back Pressure Type & 7MW (Extraction Cum Condensing Type. From the heat input given to turbines per unit of electricity generated, the turbine heat rate is calculated. Different instruments and devices are used to record the different parameters of both boilers & turbines. Steam produced per ton of bagasse is being found out for both boilers.

  13. A comparative property investigation of lithium phosphate glass melted in microwave and conventional heating

    Indian Academy of Sciences (India)

    AVIK HALDER; BISWAJIT MANDAL; SOURINDRA MAHANTY; RANJAN SEN; ASHIS KUMAR MANDAL

    2017-09-01

    The present study addresses the application of microwave (MW) energy for melting lithium phosphate glass. Acomparative analysis of the properties is presented with glasses melted in conventional resistance heating adopting standardmethods of characterization. The density of the glass was found less in MW heating. The glass transition temperature wasrecorded as 3–10$^{\\circ}$C lower in MW prepared glass than in conventional glass.Micro-hardness is found to be improved in caseof MW heating. Maximum forward power was recorded less than 2 kW with an average power $\\sim$1 kW during melting of40 g glass in MW furnace. MW forward and reflected power measured during melting in the MW cavity was elaborated.Total melting time was within 2 h 30 min in MW heating, whereas it was 6–7 h in resistive heating. Total power consumedwas $\\sim$5 kWh in MW heating and $\\sim$14 kWh in resistance heating.

  14. Combined Heat and Power: Effective Energy Solutions for a Sustainable Future

    Energy Technology Data Exchange (ETDEWEB)

    Shipley, Ms. Anna [Sentech, Inc.; Hampson, Anne [Energy and Environmental Analysis, Inc., an ICF Company; Hedman, Mr. Bruce [Energy and Environmental Analysis, Inc., an ICF Company; Garland, Patricia W [ORNL; Bautista, Paul [Sentech, Inc.

    2008-12-01

    Combined Heat and Power (CHP) solutions represent a proven and effective near-term energy option to help the United States enhance energy efficiency, ensure environmental quality, promote economic growth, and foster a robust energy infrastructure. Using CHP today, the United States already avoids more than 1.9 Quadrillion British thermal units (Quads) of fuel consumption and 248 million metric tons of carbon dioxide (CO{sub 2}) emissions annually compared to traditional separate production of electricity and thermal energy. This CO{sub 2} reduction is the equivalent of removing more than 45 million cars from the road. In addition, CHP is one of the few options in the portfolio of energy alternatives that combines environmental effectiveness with economic viability and improved competitiveness. This report describes in detail the four key areas where CHP has proven its effectiveness and holds promise for the future as an: (1) Environmental Solution: Significantly reducing CO{sub 2} emissions through greater energy efficiency; (2) Competitive Business Solution: Increasing efficiency, reducing business costs, and creating green-collar jobs; (3) Local Energy Solution: Deployable throughout the US; and (4) Infrastructure Modernization Solution: Relieving grid congestion and improving energy security. CHP should be one of the first technologies deployed for near-term carbon reductions. The cost-effectiveness and near-term viability of widespread CHP deployment place the technology at the forefront of practical alternative energy solutions such as wind, solar, clean coal, biofuels, and nuclear power. Clear synergies exist between CHP and most other technologies that dominate the energy and environmental policy dialogue in the country today. As the Nation transforms how it produces, transports, and uses the many forms of energy, it must seize the clear opportunity afforded by CHP in terms of climate change, economic competitiveness, energy security, and infrastructure

  15. Effects of combination of magnesium and zinc oxide nanoparticles and heat on Escherichia coli and Staphylococcus aureus bacteria in milk

    Directory of Open Access Journals (Sweden)

    M. Kimiaee Sadr

    2016-01-01

    Full Text Available Objective: The objective of this study was to investigate the antibacterial activities of combination of MgO and ZnO nanoparticles in the presence of heat against Escherichia coli and Staphylococcus aureus. Materials and Methods:Bacteria were grown on either agar or broth media followed by the addition of ZnO and MgO nanoparticles. Then the combined effect of ZnO and MgO nanoparticles was investigated.  Furthermore, the media containing nanoparticles were treated with mild heat and their synergistic antibacterial activity was investigated against E. coli and S. aureus in milk. Results: The data showed that the nanoparticles used in this study had no effect on the bacteria in the agar medium. However, the results showed that ZnO and MgO nanoparticles resulted in a significant decrease in the number of E. coli (P

  16. Combining the complex variable reproducing kernel particle method and the finite element method for solving transient heat conduction problems

    Institute of Scientific and Technical Information of China (English)

    Chen Li; Ma He-Ping; Cheng Yu-Min

    2013-01-01

    In this paper,the complex variable reproducing kernel particle (CVRKP) method and the finite element (FE) method are combined as the CVRKP-FE method to solve transient heat conduction problems.The CVRKP-FE method not only conveniently imposes the essential boundary conditions,but also exploits the advantages of the individual methods while avoiding their disadvantages,then the computational efficiency is higher.A hybrid approximation function is applied to combine the CVRKP method with the FE method,and the traditional difference method for two-point boundary value problems is selected as the time discretization scheme.The corresponding formulations of the CVRKP-FE method are presented in detail.Several selected numerical examples of the transient heat conduction problems are presented to illustrate the performance of the CVRKP-FE method.

  17. Combined electrochemical, heat generation, and thermal model for large prismatic lithium-ion batteries in real-time applications

    Science.gov (United States)

    Farag, Mohammed; Sweity, Haitham; Fleckenstein, Matthias; Habibi, Saeid

    2017-08-01

    Real-time prediction of the battery's core temperature and terminal voltage is very crucial for an accurate battery management system. In this paper, a combined electrochemical, heat generation, and thermal model is developed for large prismatic cells. The proposed model consists of three sub-models, an electrochemical model, heat generation model, and thermal model which are coupled together in an iterative fashion through physicochemical temperature dependent parameters. The proposed parameterization cycles identify the sub-models' parameters separately by exciting the battery under isothermal and non-isothermal operating conditions. The proposed combined model structure shows accurate terminal voltage and core temperature prediction at various operating conditions while maintaining a simple mathematical structure, making it ideal for real-time BMS applications. Finally, the model is validated against both isothermal and non-isothermal drive cycles, covering a broad range of C-rates, and temperature ranges [-25 °C to 45 °C].

  18. A new heat power plant, and then what?; Een nieuwe warmte/kracht centrale, en dan?

    Energy Technology Data Exchange (ETDEWEB)

    Wentink, J.; Van der Weerd, R.F. [Stork Ketels, Amersfoort (Netherlands)

    1995-07-01

    The operation of the steam supply system of the Heineken brewery in Den Bosch, Netherlands is outlined. Also attention is paid to process and control engineering adjustments that were necessary because of the installation of a 35 MW combined heat and power generating (CHP) system. 2 figs.

  19. Simulated heat waves affected alpine grassland only in combination with drought

    Science.gov (United States)

    De Boeck, Hans J.; Bassin, Seraina; Verlinden, Maya; Zeiter, Michaela; Hiltbrunner, Erika

    2016-04-01

    The Alpine region is warming fast, leading to an increase in the frequency and intensity of climate extremes. Currently, it is unclear whether alpine ecosystems are sensitive or resistant to such extremes. In an experiment carried out in the Swiss Alps, we subjected Swiss alpine grassland communities to heat waves with varying intensity (5-10 °C warming) by transplanting monoliths to four different elevations (2440-660 m a.s.l.) for 17 days. Half of the monoliths were regularly irrigated while the other half were deprived of irrigation to additionally induce a drought at each site. We found that heat waves had no significant short-term impacts on fluorescence (Fv/Fm, a stress indicator), senescence and aboveground productivity if irrigation was provided. However, when heat waves coincided with drought, plants showed clear signs of stress, resulting in vegetation browning and reduced phytomass production. This likely resulted from direct drought effects, but also, as measurements of stomatal conductance and canopy temperatures suggest, from increased high-temperature stress as water scarcity decreased heat mitigation through transpiration. The immediate responses to heat waves (with or without droughts) recorded in these alpine grasslands were similar to those observed in the more extensively studied grasslands from temperate climates. Climate extreme impacts may differ in the longer run, however, because the short growing season in alpine environments likely constrains recovery.

  20. Numerical study of combined convection heat transfer for thermally developing upward flow in a vertical cylinder

    Directory of Open Access Journals (Sweden)

    Mohammed Hussein A.

    2008-01-01

    Full Text Available The problem of the laminar upward mixed convection heat transfer for thermally developing air flow in the entrance region of a vertical circular cylinder under buoyancy effect and wall heat flux boundary condition has been numerically investigated. An implicit finite difference method and the Gauss elimination technique have been used to solve the governing partial differential equations of motion (Navier Stocks equations for two-dimensional model. This investigation covers Reynolds number range from 400 to 1600, heat flux is varied from 70 W/m2 to 400 W/m2. The results present the dimensionless temperature profile, dimensionless velocity profile, dimensionless surface temperature along the cylinder, and the local Nusselt number variation with the dimensionless axial distance Z+. The dimensionless velocity and temperature profile results have revealed that the secondary flow created by natural convection have a significant effect on the heat transfer process. The results have also shown an increase in the Nusselt number values as the heat flux increases. The results have been compared with the available experimental study and with the available analytical solution for pure forced convection in terms of the local Nusselt number. The comparison has shown satisfactory agreement. .

  1. Control of Cimex lectularius using heat combined with dichlorvos resin strips.

    Science.gov (United States)

    Lehnert, M P; Pereira, R M; Koehler, P G; Walker, W; Lehnert, M S

    2011-12-01

    Successful management of the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), is difficult because of its pesticide resistance, which can allow a reduction in population, but not elimination. We evaluated the effect of heat and/or air circulation on the efficacy of dichlorvos resin strips in the control of bed bugs. Treatments were performed in unoccupied dormitory rooms and consisted of dichlorvos resin strips containing 18.6% active ingredient, the same strips + fan, and strips + fan + heat. The mortality of recently fed bed bugs and weight loss of the dichlorvos strips were evaluated over 7 days. Dichlorvos resin strips killed bed bugs and eggs in just over 7 days. The addition of a fan or a fan + heat decreased time to 100% mortality to 3 days and 36 h, respectively. Eggs located in treated rooms did not hatch. Resin strips in the strips + fan treatment and the strips + fan + heat treatment volatilized 10 and 70 times, respectively, faster than strips in the strips-only treatment. The addition of heat in treatments with dichlorvos resin strips enhances the overall efficacy of the volatile insecticide and reduces the time required to eliminate live bed bugs and eggs.

  2. Enzyme inactivation analysis for industrial blanching applications: comparison of microwave, conventional, and combination heat treatments on mushroom polyphenoloxidase activity.

    Science.gov (United States)

    Devece, C; Rodríguez-López, J N; Fenoll, L G; Tudela, J; Catalá, J M; de Los Reyes, E; García-Cánovas, F

    1999-11-01

    Browning reactions in fruits and vegetables are a serious problem for the food industry. In mushrooms, the principal enzyme responsible for the browning reaction is polyphenoloxidase (PPO). Microwaves have recently been introduced as an alternative for the industrial blanching of mushrooms. However, the direct application of microwave energy to entire mushrooms is limited by the important temperature gradients generated within the samples during heating, which can produce internal water vaporization and associated damage to the mushrooms texture. A microwave applicator has been developed, whereby irradiation conditions can be regulated and the heating process monitored. Whole edible mushrooms (Agaricus bisporus) were blanched by conventional, microwave, and combined heating methods to optimize the rate of PPO inactivation. A combined microwave and hot-water bath treatment has achieved complete PPO inactivation in a short time. Both the loss of antioxidant content and the increase of browning were minor in the samples treated with this combined method when compared to the control. This reduction in processing time also decreased mushroom weight loss and shrinkage.

  3. Exergy analysis of the woody biomass Stirling engine and PEM-FC combined system with exhaust heat reforming

    Energy Technology Data Exchange (ETDEWEB)

    Obara, Shin' ya; Tanno, Itaru [Department of Mechanical Engineering, Tomakomai National College of Technology, 443 Nishikioka, Tomakomai, Hokkaido 0591275 (Japan); Kito, Shunsuke [Department of Mechanical Engineering, Toyota National College of Technology, Eisei-cho, 2-1 Toyota, Aichi 4718525 (Japan); Hoshi, Akira; Sasaki, Seizi [Department of Mechanical Engineering, Ichinoseki National College of Technology, Takanashi, Hagisho, Ichinoseki, Iwate 0218511 (Japan)

    2008-05-15

    The woody biomass Stirling engine (WB-SEG) is an external combustion engine that outputs high-temperature exhaust gases. It is necessary to improve the exergy efficiency of WB-SEG from the viewpoint of energy cascade utilization. So, a combined system that uses the exhaust heat of WB-SEG for the steam reforming of city gas and that supplies the produced reformed gas to a proton exchange membrane fuel cell (PEM-FC) is proposed. The energy flow and the exergy flow were analyzed for each WB-SEG, PEM-FC, and WB-SEG/PEM-FC combined system. Exhaust heat recovery to preheat fuel and combustion air was investigated in each system. As a result, (a) improvement of the heat exchange performance of the woody biomass combustion gas and engine is observed, (b) reduction in difference in the reaction temperature of each unit, and (c) removal of rapid temperature change of reformed gas are required in order to reduce exergy loss of the system. The exergy efficiency of the WB-SEG/PEM-FC combined system is superior to EM-FC. (author)

  4. Effects of Combined Heat and Preservative Treatment on Storability of Ponkan Fruit (Citrus reticulata Blanco cv. Ponkan during Postharvest Storage

    Directory of Open Access Journals (Sweden)

    Dandan Tang

    2017-01-01

    Full Text Available Heat treatment and preservative application have been widely used during postharvest storage of many fresh products, but the effect of their combination on citrus storage has rarely been investigated. In this study, the optimal heat treatment (HT conditions and HT combined with preservative treatment were investigated for Ponkan fruit (Citrus reticulata Blanco cv. Ponkan storage. Results indicated that HT at 55°C for 20 s can significantly reduce the decay rate of Ponkan fruit, and a combination of HT and 25% of the preservative dosage used in production of iminoctadine tris (albesilate, 2,4-dichlorophenoxyacetic acid, and imazalil significantly reduced the decay rate without affecting fruit quality. In addition, the increased fiber contents in fruit receiving the HT combined with preservative treatments may be a response preventing fungus infection and enhancing fruit storability and resistance. The above results suggested that the combination of HT and 25% of the preservative production dosage was optimal for controlling Ponkan fruit decay during storage.

  5. 1.5 MW RF Load for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Ives, Robert Lawrence [Calabazas Creek Research, Inc., San Mateo, CA (United States); Marsden, David [Calabazas Creek Research, Inc., San Mateo, CA (United States); Collins, George [Calabazas Creek Research, Inc., San Mateo, CA (United States); Karimov, Rasul [Calabazas Creek Research, Inc., San Mateo, CA (United States); Mizuhara, Max [Calabazas Creek Research, Inc., San Mateo, CA (United States); Neilson, Jeffrey [Lexam Research, Redwood City, CA (United States)

    2016-09-01

    Calabazas Creek Research, Inc. developed a 1.5 MW RF load for the ITER fusion research facility currently under construction in France. This program leveraged technology developed in two previous SBIR programs that successfully developed high power RF loads for fusion research applications. This program specifically focused on modifications required by revised technical performance, materials, and assembly specification for ITER. This program implemented an innovative approach to actively distribute the RF power inside the load to avoid excessive heating or arcing associated with constructive interference. The new design implemented materials and assembly changes required to meet specifications. Critical components were built and successfully tested during the program.

  6. ComfortPower. Design, construction and evaluation of a combined fuel-cell and heat pump system

    Energy Technology Data Exchange (ETDEWEB)

    Silversand, Fredrik (Catator AB, Lund (Sweden))

    2010-12-15

    Catator AB has constructed, commissioned and evaluated a combined fuel-cell and heat-pump system (ComfortPower). The basic idea behind the project was to demonstrate the possibility to achieve ultrahigh thermal efficiencies when combining fuel-cell technologies and heat pumps. Moreover, the system should provide a great flexibility with respect to the fuel mix and should in addition to heat provide surplus electricity and cooling. The system was built on a HT-PEM platform (high temperature polymer electrolyte fuel cell from Serenergy a/s), which was operated by Catators proprietary Optiformer technology. The power generator was combined with a heat pump module (F1145-5, 230 V), supplied by Nibe. The system was packaged into a cabinet (1.65 x 0.6 x 0.6 m) comprising the power module, the heat pump, all necessary balance-of-plant components and the control system. The power output from the fuel-cell system was around 1.35 kW, which enabled operation of the heat pump compressor. By utilizing surplus heat energy from the fuel cell it was possible to achieve a favourable operation point in the heat pump system, resulting in a high overall COP (coefficient of performance). The heat output from the system was as high as 10 kW whereas 6 kW cooling could be provided. The thermal efficiencies measured in experiments were normally around 200%, calculated on the lower heating value of the fuel. A number of fuels have been investigated in the fuel cell system, including both gaseous (natural gas/LPG) and liquid fuels (alcohols and kerosene). Indeed, the system has a wide fuel flexibility, which opens up for a variety of applications in campus villages and buildings. This study has demonstrated the possibility to reduce the carbon dioxide footprint by a factor of 2 over conventional boilers in heating applications. In addition the unit can be operated on a variety of fuels and can produce cooling and electricity in addition to heat. A fully working system has been designed

  7. LBNF 1.2 MW TARGET: CONCEPTUAL DESIGN & FABRICATION

    Energy Technology Data Exchange (ETDEWEB)

    Crowley, Cory F. [Fermilab; Ammigan, K. [Fermilab; Anderson, K. [Fermilab; Hartsell, B. [Fermilab; Hurh, P. [Fermilab; Hylen, J. [Fermilab; Zwaska, R. [Fermilab

    2015-06-29

    Fermilab’s Long-Baseline Neutrino Facility (LBNF) will utilize a modified design based on the NuMI low energy target that is reconfigured to accommodate beam operation at 1.2 MW. Achieving this power with a graphite target material and ancillary systems originally rated for 400 kW requires several design changes and R&D efforts related to material bonding and electrical isolation. Target cooling, structural design, and fabrication techniques must address higher stresses and heat loads that will be present during 1.2 MW operation, as the assembly will be subject to cyclic loads and thermal expansion. Mitigations must be balanced against compromises in neutrino yield. Beam monitoring and subsystem instrumentation will be updated and added to ensure confidence in target positioning and monitoring. Remote connection to the target hall support structure must provide for the eventual upgrade to a 2.4 MW target design, without producing excessive radioactive waste or unreasonable exposure to technicians during reconfiguration. Current designs and assembly layouts will be presented, in addition to current findings on processes and possibilities for prototype and final assembly fabrication.

  8. Subcontract Report: Modular Combined Heat & Power System for Utica College: Design Specification

    Energy Technology Data Exchange (ETDEWEB)

    Rouse, Greg [Gas Technology Institute

    2007-09-01

    Utica College, located in Utica New York, intends to install an on-site power/cogeneration facility. The energy facility is to be factory pre-assembled, or pre- assembled in modules, to the fullest extent possible, and ready to install and interconnect at the College with minimal time and engineering needs. External connections will be limited to fuel supply, electrical output, potable makeup water as required and cooling and heat recovery systems. The proposed facility will consist of 4 self-contained, modular Cummins 330kW engine generators with heat recovery systems and the only external connections will be fuel supply, electrical outputs and cooling and heat recovery systems. This project was eventually cancelled due to changing DOE budget priorities, but the project engineers produced this system design specification in hopes that it may be useful in future endeavors.

  9. Energy and Exergy Analysis and Optimization of Combined Heat and Power Systems. Comparison of Various Systems

    Directory of Open Access Journals (Sweden)

    Monica Costea

    2012-09-01

    Full Text Available The paper presents a comparison of various CHP system configurations, such as Vapour Turbine, Gas Turbine, Internal Combustion Engine, External Combustion Engine (Stirling, Ericsson, when different thermodynamic criteria are considered, namely the first law efficiency and exergy efficiency. Thermodynamic optimization of these systems is performed intending to maximize the exergy, when various practical related constraints (imposed mechanical useful energy, imposed heat demand, imposed heat to power ratio or main physical limitations (limited heat availability, maximum system temperature allowed, thermo-mechanical constraints are taken into account. A sensitivity analysis to model parameters is given. The results have shown that the various added constraints were useful for the design allowing to precise the influence of the model main parameters on the system design. Future perspective of the work and recommendations are stated.

  10. Brief introduction to 60 MW CARR

    Energy Technology Data Exchange (ETDEWEB)

    Yang Tonghua; Ye Chuntang [China Inst. of Atomic Energy, Beijing BJ (China)

    1998-10-01

    CARR, a 60 MW reactor will be constructed at China Institute of Atomic Energy (CIAE). The reactor type, its safety features, core lay-out, fuel assemblies, main parameters designed, main applications of are briefly described. (author)

  11. Plasma hyperosmolality improves tolerance to combined heat stress and central hypovolemia in humans.

    Science.gov (United States)

    Gagnon, Daniel; Romero, Steven A; Ngo, Hai; Poh, Paula Y S; Crandall, Craig G

    2017-03-01

    Heat stress profoundly impairs tolerance to central hypovolemia in humans via a number of mechanisms including heat-induced hypovolemia. However, heat stress also elevates plasma osmolality; the effects of which on tolerance to central hypovolemia remain unknown. This study examined the effect of plasma hyperosmolality on tolerance to central hypovolemia in heat-stressed humans. With the use of a counterbalanced and crossover design, 12 subjects (1 female) received intravenous infusion of either 0.9% iso-osmotic (ISO) or 3.0% hyperosmotic (HYPER) saline. Subjects were subsequently heated until core temperature increased ~1.4°C, after which all subjects underwent progressive lower-body negative pressure (LBNP) to presyncope. Plasma hyperosmolality improved LBNP tolerance (ISO: 288 ± 193 vs. 382 ± 145 mmHg × min, P = 0.04). However, no differences in mean arterial pressure (P = 0.10), heart rate (P = 0.09), or muscle sympathetic nerve activity (P = 0.60, n = 6) were observed between conditions. When individual data were assessed, LBNP tolerance improved ≥25% in eight subjects but remained unchanged in the remaining four subjects. In subjects who exhibited improved LBNP tolerance, plasma hyperosmolality resulted in elevated mean arterial pressure (ISO: 62 ± 10 vs. 72 ± 9 mmHg, P < 0.01) and a greater increase in heart rate (ISO: +12 ± 24 vs. HYPER: +23 ± 17 beats/min, P = 0.05) before presyncope. No differences in these variables were observed between conditions in subjects that did not improve LBNP tolerance (all P ≥ 0.55). These results suggest that plasma hyperosmolality improves tolerance to central hypovolemia during heat stress in most, but not all, individuals. Copyright © 2017 the American Physiological Society.

  12. The Utilisation of Solar System in Combined Heating System of Water

    Directory of Open Access Journals (Sweden)

    Ján Jobbágy

    2017-01-01

    Full Text Available The paper assessed the topicality and returns of solar system utilization to heating of water. Practical measurements were conducted after reconstruction of the family house. (in Nesvady, Slovak republic, on which the solar system were assembled. The system consists of the gas heater, solar panels, distributions and circulation pump. The solar system was assembled due to decreasing of operation costs and connected with conventional already used gas heating system by boiler Quantum (V = 115 L. The conventional system was used for 21 days to gather basic values for evaluation. At this point it was observed that 11.93 m3 of gas is needed to heat up 1 m3 of water. Used water in this case was heated from initial 16.14 °C to 52.04 °C of output temperature. Stand by regime of boiler was characterized by 0.012 m3.h-1 consumption of gas. The rest of the measurements represent the annual (from 03/2013 to 02/2014 operation process of boiler Tatramat VTS 200L (trivalent with 200 litres of volume (as a part of Thermosolar solar system. The solar collectors TS 300 are also part of the solar system. An input and output temperatures of heating water we observed along with water and gas consumption, intensity of solar radiation and actual weather conditions. The amount of heat produced by solar system was then calculated. Total investment on solar system were 2,187.7 € (1,475.7 € with subsidy. Therefore, return on investment for the construction of the solar system was set at 23 years even with subsidy.

  13. Combined scheduling of electricity and heat in a microgrid with volatile wind power

    DEFF Research Database (Denmark)

    Xu, Lizhong; Yang, Guang Ya; Xu, Zhao

    2011-01-01

    An optimization model is developed for scheduling electricity and heat production in a microgrid under a day-ahead market environment considering the operation constraints and the volatility of wind power generation. The model optimizes the total operation costs from energy and heating consumption...... into a mixed-integer programming (MIP) problem. Numerical simulations present the efficacy of the proposed model for day-ahead scheduling of a microgrid with wind penetration under the deregulated environment. © 2011 State Grid Electrtic Resarch Institute Press....

  14. A study of graphite ablation in combined convective and radiative heating.

    Science.gov (United States)

    Wakefield, R. M.; Peterson, D. L.

    1972-01-01

    Comparison of graphite ablation experiment results in the diffusion-controlled oxidation and sublimation regimes with results of an equilibrium chemistry, film coefficient ablation analysis. Mass transfer and energy transfer effects are considered. Tests were conducted in an arcjet facility at convective heating rates of 600 to 800 W/sq cm, radiative heating rates up to 2900 W/sq cm, with test specimen surface pressures of 0.06, 0.1, and 0.3 atm in an air stream. The experimental and analytical mass loss and surface temperature results agreed well when the carbon vapor thermodynamic properties from the JANAF tables are used in the analysis.

  15. Heat piles - a combination of geotechnical and geothermal engineering; Energiepfaehle - Verbindung von Geotechnik und Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Katzenbach, R.; Rueckert, A. [Technische Univ. Darmstadt (Germany). Inst. fuer Geotechnik; Knoblich, K.; Sanner, B. [Giessen Univ. (Germany). Inst. fuer Angewandte Geowissenschaften; Mands, E. [Prof. Dr. Knoblich und Partner GmbH, Wetzlar (Germany)

    1997-12-01

    The numerical programs used for borehole heat exchangers are also suitable to simulate the performance of heat piles, provided they permit a differentiation of thermal properties in the vicinity of the heat exchanger pipes. Adaptations of known programs for heat piles have been described by PAHUD and FROMENTIN (1997). For simple pile geometries, the program EED can be used as well (HELLSTROeM et al., 1997), as it permits very quick determination of the potentials for heat extraction and energy supply. Because of their geotechnical function, such systems should only be made use of where heating and cooling can be planned with sufficient accuracy, giving an idea of the likely temperatures in the piles. Further, the static function of the piles needs to be kept in mind. If adequately used, heat piles offer a huge potential for practically all types of buildings erected in sites requiring deep foundations or where the excavation for the foundation needs to be enclosed. In Germany alone 5000 buildings are erected each year which would permit non-depleting use of the thermal energy bottled up in the ground and ground water via heat piles. (orig.) [Deutsch] Zur Simuliation des Betriebsverhaltens von Energiepfahlanlagen eigenen sich die auch fuer Erdwaermesonden verwendeten numerischen Programme, vorausgesetzt, sie lassen eine Differenzierung der thermischen Eigenschaften im Nahbereich der Waermetauscherrohre zu. Anpassungen von bekannten Programmen im Hinblick auf Energiepfaehle schildern PAHUD and FROMENTIN (1997). Fuer einfache Pfahlgeometrien kann auch das Programm EED herangezogen werden (HELLSTROeM et al., 1997), mit dem sich sehr schnell die moeglichen Entzugs- und Einspeiseleistungen ermitteln lassen. Wegen der vorrangigen geotechnischen Bedeutung sollten Energiepfaehle nur im Rahmen einer ausreichend genauen Heizungs-/Kuehlungsplanung vorgesehen werden, die einen Eindruck der zu erwartenden Temperaturen in den Phaehlen geben kann. Ausserdem ist immer zu beachten

  16. Integration of A Solid Oxide Fuel Cell into A 10 MW Gas Turbine Power Plant

    Directory of Open Access Journals (Sweden)

    Denver F. Cheddie

    2010-04-01

    Full Text Available Power generation using gas turbine power plants operating on the Brayton cycle suffers from low efficiencies. In this work, a solid oxide fuel cell (SOFC is proposed for integration into a 10 MW gas turbine power plant, operating at 30% efficiency. The SOFC system utilizes four heat exchangers for heat recovery from both the turbine outlet and the fuel cell outlet to ensure a sufficiently high SOFC temperature. The power output of the hybrid plant is 37 MW at 66.2% efficiency. A thermo-economic model predicts a payback period of less than four years, based on future projected SOFC cost estimates.

  17. A survey of drag and heat reduction in supersonic flows by a counterflowing jet and its combinations

    Institute of Scientific and Technical Information of China (English)

    Wei HUANG

    2015-01-01

    题目:逆向喷流及其组合体在超声速气流中减阻防热功效研究进展  概总结归纳国内外逆向喷流及其组合体在超声速气流中减阻防热功效的研究进展,并给出逆向喷流在某些应用领域的建议,特别是喷流的不稳定性保护、减阻与热防护之间的权衡以及流动模态转换的工作参数和结构参数临界点选取等。%Drag reduction and thermal protection is very important for hypersonic vehicles, and a counterflowing jet and its combinations is one of the most promising drag and heat release reduction strategies. In the current survey, research progress on the drag and heat release reduction induced by a counterflowing jet and its combinations is summarized. Three combinatorial configurations are considered, namely the combination of the counterflowing jet and a forward-facing cavity, the combination of the counterflowing jet and an aerospike, and the combination of the counterflowing jet and energy deposition. In conclusion, some recommendations are provided, especially for jet instability protection, for the tradeoff between drag and heat release re-ductions, and for the critical points for the operational and geometric parameters in the flow mode transition.

  18. Analysis of combined hydrogen, heat, and power as a bridge to a hydrogen transition.

    Energy Technology Data Exchange (ETDEWEB)

    Mahalik, M.; Stephan, C. (Decision and Information Sciences)

    2011-01-18

    Combined hydrogen, heat, and power (CHHP) technology is envisioned as a means to providing heat and electricity, generated on-site, to large end users, such as hospitals, hotels, and distribution centers, while simultaneously producing hydrogen as a by-product. The hydrogen can be stored for later conversion to electricity, used on-site (e.g., in forklifts), or dispensed to hydrogen-powered vehicles. Argonne has developed a complex-adaptive-system model, H2CAS, to simulate how vehicles and infrastructure can evolve in a transition to hydrogen. This study applies the H2CAS model to examine how CHHP technology can be used to aid the transition to hydrogen. It does not attempt to predict the future or provide one forecast of system development. Rather, the purpose of the model is to understand how the system works. The model uses a 50- by 100-mile rectangular grid of 1-square-mile cells centered on the Los Angeles metropolitan area. The major expressways are incorporated into the model, and local streets are considered to be ubiquitous, except where there are natural barriers. The model has two types of agents. Driver agents are characterized by a number of parameters: home and job locations, income, various types of 'personalities' reflective of marketing distinctions (e.g., innovators, early adopters), willingness to spend extra money on 'green' vehicles, etc. At the beginning of the simulations, almost all driver agents own conventional vehicles. They drive around the metropolitan area, commuting to and from work and traveling to various other destinations. As they do so, they observe the presence or absence of facilities selling hydrogen. If they find such facilities conveniently located along their routes, they are motivated to purchase a hydrogen-powered vehicle when it becomes time to replace their present vehicle. Conversely, if they find that they would be inconvenienced by having to purchase hydrogen earlier than necessary or if they

  19. Analysis of combined hydrogen, heat, and power as a bridge to a hydrogen transition.

    Energy Technology Data Exchange (ETDEWEB)

    Mahalik, M.; Stephan, C. (Decision and Information Sciences)

    2011-01-18

    Combined hydrogen, heat, and power (CHHP) technology is envisioned as a means to providing heat and electricity, generated on-site, to large end users, such as hospitals, hotels, and distribution centers, while simultaneously producing hydrogen as a by-product. The hydrogen can be stored for later conversion to electricity, used on-site (e.g., in forklifts), or dispensed to hydrogen-powered vehicles. Argonne has developed a complex-adaptive-system model, H2CAS, to simulate how vehicles and infrastructure can evolve in a transition to hydrogen. This study applies the H2CAS model to examine how CHHP technology can be used to aid the transition to hydrogen. It does not attempt to predict the future or provide one forecast of system development. Rather, the purpose of the model is to understand how the system works. The model uses a 50- by 100-mile rectangular grid of 1-square-mile cells centered on the Los Angeles metropolitan area. The major expressways are incorporated into the model, and local streets are considered to be ubiquitous, except where there are natural barriers. The model has two types of agents. Driver agents are characterized by a number of parameters: home and job locations, income, various types of 'personalities' reflective of marketing distinctions (e.g., innovators, early adopters), willingness to spend extra money on 'green' vehicles, etc. At the beginning of the simulations, almost all driver agents own conventional vehicles. They drive around the metropolitan area, commuting to and from work and traveling to various other destinations. As they do so, they observe the presence or absence of facilities selling hydrogen. If they find such facilities conveniently located along their routes, they are motivated to purchase a hydrogen-powered vehicle when it becomes time to replace their present vehicle. Conversely, if they find that they would be inconvenienced by having to purchase hydrogen earlier than necessary or if they

  20. Experimental investigations of heat transfer in thermo active building systems in combination with suspended ceilings

    DEFF Research Database (Denmark)

    Alvarez, Maria Alonso; Hviid, Christian Anker; Weitzmann, Peter

    2014-01-01

    Thermo Active Building Systems (TABS), described as radiant heating or cooling systems with pipes embedded in the building structure, represent a sustainable alternative to replace conventional systems by using source temperatures close to room temperatures. The use of suspended ceiling in office...

  1. Climatic impact of urbanization in Eastern China: modeling the combined urban heat island and aerosol effects

    Science.gov (United States)

    Qian, Y.; Yang, B.; Zhao, C.; Leung, L. R.; Yan, H.; Fan, J.

    2014-12-01

    In this study we investigate the climatic impact of urbanization, including both Urban Heat Island (UHI) and aerosol effects, over the Yangtze-Delta metropolitan clusters region of Eastern China, based on a series of simulations with prescribed land use/land cover and emissions of aerosols and their precursors for the 2000s and 1970s , respectively. We conduct simulations for each land use/land cover and emission scenario from 2006-2010 using the Weather Research and Forecasting (WRF) model, with online chemistry/aerosol and urban canopy models, at a 3-km grid spacing. Overall the model can reasonably capture the spatial pattern of temperature and precipitation as well as the phase of precipitation diurnal cycle in summer. Simulations results show a very clear UHI effect, i.e. expanded urban surface decreases surface latent heat flux, increases sensible heat flux and PBL height, and reduces surface wind over urban areas, with a more significant change in summer. Aerosol has much less obvious impact on local surface heat flux and temperature, but shows more remote impacts downwind due to dispersion and transport of pollutants and aerosol-cloud interaction. Aerosol also has a larger impact on precipitation amount and areal coverage than UHI. While UHI increases precipitation over urban regions during daytime especially when the southeasterly monsoonal flow prevails, aerosol remarkably suppresses precipitation, especially for light to moderate rain events, and increases the frequency of dry days in the entire model region.

  2. Combined effects of heat waves and droughts on avian communities across the conterminous United States

    Science.gov (United States)

    Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Brian D. Wardlow; Curtis H. Flather; Patrick D. Culbert; Volker C. Radeloff

    2010-01-01

    Increasing surface temperatures and climatic variability associated with global climate change are expected to produce more frequent and intense heat waves and droughts in many parts of the world. Our goal was to elucidate the fundamental, but poorly understood, effects of these extreme weather events on avian communities across the conterminous United States....

  3. A comparison of advanced heat recovery power cycles in a combined cycle for large ships

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Sigthorsson, Oskar; Haglind, Fredrik

    2014-01-01

    Strong motivation exists within the marine sector to reduce fuel expenses and to comply with ever stricter emission regulations. Heat recovery can address both of these issues. The ORC (organic Rankine cycle), the Kalina cycle and the steam Rankine cycle have received the majority of the focus in...

  4. Bendamustine and rituximab combination in the management of chronic lymphocytic leukemia-associated autoimmune hemolytic anemia: a multicentric retrospective study of the French CLL intergroup (GCFLLC/MW and GOELAMS).

    Science.gov (United States)

    Quinquenel, Anne; Willekens, Christophe; Dupuis, Jehan; Royer, Bruno; Ysebaert, Loic; De Guibert, S; Michallet, Anne-Sophie; Feugier, Pierre; Guieze, Romain; Levy, Vincent; Delmer, Alain

    2015-03-01

    We report our experience on bendamustine and rituximab (BR) combination in 26 patients with chronic lymphocytic leukemia (CLL) complicated by autoimmune hemolytic anemia (AIHA). At the time of BR initiation, 88% of the patients had already been treated for AIHA and CLL was progressive regardless of AIHA in all patients but one. Overall response rates were 81% for AIHA and 77% for CLL. Median time to next treatment was 28.3 months and 26.2 months for AIHA and CLL, respectively. BR therapy may represent a good and safe therapeutic option in this setting where adequate control of CLL seems important for long-term AIHA response.

  5. Heat flow and thermal maturity in the Williston Basin

    Energy Technology Data Exchange (ETDEWEB)

    Gosnold, W.; LeFever, R. [North Dakota Univ., Grand Forks, ND (United States)

    2009-07-01

    This presentation discussed steady-state heat sources, transient disturbances, and the chemical kinetics and hydrocarbon potential of the Williston Basin. Global average heat flow has been estimated at 87 mW per m{sup 2}, while total surface heat flux is 44.2 x TW. Heat flow within ocean basins correlates with age, while heat flow on continents is related to radioactive heat production in the continental crust. The mantle flux of the continental crust averages 27 mW per m{sup 2}. Heat flow correlates with tectonic age. Transient signals in continental heat flow include groundwater flow, ground cover changes, and climatic changes. However, subsurface temperatures can be calculated when heat flow and thermal conductivity are known, using Fourier's law of heat conduction. Thermal maturity is a measure of the degree of kerogen metamorphism in a formation, and can provide an estimate of the maximum temperature that a formation has reached when combined with an understanding of chemical kinetics and thermal history. The kinetic reaction rate depends on the absolute temperature as well as the amount of reactants. The reaction rate is a function of absolute temperature, frequency factor, and activation energy. The hydrocarbon potential can then be estimated for different kerogen types across a range of activation energies. tabs., figs.

  6. Thermal tests of the SGT5-4000F gas-turbine plant of the PGU-420T power-generating unit at Combined Heat And Power Plant 16 of Mosenergo

    Science.gov (United States)

    Teplov, B. D.; Radin, Yu. A.; Filin, A. A.; Rudenko, D. V.

    2016-08-01

    In December 2014, the PGU-420T power-generating unit was put into operation at the Combined Heat and Power Plant 16, an affiliated company of PAO Mosenergo. In 2014-2015, thermal tests of the SGT5- 4000F gas-turbine plant (GTP) integrated into the power-generating unit were carried out. In the article, the test conditions are described and the test results are presented and analyzed. During the tests, 92 operating modes within a wide range of electrical loads and ambient air temperatures and operating conditions of the GTP when fired with fuel oil were investigated. In the tests, an authorized automated measuring system was applied. The experimental data were processed according to ISO 2314:2009 "Gas turbines—Acceptance tests" standard. The available capacity and the GTP efficiency vary from 266 MW and 38.8% to 302 MW and 39.8%, respectively, within the ambient air temperature range from +24 to-12°C, while the turbine inlet temperature decreases from 1200 to 1250°C. The switch to firing fuel oil results in a reduction in the turbine inlet temperature and the capacity of the GTP. With the full load and a reduction in the ambient temperature from +24 to-12°C, the compressor efficiency decreases from 89.6 to 86.4%. The turbine efficiency is approximately 89-91%. Within the investigated range of power output, the emissions of nitrogen oxides do not exceed 35 ppm for the gas-fired plant and 65 ppm for the fuel-oil-fired plant. Within the range of the GTP power output from 50 to 100% of the rated output, the combustion chamber operates without underburning and with hardly any CO being formed. At low loads close to the no-load operation mode, the CO emissions drastically increase.

  7. State of the Art Treatment of Non-Ferrous Castings 3-in-1 Heat Treatment Systems Combine Foundry Processes

    Institute of Scientific and Technical Information of China (English)

    Volker R. Knobloch

    2004-01-01

    The interior of a high-pressure die-casting is of an unsatisfactory quality. Engine blocks made with this die casting process show lower specific engine performance. Pressure die-casting can hardly be heat treated for obvious reasons.PSM (Precision Sand Molds) process uses sand and organic binder to generate a mold and even allows the manufacturing of complex diesel engine blocks in aluminum alloys. Combined technologies are available for semi-permanent mold castings with cores and castings made in Precision Sand Molds with organic binders. Castings are placed into the special heat treatment furnace immediately after pouring without the operations in stand alone machinery. This patented Sand Lion(R) 3-in-1 technology processes hot castings and carries out three (3) foundry processes simultaneously in one (1) automated machine: 1) De-coring and sand removal; 2) Thermal sand reclamation; 3) Solution heat treatment of castings. The combination of several main casting processes is reflected in significant reductions of energy consumption, of production costs, and improving the quality of the castings. Audits in foundries using the 3-in-1 process showed an average reduction in production costs of more than 30%.

  8. Enhanced detection of nitrogen dioxide via combined heating and pulsed UV operation of indium oxide nano-octahedra.

    Science.gov (United States)

    Gonzalez, Oriol; Roso, Sergio; Vilanova, Xavier; Llobet, Eduard

    2016-01-01

    We report on the use of combined heating and pulsed UV light activation of indium oxide gas sensors for enhancing their performance in the detection of nitrogen dioxide in air. Indium oxide nano-octahedra were synthesized at high temperature (900 °C) via vapour-phase transport and screen-printed onto alumina transducers that comprised interdigitated electrodes and a heating resistor. Compared to the standard, constant temperature operation of the sensor, mild heating (e.g., 100 °C) together with pulsed UV light irradiation employing a commercially available, 325 nm UV diode (square, 1 min period, 15 mA drive current signal), results in an up to 80-fold enhancement in sensitivity to nitrogen dioxide. Furthermore, this combined operation method allows for making savings in power consumption that range from 35% to over 80%. These results are achieved by exploiting the dynamics of sensor response under pulsed UV light, which convey important information for the quantitative analysis of nitrogen dioxide.

  9. Enhanced detection of nitrogen dioxide via combined heating and pulsed UV operation of indium oxide nano-octahedra

    Directory of Open Access Journals (Sweden)

    Oriol Gonzalez

    2016-10-01

    Full Text Available We report on the use of combined heating and pulsed UV light activation of indium oxide gas sensors for enhancing their performance in the detection of nitrogen dioxide in air. Indium oxide nano-octahedra were synthesized at high temperature (900 °C via vapour-phase transport and screen-printed onto alumina transducers that comprised interdigitated electrodes and a heating resistor. Compared to the standard, constant temperature operation of the sensor, mild heating (e.g., 100 °C together with pulsed UV light irradiation employing a commercially available, 325 nm UV diode (square, 1 min period, 15 mA drive current signal, results in an up to 80-fold enhancement in sensitivity to nitrogen dioxide. Furthermore, this combined operation method allows for making savings in power consumption that range from 35% to over 80%. These results are achieved by exploiting the dynamics of sensor response under pulsed UV light, which convey important information for the quantitative analysis of nitrogen dioxide.

  10. Two Examples of Exergy Optimization Regarding the “Thermo-Frigopump” and Combined Heat and Power Systems

    Directory of Open Access Journals (Sweden)

    Michel Feidt

    2013-02-01

    Full Text Available In a recent review an optimal thermodynamics and associated new upper bounds have been proposed, but it was only relative to power delivered by engines. In fact, it appears that for systems and processes with more than one utility (mainly mechanical or electrical power, energy conservation (First Law is limited for representing their efficiency. Consequently, exergy analysis combining the First and Second Law seems essential for optimization of systems or processes situated in their environment. For thermomechanical systems recent papers report on comparisons between energy and exergy analysis and corresponding optimization, but the proposed models mainly use heat transfer conductance modelling, except for internal combustion engine. Here we propose to reconsider direct and inverse configurations of Carnot machines, with two examples. The first example is concerned with “thermofrigo-pump” where the two utilities are hot and cold thermal exergies due to the difference in the temperature level compared to the ambient one. The second one is relative to a “combined heat and power” (CHP system. In the two cases, the model is developed based on the Carnot approach, and use of the efficiency-NTU method to characterize the heat exchangers. Obtained results are original thermodynamics optima, that represent exergy upper bounds for these two cases. Extension of the proposed method to other systems and processes is examined, with added technical constraints or not.

  11. Life cycle analysis of distributed concentrating solar combined heat and power: economics, global warming potential and water

    Science.gov (United States)

    Norwood, Zack; Kammen, Daniel

    2012-12-01

    We report on life cycle assessment (LCA) of the economics, global warming potential and water (both for desalination and water use in operation) for a distributed concentrating solar combined heat and power (DCS-CHP) system. Detailed simulation of system performance across 1020 sites in the US combined with a sensible cost allocation scheme informs this LCA. We forecast a levelized cost of 0.25 kWh-1 electricity and 0.03 kWh-1 thermal, for a system with a life cycle global warming potential of ˜80 gCO2eq kWh-1 of electricity and ˜10 gCO2eq kWh-1 thermal, sited in Oakland, California. On the basis of the economics shown for air cooling, and the fact that any combined heat and power system reduces the need for cooling while at the same time boosting the overall solar efficiency of the system, DCS-CHP compares favorably to other electric power generation systems in terms of minimization of water use in the maintenance and operation of the plant. The outlook for water desalination coupled with distributed concentrating solar combined heat and power is less favorable. At a projected cost of 1.40 m-3, water desalination with DCS-CHP would be economical and practical only in areas where water is very scarce or moderately expensive, primarily available through the informal sector, and where contaminated or salt water is easily available as feed-water. It is also interesting to note that 0.40-1.90 m-3 is the range of water prices in the developed world, so DCS-CHP desalination systems could also be an economical solution there under some conditions.

  12. Experimental study including subjective evaluations of mixing and displacement ventilation combined with radiant floor heating/cooling system

    DEFF Research Database (Denmark)

    Krajcik, Michal; Tomasi, Roberta; Simone, Angela

    2013-01-01

    mixing ventilation systems was found. The next two tests simulated an office room during summer, ventilated and cooled either by a displacement ventilation system alone or by a displacement ventilation system combined with radiant floor cooling. Displacement ventilation combined with floor cooling had...... lower floor temperature, warmer supply air, and less homogeneous vertical temperature profile, but it did not result in thermal discomfort on feet/lower legs or discomfort due to a vertical air temperature difference higher than for a displacement ventilation system alone, where the floor temperature......Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation systems and radiant heating/cooling systems. In the first two tests, the simulated residential room was equipped either by a mixing ventilation system supplying warm air for space...

  13. Combined Microwave and Sferics Measurements as a Continuous Proxy for Latent Heating in Mesoscale Model Predictions

    Science.gov (United States)

    Chang, D. -E.; Morales, C. A.; Weinman, J. A.; Olson, W. S.

    1999-01-01

    Planar rainfall distributions were retrieved from data provided by the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and Special Sensor Microwave Imager (SSM/I) radiometers. Lightning generates Very Low Frequency (VLF) radio noise pulses called sferics. Those pulses propagate over large distances so that they can be continuously monitored with a network of ground based radio receivers. An empirical relationship between the sferics rate and the convective rainfall permitted maps of convective latent heating profiles to be derived continuously from the sferics distributions. Those inferred latent heating rates were assimilated into the Penn State/NCAR Mesoscale Model (MM5) that depicted an intense winter cyclone that passed over Florida on 2 February 1998. When compared to a 14 hour MM5 rainfall forecast using conventional data, the use of lightning data improved the forecast.

  14. Successful Treatment of Cutaneous Botryomycosis with a Combination of Minocycline and Topical Heat Therapy

    Directory of Open Access Journals (Sweden)

    Masaya Ishibashi

    2012-05-01

    Full Text Available Cutaneous botryomycosis is a chronic focal infection characterized by a granulomatous inflammatory response to bacterial pathogens such as Staphylococcus aureus. Treatment requires antibiotic therapy and may also require surgical debridement. We employed topical heat therapy and oral minocycline. The lesions became flattened and pigmented after 1 month. We consider that this simple treatment can be an effective and harmless complementary therapy for cutaneous botryomycosis.

  15. A dynamic regrouping based sequential dynamic programming algorithm for unit commitment of combined heat and power systems

    DEFF Research Database (Denmark)

    Rong, Aiying; Hakonen, Henri; Lahdelma, Risto

    2009-01-01

    This paper addresses the unit commitment (UC) in multi-period combined heat and power (CHP) production planning under the deregulated power market. In CHP plants (units), generation of heat and power follows joint characteristics, which implies that it is difficult to determine the relative cost...... efficiency of the plants. We introduce in this paper the DRDP-RSC algorithm, which is a dynamic regrouping based dynamic programming (DP) algorithm based on linear relaxation of the ON/OFF states of the units, sequential commitment of units in small groups. Relaxed states of the plants are used to reduce...... the dimension of the UC problem and dynamic regrouping is used to improve the solution quality. Numerical results based on real-life data sets show that this algorithm is efficient and optimal or near-optimal solutions with very small optimality gap are obtained....

  16. An analytic solution of the transient behavior of backscattering thermal protective coatings exposed to combined radiative and convective heating

    Science.gov (United States)

    Cornelison, Charles J.; Howe, John T.

    1991-01-01

    An analytic solution of the material response to combined radiative and convective heating is presented. The solution includes the equations of radiative transfer (within the material), coupled to a transient energy equation which contains both radiative and convective terms. The analysis allows for unlimited spectral detail, but assumes that within the range of applicability, the various material properties do not vary significantly with temperature. Also, to facilitate development of the analytic solution, it is assumed that scattering within the material dominates absorption, and the material exposed surface does not ablate. The exposed surface boundary condition includes convective heating and spectral radiation, some of which is absorbed by the surface and some which penetrates the surface.

  17. Effect of sanitizer combined with steam heating on the inactivation of foodborne pathogens in a biofilm on stainless steel.

    Science.gov (United States)

    Ban, Ga-Hee; Kang, Dong-Hyun

    2016-05-01

    The combined effect of chemical sanitizers including sodium hypochlorite, hydrogen peroxide, iodophor, and benzalkonium chloride with steam heating on the inactivation of biofilms formed by Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on stainless steel was investigated. Six day old biofilms, comprised of a mixture of three strains each of three foodborne pathogens, were produced on stainless steel coupons at 25 °C and treated with each sanitizer alone (for 5, 15, and 30 s), steam alone (for 5, 10, and 20 s), and the combination. There was a synergistic effect of sanitizer and steam on the viability of biofilm cells of the three pathogens as evidenced by plating counts and imaging. The combination treatment achieved an additional 0.01 to 2.78 log reduction compared to the sum of each individual treatment. The most effective combination for reducing levels of biofilm cells was the combination of steam and iodophor; steam for 20 s and merely 20 ppm iodophor for 30 s reduced cell numbers to below the detection limit (combination treatment of sanitizer with steam can be applied to control foodborne pathogens biofilm cells in food processing facilities as a potential intervention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Combined Heat and Power Systems Technology Development and Demonstration 370 kW High Efficiency Microturbine

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-10-14

    The C370 Program was awarded in October 2010 with the ambitious goal of designing and testing the most electrically efficient recuperated microturbine engine at a rated power of less than 500 kW. The aggressive targets for electrical efficiency, emission regulatory compliance, and the estimated price point make the system state-of-the-art for microturbine engine systems. These goals will be met by designing a two stage microturbine engine identified as the low pressure spool and high pressure spool that are based on derivative hardware of Capstone’s current commercially available engines. The development and testing of the engine occurred in two phases. Phase I focused on developing a higher power and more efficient engine, that would become the low pressure spool which is based on Capstone’s C200 (200kW) engine architecture. Phase II integrated the low pressure spool created in Phase I with the high pressure spool, which is based on Capstone’s C65 (65 kW) commercially available engine. Integration of the engines, based on preliminary research, would allow the dual spool engine to provide electrical power in excess of 370 kW, with electrical efficiency approaching 42%. If both of these targets were met coupled with the overall CHP target of 85% total combined heating and electrical efficiency California Air Resources Board (CARB) level emissions, and a price target of $600 per kW, the system would represent a step change in the currently available commercial generation technology. Phase I of the C370 program required the development of the C370 low pressure spool. The goal was to increase the C200 engine power by a minimum of 25% — 250 kW — and efficiency from 32% to 37%. These increases in the C200 engine output were imperative to meet the power requirements of the engine when both spools were integrated. An additional benefit of designing and testing the C370 low pressure spool was the possibility of developing a stand-alone product for possible

  19. Combined Heat and Power Systems Technology Development and Demonstration 370 kW High Efficiency Microturbine

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-10-14

    The C370 Program was awarded in October 2010 with the ambitious goal of designing and testing the most electrically efficient recuperated microturbine engine at a rated power of less than 500 kW. The aggressive targets for electrical efficiency, emission regulatory compliance, and the estimated price point make the system state-of-the-art for microturbine engine systems. These goals will be met by designing a two stage microturbine engine identified as the low pressure spool and high pressure spool that are based on derivative hardware of Capstone’s current commercially available engines. The development and testing of the engine occurred in two phases. Phase I focused on developing a higher power and more efficient engine, that would become the low pressure spool which is based on Capstone’s C200 (200kW) engine architecture. Phase II integrated the low pressure spool created in Phase I with the high pressure spool, which is based on Capstone’s C65 (65 kW) commercially available engine. Integration of the engines, based on preliminary research, would allow the dual spool engine to provide electrical power in excess of 370 kW, with electrical efficiency approaching 42%. If both of these targets were met coupled with the overall CHP target of 85% total combined heating and electrical efficiency California Air Resources Board (CARB) level emissions, and a price target of $600 per kW, the system would represent a step change in the currently available commercial generation technology. Phase I of the C370 program required the development of the C370 low pressure spool. The goal was to increase the C200 engine power by a minimum of 25% — 250 kW — and efficiency from 32% to 37%. These increases in the C200 engine output were imperative to meet the power requirements of the engine when both spools were integrated. An additional benefit of designing and testing the C370 low pressure spool was the possibility of developing a stand-alone product for possible

  20. Effect of gemcitabine heat perfusion chemotherapy combined with carboplatin chemotherapy embolization on serum indexes in patients with hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Wei Zhou; Xing-Yuan Wang; Kun Zhou

    2015-01-01

    Objective:To study the effects of Gemcitabine heat perfusion chemotherapy combined with carboplatin chemotherapy embolization on serum indexes in patients with hepatocellular carcinoma.Methods:90 cases of hepatocellular carcinoma patients were enrolled and randomly divided into two groups. Observation group received gemcitabine heat perfusion chemotherapy combined with carboplatin chemotherapy embolization, control group received gemcitabine conventional perfusion chemotherapy combined with carboplatin chemotherapy embolization. Malignant biological indicators of serum and liver tissue apoptosis regulation of gene expression of the two groups were compared.Results: (1) Serum malignant biological indicators: serum DKK1, TK1, HIF-1 alpha mRNA and protein content of the observation group were lower than that of the control group; (2) Promoting apoptosis gene: MTS1 in liver tissue, Caspase 3 and Bax mRNA and protein contents of the observation group was higher than that of the control group; (3) Apoptosis suppressor genes: liver cancer tissues Plk1, Bcl - 2 and Survivn mRNA and protein contents of the observation group was higher than that of the control group.Conclusion:Gemcitabine hot perfusion chemotherapy plus carboplatin chemotherapy embolism helps to inhibit tumor biological behavior, induce liver cancer cells apoptosis, and it is an ideal treatment for primary liver cancer.

  1. Performance Improvement of Combined Cycle Power Plant Based on the Optimization of the Bottom Cycle and Heat Recuperation

    Institute of Scientific and Technical Information of China (English)

    Wenguo XIANG; Yingying CHEN

    2007-01-01

    Many F class gas turbine combined cycle (GTCC) power plants are built in China at present because of less emission and high efficiency. It is of great interest to investigate the efficiency improvement of GTCC plant. A combined cycle with three-pressure reheat heat recovery steam generator (HRSG) is selected for study in this paper.In order to maximize the GTCC efficiency, the optimization of the HRSG operating parameters is performed. The operating parameters are determined by means of a thermodynamic analysis, i.e. the minimization of exergy losses. The influence of HRSG inlet gas temperature on the steam bottoming cycle efficiency is discussed. The result shows that increasing the HRSG inlet temperature has less improvement to steam cycle efficiency when it is over 590℃. Partial gas to gas recuperation in the topping cycle is studied. Joining HRSG optimization with the use of gas to gas heat recuperation, the combined plant efficiency can rise up to 59.05% at base load. In addition,the part load performance of the GTCC power plant gets much better. The efficiency is increased by 2.11% at 75% load and by 4.17% at 50% load.

  2. Power contracting between two different partners. Biogas combined heat and power plants; Energie-Contracting zweier unterschiedlicher Partner. Biogas-Blockheizkraftwerk

    Energy Technology Data Exchange (ETDEWEB)

    Lennartz, Marc Wilhelm

    2013-06-15

    An agricultural consortium in the Eifel (Federal Republic of Germany) has adopted a comprehensive supply of a 7,000 m{sup 2} comprising hotel complex with combined heat and power. The old oil-fired central heating plant has been replaced by a biogas-powered combined heat and power plant (CHP). The hotel was directly connected to the CHP plant by means of a new, approximately 300 m long local heating network including buffer storage. Overall, the hotel operator saves approximately 300,000 L of heating oil annually. The energy demand of the hotel operator will be covered by more than 90 % by means of CHP plants. Thus 20 % of the heating costs is saved.

  3. Support schemes and ownership structures - The policy context for fuel cell based micro-combined heat and power

    Energy Technology Data Exchange (ETDEWEB)

    Ropenus, S.; Thorsten Schroeder, S.; Costa, A.; Obe, E.

    2010-05-15

    In recent years, fuel cell based micro-combined heat and power has received increasing attention due to its potential contribution to energy savings, efficiency gains, customer proximity and flexibility in operation and capacity size. The FC4Home project assesses technical and economic aspects of the ongoing fuel cell based micro-combined heat and power (mCHP) demonstration projects by addressing the socio-economic and systems analyses perspectives of a large-scale promotion scheme of fuel cells. This document constitutes the deliverable of Work Package 1 of the FC4Home project and provides an introduction to the policy context for mCHP. Section 1 describes the rationale for the promotion of mCHP by explaining its potential contribution to European energy policy goals. Section 2 addresses the policy context at the supranational European level by outlining relevant EU Directives on support schemes for promoting combined heat and power and energy from renewable sources. These Directives are to be implemented at the national level by the Member States. Section 3 conceptually presents the spectrum of national support schemes, ranging from investment support to market-based operational support. The choice of support scheme simultaneously affects risk and technological development, which is the focus of Section 4. Subsequent to this conceptual overview, Section 5 takes a glance at the national application of support schemes for mCHP in practice, notably in the three country cases of the FC4Home project, Denmark, France and Portugal. Another crucial aspect for the diffusion of the mCHP technology is possible ownership structures. These may range from full consumer ownership to ownership by utilities and energy service companies, which is discussed in Section 6. Finally, a conclusion (Section 7) wraps up previous findings and provides a short 'preview' of the quantitative analyses in subsequent Work Packages by giving some food for thought on the way. (author)

  4. Dual capillary tube / heat exchanger in combination with cycle priming for reducing charge migration

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Alberto Regio; Kuehl, Steven J.; Litch, Andrew D.; Wu, Guolian

    2017-07-04

    A refrigerator appliance including a multi-capacity compressor and a refrigerant circuit with two conduits and pressure reducing devices arranged in parallel between an evaporator and a condenser. Refrigerant can flow through one, both or none of the conduits and pressure reducing devices. The appliance also has a heat exchanger in contact with either one pressure reducing device, or one conduit between the pressure reducing device and the valve system. The appliance also includes a controller for priming the compressor above a nominal capacity for a predetermined or calculated duration at the beginning of an ON-cycle.

  5. Modeling of the combined heat exchanges in the ceramic firing kilns

    Energy Technology Data Exchange (ETDEWEB)

    El Hayek, M.; Lybaert, P.; Meunier, H. [Faculte Polytechnique de Mons (Belgium)

    1993-12-31

    A new methodology for the simulation of batch ceramic firing kilns is presented. A classical continuum approach is used in the free space and a quasi-continuum one in the load stacking area. This latter is replaced by an homogeneous porous medium with apparent equivalent characteristics. A flux model is used to take radiation heat transfer into account. The conduction in the load pieces is managed by the usual resistance scheme. The whole procedure is applied to a real refractory bricks firing kiln and shows promising features. (Authors). 8 refs., 4 figs.

  6. Combined coal gasification and Fe{sub 3}O{sub 4}-reduction using high-temperature solar process heat

    Energy Technology Data Exchange (ETDEWEB)

    Tamaura, Y. [Tokyo Inst. of Technology, Tokyo (Japan); Ehrensberger, K.; Steinfeld, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The coal/Fe{sub 3}O{sub 4} system was experimentally studied at PSI solar furnace. The reactants were directly exposed to a solar flux irradiation of 3,000 suns (1 sun = 1 kW/m{sup 2}). The combined gasification of coal and reduction of Fe{sub 2}O{sub 3} proceeded rapidly after only one second exposure, suggesting an efficient heat transfer and chemical conversion by direct solar energy absorption at the reaction site. The proposed solar thermochemical process offers the possibility of converting coal to a cleaner fluid fuel with a solar-upgraded calorific value. (author) 2 figs., 8 refs.

  7. Combined laser ultrasonics, laser heating, and Raman scattering in diamond anvil cell system

    Science.gov (United States)

    Zinin, Pavel V.; Prakapenka, Vitali B.; Burgess, Katherine; Odake, Shoko; Chigarev, Nikolay; Sharma, Shiv K.

    2016-12-01

    We developed a multi-functional in situ measurement system under high pressure equipped with a laser ultrasonics (LU) system, Raman device, and laser heating system (LU-LH) in a diamond anvil cell (DAC). The system consists of four components: (1) a LU-DAC system (probe and pump lasers, photodetector, and oscilloscope) and DAC; (2) a fiber laser, which is designed to allow precise control of the total power in the range from 2 to 100 W by changing the diode current, for heating samples; (3) a spectrometer for measuring the temperature of the sample (using black body radiation), fluorescence spectrum (spectrum of the ruby for pressure measurement), and Raman scattering measurements inside a DAC under high pressure and high temperature (HPHT) conditions; and (4) an optical system to focus laser beams on the sample and image it in the DAC. The system is unique and allows us to do the following: (a) measure the shear and longitudinal velocities of non-transparent materials under HPHT; (b) measure temperature in a DAC under HPHT conditions using Planck's law; (c) measure pressure in a DAC using a Raman signal; and (d) measure acoustical properties of small flat specimens removed from the DAC after HPHT treatment. In this report, we demonstrate that the LU-LH-DAC system allows measurements of velocities of the skimming waves in iron at 2580 K and 22 GPa.

  8. Combined laser ultrasonics, laser heating, and Raman scattering in diamond anvil cell system.

    Science.gov (United States)

    Zinin, Pavel V; Prakapenka, Vitali B; Burgess, Katherine; Odake, Shoko; Chigarev, Nikolay; Sharma, Shiv K

    2016-12-01

    We developed a multi-functional in situ measurement system under high pressure equipped with a laser ultrasonics (LU) system, Raman device, and laser heating system (LU-LH) in a diamond anvil cell (DAC). The system consists of four components: (1) a LU-DAC system (probe and pump lasers, photodetector, and oscilloscope) and DAC; (2) a fiber laser, which is designed to allow precise control of the total power in the range from 2 to 100 W by changing the diode current, for heating samples; (3) a spectrometer for measuring the temperature of the sample (using black body radiation), fluorescence spectrum (spectrum of the ruby for pressure measurement), and Raman scattering measurements inside a DAC under high pressure and high temperature (HPHT) conditions; and (4) an optical system to focus laser beams on the sample and image it in the DAC. The system is unique and allows us to do the following: (a) measure the shear and longitudinal velocities of non-transparent materials under HPHT; (b) measure temperature in a DAC under HPHT conditions using Planck's law; (c) measure pressure in a DAC using a Raman signal; and (d) measure acoustical properties of small flat specimens removed from the DAC after HPHT treatment. In this report, we demonstrate that the LU-LH-DAC system allows measurements of velocities of the skimming waves in iron at 2580 K and 22 GPa.

  9. Iridium double perovskite Sr2YIrO6 : A combined structural and specific heat study

    Science.gov (United States)

    Corredor, L. T.; Aslan-Cansever, G.; Sturza, M.; Manna, Kaustuv; Maljuk, A.; Gass, S.; Dey, T.; Wolter, A. U. B.; Kataeva, Olga; Zimmermann, A.; Geyer, M.; Blum, C. G. F.; Wurmehl, S.; Büchner, B.

    2017-02-01

    Recently, the iridate double perovskite Sr2YIrO6 has attracted considerable attention due to the report of unexpected magnetism in this Ir5 + (5 d4 ) material, in which according to the Jeff model, a nonmagnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba2 -xSrxYIrO6 no indication of magnetic transitions have been found. We present a structural, magnetic, and thermodynamic characterization of Sr2YIrO6 single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. As determined by x-ray diffraction, the Sr2YIrO6 single crystals have a cubic structure, with space group F m 3 ¯m . In agreement with the expected nonmagnetic ground state of Ir5 + (5d 4 ) in Sr2YIrO6 , no magnetic transition is observed down to 430 mK. Moreover, our results suggest that the low-temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of n ˜0.5 (2 )% . These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering.

  10. Separate and combined effects of dehydration and thirst sensation on exercise performance in the heat.

    Science.gov (United States)

    Cheung, S S; McGarr, G W; Mallette, M M; Wallace, P J; Watson, C L; Kim, I M; Greenway, M J

    2015-06-01

    Using intravenous infusion, we separated the physiologic consequences of 3% body mass dehydration from the conscious awareness of fluid replacement on time trial (TT) performance in the heat. Eleven trained cyclists performed 90 min of steady-state (50% V ˙ O 2 peak ) cycling followed by a self-paced 20-km TT in a hot-dry (35 °C, 10% relative humidity, wind speed 3.0 m/s) environment while euhydrated-not thirsty (EU-NT), euhydrated-thirsty (EU-T), dehydrated-not thirsty (DH-NT), or dehydrated-thirsty (DH-T). Thirst was manipulated by providing (NT) or withholding (T) ad libitum 35 °C water oral rinse. Distinct hydration states existed, with 0.4 ± 0.5% dehydration following the 20-km TT (EU) compared with 3.2 ± 0.6% in DH (P performance in the heat for a healthy and fit population.

  11. An improved unit decommitment algorithm for combined heat and power systems

    DEFF Research Database (Denmark)

    Rong, Aiying; Lahdelma, R.; Grunow, Martin

    2009-01-01

    heat and power must be done in coordination. We present an improved unit decommitment (IUD) algorithm that starts with an improved initial solution with less heat surplus so that the relative cost-efficiency of the plants can be determined more accurately. Then the subsequent decommitment procedures...... and a linear relaxation of the ON/OFF states of the plants. We compare the IUD algorithm with realistic test data against a generic unit decommitment (UD) algorithm. Numerical results show that IUD is an overall improvement of UD. The solution quality of IUD is better than that of UD for almost all of tested...... cases. The maximum improvement is 11.3% and the maximum degradation is only 0.04% (only two sub-cases out of 216 sub-cases) with an average improvement of 0.3-0.5%, for different planning horizons. Moreover, IUD is more efficient (1.1-3 times faster on average) than UD. (C) 2008 Elsevier B.V. All rights...

  12. EPA Honors 2015 Energy Star Combined Heat and Power Winners / Facilities in Maine, N.J., Texas recognized for emission reductions

    Science.gov (United States)

    WASHINGTON - The U.S. Environmental Protection Agency (EPA) is recognizing three facilities with the Energy Star Combined Heat and Power (CHP) Award for superior performance of their CHP systems. High-efficiency CHP technology reduces emissions of c

  13. First results of ion cyclotron resonance heating on ASDEX upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Noterdaeme, J.; Hoffmann, C.; Brambilla, M.; Buechl, K.; Eberhagen, A.; Field, A.; Fuchs, C.; Gehre, O.; Gernhardt, J.; Gruber, O.; Haas, G.; Hermann, A.; Hofmeister, F.; Kallenbach, A.; Lieder, G.; Mertens, V.; Murmann, H.; de Pena Hempel, S.; Poschenrieder, W.; Richter, T.; Ryter, F.; Salmon, N.; Salzmann, H.; Schneider, W.; Wesner, F.; Zehrfeld, H.; Zohm, H. (Max-Planck-Institute for Plasmaphysics, D-8046 Garching (Germany)); ASDEX Upgrade Team

    1994-10-15

    ASDEX Upgrade is equipped with an ICRH system consisting of 4 generators of 2 MW power each and 4 double loop antennas. The generators, tuneable in frequency from 30 to 120 MHz, cover several heating scenarios over a wide range of magnetic fields (1 T[lt]B[sub t][lt]3.9 T): minority heating of H and He[sub 3] and second harmonic heating of H and D. ICRH-heated discharges in ASDEX Upgrade were so far carried out mainly at 30 MHz and a magnetic field of 2 T (H minority in D and He). Peak powers of 2.4 MW and pulse length up to 2.5 s were achieved (total energy 3.75 MJ). In L-mode, the density on turn-on of the ICRH stays constant, or even decreases. The ratio of radiated power to total input power is unchanged (60% in an unboronized machine, 30% in a freshly boronized machine) between Ohmic and ICRH phases. The electron temperature increases with 0.9 MW from 1 to 1.25 keV, the loop voltage drops. Transitions to the H-mode were easily and reliably achieved with ICRH alone (necessary ICRH power as low as 0.9 MW) and the length of the ELMy H-mode phases was limited only by the applied ICRH pulse length (ELMy H-mode phases of up to 2 s were achieved). The paper presents further results on heating and confinement in L and H-mode, antenna and edge studies and on divertor measurements. Preliminary experiments, performed with a combination of H minority heating (30 MHz) and H second harmonic (60 MHz) in 600 kA He and D discharges (H minority in the 5 to 20% range) at 2 T, and with non-resonant heating (30 MHz and 60 MHz at 1.35 T) are briefly discussed.

  14. Decentralized combined heat and power production by two-stage biomass gasification and solid oxide fuel cells

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud; Elmegaard, Brian

    2013-01-01

    To investigate options for increasing the electrical efficiency of decentralized combined heat and power (CHP) plants fuelled with biomass compared to conventional technology, this research explored the performance of an alternative plant design based on thermal biomass gasification and solid oxide...... fuel cells (SOFC). Based on experimental data from a demonstrated 0.6 MWth two-stage gasifier, a model of the gasifier plant was developed and calibrated. Similarly, an SOFC model was developed using published experimental data. Simulation of a 3 MWth plant combining two-stage biomass gasification......, carbon conversion factor in the gasifier and the efficiency of the DC/AC inverter were the most influential parameters in the model. Thus, a detailed study of the practical values of these parameters was conducted to determine the performance of the plant with the lowest possible uncertainty. The SOFC...

  15. Fuel cell based micro-combined heat and power under different policy frameworks - An economic analysis

    DEFF Research Database (Denmark)

    Hansen, Lise-Lotte Pade; Schröder, Sascha Thorsten

    2013-01-01

    political objectives on the design of the future energy system. This article takes the point of departure in the existing support schemes, most common ownership structures, energy prices, electricity demand and heating demand in Denmark, France and Portugal. For the three countries, we analyse different...... constellations of operational strategies, ownership structures and promotion schemes and assess the necessary support levels for residential fuel cells under these constellations. We find that the necessary support levels are not excessively high compared to the initial support levels for e.g. photovoltaic...... systems in Germany. Especially net metering in Denmark and price premiums for fuel cells functioning as a virtual power plant in France and Portugal seems promising. The annual number of operation hours depends strongly on the operational scheme. For thermal-led units, cold start and modulation capacity...

  16. Expert Meeting Report. Recommendations for Applying Water Heaters in Combination Space and Domestic Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A. [Building Science Corporation (BSC), Somerville, MA (United States); Ueno, K. [Building Science Corporation (BSC), Somerville, MA (United States); Bergey, D. [Building Science Corporation (BSC), Somerville, MA (United States); Osser, R. [Building Science Corporation (BSC), Somerville, MA (United States)

    2012-06-01

    This Building America expert meeting was held on 7/31/2011, in Westford, Massachusetts. Presentations and discussions centered on the design, performance, and maintenance of these combination systems, with the goal of developing foundational information toward the development of a Building America Measure Guideline on this topic.

  17. Anti-HBV efficacy of combined siRNAs targeting viral gene and heat shock cognate 70

    Directory of Open Access Journals (Sweden)

    Bian Zhongqi

    2012-11-01

    Full Text Available Abstract Background Hepatitis B virus (HBV infection is a major health concern with more than two billion individuals currently infected worldwide. Because of the limited effectiveness of existing vaccines and drugs, development of novel antiviral strategies is urgently needed. Heat stress cognate 70 (Hsc70 is an ATP-binding protein of the heat stress protein 70 family. Hsc70 has been found to be required for HBV DNA replication. Here we report, for the first time, that combined siRNAs targeting viral gene and siHsc70 are highly effective in suppressing ongoing HBV expression and replication. Methods We constructed two plasmids (S1 and S2 expressing short hairpin RNAs (shRNAs targeting surface open reading frame of HBV(HBVS and one plasmid expressing shRNA targeting Hsc70 (siHsc70, and we used the EGFP-specific siRNA plasmid (siEGFP as we had previously described. First, we evaluated the gene-silencing efficacy of both shRNAs using an enhanced green fluorescent protein (EGFP reporter system and flow cytometry in HEK293 and T98G cells. Then, the antiviral potencies of HBV-specific siRNA (siHBV in combination with siHsc70 in HepG2.2.15 cells were investigated. Moreover, type I IFN and TNF-α induction were measured by quantitative real-time PCR and ELISA. Results Cotransfection of either S1 or S2 with an EGFP plasmid produced an 80%–90% reduction in EGFP signal relative to the control. This combinational RNAi effectively and specifically inhibited HBV protein, mRNA and HBV DNA, resulting in up to a 3.36 log10 reduction in HBV load in the HepG2.2.15 cell culture supernatants. The combined siRNAs were more potent than siHBV or siHsc70 used separately, and this approach can enhance potency in suppressing ongoing viral gene expression and replication in HepG2.2.15 cells while forestalling escape by mutant HBV. The antiviral synergy of siHBV used in combination with siHsc70 produced no cytotoxicity and induced no production of IFN-α, IFN-β and TNF

  18. An engineering-economic analysis of combined heat and power technologies in a (mu)grid application

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Owen; Ouaglal, Boubekeur; Bartholomew, Emily; Marnay, Chris; Bourassa, Norman

    2002-03-01

    This report describes an investigation at Ernesto Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) of the potential for coupling combined heat and power (CHP) with on-site electricity generation to provide power and heating, and cooling services to customers. This research into distributed energy resources (DER) builds on the concept of the microgrid (mGrid), a semiautonomous grouping of power-generating sources that are placed and operated by and for the benefit of its members. For this investigation, a hypothetical small shopping mall (''Microgrid Oaks'') was developed and analyzed for the cost effectiveness of installing CHP to provide the mGrid's energy needs. A mGrid consists of groups of customers pooling energy loads and installing a combination of generation resources that meets the particular mGrid's goals. This study assumes the mGrid is seeking to minimize energy costs. mGrids could operate independently of the macrogrid (the wider power network), but they are usually assumed to be connected, through power electronics, to the macrogrid. The mGrid in this study is assumed to be interconnected to the macrogrid, and can purchase some energy and ancillary services from utility providers.

  19. The combined effect of nisin, moderate heating and high hydrostatic pressure on the inactivation of Bacillus sporothermodurans spores.

    Science.gov (United States)

    Aouadhi, C; Simonin, H; Mejri, S; Maaroufi, A

    2013-07-01

    To investigate the combined effect of hydrostatic pressure (HP), moderate temperature and nisin on the inactivation of Bacillus sporothermodurans spores which are known to be contaminant of dairy products and to be extremely heat-resistant. A central composite experimental design with three factors, using response surface methodology, was used. By analysing the response surfaces and their corresponding contour plots, an interesting interaction with the three factors was observed. The inactivation observed was shown to be well fitted with values predicted by the quadratic equation, since the adjusted determination coefficient (R(adj)(2)) was 0·979. The optimum process parameters for a 5-log spores ml(-1) reduction of B. sporothermodurans spores were obtained, 472 MPa/53°C for 5 min in presence of 121 UI ml(-1) of nisin. Nisin and temperature treatments improve the effectiveness of pressure in the inactivation of highly heat-resistant spores of B. sporothermodurans. This study shows the potential of using high HP for a short time (5 min) in combination with moderate temperature and nisin to inactivate B. sporothermodurans spores in milk. Such treatments could be applied by the dairy industry to ensure the commercial sterility of UHT milk. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

  20. Performance analysis of a bio-gasification based combined cycle power plant employing indirectly heated humid air turbine

    Science.gov (United States)

    Mukherjee, S.; Mondal, P.; Ghosh, S.

    2016-07-01

    Rapid depletion of fossil fuel has forced mankind to look into alternative fuel resources. In this context, biomass based power generation employing gas turbine appears to be a popular choice. Bio-gasification based combined cycle provides a feasible solution as far as grid-independent power generation is concerned for rural electrification projects. Indirectly heated gas turbine cycles are promising alternatives as they avoid downstream gas cleaning systems. Advanced thermodynamic cycles have become an interesting area of study to improve plant efficiency. Water injected system is one of the most attractive options in this field of applications. This paper presents a theoretical model of a biomass gasification based combined cycle that employs an indirectly heated humid air turbine (HAT) in the topping cycle. Maximum overall electrical efficiency is found to be around 41%. Gas turbine specific air consumption by mass is minimum when pressure ratio is 6. The study reveals that, incorporation of the humidification process helps to improve the overall performance of the plant.

  1. Synergistic skin heat shock protein expression in response to combined laser treatment with a diode laser and ablative fractional lasers.

    Science.gov (United States)

    Paasch, Uwe; Sonja, Grunewald; Haedersdal, Merete

    2014-06-01

    Diode laser-based skin heating has been shown to minimise scars by interfering with wound healing responses through the induction of heat shock proteins (HSP). HSP are also induced after ablative fractional laser (AFXL) wound healing. AFXL itself is highly recommended for scar treatment. Therefore, the sequential combination of both modalities may produce superior outcomes. The aim of this study was to examine the pretreatment effects of a diode laser before AFXL on wound healing responses in terms of HSP up-regulation in an in vitro model. Immediate responses and responses on days 1, 3 or 6 post-procedure were studied in an in vitro porcine skin model (n = 240). Untreated samples served as control. Immunohistochemical investigation (Hsp70) was performed in all untreated controls, diode laser-, AFXL-, and in diode laser + AFXL-treated samples. Hsp70 was shown to be up-regulated by all interventions between days 1 and 6 after interventions. The largest effect was caused by the combination of a diode laser and an AFXL procedure. Diode laser exposure induces a skin HSP response that can be further enhanced by sequential AFXL treatment. Clinical studies are necessary to investigate the dose response of HSP on scar formation and refine suitable laser exposure settings.

  2. Swiss energy research program on heat-pumps, combined heat and power and refrigeration for 2008-2011; Energieforschungsprogramm. Waermepumpen, Waerme-Kraft-Kopplung, Kaelte fuer die Jahre 2008-2011

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, T. [Hochschule fuer Technik HSR, Rapperswil (Switzerland); Eckmanns, A. [Swiss Federal Office of Energy (OFEN), Berne (Switzerland)

    2009-07-15

    This report published by the Swiss Federal Office of Energy (SFOE) takes a look at the research programme on heat-pumps, combined heat and power and refrigeration for the years 2008 - 2011. Work proposed for the years 2008 - 2011 involves the following topics: Improvement of components and the thermodynamic cycles of heat pumps and refrigeration plants as well as the improvements in the efficiency of cogeneration plants and the reduction of emission of pollutants. Also, the overall optimisation of total systems is to be examined. Highly-efficient systems for sanitary hot water production are to be looked at, as are miniaturisation and new solutions for the installation of heating and cooling systems with heat pumps. Also the development of environmental-friendly working fluids for heat pumps and refrigeration plants is planned. Pilot and demonstration projects are also to be supported in all areas.

  3. Multilevel converters for 10 MW Wind Turbines

    DEFF Research Database (Denmark)

    Ma, Ke; Blaabjerg, Frede

    2011-01-01

    Several promising multi-level converter configurations for 10 MW Wind Turbines both with direct drive and one-stage gear box drive using Permanent Magnet Synchronous Generator (PMSG) are proposed, designed and compared. Reliability is a crucial indicator for large scale wind power converters...

  4. Sudurnes Regional Heating Corp.

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J. [ed.

    1996-11-01

    The Svartsengi geothermal area is close to the town of Grindavik on the Rekjanes peninsula and is part of an active fissure swarm, lined with crater-rows and open fissures and faults. The high-temperature area has an area of 2 sq. km and shows only limited signs of geothermal activity at the surface. The reservoir, however, contains lots of energy and at least 8 wells supply the Svartsengi Power Plant with steam. The steam is not useable for domestic heating purposes so that heat exchangers are used to heat cold groundwater with the steam. Some steam is also used for producing 16.4 MW{sub e} of electrical power. The article shows the distribution system piping hot water to nine towns and the Keflavik International Airport. The effluent brine from the Svartsengi Plant is disposed of into a surface pond, called the Blue Lagoon, popular to tourists and people suffering from psoriasis and other forms of eczema seeking therapeutic effects from the silica rich brine. This combined power plant and regional district heating system (cogeneration) is an interesting and unique design for the application of geothermal energy.

  5. Effect of the Combined Heat Treatment and Severe Plastc Deformation on the Microstructure of Cunisi Alloy

    OpenAIRE

    Głuchowski W.; Rdzawski Z.; Sobota J.; Domagała-Dubiel J.

    2016-01-01

    The aim of this work was to study the microstructure and functional properties of CuNi2Si1 alloy. The material was prepared classically by melting, casting, hot rolling and cold rolling. The obtained strips were processed with combined operations of supersaturation, ageing and one of the intensive deformation method - repetitive corrugation and straightening. The efficiency of RCS operation in shaping of functional properties in precipitation hardened copper alloys depends not only on tool ge...

  6. Design of an aeroelastically tailored 10 MW wind turbine rotor

    DEFF Research Database (Denmark)

    Zahle, Frederik; Tibaldi, Carlo; Pavese, Christian;

    2016-01-01

    This work presents an integrated multidisciplinary wind turbine optimization framework utilizing state-of-the-art aeroelastic and structural tools, capable of simultaneous design of the outer geometry and internal structure of the blade. The framework is utilized to design a 10 MW rotor constrained...... not to exceed the design loads of an existing reference wind turbine. The results show that through combined geometric tailoring of the internal structure and aerodynamic shape of the blade it is possible to achieve significant passive load alleviation that allows for a 9% longer blade with an increase in AEP...

  7. Design Tool for 5-20 MW Direct Drive Generators

    DEFF Research Database (Denmark)

    Leban, Krisztina Monika; Ritchie, Ewen; Argeseanu, Alin

    2014-01-01

    for the application is presented. Assessment is made based on suitability criteria combined with the SWOT analysis method. An analytic design is generated at first; then visualised in 3D CAD, evaluated using FEM and a dynamic model simulation. An optimisation module is available for improving the design......This paper reports on a machine design tool for large (5-10MW) direct drive electrical generator. The aim of the work is to construct a flexible calculation tool that enables the analysis of different ideas and concepts for generator design. The tool is intended for engineers that are involved...

  8. Combined bio and solar heating system. Handbook for system design; Kombinerade bio- och solvaermesystem. Handbok foer systemutformning

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Tomas

    2008-11-15

    The purpose of this report is to compile the knowledge available concerning combined pellets and solar system in order to support companies in their systems design. This publication deals with experience gained in research on solar and pellet heating, and gives proposals to system design, various technical solutions, and how systems should be controlled. When solar and pellets are combined, there are many possibilities to interconnect the systems. There are different traditions in different countries, which makes the system solutions vary from country to country. A general conclusion is that conventional Swedish boilers with built-in hot water heater are not appropriate for conventional solar systems. It gives rise to complex solutions and it is difficult to achieve good stratification in the water tank. In a solar system, it is important that the tank can be discharged in such a way that sharp stratification is obtained. This means that the tank bottom must be chilled to the temperature of incoming cold water and that the middle part must be cooled to the same temperature as the radiator return. If solar panels even in winter can work to preheat the cold water of 10 to 20 C, a much better efficiency is obtained on collectors than if the radiator return must be preheated, which at best is at a temperature level of between 30 and 40 C. To this end, the radiator return is placed well up from the bottom of the tank and the tap water is preheated in a loop that starts in the tank bottom. Another important parameter in the tank design is that heat losses are kept low, it is important that the solar heat can produce the hot water even during overcast periods in summer and to keep energy consumption low. In modern houses where the tank is placed in the living area, it is important to avoid high temperatures in the room where the tank is placed. To obtain a good isolation one must ensure that there is an airtight layer across the isolation that also closes tightly against

  9. Combined heat shock protein 90 and ribosomal RNA sequence phylogeny supports multiple replacements of dinoflagellate plastids.

    Science.gov (United States)

    Shalchian-Tabrizi, Kamran; Minge, Marianne A; Cavalier-Smith, Tom; Nedreklepp, Joachim M; Klaveness, Dag; Jakobsen, Kjetill S

    2006-01-01

    Dinoflagellates harbour diverse plastids obtained from several algal groups, including haptophytes, diatoms, cryptophytes, and prasinophytes. Their major plastid type with the accessory pigment peridinin is found in the vast majority of photosynthetic species. Some species of dinoflagellates have other aberrantly pigmented plastids. We sequenced the nuclear small subunit (SSU) ribosomal RNA (rRNA) gene of the "green" dinoflagellate Gymnodinium chlorophorum and show that it is sister to Lepidodinium viride, indicating that their common ancestor obtained the prasinophyte (or other green alga) plastid in one event. As the placement of dinoflagellate species that acquired green algal or haptophyte plastids is unclear from small and large subunit (LSU) rRNA trees, we tested the usefulness of the heat shock protein (Hsp) 90 gene for dinoflagellate phylogeny by sequencing it from four species with aberrant plastids (G. chlorophorum, Karlodinium micrum, Karenia brevis, and Karenia mikimotoi) plus Alexandrium tamarense, and constructing phylogenetic trees for Hsp90 and rRNAs, separately and together. Analyses of the Hsp90 and concatenated data suggest an ancestral origin of the peridinin-containing plastid, and two independent replacements of the peridinin plastid soon after the early radiation of the dinoflagellates. Thus, the Hsp90 gene seems to be a promising phylogenetic marker for dinoflagellate phylogeny.

  10. CHP: Combined Heat and Power: a vision of energy efficiency; Cogeracao: uma visao de eficiencia energetica

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Osvaldo A.S.N. de; Abreu, Melissa E. de; Marcal, Roberto L.; Ferreira, Ademilson D.; Ferreira, Patricia E.; Monterio, Glauber J.R.; Silva, Ademir B. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The installation of a cogeneration plant has been the subject of discussions on alternatives in the Brazilian energy matrix. Considered viable solution in the not too distant past, 2001, when Brazil was undergoing a process of the economic slowdown, lack of investments in the energy sector, unemployment and reaching the peak of the crisis with the rationing of electricity. The principle of the cogeneration system is designed primarily to meet electrical demand, so there is no surplus production of energy and do not need to buy with the concessionaire, except in cases of the system stops on account of maintenance. However, there is a recovery of waste heat produced in thermodynamic processes for generation of electricity within a model that 'conventional' would be wasted. In this case, the exploitation can be given in the form of steam, hot water and/or cold, for secondary application, or can not be linked to a process. Based on the results of the fieldwork, aims to show that, despite the limitations inherent in the process of cogeneration, is justified economically the installation of this system in relation to the growth of procedures developed in CENPES and its resident effective. (author)

  11. Flexible Furnace Concepts for Vacuum Heat Treatment Combined with High-pressure Gas Quenching

    Institute of Scientific and Technical Information of China (English)

    Karl Ritter; Stefan Wiebach

    2004-01-01

    IN the past five years the process combination of vacuum hardening, respectively vacuum carburizing with high-pressure gas quenching was successfully introduced to the market, especially in the manufacture of gears. In the meantime furnace concepts for various applications are available to the industry. In the following report three plant varieties are introduced, which differ in process flexibility and throughput. This report also explains criteria for the selection of a furnace in view of the existing application requirements. Besides this a short introduction is given into the vacuum carburizing process and the high-pressure gas quenching technology.

  12. MATERIAL PARAMETER OF RUBBER GLOVE VULCANIZED USING COMBINED INFRARED AND HOT-AIR HEATING

    Directory of Open Access Journals (Sweden)

    Tipapon Khamdaeng

    2014-01-01

    Full Text Available Vulcanization is an important chemical-thermal process in production of rubber products resulting in change of material properties, increased elasticity and strength. In general, Young’s modulus is used as an indicator of elastic deformation at loading configuration. However, rubber is not truly elastic and a single parameter is insufficient to describe the whole deformation contributed by microstructure of rubber network. Therefore, we present the material parameters concerning the mechanical interaction of rubber constituents. In this study, tensile force and elongation were measured to analyze the rubber deformation. In order to describe the deformation behavior of the combined infrared and hot-air vulcanized rubber glove, the material properties, stress and stretch, were therefore presented. The stress-stretch relationships of the vulcanized rubber gloves were established based on previously well-known hyperelastic material model and their material parameters were determined using a parameter estimation technique. In conclusion, the stress-stretch relationships of the combined infrared and hot-air vulcanized rubber glove can be successfully established with our optimized material parameters; the magnitudes of rubber modulus (CR and locking stretch (λL were in a range of 0.041-0.079 MPa and 10.27-70.12, respectively. Furthermore, the resulting material parameters can be properly used to indicate the micro structural deformation.

  13. Optimum power yield for bio fuel fired combined heat and power plants

    Energy Technology Data Exchange (ETDEWEB)

    Broden, Henrik; Nystroem, Olle; Joensson, Mikael

    2012-05-15

    Plant owners, suppliers, research institutions, industry representatives and (supporting) authorities are continuing to question the viability of what can be expected by increasing the steam data and the efficiency of cogeneration plants. In recent years, the overall conditions for investment in CHP have changed. Today, there is access to new materials that allow for more advanced steam data while maintaining availability. Although the financial environment with rising prices of electricity, heating and fuel along with the introduction of energy certificates and the interest in broadening the base of fuel has changed the situation. At the same time as the increased interest in renewable energy production creates competition among energy enterprises to find suppliers, increased prices for materials and labor costs have also resulted in increased investment and maintenance costs. Research on advanced steam data for biomass-fired power cogeneration plants has mainly emphasized on technical aspects of material selection and corrosion mechanisms based on performance at 100 % load looking at single years. Reporting has rarely been dealing with the overall economic perspective based on profitability of the CHP installations throughout their entire depreciation period. In the present report studies have been performed on how the choice of steam data affects the performance and economy in biomass-fired cogeneration plants with boilers of drum type and capacities at 30, 80 and 160 MWth with varied steam data and different feed water system configurations. Profitability is assessed on the basis of internal rate of return (IRR) throughout the amortization period of the plants. In addition, sensitivity analyses based on the most essential parameters have been carried out. The target group for the project is plant owners, contractors, research institutions, industry representatives, (supporting) authorities and others who are faced with concerns regarding the viability of what

  14. A Two Frequency 1.5 MW Gyrotron Experiment

    Science.gov (United States)

    Tax, David; Guss, William; Shapiro, Michael; Temkin, Richard; Rock, Ben; Vernon, Ronald; Neilson, Jeffrey

    2012-10-01

    Megawatt gyrotrons are an important microwave source for electron cyclotron heating and current drive (ECH/ECCD) in fusion plasmas due to their ability to produce megawatts of power at millimeter wave frequencies. The MIT gyrotron operates nominally at 96 kV and 40 A with 3 μs pulses and has previously demonstrated 1.5 MW of output power with > 50 % efficiency at 110 GHz with a depressed collector. A new cavity has been designed for 1.5 MW operation at two distinct frequencies: 110 GHz in the TE22,6 mode and 124.5 GHz in the TE24,7 mode. A new internal mode converter (IMC) consisting of a dimpled wall launcher and four smooth curved mirrors has also been designed and was optimized for both modes. Simulations of the IMC indicate that > 98 % Gaussian beam content could be achieved for each mode. Cold test results for the components will be presented as well as the current status of the hot test experiment.

  15. Case Study: Fuel Cells Provide Combined Heat and Power at Verizon's Garden City Central Office

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-12-01

    This case study describes how Verizon's Central Office in Garden City, NY, installed a 1.4-MW phosphoric acid fuel cell system as an alternative solution to bolster electric reliability, optimize the company's energy use, and reduce costs in an environmentally responsible manner.

  16. Effect of the Combined Heat Treatment and Severe Plastc Deformation on the Microstructure of Cunisi Alloy

    Directory of Open Access Journals (Sweden)

    Głuchowski W.

    2016-06-01

    Full Text Available The aim of this work was to study the microstructure and functional properties of CuNi2Si1 alloy. The material was prepared classically by melting, casting, hot rolling and cold rolling. The obtained strips were processed with combined operations of supersaturation, ageing and one of the intensive deformation method - repetitive corrugation and straightening. The efficiency of RCS operation in shaping of functional properties in precipitation hardened copper alloys depends not only on tool geometry and operating parameters but also on whether and at what stage of strip production the supersaturation operation was applied. Application of the supersaturation before RCS operation broadens the potential to shape the set of functional properties. Comparable functional properties of the precipitation hardened copper alloy strips can be reached without application of the supersaturation operation in their manufacturing processes. The process of RCS applied after annealing, and the potentially slightly lower mechanical properties would be compensated by higher electrical conductivity.

  17. Combination of two oxidant stressors suppresses the oxidative stress and enhances the heat shock protein 27 response in healthy humans.

    Science.gov (United States)

    Brerro-Saby, Christelle; Delliaux, Stephane; Steinberg, Jean Guillaume; Boussuges, Alain; Gole, Yoann; Jammes, Yves

    2010-06-01

    We tested the hypothesis that the combination of 2 oxidant stressors (hyperoxia and fatiguing exercise) might reduce or suppress the oxidative stress. We concomitantly measured the plasma concentration of heat shock proteins (Hsp) that protect the cells against the deleterious effects of reactive oxygen species. Healthy humans breathed pure oxygen under normobaric condition for 50-minute periods during which they stayed at rest or executed maximal static handgrip sustained until exhaustion. They also repeated handgrip bouts in normoxic condition. We performed venous blood measurements of 2 markers of the oxidative stress (thiobarbituric acid reactive substances and reduced ascorbic acid) and Hsp27. Under normoxic condition, the handgrip elicited an oxidative stress and a modest increase in plasma Hsp27 level (+7.1 +/- 5.4 ng/mL). Under hyperoxic condition, (1) at rest, compared with the same time schedule in normoxic condition, we measured an oxidative stress (increased thiobarbituric acid reactive substances and decreased reduced ascorbic acid levels) and the plasma Hsp27 level increased (maximal variation, +12.5 +/- 6.0 ng/mL); and (2) after the handgrip, the oxidative stress rapidly disappeared. The combination of both hyperoxia and handgrip bout doubled the Hsp27 response (maximal variation, +24.8 +/- 9.2 ng/mL). Thus, the combination of 2 hits eliciting an oxidative stress seems to induce an adaptive Hsp27 response that might counterbalance an excessive production of reactive oxygen species. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Volume, heat, and freshwater fluxes towards the Arctic from combined altimetry and hydrography in the Norwegian Sea

    Directory of Open Access Journals (Sweden)

    K. A. Mork

    2009-10-01

    Full Text Available The Norwegian Atlantic Current (NwAC is the main part of Atlantic water (AW towards the Arctic. Fluxes of volume, heat and freshwater in the NwAC are estimated for the period 1992–2007 by combining data from a repeated hydrographic transect in the Norwegian Sea with a recently available data set of absolute topography. The analysis shows a two-branch structure of the NwAC in the section, and the calculated absolute velocities are basically in accordance with independent current measurements. Compared with previous estimated fluxes of volume and heat the estimates in the eastern branch (3.7 Sv/118 TW, Sv=106 m3 s−1, TW=1012 W are comparable, the estimates for the western branch (1.4 Sv/39 TW are lower, partly because of a region with recirculation that previously has been neglected. The total fluxes are lower than the upstream fluxes, but several processes, which are addressed, make the upstream-downstream comparison problematic. The heat flux has positive trend of 4.7 TW yr−1 and the freshwater flux has negative trend of −2.4 m Sv yr−1. The trends are results of both increased volume flux (0.13 Sv yr−1 and warmer and saltier inflowing AW. The wind stress curl, spatially averaged over the Norwegian Basin, is on inter-annual scale correlated with both the total fluxes and the occupied area of AW in the section. The latter is influenced by upstream changes in the North Atlantic subpolar gyre on longer time-scale. A first exploitation of the results suggests that increased Atlantic inflow leads to decreased upper ocean stability and delayed phytoplankton spring bloom in the Norwegian Sea, one year later.

  19. Simulation of a combined space and water heating system firing pellet fuel for commercial/residential application

    Energy Technology Data Exchange (ETDEWEB)

    Clements, B.R.; Pearson, B.; Hayden, A.C.S. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

    2001-06-01

    Gensym Corporation has developed a real-time dynamic simulator which can test different physical configurations of a variety of commercial or residential combined space heating and domestic hot water systems. This simulator was originally designed to test biomass pellet-fueled stoves, but it can also be applied to more conventional gas and oil fired systems. Each physical configuration can be tested under different operating conditions to determine optimal system design for each unique situation. CANMET Energy Technology Centre is focused on developing advanced residential integrated systems using biomass pellets as a fuel to take advantage of their energy efficiency and the environmental benefits that they offer. High efficiency pellet-fired integrated home energy systems consist of components that can be configured in several ways to suit specific installation needs. The major components of the system are the fuel storage and supply system, the pellet burner, the fuel and ash removal system, the furnace air supply, the exhaust module, boiler, hot water storage tank, forced air fan coil unit and the plate to plate domestic hot water heat exchanger. Many different design and control scenarios were tested using the real-time simulator before developing an optimal arrangement for a specific set of constraints. The simulator proved to be an extremely valuable tool in developing and testing control strategies. 4 refs., 3 figs.

  20. Comparison of Technological Options for Distributed Generation-Combined Heat and Power in Rajasthan State of India

    Directory of Open Access Journals (Sweden)

    Ram Kumar Agrawal

    2013-01-01

    Full Text Available Distributed generation (DG of electricity is expected to become more important in the future electricity generation system. This paper reviews the different technological options available for DG. DG offers a number of potential benefits. The ability to use the waste heat from fuel-operated DG, known as combined heat and power (CHP, offers both reduced costs and significant reductions of CO2 emissions. The overall efficiency of DG-CHP system can approach 90 percent, a significant improvement over the 30 to 35 percent electric grid efficiency and 50 to 90 percent industrial boiler efficiency when separate production is used. The costs of generation of electricity from six key DG-CHP technologies; gas engines, diesel engines, biodiesel CI engines, microturbines, gas turbines, and fuel cells, are calculated. The cost of generation is dependent on the load factor and the discount rate. It is found that annualized life cycle cost (ALCC of the DG-CHP technologies is approximately half that of the DG technologies without CHP. Considering the ALCC of different DG-CHP technologies, the gas I.C. engine CHP is the most effective for most of the cases but biodiesel CI engine CHP seems to be a promising DG-CHP technology in near future for Rajasthan state due to renewable nature of the fuel.

  1. Electricity and combined heat and power from municipal solid waste; theoretically optimal investment decision time and emissions trading implications.

    Science.gov (United States)

    Tolis, Athanasios; Rentizelas, Athanasios; Aravossis, Konstantin; Tatsiopoulos, Ilias

    2010-11-01

    Waste management has become a great social concern for modern societies. Landfill emissions have been identified among the major contributors of global warming and climate changes with significant impact in national economies. The energy industry constitutes an additional greenhouse gas emitter, while at the same time it is characterized by significant costs and uncertain fuel prices. The above implications have triggered different policies and measures worldwide to address the management of municipal solid wastes on the one hand and the impacts from energy production on the other. Emerging methods of energy recovery from waste may address both concerns simultaneously. In this work a comparative study of co-generation investments based on municipal solid waste is presented, focusing on the evolution of their economical performance over time. A real-options algorithm has been adopted investigating different options of energy recovery from waste: incineration, gasification and landfill biogas exploitation. The financial contributors are identified and the impact of greenhouse gas trading is analysed in terms of financial yields, considering landfilling as the baseline scenario. The results indicate an advantage of combined heat and power over solely electricity production. Gasification, has failed in some European installations. Incineration on the other hand, proves to be more attractive than the competing alternatives, mainly due to its higher power production efficiency, lower investment costs and lower emission rates. Although these characteristics may not drastically change over time, either immediate or irreversible investment decisions might be reconsidered under the current selling prices of heat, power and CO(2) allowances.

  2. DENSIFICATION OF WOOD VENEERS COMBINED WITH OIL-HEAT TREATMENT. PART III: CELL WALL MECHANICAL PROPERTIES DETERMINED BY NANOINDENTATION

    Directory of Open Access Journals (Sweden)

    Cecillia Bustos Avila,

    2012-02-01

    Full Text Available Compression under the effect of heat and steam, also called thermo-hygromechanical (THM densification, can increase wood density and therefore improve its strength, stiffness, and hardness. Oil-heat treatment (OHT is also known to reduce wood’s hygroscopicity and improve dimensional stability. A combination of both treatments can therefore produce wood with improved mechanical properties and dimensional stability. The objective of this project was to determine cell wall mechanical properties of THM-densified and OHT wood. Trembling aspen veneers were densified by a THM process and subsequently treated in canola oil at 200 and 220°C. Nanoindentations were performed in earlywood cell walls. The results show that cell wall longitudinal modulus of elasticity increased significantly from 13.5 GPa for the control to a maximum of 18.2 GPa for THM densified wood with or without OHT. Cell wall hardness increased from 0.27 GPa to a maximum of 0.43 GPa. Both THM densification and OHT significantly increased cell wall hardness. Therefore, the increase in mechanical properties of THM-densified and OHT wood can be due to an increase in wood density resulting from a reduction in porosity but also to an increase in the mechanical properties of the cell wall.

  3. Analysis and Assessments of Combined Cooling, Heating and Power Systems in Various Operation Modes for a Building in China, Dalian

    Directory of Open Access Journals (Sweden)

    Huanan Li

    2013-05-01

    Full Text Available Combined Cooling, Heating and Power (CCHP systems have been widely used in different kinds of buildings to make better use of fuels because of their high overall efficiency. This paper presents a mathematical analysis of a CCHP system in comparison to a Heating, Ventilation and Air Conditioning (HVAC system. The operation strategies following electric load (FEL, thermal load (FTL and a hybrid electric-thermal load (FHL are proposed and investigated in this study. Criteria, namely primary energy saving (PES, exergy efficiency (ηexergy, and CO2 emission reduction (CER are defined to evaluate the performances of CCHP systems for a hypothetical building located in Dalian (China. The results indicate that: (1 a new mathematical foundation is established to find whether the recovered thermal energy and the amount of electricity generated by the power generation unit (PGU are enough to provide the energy required; (2 the CCHP system does not always perform better than a HVAC system from an instantaneous perspective, especially in FTL mode; (3 the CCHP system in FEL operation mode can be seen as a suitable energy system in Dalian from the annual performance perspective. Furthermore, a sensitivity analysis is presented in order to show how the performances vary due to the changes of various technical variables.

  4. Effects Of The Combined Heat And Cryogenic Treatment On The Stability Of Austenite In A High Co-Ni Steel

    Directory of Open Access Journals (Sweden)

    Gruber M.

    2015-09-01

    Full Text Available The stability of austenite is one of the most dominant factors affecting the toughness properties of high Co-Ni steels such as Aermet 100 and AF1410. Thus, the aim of this work was to get a deeper understanding on the impact of combined heat and cryogenic treatment on the stability of retained and reverted austenite. In order to characterize the evolution of the phase fraction of austenite during tempering at different temperatures and times, X-ray diffraction analyses were carried out. The stability of austenite, which was formed during tempering, was analyzed with dilatometric investigations by studying the transformation behavior of the austenite during cooling from tempering temperature down to −100°C. Additionally, transmission electron microscopy investigations were performed to characterize the chemical composition and phase distribution of austenite and martensite before and after tempering.

  5. Combination of chemical analyses and animal feeding trials as reliable procedures to assess the safety of heat processed soybean seeds.

    Science.gov (United States)

    Vasconcelos, Ilka M; Brasil, Isabel Cristiane F; Oliveira, José Tadeu A; Campello, Cláudio C; Maia, Fernanda Maria M; Campello, Maria Verônica M; Farias, Davi F; Carvalho, Ana Fontenele U

    2009-06-10

    This study assessed whether chemical analyses are sufficient to guarantee the safety of heat processing of soybeans (SB) for human/animal consumption. The effects of extrusion and dry-toasting were analyzed upon seed composition and performance of broiler chicks. None of these induced appreciable changes in protein content and amino acid composition. Conversely, toasting reduced all antinutritional proteins by over 85%. Despite that, the animals fed on toasted SB demonstrated a low performance (feed efficiency 57.8 g/100 g). Extrusion gave place to higher contents of antinutrients, particularly of trypsin inhibitors (27.53 g/kg flour), but animal performance was significantly (p trials, extrusion appears to be the safest method. In conclusion, in order to evaluate the reliability of any processing method intended to improve nutritional value, the combination of chemical and animal studies is necessary.

  6. Coal water slurry in 0.25 MW furnace

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Cao, X.; Zhou, Z. (and others) [CUMT, Beijing (China). School of Chemical and Environmental Engineering

    2004-07-01

    Thermal state comparative test between the normal coal water slurry (CWS)and black liquor CWS from Xinwen was performed in 0.25 MW furnace for the purpose of investigating the industrial application feasibility of black liquor CWS. Performances of flow, atomization, kindling, burning, fouling, slagging, and pollutant emission were studied. The fouling and slagging tendency for two CWSs were analyzed using a self-made heat flux meter. The results show that the black liquor CWS is a fuel with good flowability and atomization, easy firing, stable burning, low pollutant emission, low ash fusion point, and strong slagging tendency, in contrast with the normal CWS. So it is feasible for the black liquor CWS to be used in industrial boilers. 7 refs., 8 figs.

  7. The DAN-AERO MW Experiments

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Bak, Christian; Schmidt Paulsen, Uwe

    This report describes the DAN-AERO MW experiments carried out within a collaborative, three years research project between Risø DTU and the industrial partners LM Glasfiber, Siemens Wind Power, Vestas Wind Systems A/S and the utility company DONG Energy. The main objective of the project was to e......This report describes the DAN-AERO MW experiments carried out within a collaborative, three years research project between Risø DTU and the industrial partners LM Glasfiber, Siemens Wind Power, Vestas Wind Systems A/S and the utility company DONG Energy. The main objective of the project...... in a wind tunnel and the unsteady 3D flow conditions on a rotor. The different transition characteristics might explain some of the differences between the 2D and 3D airfoil data and the experiments have been set up to provide data on this subject. The overall experimental approach has been to carry out...

  8. Parametric and exergetic analysis of a two-stage transcritical combined organic Rankine cycle used for multiple grades waste heat recovery of diesel engine

    Science.gov (United States)

    Tian, H.; Zhang, J.; Xu, X. F.; Shu, G. Q.; Wei, H. Q.

    2013-12-01

    Diesel engine has multiple grades of waste heat with different ratios of combustion heat, exhaust is 400 °C with the ratio of 21% and coolant is 90 °C with 19%. Few previous publications investigate the recovery of multiple grades waste heat together. In this paper, a two-stage transcritical combined organic rankine cycle (CORC) is presented and analyzed. In the combined system, the high and low temperature stages transcritical cycle recover the high grades waste heat, and medium to low grades waste heat respectively, and being combined efficiently. Meanwhile, the suitable working fluids for high stage are chosen and analyzed. The cycle parameters, including thermal efficiency (ηth), net power output (Pnet), energy efficiency (ηexg) and global thermal efficiency of DE-CORC(ηglo) have also been analyzed and optimized. The results indicate that this combined system could recover all the waste heat with a high recovery ratio (above 90%) and obtain a maximum power output of 37kW for a DE of 243kW. The global thermal efficiency of DE-CORC can get a max value of 46.2% compared with 40% for single DE. The results also indicate that all the energy conversion process have a high exergy efficiency.

  9. Realizalion of the 9200-MW Generation Assets

    Institute of Scientific and Technical Information of China (English)

    Peng Yuanchang; Yan Qingxu

    2007-01-01

    @@ With a process of disposition obeying market rules and a result of realization at a cost of 18.7 billion Yuan which is 56% excess, the State Electricity Regulatory Commission, the organizers for realization of the 9200-MW generation assets (the so-called "920 Project") didn't fail to accomplish its mission and withdrew the curtain of power reform in the 11th Five-Year period with a satisfactory performance.

  10. HEAT PUMP STATION WITH CARBON DIOXIDE AS A WORKING FLUID ENERGY EFFICIENCY GROWTH IN COMBINED DISTRICT HEATING SYSTEM DUE TO ITS CONTROL SYSTEM OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Sit B.M.

    2008-04-01

    Full Text Available A diagram of the heat pump station (HPS for the central heat supply station of the district heating system, which gets the power from the CHP plant is examined. A block diagram of the control of the system and compressor pressure control system are examined. The description of the control laws of evaporator at the variable heat load of the HPS and control laws of the gas cooler taking into account the goal of achieving the maximum of COP of HPS is shown as well.

  11. Exergy analysis and simulation of a 30MW cogeneration cycle

    Science.gov (United States)

    Dev, Nikhil; Samsher; Kachhwaha, S. S.; Attri, Rajesh

    2013-06-01

    Cogeneration cycle is an efficient mean to recover the waste heat from the flue gases coming out of gas turbine. With the help of computer simulation, design parameters may be selected for the best performance of cogeneration cycle. In the present work a program is executed in software EES on the basis of mathematical modelling described in paper to study cogeneration cycle performance for different parameters. Results obtained are compared with the results available in literature and are found in good agreement with them. Real gas and water properties are inbuilt in the software. Results show that enthalpy of air entering the combustion chamber is higher than that of the flue gases at combustion chamber outlet. For different operative conditions, energy and exergy efficiencies follow similar trends; although, exergy efficiency values are always lower than the corresponding energy efficiency ones. From the results it is found that turbine outlet temperature (TIT) of 524°C is uniquely suited to efficient cogeneration cycle because it enables the transfer of heat from exhaust gas to the steam cycle to take place over a minimal temperature difference. This temperature range results in the maximum thermodynamic availability while operating with highest temperature and highest efficiency cogeneration cycle. Effect of cycle pressure ratio (CR), inlet air temperature (IAT) and water pressure at heat recovery steam generator (HRSG) inlet on the 30MW cogeneration cycle is also studied.

  12. Combined resistive and laser heating technique for in situ radial X-ray diffraction in the diamond anvil cell at high pressure and temperature.

    Science.gov (United States)

    Miyagi, Lowell; Kanitpanyacharoen, Waruntorn; Raju, Selva Vennila; Kaercher, Pamela; Knight, Jason; MacDowell, Alastair; Wenk, Hans-Rudolf; Williams, Quentin; Alarcon, Eloisa Zepeda

    2013-02-01

    To extend the range of high-temperature, high-pressure studies within the diamond anvil cell, a Liermann-type diamond anvil cell with radial diffraction geometry (rDAC) was redesigned and developed for synchrotron X-ray diffraction experiments at beamline 12.2.2 of the Advanced Light Source. The rDAC, equipped with graphite heating arrays, allows simultaneous resistive and laser heating while the material is subjected to high pressure. The goals are both to extend the temperature range of external (resistive) heating and to produce environments with lower temperature gradients in a simultaneously resistive- and laser-heated rDAC. Three different geomaterials were used as pilot samples to calibrate and optimize conditions for combined resistive and laser heating. For example, in Run#1, FeO was loaded in a boron-mica gasket and compressed to 11 GPa then gradually resistively heated to 1007 K (1073 K at the diamond side). The laser heating was further applied to FeO to raise temperature to 2273 K. In Run#2, Fe-Ni alloy was compressed to 18 GPa and resistively heated to 1785 K (1973 K at the diamond side). The combined resistive and laser heating was successfully performed again on (Mg0.9Fe0.1)O in Run#3. In this instance, the sample was loaded in a boron-kapton gasket, compressed to 29 GPa, resistive-heated up to 1007 K (1073 K at the diamond side), and further simultaneously laser-heated to achieve a temperature in excess of 2273 K at the sample position. Diffraction patterns obtained from the experiments were deconvoluted using the Rietveld method and quantified for lattice preferred orientation of each material under extreme conditions and during phase transformation.

  13. Combined resistive and laser heating technique for in situ radial X-ray diffraction in the diamond anvil cell at high pressure and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Miyagi, Lowell [Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112 (United States); Department of Earth Sciences, Montana State University, Bozeman, Montana 59717 (United States); Kanitpanyacharoen, Waruntorn; Kaercher, Pamela; Wenk, Hans-Rudolf; Alarcon, Eloisa Zepeda [Department of Earth and Planetary Science, University of California, Berkeley, California 94720 (United States); Raju, Selva Vennila [Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States); HiPSEC, Department of Physics, University of Nevada, Las Vegas, Nevada 89154 (United States); Knight, Jason; MacDowell, Alastair [Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States); Williams, Quentin [Department of Earth and Planetary Science, University of California, Santa Cruz, California 95064 (United States)

    2013-02-15

    To extend the range of high-temperature, high-pressure studies within the diamond anvil cell, a Liermann-type diamond anvil cell with radial diffraction geometry (rDAC) was redesigned and developed for synchrotron X-ray diffraction experiments at beamline 12.2.2 of the Advanced Light Source. The rDAC, equipped with graphite heating arrays, allows simultaneous resistive and laser heating while the material is subjected to high pressure. The goals are both to extend the temperature range of external (resistive) heating and to produce environments with lower temperature gradients in a simultaneously resistive- and laser-heated rDAC. Three different geomaterials were used as pilot samples to calibrate and optimize conditions for combined resistive and laser heating. For example, in Run1, FeO was loaded in a boron-mica gasket and compressed to 11 GPa then gradually resistively heated to 1007 K (1073 K at the diamond side). The laser heating was further applied to FeO to raise temperature to 2273 K. In Run2, Fe-Ni alloy was compressed to 18 GPa and resistively heated to 1785 K (1973 K at the diamond side). The combined resistive and laser heating was successfully performed again on (Mg{sub 0.9}Fe{sub 0.1})O in Run3. In this instance, the sample was loaded in a boron-kapton gasket, compressed to 29 GPa, resistive-heated up to 1007 K (1073 K at the diamond side), and further simultaneously laser-heated to achieve a temperature in excess of 2273 K at the sample position. Diffraction patterns obtained from the experiments were deconvoluted using the Rietveld method and quantified for lattice preferred orientation of each material under extreme conditions and during phase transformation.

  14. Combined effect of heat stress, dehydration and exercise on neuromuscular function in humans.

    Science.gov (United States)

    Ftaiti, F; Grélot, L; Coudreuse, J M; Nicol, C

    2001-01-01

    This study examined the combined effect of exercise induced hyperthermia and dehydration on neuromuscular function in human subjects. Six trained male runners ran for 40 min on a treadmill at 65% of their maximal aerobic velocity while wearing a tracksuit covered with an impermeable jacket and pants to impair the evaporation of sweat. These stressful experimental running conditions led the runners to a physiological status close to exhaustion. On average, the 40 min run ended at a heart rate of 196 (SD 8) beats.min-1, a tympanic temperature of 40 (SD 0.3) degrees C and with a loss of body mass of 2 (SD 0.5)%. Pre- and post-running strength tests included measurements of maximal knee extension and flexion torques in both isometric and isokinetic (at 60 and 240 degrees.s-1) conditions. A 20 s endurance test at 240 degrees.s-1 was also performed. Surface electromyographic (EMG) activity was recorded from six knee extensor and flexor muscles during the entire protocol. The treadmill run led to clear decrements in maximal extension torque and EMG activity both in isometric and at the slowest isokinetic velocity (60 degrees.s-1). However, no differences in these parameters were observed at 240 degrees.s-1. Furthermore, the EMG patterns of the major knee extensor and flexor muscles remained remarkably stable during the treadmill run. These results demonstrate that the exercise-induced hyperthermia and dehydration in the present experiments had only minor effects on the neuromuscular performance. However, it is also suggested that high internal body temperature per se could limit the production of high force levels.

  15. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Sudhagar [University of Georgia; Sokhansanj, Shahabaddine [ORNL; Togore, Sam [U.S. Department of Energy; Turhollow Jr, Anthony F [ORNL

    2010-03-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam3). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  16. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, S. [Biological and Agricultural Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602 (United States); Sokhansanj, S.; Turhollow, A.F. [Environmental Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831 (United States); Tagore, S. [Office of Biomass Program, U.S. Department of Energy, Washington, DC 20585 (United States)

    2010-03-15

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam{sup 3}). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery. (author)

  17. Predictive model for the reduction of heat resistance of Listeria monocytogenes in ground beef by the combined effect of sodium chloride and apple polyphenols.

    Science.gov (United States)

    Juneja, Vijay K; Altuntaş, Evrim Güneş; Ayhan, Kamuran; Hwang, Cheng-An; Sheen, Shiowshuh; Friedman, Mendel

    2013-06-03

    We investigated the combined effect of three internal temperatures (57.5, 60, and 62.5°C) and different concentrations (0 to 3.0 wt/wt.%) of sodium chloride (NaCl) and apple polyphenols (APP), individually and in combination, on the heat-resistance of a five-strain cocktail of Listeria monocytogenes in ground beef. A complete factorial design (3×4×4) was used to assess the effects and interactions of heating temperature, NaCl, and APP. All 48 combinations were tested twice, to yield 96 survival curves. Mathematical models were then used to quantitate the combined effect of these parameters on heat resistance of the pathogen. The theoretical analysis shows that compared with heat alone, the addition of NaCl enhanced and that of APP reduced the heat resistance of L. monocytogenes measured as D-values. By contrast, the protective effect of NaCl against thermal inactivation of the pathogen was reduced when both additives were present in combination, as evidenced by reduction of up to ~68% in D-values at 57.5°C; 65% at 60°C; and 25% at 62.5°C. The observed high antimicrobial activity of the combination of APP and low salt levels (e.g., 2.5% APP and 0.5% salt) suggests that commercial and home processors of meat could reduce the salt concentration by adding APP to the ground meat. The influence of the combined effect allows a reduction of the temperature of heat treatments as well as the salt content of the meat. Meat processors can use the predictive model to design processing times and temperatures that can protect against adverse effects of contaminated meat products. Additional benefits include reduced energy use in cooking, and the addition of antioxidative apple polyphenols may provide beneficial health affects to consumers.

  18. Modelling and multi-scenario analysis for electric heat tracing system combined with low temperature district heating for domestic hot water supply

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . In this study, electric heat tracing system was investigated as a solution to this dilemma. A model of electric heat tracing system for multi-storey buildings was built. Various pipe materials and insulation thicknesses as the parameters of the model were compared to make a comprehensive study. The performance......Low temperature district heating (LTDH) is a cost-efficient way of supplying space heating and domestic hot water (DHW) for buildings in urban areas. However, there is concern that the potential hygiene problems (Legionella) might occur if LTDH is implemented, especially for large buildings...... of the electric heating tracing system with LTDH was simulated by taking the user pattern into account. A smart control method based on thermostatic and real-time control was developed, and compared with normal control method. The impact of user pattern was tested by applying standard, stochastic, and real load...

  19. Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis

    OpenAIRE

    Gowtham Mohan; Sujata Dahal; Uday Kumar; Andrew Martin; Hamid Kayal

    2014-01-01

    Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases) liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a) electricity by combining steam rankine cycle using heat recovery steam generator (HRSG); (b) clean water by air gap membrane distillation (AGMD) plant; and (c) cooling by single stage vapor absorption chiller (VAC). The flue gases liber...

  20. Surface thermocouples for measurement of pulsed heat flux in the divertor of the Alcator C-Mod tokamak.

    Science.gov (United States)

    Brunner, D; LaBombard, B

    2012-03-01

    A novel set of thermocouple sensors has been developed to measure heat fluxes arriving at divertor surfaces in the Alcator C-Mod tokamak, a magnetic confinement fusion experiment. These sensors operate in direct contact with the divertor plasma, which deposits heat fluxes in excess of ~10 MW/m(2) over an ~1 s pulse. Thermoelectric EMF signals are produced across a non-standard bimetallic junction: a 50 μm thick 74% tungsten-26% rhenium ribbon embedded in a 6.35 mm diameter molybdenum cylinder. The unique coaxial geometry of the sensor combined with its single-point electrical ground contact minimizes interference from the plasma/magnetic environment. Incident heat fluxes are inferred from surface temperature evolution via a 1D thermal heat transport model. For an incident heat flux of 10 MW/m(2), surface temperatures rise ~1000 °C/s, corresponding to a heat flux flowing along the local magnetic field of ~200 MW/m(2). Separate calorimeter sensors are used to independently confirm the derived heat fluxes by comparing total energies deposited during a plasma pulse. Langmuir probes in close proximity to the surface thermocouples are used to test plasma-sheath heat transmission theory and to identify potential sources of discrepancies among physical models.

  1. Boiler model of a 300 Mw fossil fuel power plant for the turbine turning simulator; Modelo de caldera de una planta termoelectrica de 300 Mw para el simulador de rodado de turbina

    Energy Technology Data Exchange (ETDEWEB)

    Rossano Roman, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1993-07-01

    The objective of the model is to reproduce the behavior of a boiler of a 300 Mw fossil fuel unit, in the training turbine turning simulator. This simulator was designed to be used in the training that is performed in the control rooms or training centers of the fossil fuel power plants of the Comision Federal de Electricidad (CFE). In this article the equations of the model for a 300 Mw thermal plant are described, based in balances and physical relationships. The basic considerations and simplifications are shown. The model considers the combustion in the furnace, the dome, the downcomers, the recirculation pumps, the water walls, the superheater and the reheater. The mass and energy balances take into account the sensible heat of all the constituents involved, as well as the combustion heat. Heat transference zones by convection or by a combined mechanism convective-radiant, in the boiler furnace, are considered. The dome pressure is modeled with basis in the mass and energy balance, considering all the existing sources and sinks. The simulation also reflects the pressure transients due to thermal variations, combustion variations, and steam demand variations. The heat transference by convection is considered for all the tube banks along the combustion gases path to the stack. Comparisons were made with the design and operation data of the power station, using a selection of transient states to demonstrate de model fidelity. This selection was focussed of transients states, at the unit start up, since in this operation stage the turning and the heating of the turbine is accomplished. [Espanol] El objetivo del modelo es reproducir el comportamiento de una caldera de una unidad termoelectrica de 300 Mw, en el simulador para entrenamiento en rodado de turbina. Este simulador se diseno para ser utilizado en el entrenamiento que se realiza en los cuartos de control o centros de entrenamiento de las plantas termoelectricas de la Comision Federal de Electricidad (CFE

  2. Integration of bio-fired gas turbines in combined heat and power generation; Integrering av biogaseldad gasturbin i kraftvaermeanlaeggning

    Energy Technology Data Exchange (ETDEWEB)

    Genrup, Magnus; Jonshagen, Klas

    2011-01-15

    The aim of the project was to perform a pre-study of the potential to introduce a biofired gas turbine into the pre-heater train of a district heating plant. The incentive for the work is the desire (and political drivers) to increase bio-fuel usage in heat and power production. Sweden has also ratified the EU treaty of having 20 percent renewable in the system before 2020. There are several options at the hand but locally produced biofuels from either gasification or biological processes can be fired in a gas turbine. The size of the gas turbine is limited by shear size of the fuel plant and raw-material transport issues. Today, the maximum electrical efficiency for large-scale advanced plants is on the order of 60 percent. This level is, however, not feasible for smaller size units and one can expect much lower levels. Another possibility is to re-power an existing plant and use the exhaust heat from the gas turbine. Either to produce steam in a heat recovery steam generator, heat boiler combustion air (and variants) or to reduce pre-heater extraction through by-passing the pre-heaters. Previous studies have shown that one could expect very high efficiency levels if the heat could be utilized in the feed water to the boiler. This is typically coupled to the admission pressure level and super-critical plant may have feed water temperature exceeding 300 deg C. The aim of this project was to investigate the potential from introducing this technology into a certain typical Swedish/Nordic turbine based district heating plant. A typical plant has modest admission data (compared to an ultra super-critical plant), hence lower final feed water temperature. A lower final temperature makes it more troublesome to effectively use the exhaust heat from the gas turbine. A further improvement is possible by introducing reheat. There are several practical limitations, where the most severe is the need to extract the full turbine flow and induce it after the reheater. The only

  3. A Hybrid Power Generation System Combined Parabolic Trough Solar Collectors and Chemical Heat Pump%槽式太阳能集热与化学热泵耦合的复合发电系统

    Institute of Scientific and Technical Information of China (English)

    王艳娟; 刘启斌; 金红光

    2014-01-01

    A hybrid power generation system combined parabolic trough solar collectors and chemical heat pump is proposed in the paper.The thermodynamic performance of the proposed system and the effects of the key operating parameters on the performances of the system were investigated.The relationship between the direct normal irradiation (DNI) and the performance of the proposed system was disclosed.When the DNI was larger than the design condition,variation of the mass flow rate of CaO for solar energy storage with the DNI was analyzed.In the design conditions,the output work of the system is 335.7 MW the thermal efficiency of the proposed system is 30.4%,and the solar-to-electric efficiency of the proposed system can reach 23.6%.The hybrid power system proposed can improve the thermal efficiency significantly by increasing the steam parameters compared to the conventional solar parabolic trough power generating system.%本文提出了一种抛物槽式太阳能集热与化学热泵耦合的复合发电系统,对其热力性能进行了分析,并研究了反应器中反应蒸汽温度、镜场加热给水温度等关键运行参数对系统性能的影响.研究了太阳能特征参数对系统性能的影响规律,分析了太阳直射辐照强度(DNI)高于设计工况时,储能材料氧化钙的量与DNI的关系.设计工况下,系统输出功335.7 MW,热效率为30.4%,发电效率23.6%.所提出的系统,为解决槽式太阳能单独热发电系统蒸汽参数低导致动力循环热效率低的难题提供了新途径.

  4. ABA is required for the accumulation of APX1 and MBF1c during a combination of water deficit and heat stress

    Science.gov (United States)

    Zandalinas, Sara I.; Balfagón, Damián; Arbona, Vicent; Gómez-Cadenas, Aurelio; Inupakutika, Madhuri A.; Mittler, Ron

    2016-01-01

    Abscisic acid (ABA) plays a key role in plant acclimation to abiotic stress. Although recent studies suggested that ABA could also be important for plant acclimation to a combination of abiotic stresses, its role in this response is currently unknown. Here we studied the response of mutants impaired in ABA signalling (abi1-1) and biosynthesis (aba1-1) to a combination of water deficit and heat stress. Both mutants displayed reduced growth, biomass, and survival when subjected to stress combination. Focusing on abi1-1, we found that although its stomata had an impaired response to water deficit, remaining significantly more open than wild type, its stomatal aperture was surprisingly reduced when subjected to the stress combination. Stomatal closure during stress combination in abi1-1 was accompanied by higher levels of H2O2 in leaves, suggesting that H2O2 might play a role in this response. In contrast to the almost wild-type stomatal closure phenotype of abi1-1 during stress combination, the accumulation of ascorbate peroxidase 1 and multiprotein bridging factor 1c proteins, required for acclimation to a combination of water deficit and heat stress, was significantly reduced in abi1-1. Our findings reveal a key function for ABA in regulating the accumulation of essential proteins during a combination of water deficit and heat stress. PMID:27497287

  5. Combining Aluminum Heat Treat with Hot Isostatic Pressing:A Comparison of Structure, Properties, and Processing Routes for a Cast Al-Si-Mg Alloy

    Institute of Scientific and Technical Information of China (English)

    Stephen J. Mashl

    2004-01-01

    Bodycote researchers have successfully demonstrated that a T6 heat treatment can be integrated with Densal(R), a proprietary, aluminum specific, hot isostatic pressing (HIP) process. In this combined operation, at least a portion of the solution heat treatment is conducted at elevated pressure. During development, two issues, adiabatic cooling during depressurization and a possible variation in the kinetics of homogenization resulting from conducting the solution heat treat at elevated pressure were perceived as factors which could alter the heat treat response fiom that seen in conventional processing.This paper reviews the results of experiments performed to A1-Si-Mg (A356.0) castings subjected to both combined and conventional processing routes. Results indicate that the combined HIP and heat treat process is an efficient means of achieving a microstructure characteristic of a conventionally T6 processed material while eliminating porosity within the casting. Further, the fatigue life of an A356.0 casting processed using the combined cycle can be improved by more than an order of magnitude over the as-cast and T6 treated component.

  6. Small-scale combined heat and power systems: Operating experience, economic efficiency, emissions; Kleinst-Blockheizkraftwerke: Betriebserfahrungen, Wirtschaftlichkeit, Emissionen

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbauer, G. [Forschungsstelle fuer Energiewirtschaft, Muenchen (Germany); Kraft-Woelfel, G. [Hamburgische Electricitaets-Werke AG, Hamburg (Germany)

    1998-06-01

    HEW is operating since 1995 within the framework of a HEW field experiment nine combined heat and power systems (CHP systems) manufactured by the Sener-Tec company which are installed in eight buildings in the city of Hamburg in addition to the customer-owned heating systems in these buildings. The objectives pursued with this project are to establish reliable performance data of the systems, so that the trial operation is accompanied by an extensive in-service measuring programme scanning performance data and emissions of the cogeneration systems driven by an Otto engine and a gas engine, having a rated output of 5.5 kW{sub el}. The systems meanwhile have been operating for 18 400 up to 21 400 hours. The article presents the major operating results documented in this field experiment as well as data for economic efficiency assessment and an analysis comparing the emissions of the CHP systems with those of other, equivalent systems for energy supply in buildings. (orig./CB) [Deutsch] HEW betreibe seit Anfang 1995 neun Heizkraftanlagen (HKA) der Firma SenerTec in acht Gebaeuden in Hamburg parallel zu den vorhandenen kundeneigenen Heizungsanlagen. Um ueber Betriebsverhalten und Emissionen dieser Gas-Ottomotor-Blockheizkraftwerke (BHKW) mit einer Nennleistung von 5,5 kW{sub el} Aufschluss zu gewinnen, wurde der Probebetrieb durch ein umfangreiches Messprogramm begleitet. Die Anlagen haben mittlerweile zwischen 18 400 und 21 400 Betriebsstunden erreicht. Die wesentlichen Betriebserfahrungen aus diesem Feldversuch, Ueberlegungen zur Wirtschaftlichkeit und ein Vergleich der Emissionen mit anderen Versorgungsvarianten werden im vorliegenden Beitrag kurz vorgestellt. (orig./RHM)

  7. The solution of the two-dimensional inverse heat transfer problem with the use of the FEM in combination with Trefftz functions

    Directory of Open Access Journals (Sweden)

    Maciejewska Beata

    2012-04-01

    Full Text Available The aim of this paper is to determine the boiling heat transfer coefficient for the cooling liquid flow in a rectangular minichannel with asymmetric heating. The main part of the test section is made up of a vertical minichannel of 1.0 mm depth. The heating foil on the side of the fluid flowing in the minichannel is singlesided enhanced on the selected area. The experiment is carried out with FC-72. The investigations focus on the transition from single-phase forced convection to nucleate boiling, that is, from the zone of boiling incipience further to developed boiling. Owing to the liquid crystal layer located on the heating surface contacting the glass, it is possible to measure the heating wall temperature distribution while increasing the heat flux transferred to the liquid flowing in the minichannel. The objective of the calculations is to evaluate a heat transfer model and numerical approach to solving the inverse boundary problem, and to calculate the heat transfer coefficient. This problem has been solved by means the finite element method in combination with Trefftz functions (FEMT. Trefftz functions are used to construct base functions in Hermite space of the finite element.

  8. Final design of a 24 MW radially-cooled insert for a 45 T hybrid system

    Energy Technology Data Exchange (ETDEWEB)

    Weggel, R.J.; Stejskal, V.; Bobrov, E.; Holowinski, M.; Williams, J.E.C. [M.I.T., Cambridge, MA (United States). Francis Bitter National Magnet Lab.

    1996-07-01

    For the National High Magnetic Field Laboratory the Francis Bitter National Magnet Laboratory has designed and is fabricating a 24 MW radially-cooled insert magnet. It is to add 31 teslas or more to the 14 T of the 616 mm bore superconducting magnet of Hybrid V, a system to generate at least 45 T in a 32 mm bore. The insert embodies many innovations for the sake of housing component commonality, unobstructed access for users, quick installation, efficiency, longevity and burnout isolation, while coping with power densities up to 7 W/mm{sup 3}, heat flux densities to 9 W/mm{sup 2}, water pressures to 40 bars, and fault loads to 3.5 MN. The upper surface of the housing is free of all electrical and hydraulic clutter. The compact coil package plugs in from above. Its three coils are electrically and hydraulically in series-parallel, with inward flow through the outer two coils. High water pressure and short passages give water velocities up to 40 m/s, despite depths of only 0.10 to 0.15 mm, thus achieving outstanding cooling efficiency and a peak temperature of only 68C. Conductors, with strengths to match local stresses, are two thicknesses of copper, three of Be-Cu and two of 24% Ag-Cu. All have excellent combinations of strength and electrical conductivity.

  9. The 2 MW Santa Clara Project

    Science.gov (United States)

    Eichenberger, Paul H.

    The City of Santa Clara, CA, USA, has hosted the world's first field demonstration of a molten carbonate fuel cell power plant. This US$46 million, 2 MW generator was a joint effort of five US utilities, the federal government, and two US research organizations. The demonstration used sixteen 125 kW stacks placed in four modules. The balance of plant (BOP) is the equipment that prepares and supplies the fuel to the stacks and converts the d.c. current to a.c. BOP construction started in April 1994, and was completed in June 1995. The BOP configuration allowed testing and development before installation of the four modules. The final full-temperature test was completed in February 1996. The four fuel cell modules were installed and cured, and power delivery began in April 1996. The plant operated for approximately 720 h at design output before electrical anomalies occurred and the plant was shut down for repairs. The plant restarted in August, but it soon became obvious that other problems had been caused by the electrical anomalies. The plant shut down and was reconfigured to a 1 MW plant. The restarted plant was ramped to 1 MW, but additional problems began to occur and the plant demonstration ended. The plant produced 2500 MWh, and operated at 1000°F, or higher, for over 5290 h. The plant set operational records, and demonstrated multistack, automatic control, and stable-field operation. Power quality met all standards with no measurable NOx or SOx output. The plant isolated itself from the grid during two major California, USA grid outages. The plant also experienced a shutdown of the automatic control system, and placed itself on hot standby using the mechanical field systems. The plant then restarted without incident.

  10. MW-Class Electric Propulsion System Designs

    Science.gov (United States)

    LaPointe, Michael R.; Oleson, Steven; Pencil, Eric; Mercer, Carolyn; Distefano, Salvador

    2011-01-01

    Electric propulsion systems are well developed and have been in commercial use for several years. Ion and Hall thrusters have propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system, while higher power systems are being considered to support even more demanding future space science and exploration missions. Such missions may include orbit raising and station-keeping for large platforms, robotic and human missions to near earth asteroids, cargo transport for sustained lunar or Mars exploration, and at very high-power, fast piloted missions to Mars and the outer planets. The Advanced In-Space Propulsion Project, High Efficiency Space Power Systems Project, and High Power Electric Propulsion Demonstration Project were established within the NASA Exploration Technology Development and Demonstration Program to develop and advance the fundamental technologies required for these long-range, future exploration missions. Under the auspices of the High Efficiency Space Power Systems Project, and supported by the Advanced In-Space Propulsion and High Power Electric Propulsion Projects, the COMPASS design team at the NASA Glenn Research Center performed multiple parametric design analyses to determine solar and nuclear electric power technology requirements for representative 300-kW class and pulsed and steady-state MW-class electric propulsion systems. This paper describes the results of the MW-class electric power and propulsion design analysis. Starting with the representative MW-class vehicle configurations, and using design reference missions bounded by launch dates, several power system technology improvements were introduced into the parametric COMPASS simulations to determine the potential system level benefits such technologies might provide. Those technologies providing quantitative system level benefits were then assessed for technical feasibility, cost, and time to develop. Key assumptions and primary

  11. Aeroelastic Optimization of MW Wind Turbines

    DEFF Research Database (Denmark)

    Hansen, Morten Hartvig; Zahle, Frederik

    This report contains the results from the Energy Development and Demonstration Project “Aeroelastic Optimization of MW wind turbine” (AeroOpt). The project has had the following five Work Packages: 1. Geometric non-linear, anisotropic beamelement forHAWC2 2. Closed-loop eigenvalue analysis...... of controlled wind turbines 3. Resonant wave excitation of lateral tower bending modes 4. Development of next generation aerodynamic design tools 5. Advanced design and verification of airfoils The purposes of these Work Packages are briefly described in the Preface and a summary of the results are given...

  12. Thermal Performance of Thin Type Radiant Floor Heating Combined with Fan-coil Heating%轻薄水地暖与分机盘管联合供暖热工性能研究

    Institute of Scientific and Technical Information of China (English)

    陈英杰; 李维; 陈立楠; 罗汉

    2014-01-01

    An experimental room was setted up for the heating system as research object, the heat source is air-source heat pump, the extreme is thin type radiant floor heating system combined with fan-coil heating system. The floor heating temperature and thermal performance under stable conditions are researched. The electricity consumption of fan-coil heating, radiant floor heating and radiant floor heating with fan-coil were analyzed through the data recorded by the meter. The value of the COP under three ways were compared after the calculation. Results indicate the indoor temperature response speed of the combined heating system is fast. Within the scope of the indoor temperature requirements, the average floor surface temperature is appropriate with less electricity consumption, the combined heating system is more energy-saving and more comfortable.%以空气源热泵为热源、风机盘管与地板辐射为末端的供暖系统作为研究对象,搭建了实验房间,对轻薄水地暖与风机盘管在供暖系统中的升温和稳定工况下的热工性能进行了实验研究,通过电表记录的数据比较了单开风盘连续运行、单开地板供暖连续运行、同时地板与风机盘管联合供暖各自的耗电量,通过计算比较了3种方式下的COP值,得出地板辐射与风机盘管联合供暖的室内温度响应速度快,在室内温度要求范围内,地板表面平均温度适宜、耗电量少,地板辐射与风机盘管联合供暖方式更节能、更舒适。

  13. Simulation and optimization study on a solar space heating system combined with a low temperature ASHP for single family rural residential houses in Beijing

    DEFF Research Database (Denmark)

    Deng, Jie; Tian, Zhiyong; Fan, Jianhua

    2016-01-01

    with good building insulation were undertaken to figure out the system economical efficiency in the rural regions of Beijing. The results show that the payback periods of the solar space heating system combined with the ASHP with the collector areas 15.04-22.56 m2 are 17.3-22.4 years for the established......A pilot project of the solar water heating system combined with a low temperature air source heat pump (ASHP) unit was established in 2014 in a detached residential house in the rural region of Beijing, in order to investigate the system application prospect for single family houses via system...... optimization design and economic analysis. The established system was comprised of the glass heat-pipe based evacuated tube solar collectors with a gross area of 18.8 m2 and an ASHP with a stated heating power of 8 kW for the space heating of a single family rural house of 81.4 m2. The dynamic thermal...

  14. 20 MW Flywheel frequency regulation plant

    Energy Technology Data Exchange (ETDEWEB)

    Arseneaux, James [Beacon Power LLC, Wilmington, MA (United States)

    2015-02-05

    Hazle designed, built, commissioned, and operates a utility-scale 20 MW flywheel energy storage plant in Hazle Township, Pennsylvania (the Hazle Facility) using flywheel technology developed by its affiliate, Beacon Power, LLC (Beacon Power). The Hazle Facility provides frequency regulation services to the regional transmission organization, PJM Interconnection, LLC (PJM), through its participation in PJM’s Regulation Market (a market-based system for the purchase and sale of the Regulation ancillary service). The zero emission Hazle Facility is designed for a 20 year-life over which it is capable of performing at least 100,000 full depth of discharge cycles. To achieve its 20 MW capacity, the Hazle Facility is comprised of two hundred of Beacon Power’s 100 kilowatt (kW)/25 kilowatt/hour (kWh) flywheels connected in parallel. The Hazle Facility can fully respond to a signal from PJM in less than 2 seconds. The Hazle facility was constructed in an economic development zone designated by the Commonwealth of Pennsylvania and its construction relied on local contractors and labor for completion.

  15. A Co-Powered Biomass and Concentrated Solar Power Rankine Cycle Concept for Small Size Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    Eileen Tortora

    2013-03-01

    Full Text Available The present work investigates the matching of an advanced small scale Combined Heat and Power (CHP Rankine cycle plant with end-user thermal and electric load. The power plant consists of a concentrated solar power field co-powered by a biomass furnace to produce steam in a Rankine cycle, with a CHP configuration. A hotel was selected as the end user due to its high thermal to electric consumption ratio. The power plant design and its operation were modelled and investigated by adopting transient simulations with an hourly distribution. The study of the load matching of the proposed renewable power technology and the final user has been carried out by comparing two different load tracking scenarios, i.e., the thermal and the electric demands. As a result, the power output follows fairly well the given load curves, supplying, on a selected winter day, about 50 GJ/d of thermal energy and the 6 GJ/d of electric energy, with reduced energy dumps when matching the load.

  16. Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ulsh, M.; Wheeler, D.; Protopappas, P.

    2011-08-01

    The U.S. Department of Energy (DOE) is interested in supporting manufacturing research and development (R&D) for fuel cell systems in the 10-1,000 kilowatt (kW) power range relevant to stationary and distributed combined heat and power applications, with the intent to reduce manufacturing costs and increase production throughput. To assist in future decision-making, DOE requested that the National Renewable Energy Laboratory (NREL) provide a baseline understanding of the current levels of adoption of automation in manufacturing processes and flow, as well as of continuous processes. NREL identified and visited or interviewed key manufacturers, universities, and laboratories relevant to the study using a standard questionnaire. The questionnaire covered the current level of vertical integration, the importance of quality control developments for automation, the current level of automation and source of automation design, critical balance of plant issues, potential for continuous cell manufacturing, key manufacturing steps or processes that would benefit from DOE support for manufacturing R&D, the potential for cell or stack design changes to support automation, and the relationship between production volume and decisions on automation.

  17. Nonablative skin tightening with a variable depth heating 1310-nm wavelength laser in combination with surface cooling.

    Science.gov (United States)

    Alexiades-Armenakas, Macrene

    2007-11-01

    A near-infrared laser with the ability to target different depths within skin has been developed and evaluated for the application of facial and neck skin tightening in a pilot clinical study. The device consists of a combination of a 1310-nm wavelength and sapphire contact cooling. Cooling temperature and laser pulse duration were varied to target different dermal depths in various subgroups of the subject population. Quantitative changes in various categories characterizing the aging skin employing a comprehensive grading scale as well as subject satisfaction were calculated. A mean improvement of 7.9% (95% CI [confidence interval] 3.6-12.3) in laxity and 10.6% (95% CI 5.8-15.4) in rhytides was determined by quantitative grading at one month after the treatment regimen. These values were 11.0% (5.5-16.5) and 11.7% (5.8-17.7) at 3 months after the treatment regimen. The percent of patients reporting mild or better improvement in laxity of the face and neck was 78% and 61% at one month, and 63% and 61% at 3 months, respectively. The discomfort was minimal. Side effects were limited to short-term erythema and edema. In summary, a variable depth heating laser can achieve skin tightening and wrinkle reduction with high subject satisfaction.

  18. Performance analysis of a direct expansion air dehumidification system combined with membrane-based total heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Cai-Hang; Zhang, Li-Zhi; Pei, Li-Xia [Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China)

    2010-09-15

    A direct expansion (DX) air dehumidification system is an efficient way to supply fresh and dry air to a built environment. It plays a key role in preventing the spread of respiratory disease like Swine flu (H1N1). To improve the efficiency of a conventional DX system in hot and humid regions, a new system of DX in combination with a membrane-based total heat exchanger is proposed. Air is supplied with dew points. A detailed mathematical modeling is performed. A cell-by-cell simulation technique is used to simulate its performances. A real prototype is built in our laboratory in South China University of Technology to validate the model. The effects of inlet air humidity and temperature, evaporator and condenser sizes on the system performance are investigated. The results indicate that the model can predict the system accurately. Compared to a conventional DX system, the air dehumidification rate (ADR) of the novel system is 0.5 times higher, and the coefficient of performance (COP) is 1 times higher. Furthermore, the system performs well even under harsh hot and humid weather conditions. (author)

  19. Combined microwave irradiation and intraarticular glutamine administration-induced HSP70 expression therapy prevents cartilage degradation in a rat osteoarthritis model.

    Science.gov (United States)

    Fujita, Shinya; Arai, Yuji; Nakagawa, Shuji; Takahashi, Kenji A; Terauchi, Ryu; Inoue, Atsuo; Tonomura, Hitoshi; Hiraoka, Nobuyuki; Inoue, Hiroaki; Tsuchida, Shinji; Mazda, Osam; Kubo, Toshikazu

    2012-03-01

    The objective of the present study was to investigate the effects of heat stimulation and glutamine (Gln) on the expression of extracellular matrix genes and heat shock protein 70 (HSP70) in rat articular cartilage in vivo and to determine whether HSP70 expression achieved with a combination of microwave (MW) and Gln suppresses osteoarthritis (OA) progression in a rat OA model. Stimulation at 40 W was assumed to be appropriate in the present study, and the effects of heat treatment at this intensity were evaluated. Articular cartilage was collected at 8 h after heat stimulation and/or intraarticular Gln administration, and total RNA was extracted. The expression of HSP70, aggrecan, and type II collagen was quantified using real-time RT-PCR. Cartilage samples from the OA model were subjected to hematoxylin and eosin (HE) and safranin O staining. HSP70 and aggrecan expression was greatest in a group receiving both MW and Gln. In the rat OA model, the severity of OA was significantly milder in a group receiving MW and Gln than in the control group. HSP70, stimulated by the combination of MW heat and Gln, may be involved in the suppression of OA progression.

  20. Dynamic simulation model for ultra supercritical 1 000 MW unit boilers%Dynamic simulation model for ultra supercritical 1000 MW unit boilers

    Institute of Scientific and Technical Information of China (English)

    XU Hui; XU Ershu

    2013-01-01

    On the basis of heat transfer characteristics of working fluid at different pressures inside the water wall tube and structure of the ultra supercritical 1 000 MW unit once through boiler in Jianbi Power Plant,the varying phase transformation point method was adopted to establish the moving-boundary dynamic simulation model of water wall in ultra supercritical once through boilers,especially the length variation of hot water section,evaporation section and superheat section against the load changing.On this basis,the real-time dynamic simulation model for ultra-supercritical 1 000 MW unit boiler in Jianbi Power Plant was built on the STAR-90 simulation platform.The dynamic and static characteristics test showed that,this model can simulate the unit's startup/shutdown process and some typical fault conditions accurately,and had good dynamic and static performance.

  1. Combining Low-Energy Electrical Resistance Heating with Biotic and Abiotic Reactions for Treatment of Chlorinated Solvent DNAPL Source Area

    Science.gov (United States)

    2012-12-01

    treatment zones using pneumatic injection. In: Chlorinated Solvent and DNAPL Remediation: Innovative Strategies for Subsurface Cleanup; Henry, S.M...source areas”. In: S. M. Henry, and S. D. Warner (eds), Innovative strategies for the remediation of chlorinated solvents and DNAPLs in the subsurface...8217s ond -- -j,O - e ,, , tt’ J?5s I -- o-8 3’ W of- ISB-mw 2- -- f-- {).Jif"’f ,ruo~/wood_1 bric ~ f-- I f-z,o - 8 {2.1111 2 .. \\ r-- {Flu) ~,c/ r

  2. Technology used to operate the 300-MW power unit topped with a GTE-110 gas turbine

    Science.gov (United States)

    Berezinets, P. A.; Doverman, G. I.

    2010-09-01

    Results obtained from mathematical simulation of operations for starting the 300-MW power unit topped with a GTE-110 gas turbine installed at the GRES-24 district power station of OAO OGK-6 wholesale power-generating company are described. It is shown that operations on speeding up the steam turbine from a cold state to its idle running mode can be carried out solely by using the heat of exhaust gases from the gas turbine unit without supplying fuel to the boiler.

  3. Towards high concentration enhancement of microfluidic temperature gradient focusing of sample solutes using combined AC and DC field induced Joule heating.

    Science.gov (United States)

    Ge, Zhengwei; Wang, Wei; Yang, Chun

    2011-04-07

    It is challenging to continuously concentrate sample solutes in microfluidic channels. We present an improved electrokinetic technique for enhancing microfluidic temperature gradient focusing (TGF) of sample solutes using combined AC and DC field induced Joule heating effects. The introduction of an AC electric field component services dual functions: one is to produce Joule heat for generating temperature gradient; the other is to suppress electroosmotic flow. Consequently the required DC voltages for achieving sample concentration by Joule heating induced TGF are reduced, thereby leading to smaller electroosmotic flow (EOF) and thus backpressure effects. As a demonstration, the proposed technique can lead to concentration enhancement of sample solutes of more than 2500-fold, which is much higher than the existing literature reported microfluidic concentration enhancement by utilizing the Joule heating induced TGF technique.

  4. Analysis of Entropy Generation of Combined Heat and Mass Transfer in Internal and External Flows with the Assumption of Local Thermodynamic Equilibrium

    Institute of Scientific and Technical Information of China (English)

    ShouguangYao

    1994-01-01

    In this paper,the control volume method is used to establish the general expression of entropy generation due to combined convective heat and mass transfer in internal and external fluid streams.The expression accounts for irreversibilities due to the presence of heat transfer across a finite temperature difference,mass transfer across a finite difference in the chemical potential of a species,and due to flow friction.Based on the assumption of local thermodynamic equilibrium,the generalized form of the Gibbs equation is used in this analysis.The results are applied to two fundamental problems of forced convection heat and mass transfer in internal and external flows.After minimizing the entropy generation,useful conclusions are derived that are typical of the second law viewpoint for the definition of the optimum operation conditions for the specified applications.which is a valuable criterion for optimum design of heat and fluid flow devices.

  5. Combined refrigeration / heat pump installation at the St. Jakob Arena in Basle; Kombinierte Kaelte- / Waermepumpen- Verdichter-Anlage in der Eissporthalle St. Jakob ARENA, 4142 Muenchenstein, Basel

    Energy Technology Data Exchange (ETDEWEB)

    Frey, P. [P. Frey and Partner, Beratende Ingenieure und Planer, Wilen bei Wil (Switzerland); Bertozzi, L. [Ingenieurbuero Bertozzi, Ingenieurbuero fuer Haustechnik, Chur (Switzerland)

    2003-07-01

    This intermediate report for the Swiss Federal Office of Energy describes the combined refrigeration and heat-pump unit in use at the new 'St. Jakob Arena' ice-sport-centre near Basle, Switzerland, which includes an indoor ice-rink. The centre has been equipped with an ammonia-based refrigeration system with two reciprocating compressors, which can be run in parallel or as part of a 2-stage-process. The two modes of operation are described. In the 'parallel' operating mode, both compressors are used for cold production only. In the '2-stage' operating mode, one compressor acts as the lower stage for cold production an the second as the upper stage for heat production using the rejected heat from condenser of the first stage as a heat source. Data is presented on the system's performance during the first operational season of the installation.

  6. Thermo economic comparison of conventional micro combined heat and power systems with solid oxide fuel cell systems for small scale applications

    DEFF Research Database (Denmark)

    Batens, Ellen; Cuellar, Rafael; Marissal, Matthieu

    2013-01-01

    Fuel cells have the potential to reduce domestic energy consumption by providing both heat and electricity at the point of use. However, the cost of installing the fuel cell must be sufficiently competitive to be recovered by the savings made over its lifetime. The goal of this paper is to carry...... out a thermo economic comparison of a conventional micro combined heat and power systems with solid oxide fuel cell systems. A model to estimate the savings and cost targets for solid oxide fuel cell systems is presented. A comparison between fuel cell technologies in the danish market with “state...... of the art” traditional heat and power generation technologies currently used in Denmark is considered. The conventional method of covering electrical, heating (e.g. hot water) and cooling (e.g. space cooling) load demands is by purchasing electricity from the electricity network grid and with a fossil fuel...

  7. Optimised Control of 10 MW Photovoltaic (PV) Plant with 1MW / 1MWh Battery

    DEFF Research Database (Denmark)

    Nørgård, Per Bromand; Bindner, Henrik W.; Thavlov, Anders

    2016-01-01

    MWp PV capacity and 1MW/1MWh battery storage at the campus. This paper presents the specific context of the power system in Cyprus and the future UCY microgrid along with the possible and expected impacts of the PV plant and Battery Energy Storage System. The battery control strategies are tested...

  8. Aeroelastic Optimization of a 10 MW Wind Turbine Blade with Active Trailing Edge Flaps

    DEFF Research Database (Denmark)

    Barlas, Athanasios; Tibaldi, Carlo; Zahle, Frederik;

    2016-01-01

    This article presents the aeroelastic optimization of a 10MW wind turbine ‘smart blade’ equipped with active trailing edge flaps. The multi-disciplinary wind turbine analysis and optimization tool HawtOpt2 is utilized, which is based on the open-source framework Open-MDAO. The tool interfaces...... to several state-of-the art simulation codes, allowing for a wide variety of problem formulations and combinations of models. A simultaneous aerodynamic and structural optimization of a 10 MW wind turbine rotor is carried out with respect to material layups and outer shape. Active trailing edge flaps...

  9. Agent-Based Control of Distributed Electricity Generation with Micro Combined Heat and Power: Cross-Sectoral Learning for Process and Infrastructure Engineers

    NARCIS (Netherlands)

    Van Dam, K.H.; Houwing, M.; Lukszo, Z.; Bouwmans, I.

    2007-01-01

    For the distributed control of an electricity infrastructure incorporating clusters of residential combined heat and power units (micro-CHP or μCHP) a Multi-Agent System approach is considered. The network formed by households generating electricity with μCHP units and the facilitating energy

  10. ANALYSIS OF THE IMPACT PROPERTIES OF THE COOLANT RECOVERY SYSTEM HEAT LOSSES OF COMBINED COMPRESSOR-POWER PLANT ON ITS CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Yusha V.L.

    2012-12-01

    Full Text Available The paper presents results of theoretical analysis of the effectiveness of an ideal thermodynamic cycle internal combustion engine combined with an external utilization of exhaust heat. The influence of the properties of the coolant circuit of utilization on its operational parameters and characteristics of the power plant.

  11. Satellite combined heat and power plants and their legal autonomy; Satelliten-BHKW und deren rechtliche Eigenstaendigkeit

    Energy Technology Data Exchange (ETDEWEB)

    Loibl, Helmut [Kanzlei Paluka Sobola Loibl und Partner, Regensburg (Germany). Abt. Erneuerbare Energien

    2014-04-15

    Since the landmark decision by the German Court of Justice concerning the term ''plant'' in the context of biogas plants it should be clear beyond doubt that satellite combined heat and power plants (CHPs) are legally autonomous plants pursuant to Para. 3 No. 1 of the Renewable Energy Law (EEG). What has yet to be finally resolved are the conditions under which satellite CHPs are to be regarded as autonomous. This will be a question of distance on the one hand and of operation autonomy on the other. In the individual case both these factors will have to be assessed from the perspective of an average objective, informed citizen. To the extent that its heat and electricity are being utilised in a meaningful manner, the plant's autonomy will be beyond doubt, at least in operational terms. Regarding the remuneration to be paid for satellite CHPs the only case requiring special consideration is when a CHP falls under the EEG of 2012. In this case Para. 1 Section 1 Sentence 2 EEG provides that the remuneration for the CHP in question is to be calculated as if there was a single overall plant. To the extent that none of the CHPs fall under the EEG of 2012, the ruling remains that there is a separate entitlement to remuneration for each satellite CHP. This also holds in cases where satellite CHPs that were commissioned after 1 January 2012 are relocated. When a satellite CHP is replaced by a new one, the rate and duration of remuneration remain unchanged. However, when a new satellite CHP is added to an existing satellite CHP via a gas collector line it is to be treated according to the decisions of the Federal Court of Justice concerning biogas plant extensions: It falls under the law that applies to the existing CHP and has an entitlement to a new minimum remuneration period, albeit subject to the degression rate provided by the EEG version in question.

  12. Combined Heat and Power From Low Temperature Heat: HFO-1336mzz(Z) as a Working Fluid for Organic Rankine Cycles

    OpenAIRE

    Kontomaris, Konstantinos; Simoni, Luke D.; Nilsson, Mattias; Hamacher, Tim; Nes Rislå, Harald

    2016-01-01

    Increasing awareness of the environmental impacts associated with the extraction and combustion of fossil fuels and the continued uncertainty of fossil fuel supplies and prices are motivating a renewed interest in the utilization of abundantly available low temperature heat (e.g. waste heat from industrial or commercial processes, mobile or stationary internal combustion engines, geothermal heat, etc.). Conversion of heat to mechanic...

  13. Aeroelastic optimization of MW wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hartvig Hansen, M.; Zahle, F.

    2011-12-15

    This report contains the results from the Energy Development and Demonstration Project ''Aeroelastic Optimization of MW wind turbine'' (AeroOpt). The project has had the following five Work Packages: 1. Geometric non-linear, anisotropic beam element for HAWC2. 2. Closed-loop eigenvalue analysis of controlled wind turbines. 3. Resonant wave excitation of lateral tower bending modes. 4. Development of next generation aerodynamic design tools. 5. Advanced design and verification of airfoils. The purposes of these Work Packages are briefly described in the Preface and a summary of the results are given in Section 2. Thereafter, the results from each Work Package are described in eight subsequent chapters. (Author)

  14. Imbalance between oxygen photoreduction and antioxidant capacities in Symbiodinium cells exposed to combined heat and high light stress

    Science.gov (United States)

    Roberty, S.; Fransolet, D.; Cardol, P.; Plumier, J.-C.; Franck, F.

    2015-12-01

    During the last decades, coral reefs have been affected by several large-scale bleaching events, and such phenomena are expected to increase in frequency and severity in the future, thus compromising their survival. High sea surface temperature accompanied by high levels of solar irradiance has been found to be responsible for the induction of oxidative stress ultimately ending with the disruption of the symbiosis between cnidarians and Symbiodinium. For two decades, many studies have pointed to the water-water cycle (WWC) as being one of the primary mediators of this phenomenon, but the impacts of environmental stress on the O2 reduction by PSI and the associated reactive oxygen species (ROS)-detoxifying enzymes remain to be determined. In this study, we analyzed the impacts of acute thermal and light stress on the WWC in the model Symbiodinium strain A1. We observed that the high light treatment at 26 °C resulted in the up-regulation of superoxide dismutase, ascorbate peroxidase, and glutathione reductase activities and an increased production of ROS with no significant change in O2-dependent electron transport. Under high light and at 33 °C, O2-dependent electron transport was significantly increased relative to total electron transport. This increase was concomitant with a twofold increase in ROS generation compared with the treatment at 26 °C, while enzymes involved in the WWC were largely inactivated. These data show for the first time that combined heat and light stress inactivate antioxidant capacities of the WWC and suggests that its photoprotective functions are overwhelmed under these conditions. This study also indicates that cnidarians may be more prone to bleach if they harbor Symbiodinium cells having a highly active Mehler-type electron transport, unless they are able to quickly up-regulate their antioxidant capacities.

  15. Thermoeconomic Modeling and Parametric Study of a Photovoltaic-Assisted 1 MWe Combined Cooling, Heating, and Power System

    Directory of Open Access Journals (Sweden)

    Alexandros Arsalis

    2016-08-01

    Full Text Available In this study a small-scale, completely autonomous combined cooling, heating, and power (CCHP system is coupled to a photovoltaic (PV subsystem, to investigate the possibility of reducing fuel consumption. The CCHP system generates electrical energy with the use of a simple gas turbine cycle, with a rated nominal power output of 1 MWe. The nominal power output of the PV subsystem is examined in a parametric study, ranging from 0 to 600 kWe, to investigate which configuration results in a minimum lifecycle cost (LCC for a system lifetime of 20 years of service. The load profile considered is applied for a complex of households in Nicosia, Cyprus. The solar data for the PV subsystem are taken on an hourly basis for a whole year. The results suggest that apart from economic benefits, the proposed system also results in high efficiency and reduced CO2 emissions. The parametric study shows that the optimum PV capacity is 300 kWe. The minimum lifecycle cost for the PV-assisted CCHP system is found to be 3.509 million €, as compared to 3.577 million € for a system without a PV subsystem. The total cost for the PV subsystem is 547,445 €, while the total cost for operating the system (fuel is 731,814 € (compared to 952,201 € for a CCHP system without PVs. Overall the proposed system generates a total energy output of 210,520 kWh (during its whole lifetime, which translates to a unit cost of 17 €/kWh.

  16. Therapeutic efficacy of tumor-derived heat shock protein 70 immunotherapy combining interleukin-2 on tumor-bearing mice

    Institute of Scientific and Technical Information of China (English)

    傅庆国; 孟凡东; 沈晓东; 郭仁宣

    2003-01-01

    Objective To investigate the therapeutic efficacy of compound immunotherapy of tumor-derived heat shock protein 70 (HSP70) and interleukin-2 (IL-2) on tumor-bearing mice, and to provide reference for translating this strategy to human cancer. Methods Cell culture, techniques for protein extraction and purification, SDS-PAGE, Wes tern blot and capillary electrophoresis for HSP70 detection and purity analysis, and animal experiments were used. Mice were treated with HSP70 5 or 10 μg and IL-2 50 kU, 100 kU or 2 kU (maintaining dosage) at pre viously designated intervals. Results Both the mono-administration of either HSP70 or IL-2 and the compound immunoth erapy of HSP70 and IL-2 obviously inhibited the growth of the implanted tumor and prolonged the life span of the mice to different extents. However, long periods of tumor-free suvival (over 90 days) were demonstrated only in HSP70 10 μg group, HSP70 10 μg-IL-2 50 kU group, and HSP70 10 μg-IL-2 100 kU group (4 0%, 40%, 60% respectively). On the other hand, none of the mice in the rest gr oups achieved long-term survival. Statistical significance was apparent in com parison with the groups without long period survival (P<0.025-0.05). Conclusion Our research revealed that tumor-derived HSP70 immunotherapy was much more effective than IL-2 alone. And in compound immunotherapy, HSP70 was the main factor in delaying or eradicating the tumors. The proper combination of HSP70 and IL-2 (10 μg HSP70 and 100 kU IL-2 in this experimental mouse model) clea rly enhanced the immunotherapy efficacy which indicated that the specific immuno therapy as a main part of tumor immunotherapy assisted by cytokine immunotherapy would be a promising strategy in cancer treatment.

  17. Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis

    Directory of Open Access Journals (Sweden)

    Gowtham Mohan

    2014-10-01

    Full Text Available Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a electricity by combining steam rankine cycle using heat recovery steam generator (HRSG; (b clean water by air gap membrane distillation (AGMD plant; and (c cooling by single stage vapor absorption chiller (VAC. The flue gases liberated from the gas turbine power cycle is the prime source of energy for the tri-generation system. The heat recovered from condenser of steam cycle and excess heat available at the flue gases are utilized to drive cooling and desalination cycles which are optimized based on the cooling energy demands of the villas. Economic and environmental benefits of the tri-generation system in terms of cost savings and reduction in carbon emissions were analyzed. Energy efficiency of about 82%–85% is achieved by the tri-generation system compared to 50%–52% for combined cycles. Normalized carbon dioxide emission per MW·h is reduced by 51.5% by implementation of waste heat recovery tri-generation system. The tri-generation system has a payback period of 1.38 years with cumulative net present value of $66 million over the project life time.

  18. Propellant Vaporization as a Criterion for Rocket-Engine Design; Experimental Performance, Vaporization and Heat-Transfer Rates with Various Propellant Combinations

    Science.gov (United States)

    Clark, Bruce J.; Hersch, Martin; Priem, Richard J.

    1959-01-01

    Experimental combustion efficiencies of eleven propellant combinations were determined as a function of chamber length. Efficiencies were measured in terms of characteristic exhaust velocities at three chamber lengths and in terms of gas velocities. The data were obtained in a nominal 200-pound-thrust rocket engine. Injector and engine configurations were kept essentially the same to allow comparison of the performance. The data, except for those on hydrazine and ammonia-fluorine, agreed with predicted results based on the assumption that vaporization of the propellants determines the rate of combustion. Decomposition in the liquid phase may be.responsible for the anomalous behavior of hydrazine. Over-all heat-transfer rates were also measured for each combination. These rates were close to the values predicted by standard heat-transfer calculations except for the combinations using ammonia.

  19. Power and Efficiency Analysis of a Solar Central Receiver Combined Cycle Plant with a Small Particle Heat Exchanger Receiver

    Science.gov (United States)

    Virgen, Matthew Miguel

    Two significant goals in solar plant operation are lower cost and higher efficiencies. To achieve those goals, a combined cycle gas turbine (CCGT) system, which uses the hot gas turbine exhaust to produce superheated steam for a bottoming Rankine cycle by way of a heat recovery steam generator (HRSG), is investigated in this work. Building off of a previous gas turbine model created at the Combustion and Solar Energy Laboratory at SDSU, here are added the HRSG and steam turbine model, which had to handle significant change in the mass flow and temperature of air exiting the gas turbine due to varying solar input. A wide range of cases were run to explore options for maximizing both power and efficiency from the proposed CSP CCGT plant. Variable guide vanes (VGVs) were found in the earlier model to be an effective tool in providing operational flexibility to address the variable nature of solar input. Combined cycle efficiencies in the range of 50% were found to result from this plant configuration. However, a combustor inlet temperature (CIT) limit leads to two distinct Modes of operation, with a sharp drop in both plant efficiency and power occurring when the air flow through the receiver exceeded the CIT limit. This drawback can be partially addressed through strategic use of the VGVs. Since system response is fully established for the relevant range of solar input and variable guide vane angles, the System Advisor Model (SAM) from NREL can be used to find what the actual expected solar input would be over the course of the day, and plan accordingly. While the SAM software is not yet equipped to model a Brayton cycle cavity receiver, appropriate approximations were made in order to produce a suitable heliostat field to fit this system. Since the SPHER uses carbon nano-particles as the solar absorbers, questions of particle longevity and how the particles might affect the flame behavior in the combustor were addressed using the chemical kinetics software Chemkin

  20. Predictions of Alpha Heating in ITER L-mode and H-mode Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    R.V. Budny

    2011-01-06

    Predictions of alpha heating in L-mode and H-mode DT plasmas in ITER are generated using the PTRANSP code. The baseline toroidal field of 5.3 T, plasma current ramped to 15 MA and a flat electron density profile ramped to Greenwald fraction 0.85 are assumed. Various combinations of external heating by negative ion neutral beam injection, ion cyclotron resonance, and electron cyclotron resonance are assumed to start half-way up the density ramp. The time evolution of plasma temperatures and, for some cases, toroidal rotation are predicted assuming GLF23 and boundary parameters. Significant toroidal rotation and flow-shearing rates are predicted by GLF23 even in the L-mode phase with low boundary temperatures, and the alpha heating power is predicted to be significant if the power threshold for the transition to H-mode is higher than the planned total heating power. The alpha heating is predicted to be 8-76 MW in L-mode at full density. External heating mixes with higher beam injection power have higher alpha heating power. Alternatively if the toroidal rotation is predicted assuming that the ratio of the momentum to thermal ion energy conductivity is 0.5, the flow-shearing rate is predicted to have insignificant effects on the GLF23- predicted temperatures, and alpha heating is predicted to be 8-20 MW. In H-mode plasmas the alpha heating is predicted to depend sensitively on the assumed pedestal temperatures. Cases with fusion gain greater than 10 are predicted to have alpha heating greater than 80 MW.

  1. Hydrodynamics and Heat Transfer in the Case of Combined Flow in a Annular Channel of Small Cross Section

    Science.gov (United States)

    Komov, A. T.; Varava, A. N.; Dedov, A. V.; Zakharenkov, A. V.; Boltenko, É. A.

    2017-01-01

    The present work is a continuation of experimental investigations conducted at the Moscow Power Engineering Institute (MPEI) on heat-transfer intensification. Brief descriptions of the working section and structure of intensifiers are given and their basic geometric parameters are enumerated. New systematized experimental data on the coefficients of hydraulic resistance and heat transfer in the regime of single-phase convection are given in an extended range of regime parameters and geometric characteristics of the intensifiers. Considerable increase in the heat-transfer coefficient as a function of the geometric characteristics of the intensifier has been established experimentally. The values of the relative fin height, at which these are the maxima of heat transfer and hydraulic resistance, have been established. Calculated dependences for the coefficient of hydraulic resistance and heat transfer have been obtained.

  2. Feasibility Study for the Ivano-Frankivsk District Heating Repowering: Analysis of Options

    Energy Technology Data Exchange (ETDEWEB)

    Markel, L.; Popelka, A.; Laskarevsky, V.

    2002-03-20

    Part of the U.S. Initiative on Joint Implementation with the Ukraine Inter-Ministerial Commission on Climate Change, financed by the US Department of Energy. The project was implemented by a team consisting of the US company SenTech, Inc. and the Ukrainian company Esco-West. The main objective of the effort was to assess available alternatives of Ivano-Frankivsk (I-F) District Heating repowering and provide information for I-F's investment decision process. This study provides information on positive and negative technical and economic aspects of available options. Three options were analyzed for technical merit and economic performance: 1. Installation of cogeneration system based on Gas Turbine (GT) and Heat Recovery Heat Exchanger with thermal capacity of 30 MW and electrical capacity of 13.5 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. Equipment in this Option was sized for longest operating hours, about 8000 based on the available summer baseload. 2. Installation of Gas Turbine Combined Cycle (GTCC) and Heat Recovery Steam Generator (HRSG) with thermal capacity 45 MW and electrical capacity of 58.7 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. The equipment was sized for medium, shoulder season thermal load, and some cooling was assumed during the summer operation for extension of operating hours for electricity production. 3. Retrofit of six existing boilers (NGB) with total thermal capacity of 255.9 MW by installation of modern control system and minor upgrades. This option assumes only heat production with minimum investment. The best economic performance and the largest investment cost would result from alternative GTCC. This alternative has positive Net Present Value (NPV) with discount rate lower than about 12%, and has IRR slightly above 12%. The

  3. NCSX Plasma Heating Methods

    Energy Technology Data Exchange (ETDEWEB)

    H.W. Kugel; D. Spong; R. Majeski; M. Zarnstorff

    2003-02-28

    The NCSX (National Compact Stellarator Experiment) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral-beam injection, and radio-frequency. Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The plan is to provide 3 MW of 50 keV balanced neutral-beam tangential injection with pulse lengths of 500 msec for initial experiments, and to be upgradeable to pulse lengths of 1.5 sec. Subsequent upgrades will add 3 MW of neutral-beam injection. This Chapter discusses the NCSX neutral-beam injection requirements and design issues, and shows how these are provided by the candidate PBX-M (Princeton Beta Experiment-Modification) neutral-beam injection system. In addition, estimations are given for beam-heating efficiencies, scaling of heating efficiency with machine size an d magnetic field level, parameter studies of the optimum beam-injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of radio-frequency heating by mode-conversion ion-Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron-cyclotron heating. The initial MCIBW heating technique and the design of the radio-frequency system lend themselves to current drive, so that if current drive became desirable for any reason only minor modifications to the heating system described here would be needed. The radio-frequency system will also be capable of localized ion heating (bulk or tail), and possibly ion-Bernstein-wave-generated sheared flows.

  4. NCSX Plasma Heating Methods

    Energy Technology Data Exchange (ETDEWEB)

    Kugel, H. W.; Spong, D.; Majeski, R.; Zarnstorff, M.

    2008-01-18

    The National Compact Stellarator Experiment (NCSX) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral beam injection, and radio-frequency (rf). Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, neutral beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The experimental plan requires 3 MW of 50-keV balanced neutral beam tangential injection with pulse lengths of 500 ms for initial experiments, to be upgradeable to pulse lengths of 1.5 s. Subsequent upgrades will add 3MW of neutral beam injection (NBI). This paper discusses the NCSX NBI requirements and design issues and shows how these are provided by the candidate PBX-M NBI system. In addition, estimations are given for beam heating efficiencies, scaling of heating efficiency with machine size and magnetic field level, parameter studies of the optimum beam injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of rf heating by mode conversion ion Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron cyclotron heating. The initial MCIBW heating technique and the design of the rf system lend themselves to current drive, so if current drive became desirable for any reason, only minor modifications to the heating system described here would be needed. The rf system will also be capable of localized ion heating (bulk or tail), and possiblyIBW-generated sheared flows.

  5. 5 MW 805 MHz SNS RF System Experience

    CERN Document Server

    Young, Karen A; Hardek, Thomas; Lynch, Michael; Rees, Daniel; Roybal, William; Tallerico, Paul J; Thomas Bradley, Joseph

    2005-01-01

    The RF system for the 805 MHz normal conducting linac of the Spallation Nuetron Source (SNS) accelerator was designed, procured and tested at Los Alamos National Laboratory(LANL) and then installed and commissioned at Oak Ridge National Laboratory (ORNL). The RF power for this room temperature coupled cavity linac (CCL) of SNS accelerator is generated by four pulsed 5 MW peak power klystrons operating with a pulse width of 1.25 mSec and a 60 Hz repetition frequency. The RF power from each klystron is divided and delivered to the CCL through two separate RF windows. The 5 MW RF system advanced the state of the art for simultaneous peak and average power. This paper summarizes the problems encountered, lessons learned and results of the high power testing at LANL of the 5 MW klystrons, 5 MW circulators, 5 MW loads, and 2.5 MW windows.*

  6. 15 MW HArdware-in-the-loop Grid Simulation Project

    Energy Technology Data Exchange (ETDEWEB)

    Rigas, Nikolaos [Clemson Univ., SC (United States); Fox, John Curtiss [Clemson Univ., SC (United States); Collins, Randy [Clemson Univ., SC (United States); Tuten, James [Clemson Univ., SC (United States); Salem, Thomas [Clemson Univ., SC (United States); McKinney, Mark [Clemson Univ., SC (United States); Hadidi, Ramtin [Clemson Univ., SC (United States); Gislason, Benjamin [Clemson Univ., SC (United States); Boessneck, Eric [Clemson Univ., SC (United States); Leonard, Jesse [Clemson Univ., SC (United States)

    2014-10-31

    The 15MW Hardware-in-the-loop (HIL) Grid Simulator project was to (1) design, (2) construct and (3) commission a state-of-the-art grid integration testing facility for testing of multi-megawatt devices through a ‘shared facility’ model open to all innovators to promote the rapid introduction of new technology in the energy market to lower the cost of energy delivered. The 15 MW HIL Grid Simulator project now serves as the cornerstone of the Duke Energy Electric Grid Research, Innovation and Development (eGRID) Center. This project leveraged the 24 kV utility interconnection and electrical infrastructure of the US DOE EERE funded WTDTF project at the Clemson University Restoration Institute in North Charleston, SC. Additionally, the project has spurred interest from other technology sectors, including large PV inverter and energy storage testing and several leading edge research proposals dealing with smart grid technologies, grid modernization and grid cyber security. The key components of the project are the power amplifier units capable of providing up to 20MW of defined power to the research grid. The project has also developed a one of a kind solution to performing fault ride-through testing by combining a reactive divider network and a large power converter into a hybrid method. This unique hybrid method of performing fault ride-through analysis will allow for the research team at the eGRID Center to investigate the complex differences between the alternative methods of performing fault ride-through evaluations and will ultimately further the science behind this testing. With the final goal of being able to perform HIL experiments and demonstration projects, the eGRID team undertook a significant challenge with respect to developing a control system that is capable of communicating with several different pieces of equipment with different communication protocols in real-time. The eGRID team developed a custom fiber optical network that is based upon FPGA

  7. Independent Research and Design of 600-MW Supercritical CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In order to further develop and improve the technologies for large-capacity supercritical CFB boiler, the key technologies for large CFB boiler were systematically studied, based on the development of first domestically-made 210-MW and 330-MW CFB boilers. The scheme of 600-MW supercritical CFB boiler was designed, including the furnace structure, key components, steam-water system and auxiliary systems, which laid a technical foundation for the engineering applications.

  8. CO{sub 2} reduction: potential of heat pumps when used together with combined heat and power units; Potentiel energetique des pompes a chaleur combinees au couplage chaleur-force. Pour une reduction maximale des emissions de CO{sub 2} et pour une production de courant fossile avec reduction des emissions de CO{sub 2} en Suisse - Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    Rognon, F.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the potential of using heat pumps in combination with Combined Heat and Power (CHP) units as a replacement for fossil-fuel fired heating units in Switzerland. The electrical power produced by the CHP units can be used to provide power for the drives of heat pump systems. The author states that the fossil fuel consumption and the resulting emissions of carbon dioxide can be halved using this combination. Also, even more efficient systems using power produced in larger combined-cycle power generation are discussed. Further examples of how fossil-fired power generation in combination with heat pumps can not only replace fossil-fuelled heating systems but also provide additional electricity too are given. This overview includes figures on the potential of such combined systems.

  9. Computational heat transfer analysis and combined ANN–GA optimization of hollow cylindrical pin fin on a vertical base plate

    Indian Academy of Sciences (India)

    C Balachandar; S Arunkumar; M Venkatesan

    2015-09-01

    In the devices like laptops, microprocessors, the electric circuits generate heat while performing work which necessitates the use of fins. In the present work, the heat transfer characteristics of hollow cylindrical pin fin array on a vertical rectangular base plate is studied using commercial CFD code ANSYS FLUENT© . The hollow cylindrical pin fins are arranged inline. The heat transfer augmentation is studied for different parameters such as inner radius, outer radius, height of the fins and number of pin fins. The base plate is supplied with a constant heat flux in the range of 20–500W. The base plate dimensions are kept constant. The base plate temperature is predicted using Artificial Neural Network (ANN) by training the network based on the results of numerical simulation. The trained ANN is used to analyse the fin in terms of enhanced heat transfer and weight reduction when compared to solid pin fin. Optimization of the hollow cylindrical pin fin parameters to obtain maximum heat transfer from the base plate is carried out using Genetic Algorithm (GA) applied on the trained neural network. The analysis using the numerical simulation and neural network shows that the hollow fins provide an increased heat transfer and a weight reduction of about 90% when compared to solid cylindrical pin fins.

  10. Combined natural convection and mass transfer effects on unsteady flow past an infinite vertical porous plate embedded in a porous medium with heat source

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.S. [Department of Physics, K B D A V College, Nirakarpur, Khurda-752 019 (Orissa) (India); Tripathy, R.K. [Department of Physics, D R Nayapalli College, Bhubaneswar-751 012 (Orissa) (India); Padhy, R.K. [Department of Physics, D A V Public School, Chandrasekharpur, Bhubaneswar-751 021 (Orissa) (India); Sahu, M. [Department of Physics, Jupiter +2 Women’s Science College, IRC Village, Bhubaneswar-751 015 (Orissa) (India)

    2012-07-01

    This paper theoretically investigates the combined natural convection and mass transfer effects on unsteady flow of a viscous incompressible fluid past an infinite vertical porous plate embedded in a porous medium with heat source. The governing equations of the flow field are solved analytically for velocity, temperature, concentration distribution, skin friction and the rate of heat transfer using multi parameter perturbation technique and the effects of the flow parameters such as permeability parameter Kp, Grashof number for heat and mass transfer Gr, Gc; heat source parameter S, Schmidt number Sc, Prandtl number Pr etc. on the flow field are analyzed and discussed with the help of figures and tables. The permeability parameter Kp is reported to accelerate the transient velocity of the flow field at all points for small values of Kp (£1) and for higher values the effect reverses. The effect of increasing Grashof numbers for heat and mass transfer or heat source parameter is to enhance the transient velocity of the flow field at all points while a growing Schmidt number retards its effect at all points. A growing permeability parameter or heat source parameter increases the transient temperature of the flow field at all points, while a growing Prandtl number shows reverse effect. The effect of increasing Schmidt number is to decrease the concentration boundary layer thickness of the flow field at all points. Further, a growing permeability parameter enhances the skin friction at the wall and a growing Prandtl number shows reverse effect. The effect of increasing Prandtl number or permeability parameter leads to increase the magnitude of the rate of heat transfer at the wall.

  11. Combined natural convection and mass transfer effects on unsteady flow past an infinite vertical porous plate embedded in a porous medium with heat source

    Directory of Open Access Journals (Sweden)

    S. S. Das, R. K. Tripathy, R. K. Padhy, M. Sahu

    2012-01-01

    Full Text Available This paper theoretically investigates the combined natural convection and mass transfer effects on unsteady flow of a viscous incompressible fluid past an infinite vertical porous plate embedded in a porous medium with heat source. The governing equations of the flow field are solved analytically for velocity, temperature, concentration distribution, skin friction and the rate of heat transfer using multi parameter perturbation technique and the effects of the flow parameters such as permeability parameter Kp, Grashof number for heat and mass transfer Gr, Gc; heat source parameter S, Schmidt number Sc, Prandtl number Pr etc. on the flow field are analyzed and discussed with the help of figures and tables. The permeability parameter Kp is reported to accelerate the transient velocity of the flow field at all points for small values of Kp (less than or equal 1 and for higher values the effect reverses. The effect of increasing Grashof numbers for heat and mass transfer or heat source parameter is to enhance the transient velocity of the flow field at all points while a growing Schmidt number retards its effect at all points. A growing permeability parameter or heat source parameter increases the transient temperature of the flow field at all points, while a growing Prandtl number shows reverse effect. The effect of increasing Schmidt number is to decrease the concentration boundary layer thickness of the flow field at all points. Further, a growing permeability parameter enhances the skin friction at the wall and a growing Prandtl number shows reverse effect. The effect of increasing Prandtl number or permeability parameter leads to increase the magnitude of the rate of heat transfer at the wall.

  12. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    David, Andrei; Mathiesen, Brian Vad; Averfalk, Helge

    2017-01-01

    The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document...... capacity of electric large-scale heat pumps with more than 1 MW thermal output, operating in European DH systems. The survey is the first database of its kind containing the technical characteristics of these heat pumps, and provides the basis for the analysis of this paper. By quantifying the heat sources...... that such developments can begin now with technologies currently available. We present a database and the status of the technology and its ability of expansion to other European locations by reviewing experiences aimed at further research or application in the heating industry. This is based on a survey of the existing...

  13. Surface heat flow and CO2 emissions within the Ohaaki hydrothermal field, Taupo Volcanic Zone, New Zealand

    Science.gov (United States)

    Rissmann, C.; Christenson, B.; Werner, C.; Leybourne, M.; Cole, J.; Gravley, D.

    2012-01-01

    Carbon dioxide emissions and heat flow have been determined from the Ohaaki hydrothermal field, Taupo Volcanic Zone (TVZ), New Zealand following 20a of production (116MW e). Soil CO2 degassing was quantified with 2663 CO2 flux measurements using the accumulation chamber method, and 2563 soil temperatures were measured and converted to equivalent heat flow (Wm -2) using published soil temperature heat flow functions. Both CO2 flux and heat flow were analysed statistically and then modelled using 500 sequential Gaussian simulations. Forty subsoil CO 2 gas samples were also analysed for stable C isotopes. Following 20a of production, current CO2 emissions equated to 111??6.7T/d. Observed heat flow was 70??6.4MW, compared with a pre-production value of 122MW. This 52MW reduction in surface heat flow is due to production-induced drying up of all alkali-Cl outflows (61.5MW) and steam-heated pools (8.6MW) within the Ohaaki West thermal area (OHW). The drying up of all alkali-Cl outflows at Ohaaki means that the soil zone is now the major natural pathway of heat release from the high-temperature reservoir. On the other hand, a net gain in thermal ground heat flow of 18MW (from 25MW to 43.3??5MW) at OHW is associated with permeability increases resulting from surface unit fracturing by production-induced ground subsidence. The Ohaaki East (OHE) thermal area showed no change in distribution of shallow and deep soil temperature contours despite 20a of production, with an observed heat flow of 26.7??3MW and a CO 2 emission rate of 39??3T/d. The negligible change in the thermal status of the OHE thermal area is attributed to the low permeability of the reservoir beneath this area, which has limited production (mass extraction) and sheltered the area from the pressure decline within the main reservoir. Chemistry suggests that although alkali-Cl outflows once contributed significantly to the natural surface heat flow (~50%) they contributed little (99% of the original CO 2

  14. Development of a 5 MW reference gearbox for offshore wind turbines: 5 MW reference gearbox

    Energy Technology Data Exchange (ETDEWEB)

    Nejad, Amir Rasekhi [Norwegian Research Center for Offshore Wind Technology, Norwegian University of Science and Technology, Trondheim Norway; Center for Ships and Ocean Structures, Norwegian University of Science and Technology, Trondheim Norway; Guo, Yi [National Wind Technology Center, National Renewable Energy Laboratory, Golden Colorado USA; Gao, Zhen [Center for Ships and Ocean Structures, Norwegian University of Science and Technology, Trondheim Norway; Moan, Torgeir [Norwegian Research Center for Offshore Wind Technology, Norwegian University of Science and Technology, Trondheim Norway; Center for Ships and Ocean Structures, Norwegian University of Science and Technology, Trondheim Norway

    2015-07-27

    This paper presents detailed descriptions, modeling parameters and technical data of a 5MW high-speed gearbox developed for the National Renewable Energy Laboratory offshore 5MW baseline wind turbine. The main aim of this paper is to support the concept studies and research for large offshore wind turbines by providing a baseline gearbox model with detailed modeling parameters. This baseline gearbox follows the most conventional design types of those used in wind turbines. It is based on the four-point supports: two main bearings and two torque arms. The gearbox consists of three stages: two planetary and one parallel stage gears. The gear ratios among the stages are calculated in a way to obtain the minimum gearbox weight. The gearbox components are designed and selected based on the offshore wind turbine design codes and validated by comparison to the data available from large offshore wind turbine prototypes. All parameters required to establish the dynamic model of the gearbox are then provided. Moreover, a maintenance map indicating components with high to low probability of failure is shown. The 5 MW reference gearbox can be used as a baseline for research on wind turbine gearboxes and comparison studies. It can also be employed in global analysis tools to represent a more realistic model of a gearbox in a coupled analysis.

  15. Combined Active and Passive Solar Space Heating and Solar Hot Water Systems for an Elementary School in Boise, Idaho.

    Science.gov (United States)

    Smull, Neil A.; Armstrong, Gerald L.

    1979-01-01

    Amity Elementary School in Boise, Idaho, features a solar space heating and domestic hot water system along with an earth covering to accommodate the passive aspects of energy conservation. (Author/MLF)

  16. Experimental Study of Air Distribution and Ventilation Effectiveness in a Room with a Combination of Different Mechanical Ventilation and Heating/Cooling Systems

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.; Simone, Angela; Krajcik, Michal;

    2011-01-01

    Mixing and displacement ventilation are common systems in commercial buildings, while mixing ventilation is used in residential buildings. Displacement ventilation provides fresh air to the occupied zone in a more efficient way than mixing ventilation but it is important to know how well it works...... with a floor system for heating or cooling. Can, for example, a floor heating system warm up the supply air too fast and destroy the displacement effect? Will floor cooling, combined with displacement ventilation, result in too high a vertical temperature difference and too low a temperature at feet level......? The required amount of ventilation depends on the ventilation effectiveness. In standards, the recommended values for ventilation effectiveness depend on the position of the supply and exhaust device and on the difference between supply and room air temperature. Among others, for warm air heating...

  17. Improvement of xenon purification system using a combination of a pulse tube refrigerator and a coaxial heat exchanger

    CERN Document Server

    Chen, Wan-Ting; Cussonneau, J -P; Donnard, J; Duval, S; Lemaire, O; Calloch, M Le; Ray, P Le; Mohamad-Hadi, A -F; Morteau, E; Oger, T; Scotto-Lavina, L; Stutzmann, J -S; Thers, D; Briend, P; Haruyama, T; Mihara, S; Tauchi, T

    2012-01-01

    We have developed a compact cryogenic system with a pulse tube refrigerator and a coaxial heat exchanger. This liquefaction-purification system not only saves the cooling power used to reach high gaseous recirculation rate, but also reduces the impurity level with high speed. The heat exchanger operates with an efficiency of 99%, which indicates the possibility for fast xenon gas recirculation in a highpressurized large-scale xenon storage with much less thermal losses.

  18. Compact heat exchanger for power plants; Kompakti siirrin tyoentyy myoes kotimaan voimalaitoksiin

    Energy Technology Data Exchange (ETDEWEB)

    Kinnunen, L. [Energia-lehti, Helsinki (Finland)

    2001-07-01

    Vahterus Oy, located at Kalanti, has manufactured heat exchangers since the beginning of 1990s. About 90% of the equipment produced are exported. In the PSHE (Plate and Shell) solution of the Vahterus heat exchanger the heat is transferred by round plated welded to form a compact package, which is assembled into a cylindrical steel casing. The heat exchanger contains no gaskets or soldered joints, which eliminates the leak risks. Traditional heat exchanges are usually operated at higher temperatures and pressures, but the heat transfer capacities of them are lower. Plate heat exchangers, on the other hand, are efficient, but the application range of them is narrow. Additionally, the rubber gasket of the heat exchange plates, sealing the joints of the heat exchanging plates, does not stand high pressures or temperatures, or corroding fluids. The new welded plate heat exchanger combine the pressure and temperature resistance of tube heat exchangers and the high heat exchange capacity of plate heat exchangers. The new corrosion resisting heat exchanger can be applied for especially hard conditions. The operating temperature range of the PSHE heat exchanger is - 200 - 900 deg C. The pressure resistance is as high as 100 bar. The space requirement of PSHE is only one tenth of the space requirement of traditional tube heat exchangers. Adjusting the number of heat exchanging plates can change the capacity of the heat exchanger. Power range of the heat exchanger can be as high as 80 MW. Due to the corrosion preventive construction and the small dimension the PSHE heat exchanger can be applied for refrigerators using ammonia as refrigerant. These kinds of new Vahterus heat exchangers are in use in 60 countries in more than 2000 refrigerators.

  19. Periodic Unsteady Flow Aerodynamics and Heat Transfer: Studies on a Curved Surface, Combined Part I and II

    Directory of Open Access Journals (Sweden)

    M. T. Schobeiri

    2000-01-01

    Full Text Available Aerodynamic and heat transfer investigations were done on a constant curvature curved plate in a subsonic wind tunnel facility for various wake passing frequencies and zero pressure gradient conditions. Steady and unsteady boundary layer transition measurements were taken on the concave surface of the curved plate at different wake passing frequencies where a rotating squirrel-cage generated the unsteady wake flow. The data were analyzed using timeaveraged and ensemble-averaged techniques to provide insight into the growth of the boundary layer and transition. Ensemble-averaged turbulence intensity contours in the temporal spatial domain showed that transition was induced for increasing wake passing frequency and structure. The local heat transfer coefficient distribution for the concave and convex surface was determined at those wake passing frequencies using a liquid crystal heat transfer measurement technique. Detailed aerodynamic and heat transfer investigations showed that higher wake passing frequency caused transition to occur earlier on the concave surface. Local Stanton numbers were also calculated on the concave surface and compared with Stanton numbers predicted using a differential boundary layer and heat transfer calculation method. On the convex side, no effect of wake passing frequency on heat transfer was observed due to a separation bubble that induced transition.

  20. Comparative analysis of cooling systems for energy equipment of combined heat and power plants and nuclear power plants

    Science.gov (United States)

    Reutov, B. F.; Lazarev, M. V.; Ermakova, S. V.; Zisman, S. L.; Kaplanovich, L. S.; Svetushkov, V. V.

    2016-07-01

    In the 20th century, the thermal power engineering in this country was oriented toward oncethrough cooling systems. More than 50% of the CHPP and NPP capacities with once-through cooling systems put into operation before the 1990s were large-scale water consumers but with minimum irretrievable water consumption. In 1995, the Water Code of the Russian Federation was adopted in which restrictions on application of once-through cooling systems for newly designed combined heat and power plants (CHPPs) were introduced for the first time. A ban on application of once-through systems was imposed by the current Water Code of the Russian Federation (Federal law no. 74-FZ, Art. 60 Cl. 4) not only for new CHPPs but also for those to be modified. Clause 4 of Article 60 of the Water Code of the Russian Federation contravenes law no. 7-FZ "On Protection of the Environment" that has priority significance, since the water environment is only part of the natural environment and those articles of the Water Code of the Russian Federation that are related directly to electric power engineering, viz., Articles 46 and 62. In recent decades, the search for means to increase revenue charges and the economic pressure on the thermal power industry caused introduction by law of charges for use of water by cooling systems irrespective of the latter's impact on the water quality of the source, the environment, the economic efficiency of the power production, and the living conditions of the people. The long-range annual increase in the water use charges forces the power generating companies to switch transfer once-through service water supply installations to recirculating water supply systems and once-through-recirculating systems with multiple reuse of warm water, which drastically reduces the technical, economic, and ecological characteristic of the power plant operation and also results in increasing power rates for the population. This work comprehensively substantiates the demands of