WorldWideScience

Sample records for heat engine development

  1. Heat engine development for solar thermal power systems

    Science.gov (United States)

    Pham, H. Q.; Jaffe, L. D.

    The parabolic dish solar collector systems for converting sunlight to electrical power through a heat engine will, require a small heat engine of high performance long lifetime to be competitive with conventional power systems. The most promising engine candidates are Stirling, high temperature Brayton, and combined cycle. Engines available in the current market today do not meet these requirements. The development of Stirling and high temperature Brayton for automotive applications was studied which utilizes much of the technology developed in this automotive program for solar power engines. The technical status of the engine candidates is reviewed and the components that may additional development to meet solar thermal system requirements are identified.

  2. Advanced Materials Development Program: Ceramic Technology for Advanced Heat Engines program plan, 1983--1993

    Energy Technology Data Exchange (ETDEWEB)

    1990-07-01

    The purpose of the Ceramic Technology for Advanced Heat Engines (CTAHE) Project is the development of an industrial technology base capable of providing reliable and cost-effective high temperature ceramic components for application in advanced heat engines. There is a deliberate emphasis on industrial'' in the purpose statement. The project is intended to support the US ceramic and engine industries by providing the needed ceramic materials technology. The heat engine programs have goals of component development and proof-of-concept. The CTAHE Project is aimed at developing generic basic ceramic technology and does not involve specific engine designs and components. The materials research and development efforts in the CTAHE Project are focused on the needs and general requirements of the advanced gas turbine and low heat rejection diesel engines. The CTAHE Project supports the DOE Office of Transportation Systems' heat engine programs, Advanced Turbine Technology Applications (ATTAP) and Heavy Duty Transport (HDT) by providing the basic technology required for development of reliable and cost-effective ceramic components. The heat engine programs provide the iterative component design, fabrication, and test development logic. 103 refs., 18 figs., 11 tabs.

  3. Development and test of combustion chamber for Stirling engine heated by natural gas

    Science.gov (United States)

    Li, Tie; Song, Xiange; Gui, Xiaohong; Tang, Dawei; Li, Zhigang; Cao, Wenyu

    2014-04-01

    The combustion chamber is an important component for the Stirling engine heated by natural gas. In the paper, we develop a combustion chamber for the Stirling engine which aims to generate 3˜5 kWe electric power. The combustion chamber includes three main components: combustion module, heat exchange cavity and thermal head. Its feature is that the structure can divide "combustion" process and "heat transfer" process into two apparent individual steps and make them happen one by one. Since natural gas can mix with air fully before burning, the combustion process can be easily completed without the second wind. The flame can avoid contacting the thermal head of Stirling engine, and the temperature fields can be easily controlled. The designed combustion chamber is manufactured and its performance is tested by an experiment which includes two steps. The experimental result of the first step proves that the mixture of air and natural gas can be easily ignited and the flame burns stably. In the second step of experiment, the combustion heat flux can reach 20 kW, and the energy utilization efficiency of thermal head has exceeded 0.5. These test results show that the thermal performance of combustion chamber has reached the design goal. The designed combustion chamber can be applied to a real Stirling engine heated by natural gas which is to generate 3˜5 kWe electric power.

  4. Irreversible Brownian Heat Engine

    Science.gov (United States)

    Taye, Mesfin Asfaw

    2017-10-01

    We model a Brownian heat engine as a Brownian particle that hops in a periodic ratchet potential where the ratchet potential is coupled with a linearly decreasing background temperature. We show that the efficiency of such Brownian heat engine approaches the efficiency of endoreversible engine η =1-√{{Tc/Th}} [23]. On the other hand, the maximum power efficiency of the engine approaches η ^{MAX}=1-({Tc/Th})^{1\\over 4}. It is shown that the optimized efficiency always lies between the efficiency at quasistatic limit and the efficiency at maximum power while the efficiency at maximum power is always less than the optimized efficiency since the fast motion of the particle comes at the expense of the energy cost. If the heat exchange at the boundary of the heat baths is included, we show that such a Brownian heat engine has a higher performance when acting as a refrigerator than when operating as a device subjected to a piecewise constant temperature. The role of time on the performance of the motor is also explored via numerical simulations. Our numerical results depict that the time t and the external load dictate the direction of the particle velocity. Moreover, the performance of the heat engine improves with time. At large t (steady state), the velocity, the efficiency and the coefficient of performance of the refrigerator attain their maximum value. Furthermore, we study the effect of temperature by considering a viscous friction that decreases exponentially as the background temperature increases. Our result depicts that the Brownian particle exhibits a fast unidirectional motion when the viscous friction is temperature dependent than that of constant viscous friction. Moreover, the efficiency of this motor is considerably enhanced when the viscous friction is temperature dependent. On the hand, the motor exhibits a higher performance of the refrigerator when the viscous friction is taken to be constant.

  5. Development of Advanced In-Cylinder Components and Tribological Systems for Low Heat Rejection Diesel Engines

    Science.gov (United States)

    Yonushonis, T. M.; Wiczynski, P. D.; Myers, M. R.; Anderson, D. D.; McDonald, A. C.; Weber, H. G.; Richardson, D. E.; Stafford, R. J.; Naylor, M. G.

    1999-01-01

    In-cylinder components and tribological system concepts were designed, fabricated and tested at conditions anticipated for a 55% thermal efficiency heavy duty diesel engine for the year 2000 and beyond. A Cummins L10 single cylinder research engine was used to evaluate a spherical joint piston and connecting rod with 19.3 MPa (2800 psi) peak cylinder pressure capability, a thermal fatigue resistant insulated cylinder head, radial combustion seal cylinder liners, a highly compliant steel top compression ring, a variable geometry turbocharger, and a microwave heated particulate trap. Components successfully demonstrated in the final test included spherical joint connecting rod with a fiber reinforced piston, high conformability steel top rings with wear resistant coatings, ceramic exhaust ports with strategic oil cooling and radial combustion seal cylinder liner with cooling jacket transfer fins. A Cummins 6B diesel was used to develop the analytical methods, materials, manufacturing technology and engine components for lighter weight diesel engines without sacrificing performance or durability. A 6B diesel engine was built and tested to calibrate analytical models for the aluminum cylinder head and aluminum block.

  6. Shape memory heat engines

    Science.gov (United States)

    Salzbrenner, R.

    1984-06-01

    The mechanical shape memory effect associated with a thermoelastic martensitic transformation can be used to convert heat directly into mechanical work. Laboratory simulation of two types of heat engine cycles (Stirling and Ericsson) has been performed to measure the amount of work available/cycle in a Ni-45 at. pct Ti alloy. Tensile deformations at ambient temperature induced martensite, while a subsequent increase in temperature caused a reversion to the parent phase during which a load was carried through the strain recovery (i.e., work was accomplished). The amount of heat necessary to carry the engines through a cycle was estimated from calorimeter measurements and the work performed/cycle. The measured efficiency of the system tested reached a maximum of 1.4 percent, which was well below the theoretical (Carnot) maximum efficiency of 35.6 percent.

  7. Development of thermoacoustic engine operating by waste heat from cooking stove

    Science.gov (United States)

    Chen, B. M.; Abakr, Y. A.; Riley, P. H.; Hann, D. B.

    2012-06-01

    There are about 1.5 billion people worldwide use biomass as their primary form of energy in household cooking[1]. They do not have access to electricity, and are too remote to benefit from grid electrical supply. In many rural communities, stoves are made without technical advancements, mostly using open fires cooking stoves which have been proven to be extremely low efficiency, and about 93% of the energy generated is lost during cooking. The cooking is done inside a dwelling and creates significant health hazard to the family members and pollution to environment. SCORE (www.score.uk.com) is an international collaboration research project to design and build a low-cost, high efficiency woodstove that uses about half amount of the wood of an open wood fire, and uses the waste heat of the stove to power a thermoacoustic engine (TAE) to produce electricity for applications such as LED lighting, charging mobile phones or charging a 12V battery. This paper reviews on the development of two types of the thermoacoustic engine powered by waste heat from cooking stove which is either using Propane gas or burning of wood as a cooking energy to produce an acceptable amount of electricity for the use of rural communities.

  8. Acoustical heat pumping engine

    Science.gov (United States)

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1983-08-16

    The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium. 2 figs.

  9. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    Directory of Open Access Journals (Sweden)

    Kalomba Mboyi

    2015-04-01

    Full Text Available A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the emitting material with the radioisotope decay heat and by powering the different valves of the plasma rocket engine with the same radioisotope decay heat using a radioisotope thermoelectric generator. This rocket engine is then benchmarked against a 1 N hydrazine thruster configuration operated on one of the Pleiades-HR-1 constellation spacecraft. A maximal specific impulse and power saving of respectively 529 s and 32% are achieved with helium as propellant. Its advantages are its power saving capability, high specific impulses and simultaneous ease of storage and restart. It can however be extremely voluminous and potentially hazardous. The Kabila rocket is found to bring great benefits to the existing spacecraft and further research should optimize its geometric characteristics and investigate the physical principals of its operation.

  10. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan

    2014-01-01

    ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

  11. Development of micro-engineered textured tungsten surfaces for high heat flux applications

    Energy Technology Data Exchange (ETDEWEB)

    Sharafat, Shahram, E-mail: shahrams@ucla.edu [University of California Los Angeles, CA (United States); Aoyama, Aaron [University of California Los Angeles, CA (United States); Williams, Brian, E-mail: brian.williams@ultramet.com [Ultramet Inc., Pacoima, CA (United States); Ghoniem, Nasr [University of California Los Angeles, CA (United States)

    2013-11-15

    Surface micro-engineering can enhance the thermo-mechanical performance of plasma facing components (PFCs). For example, castellation of a surface can reduce thermal stress due to high heat loads and thus provide higher thermo-mechanical resilience. Recently, fabrication of a variety of micro-sized refractory dendrites with reproducible geometric characteristics (e.g., density, length, height, and aspect ratio) has been demonstrated. In contrast to flat surfaces exposed to high heat loads, dendrites deform independently to minimize near-surface thermal stress, which results in improved thermo-mechanical performance. Thus, the use of dendrites offers a unique micro-engineering approach to enhance the performance of PFC structures. A brief overview of W, Re, and Mo dendritic structures is given along with micrographs that show dendrite-coated surfaces. The thermal responses of representative dendrite structures are analyzed as a function of aspect ratios and dendrite geometry. The heat-management capability of needle-like dendrites exposed to a surface energy of up to 1 MJ/m{sup 2} is analyzed and compared to a flat surface. It is concluded that dendrite structures can significantly reduce thermal stress in the substrate when compared to flat surfaces. Implications of dendritic surfaces on sputter erosion rates are also discussed briefly.

  12. Life explained by heat engines

    NARCIS (Netherlands)

    Muller, A.W.J.; Seckbach, J.

    2012-01-01

    Mitochondria are in essence fuel cells that use organics as reductant and oxygen as oxidant. In engineering, increasing attention is being given to the replacement of the internal combustion engine by the fuel cell. According to the Thermosynthesis theory, a similar replacement of heat engines by

  13. Identification of tribological research and development needs for lubrication of advanced heat engines

    Energy Technology Data Exchange (ETDEWEB)

    Fehrenbacher, L.L.; Levinson, T.M.

    1985-09-01

    The continuous evolution of higher power density propulsion systems has always fueled the search for materials and lubricants with improved thermal and/or durability characteristics. Tribology of the upper cylinder region is the major technology roadblock in the path of the adiabatic diesel engine which has an energy reduction potential that exceeds that of all other engine development types. This tribology assessment resulted in the following major conclusions: a low friction and a low wear seal between the ring belt and cylinder bore are the most critical tribology functions in the diesel combustion chamber; development of solid lubrication systems will not satisfy the simultaneous low friction and low wear requirements in the upper cylinder area; development of separate upper cylinder liquid lubrication systems offers the most attractive design alternative for meeting the operational goals of future ''minimum cooled'' diesel engines.

  14. Engineering heat transfer

    International Nuclear Information System (INIS)

    Welty, J.R.

    1974-01-01

    The basic concepts of heat transfer are covered with special emphasis on up-to-date techniques for formulating and solving problems in the field. The discussion progresses logically from phenomenology to problem solving, and treats numerical, integral, and graphical methods as well as traditional analytical ones. The book is unique in its thorough coverage of the fundamentals of numerical analysis appropriate to solving heat transfer problems. This coverage includes several complete and readable examples of numerical solutions, with discussions and interpretations of results. The book also contains an appendix that provides students with physical data for often-encountered materials. An index is included. (U.S.)

  15. Taub–Bolt heat engines

    Science.gov (United States)

    Johnson, Clifford V.

    2018-02-01

    It is shown that aspects of the extended thermodynamic properties of the Taub–Bolt–AdS spacetime in four dimensions are similar to those of the Schwarzschild–AdS black hole. In a high temperature expansion, the equations of state begin to deviate only at next-to-subleading orders. By analogy with what has been done for black holes, Taub–Bolt’s thermodynamic equations are used to define holographic heat engines, the first examples of gravitational heat engines defined using a spacetime that is not a black hole. As a further comparison, the Taub–Bolt engine efficiency is computed for two special kinds of engine cycle and compared to the results for analogous Schwarzschild black hole engine cycles.

  16. An adjustable Brownian heat engine

    International Nuclear Information System (INIS)

    Asfaw, Mesfin; Bekele, Mulugeta

    2002-09-01

    A microscopic heat engine is modeled as a Brownian particle in a sawtooth potential (with load) moving through a highly viscous medium driven by the thermal kick it gets from alternately placed hot and cold heat reservoirs. We found a closed form expression for the current as a function of the parameters characterizing the model. Depending on the values these model parameters take, the engine is also found to function as a refrigerator. Expressions for the efficiency as well as for the refrigerator performance are also reported. Study of how these quantities depend on the model parameters enabled us in identifying the points in the parameter space where the engine performs either with maximum power or with optimized efficiency. The corresponding efficiencies of the engine are then compared with those of the endoreversible and Carnot engines. (author)

  17. Surface engineering and heat treatment

    International Nuclear Information System (INIS)

    Morton, P.H.

    1991-01-01

    This book is the proceedings of a Conference organised jointly by The Institute of Metals and The Centre for Exploitation of Science and Technology (CEST). It sets out to review this role and point the way to the future by collecting together a series of invited papers written by noted authorities in their fields. The opening review by CEST highlights the economic and industrial importance of Surface Engineering and is followed by a group of four articles devoted to specific branches of industry. Several technical papers then describe various aspects of the development of heat treatment over the last twenty-five years. These are followed by papers describing advances made possible by new technologies such as plasma, laser and ion beam. A separate abstract has been prepared for a paper on materials aspects of ion beam technology. (author)

  18. Engineering heat transfer

    CERN Document Server

    Annaratone, Donatello

    2010-01-01

    This book is a generalist textbook; it is designed for anybody interested in heat transmission, including scholars, designers and students. Two criteria constitute the foundation of Annaratone's books, including the present one. The first one consists of indispensable scientific rigor without theoretical exasperation. The inclusion in the book of some theoretical studies, even if admirable for their scientific rigor, would have strengthened the scientific foundation of this publication, yet without providing the reader with further applicable know-how. The second criterion is to deliver practi

  19. Ceramic Technology for Advanced Heat Engines Project

    Energy Technology Data Exchange (ETDEWEB)

    1989-08-01

    The Ceramic Technology for Advanced Heat Engines Project was developed by the Department of Energy's Office of Transportation Systems (OTS) in Conservation and Renewable Energy. This project, part of the OTS's Advanced Materials Development Program, was developed to meet the ceramic technology requirements of the OTS's automotive technology programs. Significant accomplishments in fabricating ceramic components for the Department of Energy (DOE), National Aeronautics and Space Administration (NASA), and Department of Defense (DoD) advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially.

  20. Ceramic Technology For Advanced Heat Engines Project

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    Significant accomplishments in fabricating ceramic components for the Department of Energy (DOE), National Aeronautics and Space Administration (NASA), and Department of Defense (DoD) advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. The objective of the project is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. This advanced materials technology is being developed in parallel and close coordination with the ongoing DOE and industry proof of concept engine development programs. To facilitate the rapid transfer of this technology to U.S. industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. Abstracts prepared for appropriate papers.

  1. Ceramic Technology for Advanced Heat Engines Project

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    The Ceramic Technology For Advanced Heat Engines Project was developed by the Department of Energy's Office of Transportation Systems (OTS) in Conservation and Renewable Energy. This project, part of the OTS's Advanced Materials Development Program, was developed to meet the ceramic technology requirements of the OTS's automotive technology programs. Significant accomplishments in fabricating ceramic components for the Department of Energy (DOE), National Aeronautics and Space Administration (NASA), and Department of Defense (DOD) advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The objective of the project is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on structural ceramics for advanced gas turbine and diesel engines, ceramic hearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines.

  2. Development of the performance of an alpha-type heat engine by using elbow-bend transposed-fluids heat exchanger as a heater and a cooler

    Energy Technology Data Exchange (ETDEWEB)

    El-Ehwany, A.A.; Hennes, G.M. [Mechanical Power Department, Faculty of Engineering, Ain Shams University, 11566 Cairo (Egypt); Eid, E.I. [Mechanical Department, Faculty of Industrial Education, Suez Canal University, 43515 Suez (Egypt); El-Kenany, E.A. [Technological Development Department, Technological Studies Academy, Workers University, Tanta (Egypt)

    2011-02-15

    In this work, elbow-bend heat exchangers were suggested to be used as a heater and a cooler in an alpha-type Stirling engine. Elbow-bend heat exchanger is a bank of tubes arranged in a quadrant either in line or staggered with different normal and parallel pitches. Eight of such heat exchangers having different dimensions were tested experimentally for steady flow (in a previous work by the same authors). The experimental results were correlated for heat transfer and pressure drop. In the present work, an alpha-Stirling engine with twin parallel cylinders on a common crankcase was suggested to use elbow-bend heat exchangers as a heater and a cooler. In the heater, the flue gases flow inside the tubes and the working gas fluctuates about the heater tubes. In the cooler, the coolant flows inside the cooler tubes and the gas flows about the cooler tubes. A computer program in the form of a spread sheet was prepared to solve numerically the engine cycle in the vision of Schmidt theory. Upon calculations, the most suitable stroke/bore ratio, phase angle and speed were found out for nitrogen as a working gas. In a comparison among the proposed engine and practical ones by the literature, it was found that; the proposed engine delivers about 13% more power per cc per {delta}T than those by the literature at high thermal efficiency level. (author)

  3. Heat Pipes Reduce Engine-Exhaust Emissions

    Science.gov (United States)

    Schultz, D. F.

    1986-01-01

    Increased fuel vaporization raises engine efficiency. Heat-pipe technology increased efficiency of heat transfer beyond that obtained by metallic conduction. Resulted in both improved engine operation and reduction in fuel consumption. Raw material conservation through reduced dependence on strategic materials also benefit from this type of heat-pipe technology. Applications result in improved engine performance and cleaner environment.

  4. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  5. Performance of heat engines with non-zero heat capacity

    International Nuclear Information System (INIS)

    Odes, Ron; Kribus, Abraham

    2013-01-01

    Highlights: ► Finite heat capacity is a second irreversibility mechanism in addition to thermal resistance. ► Heat capacity introduces thermal transients and reverse heat flow. ► Engine maximum power and efficiency are lower for finite heat capacity. ► Implementing the optimal engine cycle requires active control. - Abstract: The performance of a heat engine is analyzed subject to two types of irreversibility: a non-zero heat capacity, together with the more common finite heat transfer rate between the engine and the external heat reservoirs. The heat capacity represents an engine body that undergoes significant temperature variations during the engine cycle. An option to cut off the heat exchange between the engine and the external surrounding for part of the engine cycle is also explored. A variational approach was taken to find the engine’s internal temperature profile (which defines the internal thermodynamic cycle) that would produce maximum power. The maximum power is shown to be lower than the case of zero heat capacity, due to a loss of heat that is stored in the engine body and then lost, bypassing the thermodynamic cycle. The maximum efficiency and the efficiency at maximum power are also lower than the zero heat capacity case. Similar to the Curzon–Ahlborn analysis, power can be traded for increased efficiency, but for high heat capacity, the range of efficiency that is available for such a trade is diminished. Isolating the engine during part of the cycle reduces maximum power, but the efficiency at maximum power and the maximum efficiency are improved, due to better exploitation of heat stored in the engine body. This might be useful for real engines that are limited by the internal energy change during a single engine cycle or by the operating frequency, leading to a broader power–efficiency curve.

  6. Development of a hot heat exchanger and a cleaning system for a 35 kW hermetic four cylinder Stirling engine for solid biomass fuels

    DEFF Research Database (Denmark)

    Carlsen, Henrik; Marinitsch, Gerald; Schöch, Martin

    2005-01-01

    been operated for more than 9,000 hours. Operating experiences gained from these plants formed the basis for the further development of this technology. The experiences showed that the efficiency of the Stirling hot gas heat exchanger and of the hot gas heat exchanger cleaning system have to be further...... optimised. Within the scope of a RD&D project, a new hot gas heat exchanger and a new cleaning system have been developed and optimised in cooperation of the AUSTRIAN BIOENERGY CENTRE GmbH, the Technical University of Denmark, MAWERA Holzfeuerungsanlagen GmbH, Austria, and BIOS BIOENERGIESYSTEME Gmb......H, Austria. The new design of the Stirling hot gas heat exchanger has been developed in order to optimise the performance of the engine and simplify the geometry. In this respect, an equal distribution of the heat transfer across each tube in the hot gas heat exchanger, the reduction of the internal Helium...

  7. 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.

  8. Effect of finite heat input on the power performance of micro heat engines

    International Nuclear Information System (INIS)

    Khu, Kerwin; Jiang, Liudi; Markvart, Tom

    2011-01-01

    Micro heat engines have attracted considerable interest in recent years for their potential exploitation as micro power sources in microsystems and portable devices. Thermodynamic modeling can predict the theoretical performance that can be potentially achieved by micro heat engine designs. An appropriate model can not only provide key information at the design stage but also indicate the potential room for improvement in existing micro heat engines. However, there are few models reported to date which are suitable for evaluating the power performance of micro heat engines. This paper presents a new thermodynamic model for determining the theoretical limit of power performance of micro heat engines with consideration to finite heat input and heat leakage. By matching the model components to those of a representative heat engine layout, the theoretical power, power density, and thermal efficiency achievable for a micro heat engine can be obtained for a given set of design parameters. The effects of key design parameters such as length and thermal conductivity of the engine material on these theoretical outputs are also investigated. Possible trade-offs among these performance objectives are discussed. Performance results derived from the developed model are compared with those of a working micro heat engine (P3) as an example. -- Highlights: → Thermodynamic model for micro heat engines. → Effect of different parameters on potential performance. → Tradeoffs for determining optimal size of micro engines.

  9. Ceramic technology for Advanced Heat Engines Project

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1991-07-01

    Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. This project is managed by ORNL for the Office of Transportation Technologies, Office of Transportation Materials, and is closely coordinated with complementary ceramics tasks funded by other DOE offices, NASA, DOD, and industry.

  10. Quantum dynamical framework for Brownian heat engines

    Science.gov (United States)

    Agarwal, G. S.; Chaturvedi, S.

    2013-07-01

    We present a self-contained formalism modeled after the Brownian motion of a quantum harmonic oscillator for describing the performance of microscopic Brownian heat engines such as Carnot, Stirling, and Otto engines. Our theory, besides reproducing the standard thermodynamics results in the steady state, enables us to study the role dissipation plays in determining the efficiency of Brownian heat engines under actual laboratory conditions. In particular, we analyze in detail the dynamics associated with decoupling a system in equilibrium with one bath and recoupling it to another bath and obtain exact analytical results, which are shown to have significant ramifications on the efficiencies of engines involving such a step. We also develop a simple yet powerful technique for computing corrections to the steady state results arising from finite operation time and use it to arrive at the thermodynamic complementarity relations for various operating conditions and also to compute the efficiencies of the three engines cited above at maximum power. Some of the methods and exactly solvable models presented here are interesting in their own right and could find useful applications in other contexts as well.

  11. Novikov Engine with Fluctuating Heat Bath Temperature

    Science.gov (United States)

    Schwalbe, Karsten; Hoffmann, Karl Heinz

    2018-04-01

    The Novikov engine is a model for heat engines that takes the irreversible character of heat fluxes into account. Using this model, the maximum power output as well as the corresponding efficiency of the heat engine can be deduced, leading to the well-known Curzon-Ahlborn efficiency. The classical model assumes constant heat bath temperatures, which is not a reasonable assumption in the case of fluctuating heat sources. Therefore, in this article the influence of stochastic fluctuations of the hot heat bath's temperature on the optimal performance measures is investigated. For this purpose, a Novikov engine with fluctuating heat bath temperature is considered. Doing so, a generalization of the Curzon-Ahlborn efficiency is found. The results can help to quantify how the distribution of fluctuating quantities affects the performance measures of power plants.

  12. Heat Exchanger Lab for Chemical Engineering Undergraduates

    Science.gov (United States)

    Rajala, Jonathan W.; Evans, Edward A.; Chase, George G.

    2015-01-01

    Third year chemical engineering undergraduate students at The University of Akron designed and fabricated a heat exchanger for a stirred tank as part of a Chemical Engineering Laboratory course. The heat exchanger portion of this course was three weeks of the fifteen week long semester. Students applied concepts of scale-up and dimensional…

  13. Advanced radioisotope heat source for Stirling Engines

    International Nuclear Information System (INIS)

    Dobry, T.J.; Walberg, G.

    2001-01-01

    The heat exchanger on a Stirling Engine requires a thermal energy transfer from a heat source to the engine through a very limited area on the heater head circumference. Designing an effective means to assure maximum transfer efficiency is challenging. A single General Purpose Heat Source (GPHS), which has been qualified for space operations, would satisfy thermal requirements for a single Stirling Engine that would produce 55 electrical watts. However, it is not efficient to transfer its thermal energy to the engine heat exchanger from its rectangular geometry. This paper describes a conceptual design of a heat source to improve energy transfer for Stirling Engines that may be deployed to power instrumentation on space missions

  14. Thermodynamic analysis of a new Marnoch Heat Engine

    International Nuclear Information System (INIS)

    Saneipoor, P.; Dincer, I.; Naterer, G.F.

    2013-01-01

    In this paper, recovery of waste heat from an industrial facility with a new Marnoch Heat Engine (MHE) is examined. The MHE can be operated with temperature differentials below 100 K. A flowing liquid transfers heat from the heat source into heat exchangers and then removes heat from cold heat exchangers. Compressed dry air is used as a working medium in the heat engine. In this paper, the mechanical configuration of the heat engine is presented and analyzed. A thermodynamic model is developed to study the performance of the heat engine under various operating conditions. The results show that the exergy efficiency of the MHE reaches up to 17%. The major sources of exergy loss are presented and discussed, in order to optimize the system performance. -- Highlights: ► To develop a thermodynamic model to study the performance of a Marnoch Heat Engine (MHE). ► To investigate the effects of changing operational conditions on the MHE's efficiency. ► To assess the application of the MHE's commercial viability

  15. Heat pipe development

    Science.gov (United States)

    Bienart, W. B.

    1973-01-01

    The objective of this program was to investigate analytically and experimentally the performance of heat pipes with composite wicks--specifically, those having pedestal arteries and screwthread circumferential grooves. An analytical model was developed to describe the effects of screwthreads and screen secondary wicks on the transport capability of the artery. The model describes the hydrodynamics of the circumferential flow in triangular grooves with azimuthally varying capillary menisci and liquid cross-sections. Normalized results were obtained which give the influence of evaporator heat flux on the axial heat transport capability of the arterial wick. In order to evaluate the priming behavior of composite wicks under actual load conditions, an 'inverted' glass heat pipe was designed and constructed. The results obtained from the analysis and from the tests with the glass heat pipe were applied to the OAO-C Level 5 heat pipe, and an improved correlation between predicted and measured evaporator and transport performance were obtained.

  16. Reliability of ceramics for heat engine applications

    Science.gov (United States)

    1980-01-01

    The advantages and disadvantages associated with the use of monolithic ceramics in heat engines are discussed. The principle gaps in the state of understanding of ceramic material, failure origins, nondestructive tests as well as life prediction are included.

  17. Stirling Engine With Radial Flow Heat Exchangers

    Science.gov (United States)

    Vitale, N.; Yarr, George

    1993-01-01

    Conflict between thermodynamical and structural requirements resolved. In Stirling engine of new cylindrical configuration, regenerator and acceptor and rejector heat exchangers channel flow of working gas in radial direction. Isotherms in regenerator ideally concentric cylinders, and gradient of temperature across regenerator radial rather than axial. Acceptor and rejector heat exchangers located radially inward and outward of regenerator, respectively. Enables substantial increase in power of engine without corresponding increase in diameter of pressure vessel.

  18. Engineering calculations in radiative heat transfer

    CERN Document Server

    Gray, W A; Hopkins, D W

    1974-01-01

    Engineering Calculations in Radiative Heat Transfer is a six-chapter book that first explains the basic principles of thermal radiation and direct radiative transfer. Total exchange of radiation within an enclosure containing an absorbing or non-absorbing medium is then described. Subsequent chapters detail the radiative heat transfer applications and measurement of radiation and temperature.

  19. Capture of Heat Energy from Diesel Engine Exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Chuen-Sen Lin

    2008-12-31

    Diesel generators produce waste heat as well as electrical power. About one-third of the fuel energy is released from the exhaust manifolds of the diesel engines and normally is not captured for useful applications. This project studied different waste heat applications that may effectively use the heat released from exhaust of Alaskan village diesel generators, selected the most desirable application, designed and fabricated a prototype for performance measurements, and evaluated the feasibility and economic impact of the selected application. Exhaust flow rate, composition, and temperature may affect the heat recovery system design and the amount of heat that is recoverable. In comparison with the other two parameters, the effect of exhaust composition may be less important due to the large air/fuel ratio for diesel engines. This project also compared heat content and qualities (i.e., temperatures) of exhaust for three types of fuel: conventional diesel, a synthetic diesel, and conventional diesel with a small amount of hydrogen. Another task of this project was the development of a computer-aided design tool for the economic analysis of selected exhaust heat recovery applications to any Alaskan village diesel generator set. The exhaust heat recovery application selected from this study was for heating. An exhaust heat recovery system was fabricated, and 350 hours of testing was conducted. Based on testing data, the exhaust heat recovery heating system showed insignificant effects on engine performance and maintenance requirements. From measurements, it was determined that the amount of heat recovered from the system was about 50% of the heat energy contained in the exhaust (heat contained in exhaust was evaluated based on environment temperature). The estimated payback time for 100% use of recovered heat would be less than 3 years at a fuel price of $3.50 per gallon, an interest rate of 10%, and an engine operation of 8 hours per day. Based on experimental data

  20. A Study of Ballast Water Treatment Using Engine Waste Heat

    Science.gov (United States)

    Balaji, Rajoo; Yaakob, Omar; Koh, Kho King; Adnan, Faizul Amri bin; Ismail, Nasrudin bin; Ahmad, Badruzzaman bin; Ismail, Mohd Arif bin

    2018-05-01

    Heat treatment of ballast water using engine waste heat can be an advantageous option complementing any proven technology. A treatment system was envisaged based on the ballast system of an existing, operational crude carrier. It was found that the available waste heat could raise the temperatures by 25 °C and voyage time requirements were found to be considerable between 7 and 12 days to heat the high volumes of ballast water. Further, a heat recovery of 14-33% of input energies from exhaust gases was recorded while using a test rig arrangement representing a shipboard arrangement. With laboratory level tests at temperature ranges of around 55-75 °C, almost complete species mortalities for representative phytoplankton, zooplankton and bacteria were observed while the time for exposure varied from 15 to 60 s. Based on the heat availability analyses for harvesting heat from the engine exhaust gases(vessel and test rig), heat exchanger designs were developed and optimized using Lagrangian method applying Bell-Delaware approaches. Heat exchanger designs were developed to suit test rig engines also. Based on these designs, heat exchanger and other equipment were procured and erected. The species' mortalities were tested in this mini-scale arrangement resembling the shipboard arrangement. The mortalities realized were > 95% with heat from jacket fresh water and exhaust gases alone. The viability of the system was thus validated.

  1. Efficiency bounds for nonequilibrium heat engines

    International Nuclear Information System (INIS)

    Mehta, Pankaj; Polkovnikov, Anatoli

    2013-01-01

    We analyze the efficiency of thermal engines (either quantum or classical) working with a single heat reservoir like an atmosphere. The engine first gets an energy intake, which can be done in an arbitrary nonequilibrium way e.g. combustion of fuel. Then the engine performs the work and returns to the initial state. We distinguish two general classes of engines where the working body first equilibrates within itself and then performs the work (ergodic engine) or when it performs the work before equilibrating (non-ergodic engine). We show that in both cases the second law of thermodynamics limits their efficiency. For ergodic engines we find a rigorous upper bound for the efficiency, which is strictly smaller than the equivalent Carnot efficiency. I.e. the Carnot efficiency can be never achieved in single reservoir heat engines. For non-ergodic engines the efficiency can be higher and can exceed the equilibrium Carnot bound. By extending the fundamental thermodynamic relation to nonequilibrium processes, we find a rigorous thermodynamic bound for the efficiency of both ergodic and non-ergodic engines and show that it is given by the relative entropy of the nonequilibrium and initial equilibrium distributions. These results suggest a new general strategy for designing more efficient engines. We illustrate our ideas by using simple examples. -- Highlights: ► Derived efficiency bounds for heat engines working with a single reservoir. ► Analyzed both ergodic and non-ergodic engines. ► Showed that non-ergodic engines can be more efficient. ► Extended fundamental thermodynamic relation to arbitrary nonequilibrium processes

  2. Heat engine driven by purely quantum information

    OpenAIRE

    Park, Jung Jun; Kim, Kang-Hwan; Sagawa, Takahiro; Kim, Sang Wook

    2013-01-01

    The key question of this paper is whether work can be extracted from a heat engine by using purely quantum mechanical information. If the answer is yes, what is its mathematical formula? First, by using a bipartite memory we show that the work extractable from a heat engine is bounded not only by the free energy change and the sum of the entropy change of an individual memory but also by the change of quantum mutual information contained inside the memory. We then find that the engine can be ...

  3. Development of a semi-empirical convective heat transfer correlation based on thermodynamic and optical measurements in a spark ignition engine

    International Nuclear Information System (INIS)

    Irimescu, Adrian; Merola, Simona Silvia; Tornatore, Cinzia; Valentino, Gerardo

    2015-01-01

    Highlights: • A new convective heat transfer correlation was developed for spark ignition engines. • Measurements in an experimental optical power unit were used for validation. • Fuel effects were correctly modeled and verified with methane and hydrogen. • Results were compared to two other widely used correlations. • Calibration was found to be easier for the proposed model. - Abstract: Internal combustion engines are still the main technology for energy conversion in automotive transport and are set to remain the main choice of propulsion solutions for some time to come. Development and design of these power units in the quest for improved efficiency and reduced environmental impact is increasingly reliant on simulations in order to reduce costs. Therefore, continuous improvement of sub-models used for numerical investigation is required so that correct and pertinent results are obtained. Convective heat transfer is receiving much attention in this respect, especially as direct injection spark ignition (DISI) engines can feature abnormal combustion phenomena such as mega-knock, mainly driven by local hot spots in the combustion chamber, that can be extremely damaging as they cannot be mitigated with existing control procedures. As a result, thermal stratification is more and more investigated through both quasi-dimensional and more complex computational fluid dynamics (CFD) codes. Alternative fuels are also extensively studied, especially as their specific properties that are different from those of gasoline can make their application challenging, thus requiring further insight in order to identify suitable injection and ignition control strategies. A new convective heat transfer correlation was developed for application in quasi-dimensional models, with a more fundamental basis combined with the application of a flow field model; results were compared to existing and extensively used empirical equations. Assessments were based on in-cylinder pressure

  4. Externally heated valve engine a new approach to piston engines

    CERN Document Server

    Kazimierski, Zbyszko

    2016-01-01

    This book reports on a novel approach for generating mechanical energy from different, external heat sources using the body of a typical piston engine with valves. By presenting simple yet effective numerical models, the authors show how this new approach, which combines existing internal combustion technology with a lubrication system, is able to offer an economic solution to the problem of mechanical energy generation in piston engines. Their results also show that a stable heat generation process can be guaranteed outside of the engine. The book offers a detailed report on physical and numerical models of 4-stroke and 2-stroke versions of the EHVE together with different models of heat exchange, valves and results of their simulations. It also delivers the test results of an engine prototype run in laboratory conditions. By presenting a novel theoretical framework and providing readers with extensive knowledge of both the advantages and challenges of the method, this book is expected to inspire academic re...

  5. Ceramic technology for advanced heat engines project

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    The Ceramic Technology for Advanced Heat Engines Project was developed by the Department of Energy's Office of Transportation Systems in Conservation and Renewable Energy. This project was developed to meet the ceramic technology requirements of the OTT's automotive technology programs. This project is managed by ORNL and is closely coordinated with complementary ceramics tasks funded by other DOE offices, NASA, DoD, and industry. Research is discussed under the following topics; Turbomilling of SiC Whiskers; microwave sintering of silicon nitride; and milling characterization; processing of monolithics; silicon nitride matrix; oxide matrix; silicate matrix; thermal and wear coatings; joining; design; contact interfaces; time-dependent behavior; environmental effects; fracture mechanics; nondestructive evaluation; and technology transfer. References, figures, and tables are included with each topic.

  6. Effect of different heat transfer models on HCCI engine simulation

    International Nuclear Information System (INIS)

    Neshat, Elaheh; Saray, Rahim Khoshbakhti

    2014-01-01

    Highlights: • A new multi zone model is developed for HCCI combustion modeling. • New heat transfer model is used for prediction of heat transfer in HCCI engines. • Model can predict engine combustion, performance and emission characteristics well. • Appropriate mass and heat transfer models cause to accurate prediction of CO, UHC and NOx. - Abstract: Heat transfer from engine walls has an important role on engine combustion, performance and emission characteristics. The main focus of this study is offering a new relation for calculation of convective heat transfer from in-cylinder charge to combustion chamber walls of HCCI engines and providing the ability of new model in comparison with the previous models. Therefore, a multi zone model is developed for homogeneous charge compression ignition engine simulation. Model consists of four different types of zones including core zone, boundary layer zone, outer zones, which are between core and boundary layer, and crevice zone. Conductive heat transfer and mass transfer are considered between neighboring zones. For accurate calculation of initial conditions at inlet valve closing, multi zone model is coupled with a single zone model, which simulates gas exchange process. Various correlations are used as convective heat transfer correlations. Woschni, modified Woschni, Hohenberg and Annand correlations are used as convective heat transfer models. The new convection model, developed by authors, is used, too. Comparative analyses are done to recognize the accurate correlation for prediction of engine combustion, performance and emission characteristics in a wide range of operating conditions. The results indicate that utilization of various heat transfer models, except for new convective heat transfer model, leads to significant differences in prediction of in-cylinder pressure and exhaust emissions. Using Woschni, Chang and new model, convective heat transfer coefficient increases near top dead center, sharply

  7. Fuel system for diesel engine with multi-stage heated

    Science.gov (United States)

    Ryzhov, Yu N.; Kuznetsov, Yu A.; Kolomeichenko, A. V.; Kuznetsov, I. S.; Solovyev, R. Yu; Sharifullin, S. N.

    2017-09-01

    The article describes a fuel system of a diesel engine with a construction tractor multistage heating, allowing the use of pure rapeseed oil as a diesel engine fuel. The paper identified the kinematic viscosity depending on the temperature and composition of the mixed fuel, supplemented by the existing recommendations on the use of mixed fuels based on vegetable oils and developed the device allowing use as fuel for diesel engines of biofuels based on vegetable oils.

  8. Analysis of pre-heated fuel combustion and heat-emission dynamics in a diesel engine

    Science.gov (United States)

    Plotnikov, S. A.; Kartashevich, A. N.; Buzikov, S. V.

    2018-01-01

    The article explores the feasibility of diesel fuel pre-heating. The research goal was to obtain and analyze the performance diagrams of a diesel engine fed with pre-heated fuel. The engine was tested in two modes: at rated RPMs and at maximum torque. To process the diagrams the authors used technique developed by the Central Diesel Research Institute (CDRI). The diesel engine’s heat emission curves were obtained. The authors concluded that fuel pre-heating shortened the initial phase of the combustion process and moderated the loads, thus making it possible to boost a diesel engine’s mean effective pressure.

  9. Heat pump heating with heat pumps driven by combustion engines or turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hein, K

    1977-01-27

    The heat pump described is driven by a gas Otto cycle engine, or a gas- or light- or heavy-oil fired Diesel engine. The claim refers to the use of waste heat of the engines by feeding into the input circuit of the heat pump. In addition, a drive by an electrical motor-generator or power production can be selected at times of peak load in the electrical supply network.

  10. Heat engine driven by purely quantum information.

    Science.gov (United States)

    Park, Jung Jun; Kim, Kang-Hwan; Sagawa, Takahiro; Kim, Sang Wook

    2013-12-06

    The key question of this Letter is whether work can be extracted from a heat engine by using purely quantum mechanical information. If the answer is yes, what is its mathematical formula? First, by using a bipartite memory we show that the work extractable from a heat engine is bounded not only by the free energy change and the sum of the entropy change of an individual memory but also by the change of quantum mutual information contained inside the memory. We then find that the engine can be driven by purely quantum information, expressed as the so-called quantum discord, forming a part of the quantum mutual information. To confirm it, as a physical example we present the Szilard engine containing a diatomic molecule with a semipermeable wall.

  11. Proceedings of the 1987 coatings for advanced heat engines workshop

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This Workshop was conducted to enhance communication among those involved in coating development for improved heat engine performance and durability. We were fortunate to have Bill Goward review the steady progress and problems encountered along the way in the use of thermal barrier coatings (TBC) in aircraft gas turbine engines. Navy contractors discussed their work toward the elusive goal of qualifying TBC for turbine airfoil applications. In the diesel community, Caterpillar and Cummins are developing TBC for combustion chamber components as part of the low heat rejection diesel engine concept. The diesel engine TBC work is based on gas turbine technology with a goal of more than twice the thickness used on gas turbine engine components. Adoption of TBC in production for diesel engines could justify a new generation of plasma spray coating equipment. Increasing interests in tribology were evident in this Workshop. Coatings have a significant role in reducing friction and wear under greater mechanical loadings at higher temperatures. The emergence of a high temperature synthetic lubricant could have an enormous impact on diesel engine design and operating conditions. The proven coating processes such as plasma spray, electron-beam physical vapor deposition, sputtering, and chemical vapor deposition have shown enhanced capabilities, particularly with microprocessor controls. Also, the newer coating schemes such as ion implantation and cathodic arc are demonstrating intriguing potential for engine applications. Coatings will play an expanding role in higher efficiency, more durable heat engines.

  12. Quantum heat engine with coupled superconducting resonators

    DEFF Research Database (Denmark)

    Hardal, Ali Ümit Cemal; Aslan, Nur; Wilson, C. M.

    2017-01-01

    We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one...... the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures....

  13. Problems of development and putting into education process an electronic textbook on special discipline 'General theory and construction of heat-and-power engineering facilities'

    International Nuclear Information System (INIS)

    Karitskaya, S.G.; Ruzanov, K.A.; Davletov, V.S.

    2005-01-01

    The results of work of making the electronic textbook of special discipline ('General theory and construction of heat-and-power engineering facilities' are brought. The principles and requirements, presented towards literature of such type, are outlined. (author)

  14. Reverse electrodialysis heat engine for sustainable power production

    International Nuclear Information System (INIS)

    Tamburini, A.; Tedesco, M.; Cipollina, A.; Micale, G.; Ciofalo, M.; Papapetrou, M.; Van Baak, W.; Piacentino, A.

    2017-01-01

    Graphical abstract: State of the art technologies for the conversion of heat into power. Grey circles refer to technologies at very early stage of development and non-available at industrial level. The Carnot efficiency (on the secondary horizontal axis) is evaluated assuming a cold sink temperature of 25 °C. SRC-hot gases: Steam Rankine Cycle integrated with gas turbine/other topping cycles; SRC-fuel: Steam Rankine Cycle directly fuelled by oil, coal or other fuels; KC: Kalina Cycle; ORC: Organic Rankine Cycle; TEG: Thermoelectric Generation; PEPG: Piezoelectric Power Generation with waste heat-powered expansion/compression cycle; OHE: Osmotic Heat Engine; REDHE, Reverse Electrodialysis Heat Engine (this paper). Display Omitted -- Highlights: •For the first time, the potential of Reverse Electrodialysis Heat Engine is assessed. •An overview of the possible regeneration methods is presented. •Performance of the RED unit fed by different salty solutions was suitably optimized. •Three different RED Heat Engine scenarios were studied. •Exergetic efficiency of about 85% could be achieved in the foreseen future. -- Abstract: Reverse Electrodialysis Heat Engine (REDHE) is a promising technology to convert waste heat at temperatures lower than 100 °C into electric power. In the present work an overview of the possible regeneration methods is presented and the technological challenges for the development of the RED Heat Engine (REDHE) are identified. The potential of this power production cycle was investigated through a simplified mathematical model. In the first part of the work, several salts were singularly modelled as possible solutes in aqueous solutions feeding the RED unit and the corresponding optimal conditions were recognized via an optimization study. In the second part, three different RED Heat Engine scenarios were studied. Results show that power densities much higher than those relevant to NaCl-water solutions can be obtained by using different

  15. Quantum heat engines and refrigerators: continuous devices.

    Science.gov (United States)

    Kosloff, Ronnie; Levy, Amikam

    2014-01-01

    Quantum thermodynamics supplies a consistent description of quantum heat engines and refrigerators up to a single few-level system coupled to the environment. Once the environment is split into three (a hot, cold, and work reservoir), a heat engine can operate. The device converts the positive gain into power, with the gain obtained from population inversion between the components of the device. Reversing the operation transforms the device into a quantum refrigerator. The quantum tricycle, a device connected by three external leads to three heat reservoirs, is used as a template for engines and refrigerators. The equation of motion for the heat currents and power can be derived from first principles. Only a global description of the coupling of the device to the reservoirs is consistent with the first and second laws of thermodynamics. Optimization of the devices leads to a balanced set of parameters in which the couplings to the three reservoirs are of the same order and the external driving field is in resonance. When analyzing refrigerators, one needs to devote special attention to a dynamical version of the third law of thermodynamics. Bounds on the rate of cooling when Tc→0 are obtained by optimizing the cooling current. All refrigerators as Tc→0 show universal behavior. The dynamical version of the third law imposes restrictions on the scaling as Tc→0 of the relaxation rate γc and heat capacity cV of the cold bath.

  16. Integrated Heat Exchange For Recuperation In Gas Turbine Engines

    Science.gov (United States)

    2016-12-01

    combustion engines conduct heat transfer in the exhaust system. The exhaust valves have hollow stems containing sodium, which act as heat pipes with...is the use of heat pipes in internal combustion engines . Internal combustion engines have combustion chambers with temperatures as high as 2700 K...accomplished using evaporative heat pipes . This study explores the feasibility of embedding this heat exchange system within engines using a

  17. Single-particle stochastic heat engine

    Science.gov (United States)

    Rana, Shubhashis; Pal, P. S.; Saha, Arnab; Jayannavar, A. M.

    2014-10-01

    We have performed an extensive analysis of a single-particle stochastic heat engine constructed by manipulating a Brownian particle in a time-dependent harmonic potential. The cycle consists of two isothermal steps at different temperatures and two adiabatic steps similar to that of a Carnot engine. The engine shows qualitative differences in inertial and overdamped regimes. All the thermodynamic quantities, including efficiency, exhibit strong fluctuations in a time periodic steady state. The fluctuations of stochastic efficiency dominate over the mean values even in the quasistatic regime. Interestingly, our system acts as an engine provided the temperature difference between the two reservoirs is greater than a finite critical value which in turn depends on the cycle time and other system parameters. This is supported by our analytical results carried out in the quasistatic regime. Our system works more reliably as an engine for large cycle times. By studying various model systems, we observe that the operational characteristics are model dependent. Our results clearly rule out any universal relation between efficiency at maximum power and temperature of the baths. We have also verified fluctuation relations for heat engines in time periodic steady state.

  18. Atmospheric Circulations of Rocky Planets as Heat Engines

    Science.gov (United States)

    Koll, D. D. B.

    2017-12-01

    Rocky planets are extremely common in the galaxy and include Earth, Mars, Venus, and hundreds of exoplanets. To understand and compare the climates of these planets, we need theories that are general enough to accommodate drastically different atmospheric and planetary properties. Unfortunately, few such theories currently exist.For Earth, there is a well-known principle that its atmosphere resembles a heat engine - the atmosphere absorbs heat near the surface, at a hot temperature, and emits heat to space in the upper troposphere, at a cold temperature, which allows it to perform work and balance dissipative processes such as friction. However, previous studies also showed that Earth's hydrological cycle uses up a large fraction of the heat engine's work output, which makes it difficult to view other atmospheres as heat engines.In this work I extend the heat engine principle from Earth towards other rocky planets. I explore both dry and moist atmospheres in an idealized general circulation model (GCM), and quantify their work output using entropy budgets. First, I show that convection and turbulent heat diffusion are important entropy sources in dry atmospheres. I develop a scaling that accounts for its effects, which allows me to predict the strength of frictional dissipation in dry atmospheres. There are strong parallels between my scaling and so-called potential intensity theory, which is a seminal theory for understanding tropical cyclones on Earth. Second, I address how moisture affects atmospheric heat engines. Moisture modifies both the thermodynamic properties of air and releases latent heat when water vapor condenses. I explore the impact of both effects, and use numerical simulations to explore the difference between dry and moist atmospheric circulations across a wide range of climates.

  19. Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces

    Science.gov (United States)

    Dussinger, Peter M.; Lindemuth, James E.

    1997-01-01

    The principal objective of this Phase 2 SBIR program was to develop and demonstrate a practically insoluble coating for nickel-based superalloys for Stirling engine heat pipe applications. Specific technical objectives of the program were: (1) Determine the solubility corrosion rates for Nickel 200, Inconel 718, and Udimet 72OLI in a simulated Stirling engine heat pipe environment, (2) Develop coating processes and techniques for capillary groove and screen wick structures, (3) Evaluate the durability and solubility corrosion rates for capillary groove and screen wick structures coated with an insoluble coating in cylindrical heat pipes operating under Stirling engine conditions, and (4) Design and fabricate a coated full-scale, partial segment of the current Stirling engine heat pipe for the Stirling Space Power Convertor program. The work effort successfully demonstrated a two-step nickel aluminide coating process for groove wick structures and interior wall surfaces in contact with liquid metals; demonstrated a one-step nickel aluminide coating process for nickel screen wick structures; and developed and demonstrated a two-step aluminum-to-nickel aluminide coating process for nickel screen wick structures. In addition, the full-scale, partial segment was fabricated and the interior surfaces and wick structures were coated. The heat pipe was charged with sodium, processed, and scheduled to be life tested for up to ten years as a Phase 3 effort.

  20. Optimization of Heat Exchangers for Intercooled Recuperated Aero Engines

    Directory of Open Access Journals (Sweden)

    Dimitrios Misirlis

    2017-03-01

    Full Text Available In the framework of the European research project LEMCOTEC, a section was devoted to the further optimization of the recuperation system of the Intercooled Recuperated Aero engine (IRA engine concept, of MTU Aero Engines AG. This concept is based on an advanced thermodynamic cycle combining both intercooling and recuperation. The present work is focused only on the recuperation process. This is carried out through a system of heat exchangers mounted inside the hot-gas exhaust nozzle, providing fuel economy and reduced pollutant emissions. The optimization of the recuperation system was performed using computational fluid dynamics (CFD computations, experimental measurements and thermodynamic cycle analysis for a wide range of engine operating conditions. A customized numerical tool was developed based on an advanced porosity model approach. The heat exchangers were modeled as porous media of predefined heat transfer and pressure loss behaviour and could also incorporate major and critical heat exchanger design decisions in the CFD computations. The optimization resulted in two completely new innovative heat exchanger concepts, named as CORN (COnical Recuperative Nozzle and STARTREC (STraight AnnulaR Thermal RECuperator, which provided significant benefits in terms of fuel consumption, pollutants emission and weight reduction compared to more conventional heat exchanger designs, thus proving that further optimization potential for this technology exists.

  1. Development of improved processing and evaluation methods for high reliability structural ceramics for advanced heat engine applications Phase II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pujari, V.J.; Tracey, D.M.; Foley, M.R. [and others

    1996-02-01

    The research program had as goals the development and demonstration of significant improvements in processing methods, process controls, and nondestructive evaluation (NDE) which can be commercially implemented to produce high reliability silicon nitride components for advanced heat engine applications at temperatures to 1370{degrees}C. In Phase I of the program a process was developed that resulted in a silicon nitride - 4 w% yttria HIP`ed material (NCX 5102) that displayed unprecedented strength and reliability. An average tensile strength of 1 GPa and a strength distribution following a 3-parameter Weibull distribution were demonstrated by testing several hundred buttonhead tensile specimens. The Phase II program focused on the development of methodology for colloidal consolidation producing green microstructure which minimizes downstream process problems such as drying, shrinkage, cracking, and part distortion during densification. Furthermore, the program focused on the extension of the process to gas pressure sinterable (GPS) compositions. Excellent results were obtained for the HIP composition processed for minimal density gradients, both with respect to room-temperature strength and high-temperature creep resistance. Complex component fabricability of this material was demonstrated by producing engine-vane prototypes. Strength data for the GPS material (NCX-5400) suggest that it ranks very high relative to other silicon nitride materials in terms of tensile/flexure strength ratio, a measure of volume quality. This high quality was derived from the closed-loop colloidal process employed in the program.

  2. Molecular engineering problems in heat and mass transfer

    International Nuclear Information System (INIS)

    Kotake, S.

    1991-01-01

    As for developing, manufacturing and applying new materials of advanced functions such as high-performance devices and high-temperature materials, fundamental understanding of the phenomena from the standpoint of molecular and atomic levels has been required. In these problems, the processes of heat and mass transfer play an important role, being one of the rate-controlling factors. But the energy levels associated with heat and mass transfer are of the orders much less than those of chemical reaction, and it is not easy to understand the thermal problems on the molecular and atomic basis. This paper views the processes of heat and mass transfer from the dynamical motions of atom and molecule for thermal engineering problems. Especially, problems are considered of heat conduction in fine-ceramics, sintered materials of high heat conductivity or high heat-insulation, phase change of condensation in vapor deposition processes such as CVD and PVD, and radiation in laser processing

  3. Heat transfer applications for the practicing engineer

    CERN Document Server

    Theodore, Louis

    2011-01-01

    This book serves as a training tool for individuals in industry and academia involved with heat transfer applications. Although the literature is inundated with texts emphasizing theory and theoretical derivations, the goal of this book is to present the subject of heat transfer from a strictly pragmatic point of view. The book is divided into four Parts: Introduction, Principles, Equipment Design Procedures and Applications, and ABET-related Topics. The first Part provides a series of chapters concerned with introductory topics that are required when solving most engineering problems, inclu

  4. Experimental Study of the Gas Engine Driven Heat Pump with Engine Heat Recovery

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2015-01-01

    Full Text Available Gas engine driven heat pumps (GEHPs represent one of practical solutions to effectively utilize fossil fuel energy and reduce environmental pollution. In this paper, the performance characteristics of the GEHP were investigated experimentally with engine heat recovery. A GEHP test facility was set up for this purpose. The effects of several important factors including engine speed, ambient temperature, condenser water flow rate, and condenser water inlet temperature on the system performance were studied over a wide range of operating conditions. The results showed that the engine waste heat accounted for about 40–50% of the total heat capacity over the studied operating conditions. It also showed that engine speed and ambient temperature had significant effects on the GEHP performance. The coefficient of performance (COP and the primary energy ratio (PER decreased by 14% and 12%, respectively, as engine speed increased from 1400 rpm to 2000 rpm. On the other hand, the COP and PER of the system increased by 22% and 16%, respectively, with the ambient temperature increasing from 3 to 12°C. Furthermore, it was demonstrated that the condenser water flow rate and condenser water inlet temperature had little influence on the COP of the heat pump and the PER of the GEHP system.

  5. Further developments in performance prediction techniques of adiabatic diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Rasihhan, Y

    1990-01-01

    The engine cycle simulation program 'SPICE', developed at Bath University, has been used extensively for insulated diesel engine research. The present study introduces more comprehensive engine heat transfer models thus enabling us to study the insulated engine heat transfer and performance characteristics in more detail. The new version of 'SPICE' separates the gas to wall heat transfer into two parts, convective and radiative. For this purpose, a detailed radiative heat transfer model which considers both the flame (gas and soot) and wall to wall radiative heat transfer is written. The previous engine resistance model is refined and replaced by a more detailed resistance model which considers piston-liner conduction heat transfer and 2-D heat flow in the liner. The wall surface temperature swing is also included in the engine heat transfer calculations which is quite significant in low conductivity ceramic insulated engines. A 1-D finite difference model is written for the transient heat transfer region of the wall and linked to the engine resistance model. This new version of 'SPICE' is used to predict the insulated engine heat transfer and performance for the experimental Petter PH1W engine for various insulation levels and schemes. An answer to the controversy of increase in engine heat loss with insulation is looked for. The effect of wall deposits on engine heat transfer and its significance for the insulated engine is highlighted. (Author).

  6. Development of monitoring system using acoustic emission for detection of helium gas leakage for primary cooling system and flow-induced vibration for heat transfer tube of heat exchangers for the High Temperature Engineering Test Reactor (HTTR)

    International Nuclear Information System (INIS)

    Tachibana, Yukio; Kunitomi, Kazuhiko; Furusawa, Takayuki; Shinozaki, Masayuki; Satoh, Yoshiyuki; Yanagibashi, Minoru

    1998-10-01

    The High Temperature Engineering Test Reactor (HTTR) uses helium gas for its primary coolant, whose leakage inside reactor containment vessel is considered in design of the HTTR. It is necessary to detect leakage of helium gas at an early stage so that total amount of the leakage should be as small as possible. On the other hand, heat transfer tubes of heat exchangers of the HTTR are designed not to vibrate at normal operation, but the flow-induced vibration is to be monitored to provide against an emergency. Thus monitoring system of acoustic emission for detection of primary coolant leakage and vibration of heat transfer tubes was developed and applied to the HTTR. Before the application to the HTTR, leakage detection test was performed using 1/4 scaled model of outer tube of primary concentric hot gas duct. Result of the test covers detectable minimum leakage rate and effect of difference in gas, pressure, shape of leakage path and distance from the leaking point. Detectable minimum leakage rate was about 5 Ncc/sec. The monitoring system is promising in leakage detection, though countermeasure to noise is to be needed after the HTTR starts operating. (author)

  7. Two-phase plate-fin heat exchanger modeling for waste heat recovery systems in diesel engines

    NARCIS (Netherlands)

    Feru, E.; Jager, de A.G.; Willems, F.P.T.; Steinbuch, M.

    2014-01-01

    This paper presents the modeling and model validation for a modular two-phase heat exchanger that recovers energy in heavy-duty diesel engines. The model is developed for temperature and vapor quality prediction and for control design of the waste heat recovery system. In the studied waste heat

  8. Superconductor Particles As The Working Media Of A Heat Engine

    Science.gov (United States)

    Keefe, Peter D.

    2011-12-01

    A heat engine is presented in which the working media comprises a multiplicity of mutually isolated particles of Type I superconductor which are selectively processed through H-T phase space so as to convert a heat influx from a high temperature heat reservoir into a useful work output, wherein no heat is rejected to a low temperature heat reservoir.

  9. Sorption heat engines: simple inanimate negative entropy generators

    OpenAIRE

    Muller, Anthonie W. J.; Schulze-Makuch, Dirk

    2005-01-01

    The name 'sorption heat engines' is proposed for simple negative entropy generators that are driven by thermal cycling and work on alternating adsorption and desorption. These generators are in general not explicitly recognized as heat engines. Their mechanism is applicable to the fields of engineering, physics, chemistry, geology, and biology, in particular the origin of life. Four kinds of sorption heat engines are distinguished depending on the occurrence of changes in the adsorbent or ads...

  10. Engineering and economic aspects of centalized heating from nuclear boilers

    International Nuclear Information System (INIS)

    Emel'yanov, I.Ya.; Baturov, B.B.; Korytnikov, V.P.; Koryakin, Yu.I.; Chernyaev, V.A.; Kovylyanskij, Ya.A.; Galaktionov, I.V.

    1979-01-01

    Some engineering and economic aspects for deployment of centralized nuclear boilers (NB) in the USSR are considered. Engineering, maintenance and economic features of NB as compared to organic-fuelled boilers and nuclear thermal power plants are discussed. Among major factors governing economic efficiency of NB underlined are oraganic fuel costs, reactor unit power, location relative to heat-consuming centres and capacity factor. It is concluded that NB can be economical for heating large consumers (more than 1500 G kal/hr). At the periphery NB can be competitive already at reactor unit power of several MWth. The development of HTGR type reactor-based nuclear-chemical boilers and lines for heat transport in a chemically bound state (e.g., CH 4 → H 2 +CO 2 +CO → CH 4 ) opens the way for a substantial breakthrow in the centralized NB efficiency

  11. Quantum heat engine with coupled superconducting resonators

    DEFF Research Database (Denmark)

    Hardal, Ali Ümit Cemal; Aslan, Nur; Wilson, C. M.

    2017-01-01

    the differences between the quantum and classical descriptions of our system by solving the quantum master equation and classical Langevin equations. Specifically, we calculate the mean number of excitations, second-order coherence, as well as the entropy, temperature, power, and mean energy to reveal......We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one...... the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures....

  12. Quantum optomechanical piston engines powered by heat

    Science.gov (United States)

    Mari, A.; Farace, A.; Giovannetti, V.

    2015-09-01

    We study two different models of optomechanical systems where a temperature gradient between two radiation baths is exploited for inducing self-sustained coherent oscillations of a mechanical resonator. From a thermodynamic perspective, such systems represent quantum instances of self-contained thermal machines converting heat into a periodic mechanical motion and thus they can be interpreted as nano-scale analogues of macroscopic piston engines. Our models are potentially suitable for testing fundamental aspects of quantum thermodynamics in the laboratory and for applications in energy efficient nanotechnology.

  13. Quantum optomechanical piston engines powered by heat

    International Nuclear Information System (INIS)

    Mari, A; Farace, A; Giovannetti, V

    2015-01-01

    We study two different models of optomechanical systems where a temperature gradient between two radiation baths is exploited for inducing self-sustained coherent oscillations of a mechanical resonator. From a thermodynamic perspective, such systems represent quantum instances of self-contained thermal machines converting heat into a periodic mechanical motion and thus they can be interpreted as nano-scale analogues of macroscopic piston engines. Our models are potentially suitable for testing fundamental aspects of quantum thermodynamics in the laboratory and for applications in energy efficient nanotechnology. (paper)

  14. Optimization of powered Stirling heat engine with finite speed thermodynamics

    International Nuclear Information System (INIS)

    Ahmadi, Mohammad H.; Ahmadi, Mohammad Ali; Pourfayaz, Fathollah; Bidi, Mokhtar; Hosseinzade, Hadi; Feidt, Michel

    2016-01-01

    Highlights: • Based on finite speed method and direct method, the optimal performance is investigated. • The effects of major parameters on the optimal performance are investigated. • The accuracy of the results was compared with previous works. - Abstract: Popular thermodynamic analyses including finite time thermodynamic analysis was lately developed based upon external irreversibilities while internal irreversibilities such as friction, pressure drop and entropy generation were not considered. The aforementioned disadvantage reduces the reliability of the finite time thermodynamic analysis in the design of an accurate Stirling engine model. Consequently, the finite time thermodynamic analysis could not sufficiently satisfy researchers for implementing in design and optimization issues. In this study, finite speed thermodynamic analysis was employed instead of finite time thermodynamic analysis for studying Stirling heat engine. The finite speed thermodynamic analysis approach is based on the first law of thermodynamics for a closed system with finite speed and the direct method. The effects of heat source temperature, regenerating effectiveness, volumetric ratio, piston stroke as well as rotational speed are included in the analysis. Moreover, maximum output power in optimal rotational speed was calculated while pressure losses in the Stirling engine were systematically considered. The result reveals the accuracy and the reliability of the finite speed thermodynamic method in thermodynamic analysis of Stirling heat engine. The outcomes can help researchers in the design of an appropriate and efficient Stirling engine.

  15. A heating system for piglets in farrowing house using waste heat from biogas engine

    Directory of Open Access Journals (Sweden)

    Payungsak Junyusen

    2008-12-01

    Full Text Available The aim of this study is to design and test a heating system for piglets in farrowing house by utilising the waste heat from a biogas engine as a heat source. The study was separated into three parts: the study on the biogas combined heat and power plant, the investigation on the properties of the heat panel, and the installation and testing of the heating system. From the experiment, the condition producing 60 kW of electrical power was a proper one, in which electrical efficiency and specific fuel consumption were 14% and 1.22 m3/kWh respectively. Generating both electricity and heat increased the overall efficiency to 37.7% and decreased the specific fuel consumption to 0.45 m3/kWh. The heat panel, which was made of a plastic material, had a thermal conductivity of 0.58 W/mC and the maximum compressive force and operating pressure of 8.1 kN and 0.35 bar respectively. The surface temperature of the panel was dependent on the inlet water temperature. When hot water of 44C was supplied into the farrowing house with room temperature of 26C, the average surface temperature was 33C. The developed heating system could provide heat for 4.3 farrowing houses. The payback period of this project was 2.5 years.

  16. Utilisation of diesel engine waste heat by Organic Rankine Cycle

    International Nuclear Information System (INIS)

    Kölsch, Benedikt; Radulovic, Jovana

    2015-01-01

    In this paper, three different organic liquids were investigated as potential working fluids in an Organic Rankine Cycle. Performance of Methanol, Toluene and Solkatherm SES36 was modelled in an ORC powered by a diesel engine waste heat. The ORC model consists of a preheater, evaporator, superheater, turbine, pump and two condensers. With variable maximum cycle temperatures and high cycle pressures, the thermal efficiency, net power output and overall heat transfer area have been evaluated. Methanol was found to have the best thermal performance, but also required the largest heat transfer area. While Toluene achieved lower thermal efficiency, it showed great work potential at high pressures and relatively low temperatures. Our model identified the risks associated with employing these fluids in an ORC: methanol condensing during the expansion and toluene not sufficiently superheated at the turbine inlet, which can compromise the cycle operation. The best compromise between the size of heat exchanger and thermodynamic performance was found for Methanol ORC at intermediate temperatures and high pressures. Flammability and toxicity, however, remain the obstacles for safe implementation of both fluids in ORC systems. - Highlights: • ORC powered by diesel-engine waste heat was developed. • Methanol, Toluene and Solkatherm were considered as working fluids. • Methanol was selected due to the best overall thermal performance. • Optimal cycle operating parameters and heat exchanger area were evaluated

  17. Boiling heat transfer modern developments and advances

    CERN Document Server

    Lahey, Jr, RT

    2013-01-01

    This volume covers the modern developments in boiling heat transfer and two-phase flow, and is intended to provide industrial, government and academic researchers with state-of-the-art research findings in the area of multiphase flow and heat transfer technology. Special attention is given to technology transfer, indicating how recent significant results may be used for practical applications. The chapters give detailed technical material that will be useful to engineers and scientists who work in the field of multiphase flow and heat transfer. The authors of all chapters are members of the

  18. Heat transfers through diesel-engine cylinder liners

    Energy Technology Data Exchange (ETDEWEB)

    Green, R T; Jambunathan, K; Probert, S D

    1983-01-01

    A computer package has been developed, using a finite-element technique, to predict the steady-state rate of heat transfer radially through the cylinder liner, or other axisymmetric components, of a medium-speed diesel engine. Comparisons between experimentally measured and computer predicted results have been made: better corroboration occurs for engine loads above 1034 k N m/sup -2/ BMEP. The predictive computer package DIESHT needs only a simple 'user input' and produces a complete graphical output of generated mesh and computed isotherms. Computational storage requirements are modest so that the program can be used with a CAD system, if required, in order to facilitate an interactive design procedure.

  19. Improving Engine Oil Warm Up through Waste Heat Recovery

    Directory of Open Access Journals (Sweden)

    Davide Di Battista

    2017-12-01

    Full Text Available In the transportation sector, engine oil thermal management has not yet received the attention it deserves in the path towards carbon dioxide and pollutants reduction. During the homologation cycle (which represents a typical daily trip, oil temperature reaches its thermal steady value, which insures best performances in terms of viscosity, only in the final part of the trip, when most part of the harmful emissions have been already emitted; therefore, a warm up acceleration would surely represent a strong beneficial action. In this paper, a faster warming up of the lubricant oil was done using the heat owned by the exhaust gases, which was almost immediately ready after the engine ignition, in the early part of a driving cycle. An experimental activity has been developed in a turbocharged engine (F1C 3L IVECO, modifying the oil circuit in order to heat up the oil during the cold phase of a homologation cycle by the exhaust gases. A significant reduction of fuel consumption and pollutant emissions savings has been experimentally demonstrated. Also, the interaction between the modified oil circuit, engine, coolant circuit, and exhaust line has been investigated in order to have a system view of the new heating oil technology.

  20. Holographic heat engine within the framework of massive gravity

    Science.gov (United States)

    Mo, Jie-Xiong; Li, Gu-Qiang

    2018-05-01

    Heat engine models are constructed within the framework of massive gravity in this paper. For the four-dimensional charged black holes in massive gravity, it is shown that the existence of graviton mass improves the heat engine efficiency significantly. The situation is more complicated for the five-dimensional neutral black holes since the constant which corresponds to the third massive potential also contributes to the efficiency. It is also shown that the existence of graviton mass can improve the heat engine efficiency. Moreover, we probe how the massive gravity influences the behavior of the heat engine efficiency approaching the Carnot efficiency.

  1. Developing systems engineers

    CSIR Research Space (South Africa)

    Goncalves, D

    2008-07-01

    Full Text Available will have rendered him incapable of dealing with the majority of problems that will face him.” (Quoted in [12]). UP has applied the SPICES model, proposed by Harden et al. [12], for developing their medical curriculum. Some aspects of the model... are useful to developing systems engineers and will be considered in SE terms at a relevant level of detail. The SPICES model is contrasted against traditional medical curriculum approaches in TABLE 1. These are two extremes on a continuum. Traditional...

  2. Engineering sustainable development

    International Nuclear Information System (INIS)

    Prendergast, J.

    1993-01-01

    This article discusses sustainable development, a policy which attempts to balance environmental preservation and economic growth, and promises a way to provide a decent life for Earth's human inhabitants without destroying the global ecosystem. Sustainable development is an effort to use technology to help clean up the mess it helped make, and engineers will be central players in its success or failure. Key aspects include more efficient energy use through conservation measures and switching to renewable sources, waste minimization, much greater recycling and reuse of materials, more comprehensive economic/environmental assessments employing life-cycle analyses, and better management of resources

  3. Quantum heat engine with coupled superconducting resonators

    Science.gov (United States)

    Hardal, Ali Ü. C.; Aslan, Nur; Wilson, C. M.; Müstecaplıoǧlu, Özgür E.

    2017-12-01

    We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one due to the coupling. A limit cycle, indicating finite power output, emerges in the thermodynamical phase space. The system implements an all-electrical analog of a photonic piston. Instead of mechanical motion, the power output is obtained as a coherent electrical charging in our case. We explore the differences between the quantum and classical descriptions of our system by solving the quantum master equation and classical Langevin equations. Specifically, we calculate the mean number of excitations, second-order coherence, as well as the entropy, temperature, power, and mean energy to reveal the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures.

  4. Black holes in massive gravity as heat engines

    Science.gov (United States)

    Hendi, S. H.; Eslam Panah, B.; Panahiyan, S.; Liu, H.; Meng, X.-H.

    2018-06-01

    The paper at hand studies the heat engine provided by black holes in the presence of massive gravity. The main motivation is to investigate the effects of massive gravity on different properties of the heat engine. It will be shown that massive gravity parameters modify the efficiency of engine on a significant level. Furthermore, it will be pointed out that it is possible to have a heat engine for non-spherical black holes in massive gravity, and therefore, we will study the effects of horizon topology on the properties of heat engine. Surprisingly, it will be shown that the highest efficiency for the heat engine belongs to black holes with the hyperbolic horizon, while the lowest one belongs to the spherical black holes.

  5. Development of improved processing and evaluation methods for high reliability structural ceramics for advanced heat engine applications, Phase 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pujari, V.K.; Tracey, D.M.; Foley, M.R.; Paille, N.I.; Pelletier, P.J.; Sales, L.C.; Wilkens, C.A.; Yeckley, R.L. [Norton Co., Northboro, MA (United States)

    1993-08-01

    The program goals were to develop and demonstrate significant improvements in processing methods, process controls and non-destructive evaluation (NDE) which can be commercially implemented to produce high reliability silicon nitride components for advanced heat engine applications at temperatures to 1,370{degrees}C. The program focused on a Si{sub 3}N{sub 4}-4% Y{sub 2}O{sub 3} high temperature ceramic composition and hot-isostatic-pressing as the method of densification. Stage I had as major objectives: (1) comparing injection molding and colloidal consolidation process routes, and selecting one route for subsequent optimization, (2) comparing the performance of water milled and alcohol milled powder and selecting one on the basis of performance data, and (3) adapting several NDE methods to the needs of ceramic processing. The NDE methods considered were microfocus X-ray radiography, computed tomography, ultrasonics, NMR imaging, NMR spectroscopy, fluorescent liquid dye penetrant and X-ray diffraction residual stress analysis. The colloidal consolidation process route was selected and approved as the forming technique for the remainder of the program. The material produced by the final Stage II optimized process has been given the designation NCX 5102 silicon nitride. According to plan, a large number of specimens were produced and tested during Stage III to establish a statistically robust room temperature tensile strength database for this material. Highlights of the Stage III process demonstration and resultant database are included in the main text of the report, along with a synopsis of the NCX-5102 aqueous based colloidal process. The R and D accomplishments for Stage I are discussed in Appendices 1--4, while the tensile strength-fractography database for the Stage III NCX-5102 process demonstration is provided in Appendix 5. 4 refs., 108 figs., 23 tabs.

  6. Analysis on the heating performance of a gas engine driven air to water heat pump based on a steady-state model

    International Nuclear Information System (INIS)

    Zhang, R.R.; Lu, X.S.; Li, S.Z.; Lin, W.S.; Gu, A.Z.

    2005-01-01

    In this study, the heating performance of a gas engine driven air to water heat pump was analyzed using a steady state model. The thermodynamic model of a natural gas engine is identified by the experimental data and the compressor model is created by several empirical equations. The heat exchanger models are developed by the theory of heat balance. The system model is validated by comparing the experimental and simulation data, which shows good agreement. To understand the heating characteristic in detail, the performance of the system is analyzed in a wide range of operating conditions, and especially the effect of engine waste heat on the heating performance is discussed. The results show that engine waste heat can provide about 1/3 of the total heating capacity in this gas engine driven air to water heat pump. The performance of the engine, heat pump and integral system are analyzed under variations of engine speed and ambient temperature. It shows that engine speed has remarkable effects on both the engine and heat pump, but ambient temperature has little influence on the engine's performance. The system and component performances in variable speed operating conditions is also discussed at the end of the paper

  7. Environmental Engineering and Sustainable Development

    OpenAIRE

    Said Salah Eldin Elnashaie

    2018-01-01

    Chemical Engineering is a very rich discipline and it is best classified using System Theory (ST) and utilized using the Integrated System Approach (ISA). Environmental Engineering (EE) is a subsystem of Chemical Engineering and also a subsystem of Sustainable Development (SD). In this paper both EE and SD are discussed from a Chemical Engineering point of view utilizing ST and ISA.

  8. Heat transfer correlation development and assessment: a summary and assessment of return to nucleate boiling phenomena during blowdown tests conducted at the Idaho National Engineering Laboratory (INEL)

    International Nuclear Information System (INIS)

    Eaton, A.M.; Tolman, E.L.

    1979-04-01

    The data are presented which were obtained in Loss-of-Coolant Experiments (LOCE) at Idaho National Engineering Laboratory (INEL) which demonstrate the presence of cladding rewetting after the critical heat flux has been exceeded as a viable cooling mechanism during the blowdown phase of a LOCE. A brief review of the mechanisms associated with the boiling crisis and rewetting is also provided. The relevance of INEL LOCE rewetting data to nuclear reactor licensing Evaluation Model Requirements is considered, and the conclusion is made that the elimination of rewetting and return to nucleate boiling (RNB) in Evaluation Models represents a definite conservatism

  9. A quantum Szilard engine without heat from a thermal reservoir

    Science.gov (United States)

    Hamed Mohammady, M.; Anders, Janet

    2017-11-01

    We study a quantum Szilard engine that is not powered by heat drawn from a thermal reservoir, but rather by projective measurements. The engine is constituted of a system { S }, a weight { W }, and a Maxwell demon { D }, and extracts work via measurement-assisted feedback control. By imposing natural constraints on the measurement and feedback processes, such as energy conservation and leaving the memory of the demon intact, we show that while the engine can function without heat from a thermal reservoir, it must give up at least one of the following features that are satisfied by a standard Szilard engine: (i) repeatability of measurements; (ii) invariant weight entropy; or (iii) positive work extraction for all measurement outcomes. This result is shown to be a consequence of the Wigner-Araki-Yanase theorem, which imposes restrictions on the observables that can be measured under additive conservation laws. This observation is a first-step towards developing ‘second-law-like’ relations for measurement-assisted feedback control beyond thermality.

  10. Study of heat insulated turbo compound engine. Shanetsugata tabo konpaundo engine to tomoni ayumu

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, K [Isuzu Motors Ltd., Tokyo (Japan). Ceramics Research Lab.

    1994-02-01

    For a main purpose of development of the heat insulated turbo compound engine using the ceramics, the Isuzu Ceramics Inst. Co., Ltd. was established by the Isuzu Motors Ltd. in 1988. The main study subjects take up various topics such as a development of the new engine system for actualizing a low fuel consumption and low emission, an improvement of deteriorated combustion caused by the insulation, a development of energy recovery facility for utilizing effectively the exhaust energy from the engines, a development of power electronics technology for controlling the recovery facility, a study and development of ceramics as the insulation material and so forth. The outstanding characteristics of this institute are that a development of the heat insulated turbo compound engine is set as the main study subject, but at the same time that a commercialization of the various derivation technology derived from this study. Even just the main study subjects currently under way are counted up to a number close to 10 items, and consequently the efforts are being continued in each field assigned for solving the subjects. 6 figs.

  11. Hot Hydrogen Heat Source Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop a  hot hydrogen heat source that would produce  a high temperature hydrogen flow which would be comparable to that produced...

  12. Engineering design aspects of the heat-pipe power system

    International Nuclear Information System (INIS)

    Capell, B.M.; Houts, M.G.; Poston, D.I.; Berte, M.

    1997-10-01

    The Heat-pipe Power System (HPS) is a near-term, low-cost space power system designed at Los Alamos that can provide up to 1,000 kWt for many space nuclear applications. The design of the reactor is simple, modular, and adaptable. The basic design allows for the use of a variety of power conversion systems and reactor materials (including the fuel, clad, and heat pipes). This paper describes a project that was undertaken to develop a database supporting many engineering aspects of the HPS design. The specific tasks discussed in this paper are: the development of an HPS materials database, the creation of finite element models that will allow a wide variety of investigations, and the verification of past calculations

  13. Engineering design aspects of the heat-pipe power system

    Science.gov (United States)

    Capell, B. M.; Houts, M. G.; Poston, D. I.; Berte, M.

    1997-01-01

    The Heat-pipe Power System (HPS) is a near-term, low-cost space power system designed at Los Alamos that can provide up to 1,000 kWt for many space nuclear applications. The design of the reactor is simple, modular, and adaptable. The basic design allows for the use of a variety of power conversion systems and reactor materials (including the fuel, clad, and heat pipes). This paper describes a project that was undertaken to develop a database supporting many engineering aspects of the HPS design. The specific tasks discussed in this paper are: the development of an HPS materials database, the creation of finite element models that will allow a wide variety of investigations, and the verification of past calculations.

  14. A quantum heat engine based on Tavis-Cummings model

    Science.gov (United States)

    Sun, Kai-Wei; Li, Ran; Zhang, Guo-Feng

    2017-09-01

    This paper will investigate a four-stroke quantum heat engine based on the Tavis-Cummings model. The cycle of the heat engine is similar to the Otto cycle in classical thermodynamics. The relationship between output power as well as cycle efficiency and external physical system parameters are given. Under this condition, the entanglement behavior of the system will be studied. The system can show considerable entanglement by strictly controlling relevant parameters. Unlike common two-level quantum heat engines, efficiency is a function of temperature, showing interesting and unexpected phenomena. Several ways to adjust engine properties by external parameters are proposed, with which the output power and efficiency can be optimized. The heat engine model exhibits high efficiency and output power with the participation of a small number of photons, and decay rapidly as the number of photons increases in entangled area but shows interesting behaviors in non-entangled area of photon numbers.

  15. On the question of heat engine cycles optimization

    Directory of Open Access Journals (Sweden)

    Костянтин Ігорович Ткаченко

    2015-10-01

    Full Text Available It is known that the efficiency of heat engines nowadays isn’t more than 50-60% for prototypes and maximum possible efficiency of a heat engine is considered Carnot cycle efficiency Thus, at least 40% of the disposable amount of heat is lost in the surrounding medium, unless the waste gases heat is utilized somehow. General idea of heat engines cycles is the transfer of energy from the heater (both external and internal to a working fluid, obtaining mechanical work from expanding of the working fluid, and returning the working fluid to the initial state by compression and excess heat discharge into a cooler. In this paper the combination of a heat engine operating according to the standard Edwards cycle and consisting of isochor, adiabat and isotherm, and the heat pump, using the reverse Carnot cycle is investigated. The heat pump partially picks out the heat of the working fluid at its isothermal compression, and returns it to the equivalent working fluid or regenerator cap, at the beginning of isochoric heating. The efficiency coefficient of the heat pump, and thus the work to putting it into action is calculated by proper equations at the constant temperature of the low-potential heat source (working fluid and variable temperature of the heated equivalent of the working fluid or the regenerator cap. Taking as an example selected quantitative parameters of the Edwards cycle it has been proved that the use of the heat pump increases the effective efficiency of combined cycle as compared to the basic one. In addition, it has been shown that the dependence of the efficiency on the degree of heat return is not monotonic and has a maximum

  16. On the importance of specific heats as regards efficiency increases for highly dilute IC engines

    International Nuclear Information System (INIS)

    Caton, Jerald A.

    2014-01-01

    Highlights: • Importance of specific heats towards increasing engine efficiency was quantified. • Decreases of specific heats contribute 3.5–6.3% (abs) to the efficiency. • Dilute engines benefit from decreases of specific heats due to lower temperatures. - Abstract: Engineering and scientific efforts continue with the development of advanced, IC engines using highly dilute mixtures, and relatively high compression ratios. Such engines are known to provide opportunities for low emissions as well as high efficiencies. The main features of these engines include higher compression ratios, lean operation, use of EGR, and shorter burn durations. First, this study reviews the quantitative contributions of each of these features as determined by an engine cycle simulation. Second, this study provides the quantitative contributions to the increased efficiency in terms of fundamental thermodynamic considerations. An automotive engine operated at 2000 rpm was selected for this study. For the conditions examined, the net indicated thermal efficiency increased from 37.0% (conventional engine) to 53.9% (high efficiency engine) – for an incremental increase of 16.9% (absolute). The contribution of increases of the ratio of specific heats towards the final thermal efficiency is quantified. This aspect has been well known, but has not been quantified for actual engines. For the various conditions examined, 21–35% of the total efficiency improvement was estimated to be due to the increase of the ratio of specific heats

  17. Heat pipes to reduce engine exhaust emissions

    Science.gov (United States)

    Schultz, D. F. (Inventor)

    1984-01-01

    A fuel combustor is presented that consists of an elongated casing with an air inlet conduit portion at one end, and having an opposite exit end. An elongated heat pipe is mounted longitudinally in the casing and is offset from and extends alongside the combustion space. The heat pipe is in heat transmitting relationship with the air intake conduit for heating incoming air. A guide conduit structure is provided for conveying the heated air from the intake conduit into the combustion space. A fuel discharge nozzle is provided to inject fuel into the combustion space. A fuel conduit from a fuel supply source has a portion engaged in heat transfer relationship of the heat pipe for preheating the fuel. The downstream end of the heat pipe is in heat transfer relationship with the casing and is located adjacent to the downstream end of the combustion space. The offset position of the heat pipe relative to the combustion space minimizes the quenching effect of the heat pipe on the gaseous products of combustion, as well as reducing coking of the fuel on the heat pipe, thereby improving the efficiency of the combustor.

  18. Results of studying of turbulent heat transfer deterioration and their application for development of engineering methods of calculation of heat transfer and pressure drop in supercritical-pressure coolant flow

    International Nuclear Information System (INIS)

    Vladimir A Kurganov; Yuri A Zeigarnik

    2005-01-01

    Full text of publication follows: Using of the supercritical-pressure (SCP) water as a working medium is an apparent way to increase specific capacity and economic efficiency of nuclear power installations. Nevertheless, to provide safe operation of SCP nuclear power units, it is necessary to considerably improve reliability and accuracy of calculations of pressure drop and heat transfer in the SCP working media and coolants flows and the methods of forecasting such a dangerous phenomenon as deterioration of the turbulent heat transfer at a certain level of heat flux density. A value of the latter changes within a very large range depending on the specific conditions of the process under consideration. In the paper, the main results of the experimental study of heat transfer, pressure drop, and velocity and temperature fields in both upward and downward flows of the SCP CO 2 in tubes are considered. This study was conducted at OIVT RAN under conditions of heat input and embraced the regimes of normal and deteriorated heat transfer as well. On the basis of this data, the concept regarding to physical mechanism of incipience of the regimes of deteriorated heat transfer was developed. Classification of different modes of heat transfer deterioration in vertical channels is proposed. A degree of a danger of certain regimes is assessed. It is shown that the above phenomenon is caused by transformation of the structure of nonisothermal flow of SCP fluid due to changes in proportions between the forces acting upon a flow, specifically, because of an increase in the inertia forces due to thermal acceleration of a flow and/or in Archimedes' (buoyancy) forces up to the level comparable or higher than that of friction forces. The efficiency of the most thorough correlations for calculating normal and deteriorated heat transfer in flows of SCP water and CO 2 is analyzed. Reliability of existed recommendations to determine boundaries of normal heat transfer regimes is considered

  19. The heat engine cycle, the heat removal cycle, and ergonomics of the control room displays

    International Nuclear Information System (INIS)

    Beltracchi, L.

    1986-01-01

    This paper discusses and illustrates the ergonomics of an integrated display, which will allow operators to monitor the heat engine cycle during normal operation of the plant, and the heat removal cycle during emergency operation of the plant. A computer-based iconic display is discussed as an overview to monitor these cycles. Specific emphasis is placed upon the process variables and process functions within each cycle, and the action of control systems and engineered safeguard systems within each cycle. This paper contains examples of display formats for the heat engine cycle and the heat removal cycle in a pressurized water reactor

  20. Heat Transfer Analysis of a Diesel Engine Head

    Directory of Open Access Journals (Sweden)

    M. Diviš

    2003-01-01

    Full Text Available This paper documents the research carried out at the Josef Božek Research Center of Engine and Automotive Engineering dealing with extended numerical stress/deformation analyses of engines parts loaded by heat and mechanical forces. It contains a detailed description of a C/28 series diesel engine head FE model and a discussion of heat transfer analysis tunning and results. The head model consisting of several parts allows a description of contact interaction in both thermal and mechanical analysis.

  1. Development of engineered barrier

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  2. Development of engineered barrier

    International Nuclear Information System (INIS)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and 316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  3. Optimization of the dynamic and thermal performance of a resonant micro heat engine

    International Nuclear Information System (INIS)

    Bardaweel, H K; Richards, R F; Richards, C D; Anderson, M J

    2008-01-01

    The dynamic behavior of a flexing membrane micro heat engine is presented. The micro heat engine consists of a cavity filled with a saturated, two-phase working fluid bounded on the top by a flexible expander membrane and on the bottom by a stiff evaporator membrane. A lumped parameter model is developed to simulate the dynamic behavior of the micro heat engine. First, the model is validated against experimental data. Then, the model is used to investigate the effect of the duration of the heat addition process, the mass of the expander membrane and the thermal storage or thermal inertia associated with the engine cavity on the dynamic behavior of the micro engine. The results show the optimal duration for the heat addition process to be less than 10% of the engine cycle period. Increasing the mass of the flexible expander membrane is shown to reduce the resonant frequency of the engine to 130 Hz. Operating the engine at resonance leads to increased power output. The thermal storage or thermal inertia associated with the engine cavity is shown to have a strong effect on engine performance

  4. Optimal power and efficiency of quantum Stirling heat engines

    Science.gov (United States)

    Yin, Yong; Chen, Lingen; Wu, Feng

    2017-01-01

    A quantum Stirling heat engine model is established in this paper in which imperfect regeneration and heat leakage are considered. A single particle which contained in a one-dimensional infinite potential well is studied, and the system consists of countless replicas. Each particle is confined in its own potential well, whose occupation probabilities can be expressed by the thermal equilibrium Gibbs distributions. Based on the Schrödinger equation, the expressions of power output and efficiency for the engine are obtained. Effects of imperfect regeneration and heat leakage on the optimal performance are discussed. The optimal performance region and the optimal values of important parameters of the engine cycle are obtained. The results obtained can provide some guidelines for the design of a quantum Stirling heat engine.

  5. Non-Markovian Investigation of an Autonomous Quantum Heat Engine

    Science.gov (United States)

    Goyal, Ketan

    A systematic study of a quantum heat engine is presented in this thesis. In particular, we study heat conduction through a two-two level composite system, which is then connected to a photon cavity to extract work, forming an autonomous quantum heat engine. The question as to what extent quantum effects such as quantum coherence and correlations impact thermodynamic properties of such a system is addressed. The investigated heat engine has been previously studied using the popular Born-Markovian quantum master equation under weak internal coupling approximation. However, we show that the used approach is quite limited in addressing such problems as it is incapable of correctly accounting for the quantum effects. By using a non-Markovian approach involving hierarchical equations of motion, we show that quantum coherence and correlations between system and environments play a significant role in energy transfer processes of heat conduction and work.

  6. Experimental assessment for instantaneous temperature and heat flux measurements under Diesel motored engine conditions

    International Nuclear Information System (INIS)

    Torregrosa, A.J.; Bermúdez, V.; Olmeda, P.; Fygueroa, O.

    2012-01-01

    Higlights: ► We measured in-cylinder wall heat fluxes. ► We examine the effects of different engine parameters. ► Increasing air mass flow increase heat fluxes. ► The effect of engine speed can be masked by the effect of volumetric efficiency. ► Differences among the different walls have been found. - Abstract: The main goal of this work is to validate an innovative experimental facility and to establish a methodology to evaluate the influence of some of the engine parameters on local engine heat transfer behaviour under motored steady-state conditions. Instantaneous temperature measurements have been performed in order to estimate heat fluxes on a modified Diesel single cylinder combustion chamber. This study was divided into two main parts. The first one was the design and setting on of an experimental bench to reproduce Diesel conditions and perform local-instantaneous temperature measurements along the walls of the combustion chamber by means of fast response thermocouples. The second one was the development of a procedure for temperature signal treatment and local heat flux calculation based on one-dimensional Fourier analysis. A thermodynamic diagnosis model has been employed to characterise the modified engine with the new designed chamber. As a result of the measured data coherent findings have been obtained in order to understand local behaviour of heat transfer in an internal combustion engine, and the influence of engine parameters on local instantaneous temperature and heat flux, have been analysed.

  7. Generalized irreversible heat-engine experiencing a complex heat-transfer law

    International Nuclear Information System (INIS)

    Chen Lingen; Li Jun; Sun Fengrui

    2008-01-01

    The fundamental optimal relation between optimal power-output and efficiency of a generalized irreversible Carnot heat-engine is derived based on a generalized heat-transfer law, including a generalized convective heat-transfer law and a generalized radiative heat-transfer law, q ∝ (ΔT n ) m . The generalized irreversible Carnot-engine model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat-leak, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities, besides heat resistance, are characterized by a constant parameter and a constant coefficient. The effects of heat-transfer laws and various loss terms are analyzed. The results obtained corroborate those in the literature

  8. Evaluation of heat transfer correlations for HCCI engine modeling

    NARCIS (Netherlands)

    Soyhan, H.S.; Yasar, H.; Walmsley, H.; Head, B.; Kalghatgi, G.T.; Sorusbay, C.

    2009-01-01

    Combustion in HCCI engines is a controlled auto-ignition of well-mixed fuel, air and residual gas. The thermal conditions of the combustion chamber are governed by chemical kinetics strongly coupled with heat transfer from the hot gas to the walls. The heat losses have a critical effect on HCCI

  9. Design procedures for heat-straightening repair : an engineering guide.

    Science.gov (United States)

    1992-12-01

    This report summarizes over four years of research on heat-straightening repairs and provides a prototype engineering guide for the application of heat-straightening to bridge structures. It is based on the research results detailed in a companion re...

  10. Performance analysis of diesel engine heat pump incorporated with heat recovery

    International Nuclear Information System (INIS)

    Shah, N.N.; Huang, M.J.; Hewitt, N.J.

    2016-01-01

    Highlights: • Diesel engine heat pump with heat recovery. • Water-to-water source heat pump based on R134a. • Possibility for different flow temperature for heat distribution system. • Possible retrofit application in off-gas or weak electricity network area. • Potential to diversify use of fossil fuel, primary energy and CO_2 emission savings. - Abstract: This paper presents experimental study of diesel engine heat pump (DEHP) system to find potential as retrofit technology in off-gas or weak electricity network area to replace existing gas/oil/electric heating system in domestic sector. Test set-up of diesel engine driven water-to-water heat pump system was built which included heat recovery arrangement from the engine coolant & exhaust gas. The system was designed to meet typical house heating demand in Northern Ireland. Performance of DEHP was evaluated to meet house-heating demand at different flow temperature (35, 45, 55 & 65 °C), a typical requirement of underfloor space heating, medium/high temperature radiators and domestic hot water. The performance was evaluated against four-evaporator water inlet temperature (0, 5, 10 & 15 °C) and at three different engine speed 1600, 2000 & 2400 rpm. Experiment results were analysed in terms of heating/cooling capacity, heat recovery, total heat output, primary energy ratio (PER), isentropic efficiency, etc. Test results showed that DEHP is able to meet house-heating demand with help of heat recovery with reduced system size. Heat recovery contributed in a range of 22–39% in total heat output. It is possible to achieve high flow temperature in a range of 74 °C with help of heat recovery. Overall system PER varied in a range of 0.93–1.33. Speed increment and flow temperature has significant impact on heat recovery, total heat output and PER. A case scenario with different flow temperature to match house-heating demand has been presented to show working potential with different heat distribution system

  11. Geothermal heating a handbook of engineering economics

    CERN Document Server

    Harrison, R; Smarason, O B

    2013-01-01

    To date all books on geothermics have emphasized its use for generating electricity, with applications of lower grade resources for direct heating meriting only a brief chapter. This book brings together research from a range of scientific journals and 'grey' literature to produce the first comprehensive text on geothermal heating. Economics form an important part of the book. It provides a step by step analysis of the various ways in which thermal waters can be used to provide space heating and of the advantages and disadvantages of different approaches. The final section of the book provides

  12. Design and instrumentation of an automotive heat pump system using ambient air, engine coolant and exhaust gas as a heat source

    International Nuclear Information System (INIS)

    Hosoz, M.; Direk, M.; Yigit, K.S.; Canakci, M.; Alptekin, E.; Turkcan, A.

    2009-01-01

    Because the amount of waste heat used for comfort heating of the passenger compartment in motor vehicles decreases continuously as a result of the increasing engine efficiencies originating from recent developments in internal combustion engine technology, it is estimated that heat requirement of the passenger compartment in vehicles using future generation diesel engines will not be met by the waste heat taken from the engine coolant. The automotive heat pump (AHP) system can heat the passenger compartment individually, or it can support the present heating system of the vehicle. The AHP system can also be employed in electric vehicles, which do not have waste heat, as well as vehicles driven by a fuel cell. The authors of this paper observed that such an AHP system using ambient air as a heat source could not meet the heat requirement of the compartment when ambient temperature was extremely low. The reason is the decrease in the amount of heat taken from the ambient air as a result of low evaporating temperatures. Furthermore, the moisture condensed from air freezed on the evaporator surface, thus blocking the air flow through it. This problem can be solved by using the heat of engine coolant or exhaust gases. In this case, the AHP system can have a higher heating capacity and reuse waste heat. (author)

  13. Accounting engineering for sustainable development

    Directory of Open Access Journals (Sweden)

    Sidornya A.

    2017-01-01

    Full Text Available The article deals with the sustainable development of industrial enterprises in Russia, accounting for sustainable industrial growth of the national economy, tools of accounting engineering aimed at creating an information basis of transformation the Russian economic model to knowledge based economy. The proposed mechanism of ownership control of industrial enterprises in the context of long-term planning of the national economy. Theoretical bases of accounting engineering, its tools are defined. A brief review of the literature on the problem of accounting engineering is provided. A practical example of the application of the accounting engineering logic for the industrial enterprise is reviewed. It describes the research results obtained during the last 25 years of Russian scientific school of accounting engineering. Conclusions and recommendations on the use of accounting engineering to sustainable development of the Russian economy are formulated.

  14. Endoreversible quantum heat engines in the linear response regime.

    Science.gov (United States)

    Wang, Honghui; He, Jizhou; Wang, Jianhui

    2017-07-01

    We analyze general models of quantum heat engines operating a cycle of two adiabatic and two isothermal processes. We use the quantum master equation for a system to describe heat transfer current during a thermodynamic process in contact with a heat reservoir, with no use of phenomenological thermal conduction. We apply the endoreversibility description to such engine models working in the linear response regime and derive expressions of the efficiency and the power. By analyzing the entropy production rate along a single cycle, we identify the thermodynamic flux and force that a linear relation connects. From maximizing the power output, we find that such heat engines satisfy the tight-coupling condition and the efficiency at maximum power agrees with the Curzon-Ahlborn efficiency known as the upper bound in the linear response regime.

  15. Irreversible thermodynamic analysis and application for molecular heat engines

    Science.gov (United States)

    Lucia, Umberto; Açıkkalp, Emin

    2017-09-01

    Is there a link between the macroscopic approach to irreversibility and microscopic behaviour of the systems? Consumption of free energy keeps the system away from a stable equilibrium. Entropy generation results from the redistribution of energy, momentum, mass and charge. This concept represents the essence of the thermodynamic approach to irreversibility. Irreversibility is the result of the interaction between systems and their environment. The aim of this paper is to determine lost works in a molecular engine and compare results with macro (classical) heat engines. Firstly, irreversible thermodynamics are reviewed for macro and molecular cycles. Secondly, irreversible thermodynamics approaches are applied for a quantum heat engine with -1/2 spin system. Finally, lost works are determined for considered system and results show that macro and molecular heat engines obey same limitations. Moreover, a quantum thermodynamic approach is suggested in order to explain the results previously obtained from an atomic viewpoint.

  16. Automotive Stirling Engine Development Project

    Science.gov (United States)

    Ernst, William D.; Shaltens, Richard K.

    1997-01-01

    The development and verification of automotive Stirling engine (ASE) component and system technology is described as it evolved through two experimental engine designs: the Mod 1 and the Mod 2. Engine operation and performance and endurance test results for the Mod 1 are summarized. Mod 2 engine and component development progress is traced from the original design through hardware development, laboratory test, and vehicle installation. More than 21,000 hr of testing were accomplished, including 4800 hr with vehicles that were driven more dm 59,000 miles. Mod 2 engine dynamometer tests demonstrated that the engine system configuration had accomplished its performance goals for power (60 kW) and efficiency (38.5%) to within a few percent. Tests with the Mod 2 engine installed in a delivery van demonstrated combined metro-highway fuel economy improvements consistent with engine performance goals and the potential for low emission levels. A modified version of the Mod 2 has been identified as a manufacturable design for an ASE. As part of the ASE project, the Industry Test and Evaluation Program (ITEP), NASA Technology Utilization (TU) project, and the industry-funded Stirling Natural Gas Engine program were undertaken to transfer ASE technology to end users. The results of these technology transfer efforts are also summarized.

  17. Comparison of a Novel Organic-Fluid Thermofluidic Heat Converter and an Organic Rankine Cycle Heat Engine

    Directory of Open Access Journals (Sweden)

    Christoph J.W. Kirmse

    2016-06-01

    Full Text Available The Up-THERM heat converter is an unsteady, two-phase thermofluidic oscillator that employs an organic working fluid, which is currently being considered as a prime-mover in small- to medium-scale combined heat and power (CHP applications. In this paper, the Up-THERM heat converter is compared to a basic (sub-critical, non-regenerative organic Rankine cycle (ORC heat engine with respect to their power outputs, thermal efficiencies and exergy efficiencies, as well as their capital and specific costs. The study focuses on a pre-specified Up-THERM design in a selected application, a heat-source temperature range from 210 °C to 500 °C and five different working fluids (three n-alkanes and two refrigerants. A modeling methodology is developed that allows the above thermo-economic performance indicators to be estimated for the two power-generation systems. For the chosen applications, the power output of the ORC engine is generally higher than that of the Up-THERM heat converter. However, the capital costs of the Up-THERM heat converter are lower than those of the ORC engine. Although the specific costs (£/kW of the ORC engine are lower than those of the Up-THERM converter at low heat-source temperatures, the two systems become progressively comparable at higher temperatures, with the Up-THERM heat converter attaining a considerably lower specific cost at the highest heat-source temperatures considered.

  18. Heat exchanger operation in the externally heated air valve engine with separated settling chambers

    International Nuclear Information System (INIS)

    Kazimierski, Zbyszko; Wojewoda, Jerzy

    2014-01-01

    The crucial role in the externally heated air valve engine is played by its heat exchangers which work in a closed cycle. These are: a heater and a cooler and they are subject to a numerical analysis in the paper. Both of them are equipped with fixed volumes that are separate settling chambers causing that heat exchangers behave as almost stationary recuperators and analysis of the stationary behaviour is the main goal of the paper. Power and efficiency of the engine must be not lower than their averaged values for the same engine working in unsteady conditions. The results of calculations confirm such a statement. The pressure drop in the exchanger is another natural phenomenon presented. It has been overcome by use of additional blowers and the use of them is an additional focus of the presented analysis. A separation of settling chambers and additional blowers is a novelty in the paper. There is also a pre-heater applied in the engine which does not differ from well-known heat exchangers met in energy generation devices. The main objective of the paper is to find the behaviour of the engine model under stationary conditions of the heat exchangers and compare it with the non-stationary ones. - Highlights: • Externally heated air engine combined with forced working gas flow (supercharging). • Separate settling chambers allow for achieving stable and constant heat exchange parameters. • Pressure drop in heat exchangers overcome by additional blowers. • Reciprocating piston air engine, cam governing system, standard lubrication for externally heated engine. • Different fuels: oil, coal, gas, biomass also solar or nuclear energy

  19. Gradient heat flux measurement as monitoring method for the diesel engine

    Science.gov (United States)

    Sapozhnikov, S. Z.; Mityakov, V. Yu; Mityakov, A. V.; Vintsarevich, A. V.; Pavlov, A. V.; Nalyotov, I. D.

    2017-11-01

    The usage of gradient heat flux measurement for monitoring of heat flux on combustion chamber surface and optimization of diesel work process is proposed. Heterogeneous gradient heat flux sensors can be used at various regimes for an appreciable length of time. Fuel injection timing is set by the position of the maximum point on the angular heat flux diagram however, the value itself of the heat flux may not be considered. The development of such an approach can be productive for remote monitoring of work process in the cylinders of high-power marine engines.

  20. Heat Transfer in Two-Stroke Diesel Engines for Large Ship Propulsion

    DEFF Research Database (Denmark)

    Christiansen, Caspar Ask

    Demands on reducing the fuel consumption and harmful emissions from the compression ignition engines (diesel engines) have been continuously increasing in recent years. To comply with this, better modeling tools for the diesel combustion process are desired from the engine developers. A very......%, 30% and 50% load) was performed on a MAN Diesel & Turbo SE test engine, which shows very promising results for further investigations of dynamic temperature and heat flux in large bore engines. Instantaneous heat flux is derived using both an analytical and a numerical model and compared. More...... was investigated by computer simulations using a 3-D numerical finite volume model made in STAR-CD. General trends are observed from the temperature measurements in the limited part load range. These include among others: local increase in mean surface temperature and mean surface heat flux with increasing load...

  1. Nanoscale magnetic heat pumps and engines

    NARCIS (Netherlands)

    Bauer, G.E.W.; Bretzel, S.; Brataas, A.; Tserkovnyak, Y.

    2010-01-01

    We present the linear-response matrix for a sliding domain wall in a rotatable magnetic nanowire, which is driven out of equilibrium by temperature and voltage bias, mechanical torque, and magnetic field. An expression for heat-current-induced domain-wall motion is derived. Application of Onsager’s

  2. Dual Expander Cycle Rocket Engine with an Intermediate, Closed-cycle Heat Exchanger

    Science.gov (United States)

    Greene, William D. (Inventor)

    2008-01-01

    A dual expander cycle (DEC) rocket engine with an intermediate closed-cycle heat exchanger is provided. A conventional DEC rocket engine has a closed-cycle heat exchanger thermally coupled thereto. The heat exchanger utilizes heat extracted from the engine's fuel circuit to drive the engine's oxidizer turbomachinery.

  3. Quantum heat engine operating between thermal and spin reservoirs

    Science.gov (United States)

    Wright, Jackson S. S. T.; Gould, Tim; Carvalho, André R. R.; Bedkihal, Salil; Vaccaro, Joan A.

    2018-05-01

    Landauer's erasure principle is a cornerstone of thermodynamics and information theory [R. Landauer, IBM J. Res. Dev. 5, 183 (1961), 10.1147/rd.53.0183]. According to this principle, erasing information incurs a minimum energy cost. Recently, Vaccaro and Barnett [J. A. Vaccaro and S. M. Barnett, Proc. R. Soc. A 467, 1770 (2011), 10.1098/rspa.2010.0577] explored information erasure in the context of multiple conserved quantities and showed that the erasure cost can be solely in terms of spin angular momentum. As Landauer's erasure principle plays a fundamental role in heat engines, their result considerably widens the possible configurations that heat engines can have. Motivated by this, we propose here an optical heat engine that operates under a single thermal reservoir and a spin angular momentum reservoir coupled to a three-level system with two energy degenerate ground states. The proposed heat engine operates without producing waste heat and goes beyond the traditional Carnot engine where the working fluid is subjected to two thermal baths at different temperatures.

  4. Design of Heat Exchanger for Ericsson-Brayton Piston Engine

    Directory of Open Access Journals (Sweden)

    Peter Durcansky

    2014-01-01

    Full Text Available Combined power generation or cogeneration is a highly effective technology that produces heat and electricity in one device more efficiently than separate production. Overall effectiveness is growing by use of combined technologies of energy extraction, taking heat from flue gases and coolants of machines. Another problem is the dependence of such devices on fossil fuels as fuel. For the combustion turbine is mostly used as fuel natural gas, kerosene and as fuel for heating power plants is mostly used coal. It is therefore necessary to seek for compensation today, which confirms the assumption in the future. At first glance, the obvious efforts are to restrict the use of largely oil and change the type of energy used in transport. Another significant change is the increase in renewable energy—energy that is produced from renewable sources. Among machines gaining energy by unconventional way belong mainly the steam engine, Stirling engine, and Ericsson engine. In these machines, the energy is obtained by external combustion and engine performs work in a medium that receives and transmits energy from combustion or flue gases indirectly. The paper deals with the principle of hot-air engines, and their use in combined heat and electricity production from biomass and with heat exchangers as primary energy transforming element.

  5. Design of heat exchanger for Ericsson-Brayton piston engine.

    Science.gov (United States)

    Durcansky, Peter; Papucik, Stefan; Jandacka, Jozef; Holubcik, Michal; Nosek, Radovan

    2014-01-01

    Combined power generation or cogeneration is a highly effective technology that produces heat and electricity in one device more efficiently than separate production. Overall effectiveness is growing by use of combined technologies of energy extraction, taking heat from flue gases and coolants of machines. Another problem is the dependence of such devices on fossil fuels as fuel. For the combustion turbine is mostly used as fuel natural gas, kerosene and as fuel for heating power plants is mostly used coal. It is therefore necessary to seek for compensation today, which confirms the assumption in the future. At first glance, the obvious efforts are to restrict the use of largely oil and change the type of energy used in transport. Another significant change is the increase in renewable energy--energy that is produced from renewable sources. Among machines gaining energy by unconventional way belong mainly the steam engine, Stirling engine, and Ericsson engine. In these machines, the energy is obtained by external combustion and engine performs work in a medium that receives and transmits energy from combustion or flue gases indirectly. The paper deals with the principle of hot-air engines, and their use in combined heat and electricity production from biomass and with heat exchangers as primary energy transforming element.

  6. Ceramic technology for advanced heat engines project: Semiannual progress report for April through September 1986

    Energy Technology Data Exchange (ETDEWEB)

    1987-03-01

    An assessment of needs was completed, and a five-year project plan was developed with extensive input from private industry. Objective is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines.

  7. A thermoacoustic-Stirling heat engine: detailed study

    Science.gov (United States)

    Backhaus; Swift

    2000-06-01

    A new type of thermoacoustic engine based on traveling waves and ideally reversible heat transfer is described. Measurements and analysis of its performance are presented. This new engine outperforms previous thermoacoustic engines, which are based on standing waves and intrinsically irreversible heat transfer, by more than 50%. At its most efficient operating point, it delivers 710 W of acoustic power to its resonator with a thermal efficiency of 0.30, corresponding to 41% of the Carnot efficiency. At its most powerful operating point, it delivers 890 W to its resonator with a thermal efficiency of 0.22. The efficiency of this engine can be degraded by two types of acoustic streaming. These are suppressed by appropriate tapering of crucial surfaces in the engine and by using additional nonlinearity to induce an opposing time-averaged pressure difference. Data are presented which show the nearly complete elimination of the streaming convective heat loads. Analysis of these and other irreversibilities show which components of the engine require further research to achieve higher efficiency. Additionally, these data show that the dynamics and acoustic power flows are well understood, but the details of the streaming suppression and associated heat convection are only qualitatively understood.

  8. A thermoacoustic-Stirling heat engine: Detailed study

    International Nuclear Information System (INIS)

    Backhaus, S.; Swift, G. W.

    2000-01-01

    A new type of thermoacoustic engine based on traveling waves and ideally reversible heat transfer is described. Measurements and analysis of its performance are presented. This new engine outperforms previous thermoacoustic engines, which are based on standing waves and intrinsically irreversible heat transfer, by more than 50%. At its most efficient operating point, it delivers 710 W of acoustic power to its resonator with a thermal efficiency of 0.30, corresponding to 41% of the Carnot efficiency. At its most powerful operating point, it delivers 890 W to its resonator with a thermal efficiency of 0.22. The efficiency of this engine can be degraded by two types of acoustic streaming. These are suppressed by appropriate tapering of crucial surfaces in the engine and by using additional nonlinearity to induce an opposing time-averaged pressure difference. Data are presented which show the nearly complete elimination of the streaming convective heat loads. Analysis of these and other irreversibilities show which components of the engine require further research to achieve higher efficiency. Additionally, these data show that the dynamics and acoustic power flows are well understood, but the details of the streaming suppression and associated heat convection are only qualitatively understood. (c) 2000 Acoustical Society of America

  9. Gas engine driven freon-free heat supply system complying with multiple fuels (eco-energy city project)

    Energy Technology Data Exchange (ETDEWEB)

    Yagyu, Sumio; Maekawa, Koich; Sugawara, Koich; Hayashida, Masaru; Fujishima, Ichiro; Fukuyama, Yuji; Morikawa, Tomoyuki; Yamato, Tadao; Obata, Norio [Advanced Technology Lab., Kubota Corp., Amagasaki, Hyogo (Japan)

    1999-07-01

    This paper describes recent results at Kubota to develop a gas engine driven freon-free heat supply system. Utilizing a gas mixture which consists of CO and H{sub 2} supplied from a broad area energy utilization network, the system produces four heat sources (263 K, 280 K, 318 K, and 353 K) for air-conditioning, hot water supply, and refrigeration in a single system. It also conforms to fuel systems that utilize methane and hydrogen. This multi-functional heat supply system is composed of an efficient gas engine (methanol gas engine) and a freon-free heat pump (heat-assisted Stirling heat pump). The heat-assisted Stirling heat pump is mainly driven by engine shaft power and is partially assisted by thermal power provided by engine exhaust heat. By proportioning the two energy sources to match the characteristics of the driving engine, the heat pump is supplied with the maximum share of the original energy fueling the engine. Developing the system will establish freon-free thermal utilization system technology that satisfies both wide heat demands and various fuel systems. (orig.)

  10. KSTAR RF heating system development

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, J. G.; Kim, S. K.; Hwang, C. K. (and others)

    2007-10-15

    Design, high-voltage test, and installation of 6 MW ICRF heating system for KSTAR is completed. The antenna demonstrated satisfactory standoff at high voltages up to 41 kV for 300 sec. The result indicates good power handling capabilities of the antenna as high as 10 MW/m2. This power density is equivalent to RF power coupling of 6 MW into a 4 {omega}/m target plasma, and is typical of advanced tokamak heating scenarios. In addition, vacuum feed through, DC break, and liquid stub developed for 300 sec operation are installed, as well as a 2 MW, 30-60MHz transmitter. The transmitter successfully produced output powers of 600 kW continuously, 1.5{approx}1.8 MW for 300 sec, and 2 MW for 100 msec or shorter pulses. A realtime control system based on DSP and EPICS is developed, installed, and tested on the ICRF system. Initial results from feasibility study indicate that the present antenna and the transmission lines could allow load-resilient operation on KSTAR. Until the KSTAR tokamak start to produce plasmas in 2008, however, hands-on operational experiences are obtained from participating in ICRF heating experiments at ASDEX and DIII-D tokamaks arranged through international cooperation.

  11. Educating Engineers for Sustainable Development

    DEFF Research Database (Denmark)

    Myrdal, Christina Grann; Holgaard, Jette Egelund

    In this paper, we explore the potentials of designing engineering education activities for sustainability development based on how environmental concerns are integrated into product development processes in a company context. First we draw on a case study from the Danish company Grundfos Management...... A/S and based on their experience with product development practise and competence development of product developers, we propose a set of competences to be addressed in engineering education for sustainable development (EESD). Furthermore, we use the problem based learning philosophy as a base...

  12. Optimization of solar-powered Stirling heat engine with finite-time thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Yaqi, Li [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Xi' an Research Institute of Hi-Tech, Xi' an, Shaanxi 710025 (China); Yaling, He; Weiwei, Wang [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China)

    2011-01-15

    A mathematical model for the overall thermal efficiency of the solar-powered high temperature differential dish-Stirling engine with finite-rate heat transfer, regenerative heat losses, conductive thermal bridging losses and finite regeneration processes time is developed. The model takes into consideration the effect of the absorber temperature and the concentrating ratio on the thermal efficiency; radiation and convection heat transfer between the absorber and the working fluid as well as convection heat transfer between the heat sink and the working fluid. The results show that the optimized absorber temperature and concentrating ratio are at about 1100 K and 1300, respectively. The thermal efficiency at optimized condition is about 34%, which is not far away from the corresponding Carnot efficiency at about 50%. Hence, the present analysis provides a new theoretical guidance for designing dish collectors and operating the Stirling heat engine system. (author)

  13. Development of heat flux sensors for turbine airfoils

    Science.gov (United States)

    Atkinson, William H.; Cyr, Marcia A.; Strange, Richard R.

    1985-10-01

    The objectives of this program are to develop heat flux sensors suitable for installation in hot section airfoils of advanced aircraft turbine engines and to experimentally verify the operation of these heat flux sensors in a cylinder in a cross flow experiment. Embedded thermocouple and Gardon gauge sensors were developed and fabricated into both blades and vanes. These were then calibrated using a quartz lamp bank heat source and finally subjected to thermal cycle and thermal soak testing. These sensors were also fabricated into cylindrical test pieces and tested in a burner exhaust to verify heat flux measurements produced by these sensors. The results of the cylinder in cross flow tests are given.

  14. Development of heat flux sensors for turbine airfoils

    Science.gov (United States)

    Atkinson, William H.; Cyr, Marcia A.; Strange, Richard R.

    1985-01-01

    The objectives of this program are to develop heat flux sensors suitable for installation in hot section airfoils of advanced aircraft turbine engines and to experimentally verify the operation of these heat flux sensors in a cylinder in a cross flow experiment. Embedded thermocouple and Gardon gauge sensors were developed and fabricated into both blades and vanes. These were then calibrated using a quartz lamp bank heat source and finally subjected to thermal cycle and thermal soak testing. These sensors were also fabricated into cylindrical test pieces and tested in a burner exhaust to verify heat flux measurements produced by these sensors. The results of the cylinder in cross flow tests are given.

  15. Finite-size effect on optimal efficiency of heat engines.

    Science.gov (United States)

    Tajima, Hiroyasu; Hayashi, Masahito

    2017-07-01

    The optimal efficiency of quantum (or classical) heat engines whose heat baths are n-particle systems is given by the strong large deviation. We give the optimal work extraction process as a concrete energy-preserving unitary time evolution among the heat baths and the work storage. We show that our optimal work extraction turns the disordered energy of the heat baths to the ordered energy of the work storage, by evaluating the ratio of the entropy difference to the energy difference in the heat baths and the work storage, respectively. By comparing the statistical mechanical optimal efficiency with the macroscopic thermodynamic bound, we evaluate the accuracy of the macroscopic thermodynamics with finite-size heat baths from the statistical mechanical viewpoint. We also evaluate the quantum coherence effect on the optimal efficiency of the cycle processes without restricting their cycle time by comparing the classical and quantum optimal efficiencies.

  16. Work and power fluctuations in a critical heat engine

    Science.gov (United States)

    Holubec, Viktor; Ryabov, Artem

    2017-09-01

    We investigate fluctuations of output work for a class of Stirling heat engines with working fluid composed of interacting units and compare these fluctuations to an average work output. In particular, we focus on engine performance close to a critical point where Carnot's efficiency may be attained at a finite power as reported by M. Campisi and R. Fazio [Nat. Commun. 7, 11895 (2016), 10.1038/ncomms11895]. We show that the variance of work output per cycle scales with the same critical exponent as the heat capacity of the working fluid. As a consequence, the relative work fluctuation diverges unless the output work obeys a rather strict scaling condition, which would be very hard to fulfill in practice. Even under this condition, the fluctuations of work and power do not vanish in the infinite system size limit. Large fluctuations of output work thus constitute inseparable and dominant element in performance of the macroscopic heat engines close to a critical point.

  17. Work and power fluctuations in a critical heat engine.

    Science.gov (United States)

    Holubec, Viktor; Ryabov, Artem

    2017-09-01

    We investigate fluctuations of output work for a class of Stirling heat engines with working fluid composed of interacting units and compare these fluctuations to an average work output. In particular, we focus on engine performance close to a critical point where Carnot's efficiency may be attained at a finite power as reported by M. Campisi and R. Fazio [Nat. Commun. 7, 11895 (2016)2041-172310.1038/ncomms11895]. We show that the variance of work output per cycle scales with the same critical exponent as the heat capacity of the working fluid. As a consequence, the relative work fluctuation diverges unless the output work obeys a rather strict scaling condition, which would be very hard to fulfill in practice. Even under this condition, the fluctuations of work and power do not vanish in the infinite system size limit. Large fluctuations of output work thus constitute inseparable and dominant element in performance of the macroscopic heat engines close to a critical point.

  18. Determination and Application of Comprehensive Specific Frictional Resistance in Heating Engineering

    Directory of Open Access Journals (Sweden)

    Yanan Tian

    2018-01-01

    Full Text Available In this study, we analyze the deficiencies of specific frictional resistance in heating engineering. Based on economic specific frictional resistance, we put forward the concept of comprehensive specific frictional resistance, which considers the multiple factors of technology, economy, regulation modes, pipe segment differences, and medium pressure. Then, we establish a mathematical model of a heating network across its lifespan in order to develop a method for determining the comprehensive specific frictional resistance. Relevant conclusions can be drawn from the results. As an application, we have planned the heating engineering for Yangyuan County in China, which demonstrates the feasibility and superiority of the method.

  19. Heat Transfer in Large Two-Stroke Marine Diesel Engines

    DEFF Research Database (Denmark)

    Jensen, Michael Vincent

    Heat transfer between the cylinder gas and the piston surface during combustion in large two-stroke uniflow scavenged marine diesel engines has been investigated in the present work. The piston surface experiences a severe thermal load during combustion due to the close proximity of the combustion...... zone to the surface. At the same time, cooling of the piston crown is relatively complicated. This can cause large thermal stresses in the piston crown and weakening of the material strength, which may be critical as it can lead to formation of cracks. Information about the piston surface heat transfer...... is thus important for the engine manufactures. The piston surface heat transfer was studied in the event of impingement of hot combustion products on the piston during combustion, and an estimate was obtained of the peak heat flux level experienced on the piston surface. The investigation was carried out...

  20. Thermodynamic and heat transfer analysis of heat recovery from engine test cell by Organic Rankine Cycle

    Science.gov (United States)

    Shokati, Naser; Mohammadkhani, Farzad; Farrokhi, Navid; Ranjbar, Faramarz

    2014-12-01

    During manufacture of engines, evaluation of engine performance is essential. This is accomplished in test cells. During the test, a significant portion of heat energy released by the fuel is wasted. In this study, in order to recover these heat losses, Organic Rankine Cycle (ORC) is recommended. The study has been conducted assuming the diesel oil to be composed of a single hydrocarbon such as C12H26. The composition of exhaust gases (products of combustion) have been computed (and not determined experimentally) from the stoichiometric equation representing the combustion reaction. The test cell heat losses are recovered in three separate heat exchangers (preheater, evaporator and superheater). These heat exchangers are separately designed, and the whole system is analyzed from energy and exergy viewpoints. Finally, a parametric study is performed to investigate the effect of different variables on the system performance characteristics such as the ORC net power, heat exchangers effectiveness, the first law efficiency, exergy destruction and heat transfer surfaces. The results of the study show that by utilizing ORC, heat recovery equivalent to 8.85 % of the engine power is possible. The evaporator has the highest exergy destruction rate, while the pump has the lowest among the system components. Heat transfer surfaces are calculated to be 173.6, 58.7, and 11.87 m2 for the preheater, evaporator and superheater, respectively.

  1. An analysis of geothermal heating and engineering cost in Tianjin, China

    International Nuclear Information System (INIS)

    Wang, W.

    1990-01-01

    Tianjin is a region with fairly rich low-temperature geothermal resources. Its climate and soaring price of raw coals have made geo heating in Tianjin develop rapidly over the past 5 years. The types of heating systems fall into 3 categories and the primary factors for using temperature drop are 5. According to economical analysis, the optimal discharge temperature in the space heating is about 43 degrees C and the minimum discharge temperature 35 degrees C approximately. This paper reports that an analysis of a typical engineering costs involved shows that the advantages of geo space heating are not notable when compared with burning coals. However, to reduce air pollution, the state and general public are ready to support the development of such geothermal wells as deep as 3,000 m for space heating irrespective of their sole engineering costs

  2. Quantum Heat Engine and Negative Boltzmann Temperature

    International Nuclear Information System (INIS)

    Xi Jing-Yi; Quan Hai-Tao

    2017-01-01

    To clarify the ambiguity on negative Boltzmann temperature in literature, we study the Carnot and the Otto cycle with one of the heat reservoirs at the negative Boltzmann temperature based on a canonical ensemble description. The work extraction, entropy production and the efficiency of these cycles are explored. Conditions for constructing and properties of these thermodynamic cycles are elucidated. We find that the apparent “violation” of the second law of thermodynamics in these cycles are due to the fact that the traditional definition of thermodynamic efficiency is inappropriate in this situation. When properly understanding the efficiency and the adiabatic processes, in which the system crosses over “absolute ZERO” in a limit sense, the Carnot cycle with one of the heat reservoirs at a negative Boltzmann temperature can be understood straightforwardly, and it contradicts neither the second nor the third law of thermodynamics. Hence, negative Boltzmann temperature is a consistent concept in thermodynamics. We use a two-level system and an Ising spin system to illustrate our central results. (paper)

  3. Nonstationary heat flow in the piston of the turbocharged engine

    Directory of Open Access Journals (Sweden)

    Piotr GUSTOF

    2010-01-01

    Full Text Available In this study the numeric computations of nonstationary heat flow in form of temperature distribution on characteristic surfaces of the piston of the turbocharged engine at the beginning phase its work was presented. The computations were performed for fragmentary load engine by means of the two-zone combustion model, the boundary conditions of III kind and the finite elements method (FEM by using of COSMOS/M program.

  4. Heat Transfer and Fluid Dynamics Measurements in the Expansion Space of a Stirling Cycle Engine

    Science.gov (United States)

    Jiang, Nan; Simon, Terrence W.

    2006-01-01

    The heater (or acceptor) of a Stirling engine, where most of the thermal energy is accepted into the engine by heat transfer, is the hottest part of the engine. Almost as hot is the adjacent expansion space of the engine. In the expansion space, the flow is oscillatory, impinging on a two-dimensional concavely-curved surface. Knowing the heat transfer on the inside surface of the engine head is critical to the engine design for efficiency and reliability. However, the flow in this region is not well understood and support is required to develop the CFD codes needed to design modern Stirling engines of high efficiency and power output. The present project is to experimentally investigate the flow and heat transfer in the heater head region. Flow fields and heat transfer coefficients are measured to characterize the oscillatory flow as well as to supply experimental validation for the CFD Stirling engine design codes. Presented also is a discussion of how these results might be used for heater head and acceptor region design calculations.

  5. Heat recovery from a cement plant with a Marnoch Heat Engine

    International Nuclear Information System (INIS)

    Saneipoor, P.; Naterer, G.F.; Dincer, I.

    2011-01-01

    This paper examines the performance of a new Marnoch Heat Engine (MHE) that recovers waste heat from within a typical cement plant. Two MHE units with compressed air as the working fluid are installed to recover the waste heat. The first unit on the main stack has four pairs of shell and tube heat exchangers. The second heat recovery unit is installed on a clinker quenching system. This unit operates with three pairs of shell and tube heat exchangers. The recovered heat is converted to electricity through the MHE system and used internally within the cement plant. A predictive model and results are presented and discussed. The results show the promising performance of the MHE's capabilities for efficient generation of electricity from waste heat sources in a cement plant. The new heat recovery system increases the efficiency of the cement plant and lowers the CO 2 emissions from the clinker production process. Moreover, it reduces the amount of waste heat to the environment and lowers the temperature of the exhaust gases. - Highlights: → This paper examines the thermodynamic performance of a new Marnoch Heat Engine (MHE) that recovers waste heat to produce electricity and improve the operating efficiency of a typical cement plant. → The first unit of the MHE on the main stack has four pairs of shell and tube heat exchangers and the second heat recovery unit is installed on a clinker quenching system. → Both predicted and experimental results demonstrate the promising performance of the MHE's capabilities for efficient generation of electricity from waste heat sources in a cement plant.

  6. Waste Heat Recovery from a High Temperature Diesel Engine

    Science.gov (United States)

    Adler, Jonas E.

    Government-mandated improvements in fuel economy and emissions from internal combustion engines (ICEs) are driving innovation in engine efficiency. Though incremental efficiency gains have been achieved, most combustion engines are still only 30-40% efficient at best, with most of the remaining fuel energy being rejected to the environment as waste heat through engine coolant and exhaust gases. Attempts have been made to harness this waste heat and use it to drive a Rankine cycle and produce additional work to improve efficiency. Research on waste heat recovery (WHR) demonstrates that it is possible to improve overall efficiency by converting wasted heat into usable work, but relative gains in overall efficiency are typically minimal ( 5-8%) and often do not justify the cost and space requirements of a WHR system. The primary limitation of the current state-of-the-art in WHR is the low temperature of the engine coolant ( 90 °C), which minimizes the WHR from a heat source that represents between 20% and 30% of the fuel energy. The current research proposes increasing the engine coolant temperature to improve the utilization of coolant waste heat as one possible path to achieving greater WHR system effectiveness. An experiment was performed to evaluate the effects of running a diesel engine at elevated coolant temperatures and to estimate the efficiency benefits. An energy balance was performed on a modified 3-cylinder diesel engine at six different coolant temperatures (90 °C, 100 °C, 125 °C, 150 °C, 175 °C, and 200 °C) to determine the change in quantity and quality of waste heat as the coolant temperature increased. The waste heat was measured using the flow rates and temperature differences of the coolant, engine oil, and exhaust flow streams into and out of the engine. Custom cooling and engine oil systems were fabricated to provide adequate adjustment to achieve target coolant and oil temperatures and large enough temperature differences across the

  7. LDUA engineering development plan

    International Nuclear Information System (INIS)

    Engstrom, J.W.

    1994-01-01

    This document provides guidance to perform Light Duty Utility Arm (LDUA) development work and documentation required to validate the design of the LDUA System.The LDUA system will be used to deploy various types of sensors and devices to demonstrate the technology and qualify the integrated systems for operational use in the Hanford single shell tanks to characterize the waste inside and assess tank integrity

  8. VHTR engineering design study: intermediate heat exchanger program. Final report

    International Nuclear Information System (INIS)

    1976-11-01

    The work reported is the result of a follow-on program to earlier Very High Temperature Reactor (VHTR) studies. The primary use of the VHTR is to provide heat for various industrial processes, such as hydrocarbon reforming and coal gasification. For many processes the use of an intermediate heat transfer barrier between the reactor coolant and the process is desirable; for some processes it is mandatory. Various intermediate heat exchanger (IHX) concepts for the VHTR were investigated with respect to safety, cost, and engineering design considerations. The reference processes chosen were steam-hydrocarbon reforming, with emphasis on the chemical heat pipe, and steam gasification of coal. The study investigates the critically important area of heat transfer between the reactor coolant, helium, and the various chemical processes

  9. Experimental study of gas engine driven air to water heat pump in cooling mode

    International Nuclear Information System (INIS)

    Elgendy, E.; Schmidt, J.

    2010-01-01

    Nowadays a sustainable development for more efficient use of energy and protection of the environment is of increasing importance. Gas engine heat pumps represent one of the most practicable solutions which offer high energy efficiency and environmentally friendly for heating and cooling applications. In this paper, the performance characteristics of gas engine driven heat pump used in water cooling were investigated experimentally without engine heat recovery. The effects of several important factors (evaporator water inlet temperature, evaporator water volume flow rate, ambient air temperature, and engine speed) on the performance of gas engine driven heat pump were studied in a wide range of operating conditions. The results showed that primary energy ratio of the system increased by 22.5% as evaporator water inlet temperature increased from 13 o C to 24 o C. On the other hand, varying of engine speed from 1300 rpm to 1750 rpm led to decrease in system primary energy ratio by 13%. Maximum primary energy ratio has been estimated with a value of two over a wide range of operating conditions.

  10. Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

    International Nuclear Information System (INIS)

    Shehata, M.S.

    2010-01-01

    An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the sours of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio γ(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating γ(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio γ(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and LPG due to high

  11. Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Shehata, M.S. [Mechanical Engineering Technology Department, Higher Institute of Technology, Banha University, 4Zagalol Street, Benha, Galubia 1235 Z (Egypt)

    2010-12-15

    An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the source of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio {gamma}(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating {gamma}(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio {gamma}(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and

  12. Optimal Control of Diesel Engines with Waste Heat Recovery System

    NARCIS (Netherlands)

    Willems, F.P.T.; Donkers, M.C.F.; Kupper, F.

    2014-01-01

    This study presents an integrated energy and emission management strategy for a Euro-VI diesel engine with Waste Heat Recovery (WHR) system. This Integrated Powertrain Control (IPC) strategy optimizes the CO2-NOx trade-off by minimizing the operational costs associated with fuel and AdBlue

  13. Optimal control of diesel engines with waste heat recovery systems

    NARCIS (Netherlands)

    Willems, F.P.T.; Donkers, M.C.F.; Kupper, F.; Waschl, H.; Kolmanovsky, I.; Steinbuch, M.; Del Re, L.

    2014-01-01

    This study presents an integrated energy and emission management strategy for a Euro-VI diesel engine with Waste Heat Recovery (WHR) system. This Integrated Powertrain Control (IPC) strategy optimizes the CO 2 - NO x trade-off by minimizing the operational costs associated with fuel and AdBlue

  14. Engineering research, development and technology

    International Nuclear Information System (INIS)

    1994-05-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the technical staff, tools, and facilities needed to support current and future LLNL programs. The efforts are guided by a dual-benefit research and development strategy that supports Department of Energy missions, such as national security through nuclear deterrence and economic competitiveness through partnerships with U.S. industry. This annual report, organized by thrust area, describes the activities for the fiscal year 1993. The report provides timely summaries of objectives, methods, and results from nine thrust areas for this fiscal year: Computational Electronics and Electromagnetics; Computational Mechanics; Diagnostics and Microelectronics; Fabrication Technology; Materials Science and Engineering; Power Conversion Technologies; Nondestructive Evaluation; Remote Sensing, Imaging, and Signal Engineering; and Emerging Technologies. Separate abstracts were prepared for 47 papers in this report

  15. Performance analysis of a thermosize micro/nano heat engine

    International Nuclear Information System (INIS)

    Nie Wenjie; He Jizhou

    2008-01-01

    In a recent paper [A. Sisman, I. Muller, Phys. Lett. A 320 (2004) 360] the thermodynamic properties of ideal gases confined in a narrow box were examined theoretically. The so-called 'thermosize effects' similar to thermoelectric effects, such as Seebeck-like thermosize effect, Peltier-like thermosize effect and Thomson-like thermosize effect, were analyzed. Like the thermoelectric generator, based on the thermosize effects we have established a model of micro/nano scaled ideal gas heat engine cycle which includes two isothermal and two isobaric processes. The expressions of power output and efficiency of this cycle in the two cases of reversible and irreversible heat exchange are derived and the optimal performance characteristics of the heat engine is discussed by some numerical example. The results obtained here will provide theoretical guidance for the design of micro/nano scaled device

  16. Analysis and assessment of a new organic Rankine based heat engine system with/without cogeneration

    International Nuclear Information System (INIS)

    Hogerwaard, Janette; Dincer, Ibrahim; Zamfirescu, Calin

    2013-01-01

    A low-temperature heat driven heat engine is proposed as a cost-effective system for power and heat production for small scale applications. The external heat source allows flexibility in the design; the system may be coupled with various available renewable sources including biomass/biofuel/biogas combustion, geothermal heat, concentrated solar radiation, and industrial waste heat, by selecting appropriate off-the-shelf components from the HVAC (heating, ventilation, and air conditioning), refrigeration, and automotive industries for use in an ORC (organic Rankine cycle). A theoretical analysis and an experimental study are carried out for an ORC with R134a as the working fluid, utilizing a low-temperature heat source (T source < 150 °C), with focus on the expansion and boiling processes. The complete ORC model is comprised of models for the expander, working fluid pump, boiler, and condenser. Thermodynamic and heat transfer models are developed to calculate the local and averaged heat transfer coefficient of the working fluid throughout the boiling process, based on the geometry of the selected heat exchanger. Data collected for the experimental ORC test bench are used to validate the expander and boiler models. A case study is performed for the proposed ORC, for cogeneration of power and heat in a residential application. The results of the case study analysis for the proposed ORC system indicate a cycle efficiency of 0.05, exergy efficiency of 0.17, and energy and exergy cogeneration efficiency of 0.87, and 0.35, respectively. - Highlights: • Development and investigation of a scroll based Rankine heat engine operating with R134a. • Thermodynamic analyses of the system and its components. • Heat transfer analyses of boiler and condenser. • Dynamic analysis of expander. • Model validation through performed experiments on an ORC test bench

  17. Thermodynamic analysis of the heat regenerative cycle in porous medium engine

    International Nuclear Information System (INIS)

    Liu Hongsheng; Xie Maozhao; Wu Dan

    2009-01-01

    The advantages of homogeneous combustion in internal combustion engines are well known all over the world. Recent years, porous medium (PM) engine has been proposed as a new type engine based on the technique of combustion in porous medium, which can fulfils all requirements to perform homogeneous combustion. In this paper, working processes of a PM engine are briefly introduced and an ideal thermodynamic model of the PM heat regeneration cycle in PM engine is developed. An expression for the relation between net work output and thermal efficiency is derived for the cycle. In order to evaluate of the cycle, the influences of the expansion ratio, initial temperature and limited temperature on the net work and efficiency are discussed, and the availability terms of the cycle are analyzed. Comparing the PM heat regenerative cycle of the PM engine against Otto cycle and Diesel cycle shows that PM heat regenerative cycle can improve net work output greatly with little drop of efficiency. The aim of this paper is to predict the thermodynamic performance of PM heat regeneration cycle and provide a guide to further investigations of the PM engine

  18. Heat engine in the three-dimensional spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Jie-Xiong [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Liang, Feng [Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Li, Gu-Qiang [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China)

    2017-03-02

    We define a kind of heat engine via three-dimensional charged BTZ black holes. This case is quite subtle and needs to be more careful. The heat flow along the isochores does not equal to zero since the specific heat C{sub V}≠0 and this point completely differs from the cases discussed before whose isochores and adiabats are identical. So one cannot simply apply the paradigm in the former literatures. However, if one introduces a new thermodynamic parameter associated with the renormalization length scale, the above problem can be solved. We obtain the analytical efficiency expression of the three-dimensional charged BTZ black hole heat engine for two different schemes. Moreover, we double check with the exact formula. Our result presents the first specific example for the sound correctness of the exact efficiency formula. We argue that the three-dimensional charged BTZ black hole can be viewed as a toy model for further investigation of holographic heat engine. Furthermore, we compare our result with that of the Carnot cycle and extend the former result to three-dimensional spacetime. In this sense, the result in this paper would be complementary to those obtained in four-dimensional spacetime or ever higher. Last but not the least, the heat engine efficiency discussed in this paper may serve as a criterion to discriminate the two thermodynamic approaches introduced in ref. https://www.doi.org/10.1103/PhysRevD.92.124069 and our result seems to support the approach which introduces a new thermodynamic parameter R=r{sub 0}.

  19. The study of the heat-engineering characteristics of a solar heat collector based on aluminum heat pipes

    International Nuclear Information System (INIS)

    Khairnasov, S.M.; Zaripov, V.K.; Passamakin, B.M. et al.

    2013-01-01

    This paper presents the results of studies into the heat-engineering characteristics of a flat heat solar collector based on aluminum heat pipes that is designed to be used in building facades. The principle of work and the structure of the solar collector are considered; the results of its comparison with a traditional flat solar collector are presented. The studies were performed at a heat carrier temperature range of +10 - +30 degree C and at a solar heat flow density of 400 - 1000 W/m 2 . The obtained experimental heat-engineering characteristics of the collector based on heat pipes show that they are at a level of traditional flow solar collectors; for example, its efficiency is 0.65 - 0.73. Meanwhile, the hydraulic resistance of the structure with heat pipes is by a factor of 2 - 2.4 smaller and ensures a high level of scalability, reliability, and maintainability, which is important when using it as an element of facade constructions of solar heat systems. (author)

  20. Heat transfer characteristics of some oils used for engine cooling

    International Nuclear Information System (INIS)

    Abou-Ziyan, Hosny Z.

    2004-01-01

    This paper reports the results of an experimental investigation of heat transfer from a cast iron test specimen to engine oils under boiling conditions. The work is aimed at evaluating the thermal characteristics of some engine oils in contact with high temperature parts in internal combustion engines. Three mono-grade oils and two multi-grade oils are examined at heat fluxes from about 30 to more than 400 kW/m 2 for bulk temperatures of 40, 60, 80, 100, 125, 150 and 175 deg. C. The considered oils are analyzed and tested according to some ASTM standards to determine their additives concentration and to obtain some of their thermophysical properties. The results indicated that oil additives, oil properties and bulk temperatures have substantial effects on the oil characteristics. The boiling heat flux, for the best oil, rises by a factor of 1.65 as the bulk temperature decreases from 175 to 40 deg. C. The mono-grade oils produce superior heat transfer characteristics compared to those produced by multi-grade oils. The oil with the best additive concentrations produces boiling heat fluxes up to 4.44 times higher than those produced by some other oils. Comparing the results of the tested oils revealed that the oil that has the largest concentrations of boron, magnesium, phosphorus and zinc with low concentration of calcium yields the best heat transport characteristics among the other tested oils. These additives provide superior detergent and dispersant characteristics, reflected in the large alkalinity and low corrosivity of the oil. On the other side, calcium has a negative interaction with other additives and yields an adverse effect on heat transfer characteristics even when it exists in oil with large concentrations of boron, magnesium, phosphorus and zinc

  1. Maximum Power Output of Quantum Heat Engine with Energy Bath

    Directory of Open Access Journals (Sweden)

    Shengnan Liu

    2016-05-01

    Full Text Available The difference between quantum isoenergetic process and quantum isothermal process comes from the violation of the law of equipartition of energy in the quantum regime. To reveal an important physical meaning of this fact, here we study a special type of quantum heat engine consisting of three processes: isoenergetic, isothermal and adiabatic processes. Therefore, this engine works between the energy and heat baths. Combining two engines of this kind, it is possible to realize the quantum Carnot engine. Furthermore, considering finite velocity of change of the potential shape, here an infinite square well with moving walls, the power output of the engine is discussed. It is found that the efficiency and power output are both closely dependent on the initial and final states of the quantum isothermal process. The performance of the engine cycle is shown to be optimized by control of the occupation probability of the ground state, which is determined by the temperature and the potential width. The relation between the efficiency and power output is also discussed.

  2. An Engineering Aerodynamic Heating Method for Hypersonic Flow

    Science.gov (United States)

    Riley, Christopher J.; DeJarnette, Fred R.

    1992-01-01

    A capability to calculate surface heating rates has been incorporated in an approximate three-dimensional inviscid technique. Surface streamlines are calculated from the inviscid solution, and the axisymmetric analog is then used along with a set of approximate convective-heating equations to compute the surface heat transfer. The method is applied to blunted axisymmetric and three-dimensional ellipsoidal cones at angle of attack for the laminar flow of a perfect gas. The method is also applicable to turbulent and equilibrium-air conditions. The present technique predicts surface heating rates that compare favorably with experimental (ground-test and flight) data and numerical solutions of the Navier-Stokes (NS) and viscous shock-layer (VSL) equations. The new technique represents a significant improvement over current engineering aerothermal methods with only a modest increase in computational effort.

  3. SrF2 capsule design for heat engine applications

    International Nuclear Information System (INIS)

    Lester, D.H.

    1976-04-01

    A number of design changes were considered to improve heat transfer characteristics of the WESF capsule. This capsule was evaluated in a design concept for use as a heat source in a helium-working fluid, Stirling heat engine. Throughout the study a heat block concept was used. The helium was assumed to be at 1200 0 F and 200 atm. The upper temperature limit at the fuel-metal interface was assumed to be 800 0 C because of material compatibility considerations. A 0.6-in. thick outer can was considered since it may be required for impact resistance and high pressure accident environments. The modifications considered were: (1) filling all gaps with helium rather than air, (2) filling gaps with powdered metal, and (3) adding a third can to the existing capsule. Also, enhancement of emissivity on metal surfaces was considered as a possible modification

  4. Hybrid heat recovery - flat plate Stirling engine system

    International Nuclear Information System (INIS)

    Bogdanizh, A.M.; Budin, R.; Sutlovizh, I.

    2000-01-01

    In this paper, the possibility of process condensate heat recovery for boiler water preheating as well as for combined heat and power production for chosen process in textile industry has been investigated. The garment industry requires low pressure process steam or hot water for which production expensive fossil fuel should be used. Fuel usage can be reduced by various energy conservation methods. During the process a great quantity of hot condensate or waste hot water is rejected in the sewage system. To reduce heat wastes and improve technological process this condensate could be returned to the boiler for feed water preheating. When 60% condensate is returned to the steam generator about 8 % natural gas is saved. The rest of the condensate should be used for driving low temperature flat plate Stirling motor the advantage of the flat plate Stirling engine is ability to work at low temperatures. This engine produces electrical energy which can put in motion an electrogenerator in the same plant. While Stirling engine can be used electrical power and economical effect could be much greater using such a hybrid system the process waste heat is not only converted into useful work but at the same time thermal pollution is greatly diminished. (Author)

  5. Size dependence of efficiency at maximum power of heat engine

    KAUST Repository

    Izumida, Y.; Ito, N.

    2013-01-01

    We perform a molecular dynamics computer simulation of a heat engine model to study how the engine size difference affects its performance. Upon tactically increasing the size of the model anisotropically, we determine that there exists an optimum size at which the model attains the maximum power for the shortest working period. This optimum size locates between the ballistic heat transport region and the diffusive heat transport one. We also study the size dependence of the efficiency at the maximum power. Interestingly, we find that the efficiency at the maximum power around the optimum size attains a value that has been proposed as a universal upper bound, and it even begins to exceed the bound as the size further increases. We explain this behavior of the efficiency at maximum power by using a linear response theory for the heat engine operating under a finite working period, which naturally extends the low-dissipation Carnot cycle model [M. Esposito, R. Kawai, K. Lindenberg, C. Van den Broeck, Phys. Rev. Lett. 105, 150603 (2010)]. The theory also shows that the efficiency at the maximum power under an extreme condition may reach the Carnot efficiency in principle.© EDP Sciences Società Italiana di Fisica Springer-Verlag 2013.

  6. Size dependence of efficiency at maximum power of heat engine

    KAUST Repository

    Izumida, Y.

    2013-10-01

    We perform a molecular dynamics computer simulation of a heat engine model to study how the engine size difference affects its performance. Upon tactically increasing the size of the model anisotropically, we determine that there exists an optimum size at which the model attains the maximum power for the shortest working period. This optimum size locates between the ballistic heat transport region and the diffusive heat transport one. We also study the size dependence of the efficiency at the maximum power. Interestingly, we find that the efficiency at the maximum power around the optimum size attains a value that has been proposed as a universal upper bound, and it even begins to exceed the bound as the size further increases. We explain this behavior of the efficiency at maximum power by using a linear response theory for the heat engine operating under a finite working period, which naturally extends the low-dissipation Carnot cycle model [M. Esposito, R. Kawai, K. Lindenberg, C. Van den Broeck, Phys. Rev. Lett. 105, 150603 (2010)]. The theory also shows that the efficiency at the maximum power under an extreme condition may reach the Carnot efficiency in principle.© EDP Sciences Società Italiana di Fisica Springer-Verlag 2013.

  7. A novel heat engine for magnetizing superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, T A; Hong, Z; Zhu, X [Cambridge University Engineering Department, Trumpington Street, CB2 1PZ (United Kingdom); Krabbes, G [IFW Dresden, Helmholtzstrasse 20, 01069 Dresden (Germany)

    2008-03-01

    The potential of bulk melt-processed YBCO single domains to trap significant magnetic fields (Tomita and Murakami 2003 Nature 421 517-20; Fuchs et al 2000 Appl. Phys. Lett. 76 2107-9) at cryogenic temperatures makes them particularly attractive for a variety of engineering applications including superconducting magnets, magnetic bearings and motors (Coombs et al 1999 IEEE Trans. Appl. Supercond. 9 968-71; Coombs et al 2005 IEEE Trans. Appl. Supercond. 15 2312-5). It has already been shown that large fields can be obtained in single domain samples at 77 K. A range of possible applications exist in the design of high power density electric motors (Jiang et al 2006 Supercond. Sci. Technol. 19 1164-8). Before such devices can be created a major problem needs to be overcome. Even though all of these devices use a superconductor in the role of a permanent magnet and even though the superconductor can trap potentially huge magnetic fields (greater than 10 T) the problem is how to induce the magnetic fields. There are four possible known methods: (1) cooling in field; (2) zero field cooling, followed by slowly applied field; (3) pulse magnetization; (4) flux pumping. Any of these methods could be used to magnetize the superconductor and this may be done either in situ or ex situ. Ideally the superconductors are magnetized in situ. There are several reasons for this: first, if the superconductors should become demagnetized through (i) flux creep, (ii) repeatedly applied perpendicular fields (Vanderbemden et al 2007 Phys. Rev. B 75 (17)) or (iii) by loss of cooling then they may be re-magnetized without the need to disassemble the machine; secondly, there are difficulties with handling very strongly magnetized material at cryogenic temperatures when assembling the machine; thirdly, ex situ methods would require the machine to be assembled both cold and pre-magnetized and would offer significant design difficulties. Until room temperature superconductors can be prepared, the

  8. A novel heat engine for magnetizing superconductors

    International Nuclear Information System (INIS)

    Coombs, T A; Hong, Z; Zhu, X; Krabbes, G

    2008-01-01

    The potential of bulk melt-processed YBCO single domains to trap significant magnetic fields (Tomita and Murakami 2003 Nature 421 517-20; Fuchs et al 2000 Appl. Phys. Lett. 76 2107-9) at cryogenic temperatures makes them particularly attractive for a variety of engineering applications including superconducting magnets, magnetic bearings and motors (Coombs et al 1999 IEEE Trans. Appl. Supercond. 9 968-71; Coombs et al 2005 IEEE Trans. Appl. Supercond. 15 2312-5). It has already been shown that large fields can be obtained in single domain samples at 77 K. A range of possible applications exist in the design of high power density electric motors (Jiang et al 2006 Supercond. Sci. Technol. 19 1164-8). Before such devices can be created a major problem needs to be overcome. Even though all of these devices use a superconductor in the role of a permanent magnet and even though the superconductor can trap potentially huge magnetic fields (greater than 10 T) the problem is how to induce the magnetic fields. There are four possible known methods: (1) cooling in field; (2) zero field cooling, followed by slowly applied field; (3) pulse magnetization; (4) flux pumping. Any of these methods could be used to magnetize the superconductor and this may be done either in situ or ex situ. Ideally the superconductors are magnetized in situ. There are several reasons for this: first, if the superconductors should become demagnetized through (i) flux creep, (ii) repeatedly applied perpendicular fields (Vanderbemden et al 2007 Phys. Rev. B 75 (17)) or (iii) by loss of cooling then they may be re-magnetized without the need to disassemble the machine; secondly, there are difficulties with handling very strongly magnetized material at cryogenic temperatures when assembling the machine; thirdly, ex situ methods would require the machine to be assembled both cold and pre-magnetized and would offer significant design difficulties. Until room temperature superconductors can be prepared, the

  9. Irreversible performance of a quantum harmonic heat engine

    Science.gov (United States)

    Rezek, Yair; Kosloff, Ronnie

    2006-05-01

    The unavoidable irreversible loss of power in a heat engine is found to be of quantum origin. Following thermodynamic tradition, a model quantum heat engine operating in an Otto cycle is analysed, where the working medium is composed of an ensemble of harmonic oscillators and changes in volume correspond to changes in the curvature of the potential well. Equations of motion for quantum observables are derived for the complete cycle of operation. These observables are sufficient to determine the state of the system and with it all thermodynamical variables. Once the external controls are set, the engine settles to a limit cycle. Conditions for optimal work, power and entropy production are derived. At high temperatures and quasistatic operating conditions, the efficiency at maximum power coincides with the endoreversible result \\eta_q=1-\\sqrt{{T_c}/{T_h}} . The optimal compression ratio varies from {\\cal C} =\\sqrt{T_h/T_c} in the quasistatic limit where the irreversibility is dominated by heat conductance to {\\cal C} =(T_h/T_c)^{1/4} in the sudden limit when the irreversibility is dominated by friction. When the engine deviates from adiabatic conditions, the performance is subject to friction. The origin of this friction can be traced to the noncommutability of the kinetic and potential energy of the working medium.

  10. Fundamental Research in Engineering Education. Development of Concept Questions and Inquiry-Based Activities in Thermodynamics and Heat Transfer: An Example for Equilibrium vs. Steady-State

    Science.gov (United States)

    Vigeant, Margot; Prince, Michael; Nottis, Katharyn

    2011-01-01

    This study examines the use of inquiry-based instruction to promote the understanding of critical concepts in thermodynamics and heat transfer. Significant research shows that students frequently enter our courses with tightly held misconceptions about the physical world that are not effectively addressed through traditional instruction. Students'…

  11. Performance of discrete heat engines and heat pumps in finite time

    Science.gov (United States)

    Feldmann; Kosloff

    2000-05-01

    The performance in finite time of a discrete heat engine with internal friction is analyzed. The working fluid of the engine is composed of an ensemble of noninteracting two level systems. External work is applied by changing the external field and thus the internal energy levels. The friction induces a minimal cycle time. The power output of the engine is optimized with respect to time allocation between the contact time with the hot and cold baths as well as the adiabats. The engine's performance is also optimized with respect to the external fields. By reversing the cycle of operation a heat pump is constructed. The performance of the engine as a heat pump is also optimized. By varying the time allocation between the adiabats and the contact time with the reservoir a universal behavior can be identified. The optimal performance of the engine when the cold bath is approaching absolute zero is studied. It is found that the optimal cooling rate converges linearly to zero when the temperature approaches absolute zero.

  12. Thermoelectric properties of an interacting quantum dot based heat engine

    Science.gov (United States)

    Erdman, Paolo Andrea; Mazza, Francesco; Bosisio, Riccardo; Benenti, Giuliano; Fazio, Rosario; Taddei, Fabio

    2017-06-01

    We study the thermoelectric properties and heat-to-work conversion performance of an interacting, multilevel quantum dot (QD) weakly coupled to electronic reservoirs. We focus on the sequential tunneling regime. The dynamics of the charge in the QD is studied by means of master equations for the probabilities of occupation. From here we compute the charge and heat currents in the linear response regime. Assuming a generic multiterminal setup, and for low temperatures (quantum limit), we obtain analytical expressions for the transport coefficients which account for the interplay between interactions (charging energy) and level quantization. In the case of systems with two and three terminals we derive formulas for the power factor Q and the figure of merit Z T for a QD-based heat engine, identifying optimal working conditions which maximize output power and efficiency of heat-to-work conversion. Beyond the linear response we concentrate on the two-terminal setup. We first study the thermoelectric nonlinear coefficients assessing the consequences of large temperature and voltage biases, focusing on the breakdown of the Onsager reciprocal relation between thermopower and Peltier coefficient. We then investigate the conditions which optimize the performance of a heat engine, finding that in the quantum limit output power and efficiency at maximum power can almost be simultaneously maximized by choosing appropriate values of electrochemical potential and bias voltage. At last we study how energy level degeneracy can increase the output power.

  13. Prediction and Validation of Heat Release Direct Injection Diesel Engine Using Multi-Zone Model

    Science.gov (United States)

    Anang Nugroho, Bagus; Sugiarto, Bambang; Prawoto; Shalahuddin, Lukman

    2014-04-01

    The objective of this study is to develop simulation model which capable to predict heat release of diesel combustion accurately in efficient computation time. A multi-zone packet model has been applied to solve the combustion phenomena inside diesel cylinder. The model formulations are presented first and then the numerical results are validated on a single cylinder direct injection diesel engine at various engine speed and timing injections. The model were found to be promising to fulfill the objective above.

  14. Fuel savings with conventional hot water space heating systems by incorporating a natural gas powered heat pump. Preliminary project: Development of heat pump technology

    Science.gov (United States)

    Vanheyden, L.; Evertz, E.

    1980-12-01

    Compression type air/water heat pumps were developed for domestic heating systems rated at 20 to 150 kW. The heat pump is driven either by a reciprocating piston or rotary piston engine modified to operate on natural gas. Particular features of natural gas engines as prime movers, such as waste heat recovery and variable speed, are stressed. Two systems suitable for heat pump operation were selected from among five different mass produced car engines and were modified to incorporate reciprocating piston compressor pairs. The refrigerants used are R 12 and R 22. Test rig data transferred to field conditions show that the fuel consumption of conventional boilers can be reduced by 50% and more by the installation of engine driven heat pumps. Pilot heat pumps based on a 1,600 cc reciprocating piston engine were built for heating four two-family houses. Pilot pump operation confirms test rig findings. The service life of rotary piston and reciprocating piston engines was investigated. The tests reveal characteristic curves for reciprocating piston engines and include exhaust composition measurements.

  15. Performance evaluation and experiment system for waste heat recovery of diesel engine

    International Nuclear Information System (INIS)

    Wenzhi, Gao; Junmeng, Zhai; Guanghua, Li; Qiang, Bian; Liming, Feng

    2013-01-01

    In this paper, a waste heat recovery system is proposed where a high speed turbocharged diesel engine acts as the topper of a combined cycle with exhaust gases used for a bottoming Rankine cycle. The paper describes a mathematical model to evaluate the performance of Rankine cycle system with a reciprocating piston expander. The paper focuses on the performance evaluation and parameter selection of the heat exchanger and reciprocating piston expander that are suitable to waste heat recovery of ICE (internal combustion engine). The paper also describes the experimental setup and the preliminary results. The simulation results show that a proper intake pressure should be 4–5 MPa at its given mass flow rate of 0.015–0.021 kg/s depending on the waste heat recovery of a turbocharged diesel engine (80 kW/2590 rpm). The net power and net power rise rate at various ICE rotation speeds are calculated. The result shows that introducing heat recovery system can increase the engine power output by 12%, when diesel engine operates at 80 kW/2590 rpm. The preliminary experimental results indirectly prove the simulation model by two negative work loops in the P–V curve, under a low intake pressure and steam flow rate condition. - Highlights: • We investigate waste heat recovery through secondary fluid power cycle. • We establish a thermodynamic model of reciprocating steam engine. • We conduct the performance evaluation and experimental system development. • Primary parameters of the heat exchangers and expander are determined

  16. Modern thermodynamics from heat engines to dissipative structures

    CERN Document Server

    Kondepudi, Dilip

    2014-01-01

    Modern Thermodynamics: From Heat Engines to Dissipative Structures, Second Edition presents a comprehensive introduction to 20th century thermodynamics that can be applied to both equilibrium and non-equilibrium systems, unifying what was traditionally divided into 'thermodynamics' and 'kinetics' into one theory of irreversible processes. This comprehensive text, suitable for introductory as well as advanced courses on thermodynamics, has been widely used by chemists, physicists, engineers and geologists.  Fully revised and expanded, this new edition includes the following updates and featur

  17. Steam generators and waste heat boilers for process and plant engineers

    CERN Document Server

    Ganapathy, V

    2014-01-01

    Incorporates Worked-Out Real-World ProblemsSteam Generators and Waste Heat Boilers: For Process and Plant Engineers focuses on the thermal design and performance aspects of steam generators, HRSGs and fire tube, water tube waste heat boilers including air heaters, and condensing economizers. Over 120 real-life problems are fully worked out which will help plant engineers in evaluating new boilers or making modifications to existing boiler components without assistance from boiler suppliers. The book examines recent trends and developments in boiler design and technology and presents novel idea

  18. Recovery of Exhaust Waste Heat for ICE Using the Beta Type Stirling Engine

    OpenAIRE

    Aladayleh, Wail; Alahmer, Ali

    2015-01-01

    This paper investigates the potential of utilizing the exhaust waste heat using an integrated mechanical device with internal combustion engine for the automobiles to increase the fuel economy, the useful power, and the environment safety. One of the ways of utilizing waste heat is to use a Stirling engine. A Stirling engine requires only an external heat source as wasted heat for its operation. Because the exhaust gas temperature may reach 200 to 700°C, Stirling engine will work effectively....

  19. On introduction of artificial intelligence elements to heat power engineering

    Science.gov (United States)

    Dregalin, A. F.; Nazyrova, R. R.

    1993-10-01

    The basic problems of 'the thermodynamic intelligence' of personal computers have been outlined. The thermodynamic intellect of personal computers as a concept has been introduced to heat processes occurring in engines of flying vehicles. In particular, the thermodynamic intellect of computers is determined by the possibility of deriving formal relationships between thermodynamic functions. In chemical thermodynamics, a concept of a characteristic function has been introduced.

  20. Transforming Engineering Education - For Innovation and Development

    DEFF Research Database (Denmark)

    Marjoram, Tony

    2013-01-01

    Engineering and technology are of vital importance in innovation, social and economic development in higher and lower income countries. Development is driven by engineering applications and infrastructure, and most innovations derive from engineering. The last 50 years has seen significant change...... of young people in engineering, and the need to develop policy perspectives on the transformation of engineering education....... in knowledge production, dissemination and application, and associated needs for engineering, and yet engineering education has changed little over this period. This paper discusses the important role of problem-based learning and humanitarian engineering in promoting the interest, enrolment and retention...

  1. Numerical study on steam injection in a turbocompound diesel engine for waste heat recovery

    International Nuclear Information System (INIS)

    Zhao, Rongchao; Li, Weihua; Zhuge, Weilin; Zhang, Yangjun; Yin, Yong

    2017-01-01

    Highlights: • Steam injection was adopted in a turbocompound engine to further recover waste heat. • Thermodynamics model for the turbocompound engine was established and calibrated. • Steam injection at CT inlet obtained lower engine BSFC than injection at PT inlet. • The optimal injected steam mass at different engine speeds was presented. • Turbocompounding combined with steam injection can reduce the BSFC by 6.0–11.2%. - Abstract: Steam injection and turbocompouding are both effective methods for engine waste heat recovery. The fuel saving potential obtained by the combination of the two methods is not clear. Based on a turbocompound engine developed in the previous study, the impacts of pre-turbine steam injection on the fuel saving potentials of the turbocompound engine were investigated in this paper. Firstly, thermodynamic cycle model for the baseline turbocompound engine is established using commercial software GT-POWER. The cycle model is calibrated with the experiment data of the turbocompound engine and achieves high accuracy. After that, the influences of steam mass flow rate, evaporating pressure and injection location on the engine performance are studied. In addition, the impacts of hot liquid water injection are also investigated. The results show that steam injection at the turbocharger turbine inlet can reduce the turbocompound engine BSFC at all speed conditions. The largest fuel reduction 6.15% is obtained at 1000 rpm condition. However, steam injection at power turbine inlet can only lower the BSFC at high speed conditions. Besides, it is found that hot liquid water injection in the exhaust cannot improve the engine performance. When compared with the conventional turbocharged engine, the combination of turbocompounding and steam injection can reduce the BSFC by 6.0–11.2% over different speeds.

  2. Isobaric Expansion Engines: New Opportunities in Energy Conversion for Heat Engines, Pumps and Compressors

    Directory of Open Access Journals (Sweden)

    Maxim Glushenkov

    2018-01-01

    Full Text Available Isobaric expansion (IE engines are a very uncommon type of heat-to-mechanical-power converters, radically different from all well-known heat engines. Useful work is extracted during an isobaric expansion process, i.e., without a polytropic gas/vapour expansion accompanied by a pressure decrease typical of state-of-the-art piston engines, turbines, etc. This distinctive feature permits isobaric expansion machines to serve as very simple and inexpensive heat-driven pumps and compressors as well as heat-to-shaft-power converters with desired speed/torque. Commercial application of such machines, however, is scarce, mainly due to a low efficiency. This article aims to revive the long-known concept by proposing important modifications to make IE machines competitive and cost-effective alternatives to state-of-the-art heat conversion technologies. Experimental and theoretical results supporting the isobaric expansion technology are presented and promising potential applications, including emerging power generation methods, are discussed. It is shown that dense working fluids with high thermal expansion at high process temperature and low compressibility at low temperature make it possible to operate with reasonable thermal efficiencies at ultra-low heat source temperatures (70–100 °C. Regeneration/recuperation of heat can increase the efficiency notably and extend the area of application of these machines to higher heat source temperatures. For heat source temperatures of 200–600 °C, the efficiency of these machines can reach 20–50% thus making them a flexible, economical and energy efficient alternative to many today’s power generation technologies, first of all organic Rankine cycle (ORC.

  3. An assessment of CFD-based wall heat transfer models in piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Sircar, Arpan [Pennsylvania State Univ., University Park, PA (United States); Paul, Chandan [Pennsylvania State Univ., University Park, PA (United States); Ferreyro-Fernandez, Sebastian [Pennsylvania State Univ., University Park, PA (United States); Imren, Abdurrahman [Pennsylvania State Univ., University Park, PA (United States); Haworth, Daniel C [Pennsylvania State Univ., University Park, PA (United States)

    2017-04-26

    The lack of accurate submodels for in-cylinder heat transfer has been identified as a key shortcoming in developing truly predictive, physics-based computational fluid dynamics (CFD) models that can be used to develop combustion systems for advanced high-efficiency, low-emissions engines. Only recently have experimental methods become available that enable accurate near-wall measurements to enhance simulation capability via advancing models. Initial results show crank-angle dependent discrepancies with respect to previously used boundary-layer models of up to 100%. However, available experimental data is quite sparse (only few data points on engine walls) and limited (available measurements are those of heat flux only). Predictive submodels are needed for medium-resolution ("engineering") LES and for unsteady Reynolds-averaged simulations (URANS). Recently, some research groups have performed DNS studies on engine-relevant conditions using simple geometries. These provide very useful data for benchmarking wall heat transfer models under such conditions. Further, a number of new and more sophisticated models have also become available in the literature which account for these engine-like conditions. Some of these have been incorporated while others of a more complex nature, which include solving additional partial differential equations (PDEs) within the thin boundary layer near the wall, are underway. These models will then be tested against the available DNS/experimental data in both SI (spark-ignition) and CI (compression-ignition) engines.

  4. Method Engineering: Engineering of Information Systems Development Methods and Tools

    NARCIS (Netherlands)

    Brinkkemper, J.N.; Brinkkemper, Sjaak

    1996-01-01

    This paper proposes the term method engineering for the research field of the construction of information systems development methods and tools. Some research issues in method engineering are identified. One major research topic in method engineering is discussed in depth: situational methods, i.e.

  5. Method Engineering: Engineering of Information Systems Development Methods and Tools

    OpenAIRE

    Brinkkemper, J.N.; Brinkkemper, Sjaak

    1996-01-01

    This paper proposes the term method engineering for the research field of the construction of information systems development methods and tools. Some research issues in method engineering are identified. One major research topic in method engineering is discussed in depth: situational methods, i.e. the configuration of a project approach that is tuned to the project at hand. A language and support tool for the engineering of situational methods are discussed.

  6. Osmotic heat engine using thermally responsive ionic liquids

    KAUST Repository

    Zhong, Yujiang

    2017-07-11

    The osmotic heat engine (OHE) is a promising technology for converting low grade heat to electricity. Most of the existing studies have focused on thermolytic salt systems. Herein, for the first time, we proposed to use thermally responsive ionic liquids (TRIL) that have either an upper critical solution temperature (UCST) or lower critical solution temperature (LCST) type of phase behavior as novel thermolytic osmotic agents. Closed-loop TRIL-OHEs were designed based on these unique phase behaviors to convert low grade heat to work or electricity. Experimental studies using two UCST-type TRILs, protonated betaine bis(trifluoromethyl sulfonyl)imide ([Hbet][Tf2N]) and choline bis(trifluoromethylsulfonyl)imide ([Choline][Tf2N]) showed that (1) the specific energy of the TRIL-OHE system could reach as high as 4.0 times that of the seawater and river water system, (2) the power density measured from a commercial FO membrane reached up to 2.3 W/m2, and (3) the overall energy efficiency reached up to 2.6% or 18% of the Carnot efficiency at no heat recovery and up to 10.5% or 71% of the Carnet efficiency at 70% heat recovery. All of these results clearly demonstrated the great potential of using TRILs as novel osmotic agents to design high efficient OHEs for recovery of low grade thermal energy to work or electricity.

  7. Automotive Stirling Engine Development Program

    Science.gov (United States)

    Nightingale, N.; Ernst, W.; Richey, A.; Simetkosky, M.; Smith, G.; Antonelli, M. (Editor)

    1983-01-01

    Mod I engine testing and test results, the test of a Mod I engine in the United States, Mod I engine characterization and analysis, Mod I Transient Test Bed fuel economy, Mod I-A engine performance are discussed. Stirling engine reference engine manufacturing and reduced size studies, components and subsystems, and the study and test of low-cost casting alloys are also covered. The overall program philosophy is outlined, and data and results are presented.

  8. Engine and radiator: fetal and placental interactions for heat dissipation.

    Science.gov (United States)

    Schröder, H J; Power, G G

    1997-03-01

    The 'engine' of fetal metabolism generates heat (3-4 W kg-1 in fetal sheep) which has to be dissipated to the maternal organism. Fetal heat may move through the amniotic/allantoic fluids to the uterine wall (conductive pathway; total conductance, 1.1 W degrees C-1 kg-1) and with the umbilical arterial blood flow (convective pathway) to the placenta. Because resistance to heat flow is larger than zero fetal temperature exceeds maternal temperature by about 0.5 degree C (0.3-1 degree C). Probably 85% of fetal heat is lost to the maternal organism through the placenta, which thus serves as the main 'radiator'. Placental heat conductivity appears to be extremely high and this may lead to impaired heat exchange (guinea-pig placenta). A computer simulation demonstrates that fetal temperature is essentially clamped to maternal temperature, and that fetal thermoregulatory efforts to gain thermal independence would be futile. Indeed, when the late gestational fetus in utero is challenged by cold stress, direct and indirect indicators of (non-shivering) thermogenesis (oxygen consumption, increase of plasma glycerol and free fatty acid levels) change only moderately. In prematurely delivered lambs, however, cold stress provokes summit metabolism and maximum heat production. Only when birth is imitated in utero (by cord clamping, external artificial lung ventilation and cooling) do thermogenic efforts approach levels typical of extra-uterine life. This suggests the presence of inhibitors of thermogenesis of placental origin, e.g. prostaglandins and adenosine. When the synthesis of prostaglandins is blocked by pretreatment with indomethacin, sheep fetuses react to intra-uterine cooling with vigorous thermogenic responses, which can be subdued by infusion of prostaglandin E2 (PGE2). Since the sheep placenta is known to produce sufficient amounts of PGE2, it seems that the placenta controls fetal thermogenic responses to some extent. This transforms the fetus into an ectothermic

  9. 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.

  10. Sliding seal materials for low heat rejection engines

    Science.gov (United States)

    Beaty, Kevin; Lankford, James; Vinyard, Shannon

    1989-01-01

    Sliding friction coefficients and wear rates of promising piston seal materials were measured under temperature, environmental, velocity, and loading conditions that are representative of the low heat rejection (LHR) diesel engine environment. These materials included carbides, oxides, and nitrides. In addition, silicon nitride and partially stablized zirconia disks (cylinder liners) were ion-implanted with TiNi, Ni, Co, and Cr, and subsequently run against carbide pins (piston rings), with the objective of producing reduced friction via solid lubrication at elevated temperature. Friction and wear measurements were obtained using pin-on-disk laboratory experiments and a unique engine friction test rig. Unmodified ceramic sliding couples were characterized at all temperatures by friction coefficients of 0.24 and above during the pin-on-disk tests. The coefficient at 800 C in an oxidizing environment was reduced to below 0.1, for certain material combination, by the ion-implantation of TiNi or Co. This beneficial effect was found to derive from the lubricious Ti, Ni, and Co oxides. Similar results were demonstrated on the engine friction test rig at lower temperatures. The structural integrity and feasibility of engine application with the most promising material combination were demonstrated during a 30-hour single-cylinder, direct-injection diesel engine test.

  11. The development of a solar residential heating and cooling system

    Science.gov (United States)

    1975-01-01

    The MSFC solar heating and cooling facility was assembled to demonstrate the engineering feasibility of utilizing solar energy for heating and cooling buildings, to provide an engineering evaluation of the total system and the key subsystems, and to investigate areas of possible improvement in design and efficiency. The basic solar heating and cooling system utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating, and an absorption cycle air conditioner for space cooling. A complete description of all systems is given. Development activities for this test system included assembly, checkout, operation, modification, and data analysis, all of which are discussed. Selected data analyses for the first 15 weeks of testing are included, findings associated with energy storage and the energy storage system are outlined, and conclusions resulting from test findings are provided. An evaluation of the data for summer operation indicates that the current system is capable of supplying an average of 50 percent of the thermal energy required to drive the air conditioner. Preliminary evaluation of data collected for operation in the heating mode during the winter indicates that nearly 100 percent of the thermal energy required for heating can be supplied by the system.

  12. A comparative study of open and closed heat-engines for small-scale CHP applications

    OpenAIRE

    Eames, Ian W.; Evans, Kieran; Pickering, Stephen

    2016-01-01

    In this paper the authors compare and contrast open and closed-cycle heat engines. First of all, by way of example and to aid discussion, the performance of proprietary externally heated closed-cycle Stirling engines is compared with that of internally heated open Otto cycle engines. Both types of engine have disadvantages and merits and this suggested that in order to accommodate the best of both engine types an externally-heated open-cycle engine might offer a more satisfactory solution for...

  13. Energy distributions in a diesel engine using low heat rejection (LHR) concepts

    International Nuclear Information System (INIS)

    Li, Tingting; Caton, Jerald A.; Jacobs, Timothy J.

    2016-01-01

    Highlights: • Altering coolant temperature was employed to devise low heat rejection concept. • The energy distributions at different engine coolant temperatures were analyzed. • Raising coolant temperature yields improvements in fuel conversion efficiency. • The exhaust energy is highly sensitive to the variations in exhaust temperature. • Effects of coolant temperature on mechanical efficiency were examined. - Abstract: The energy balance analysis is recognized as a useful method for aiding the characterization of the performance and efficiency of internal combustion (IC) engines. Approximately one-third of the total fuel energy is converted to useful work in a conventional IC engine, whereas the major part of the energy input is rejected to the exhaust gas and the cooling system. The idea of a low heat rejection (LHR) engine (also called “adiabatic engine”) was extensively developed in the 1980s due to its potential in improving engine thermal efficiency via reducing the heat losses. In this study, the LHR operating condition is implemented by increasing the engine coolant temperature (ECT). Experimentally, the engine is overcooled to low ECTs and then increased to 100 °C in an effort to get trend-wise behavior without exceeding safe ECTs. The study then uses an engine simulation of the conventional multi-cylinder, four-stroke, 1.9 L diesel engine operating at 1500 rpm to examine the five cases having different ECTs. A comparison between experimental and simulation results show the effects of ECT on fuel conversion efficiency. The results demonstrate that increasing ECT yields slight improvements in net indicated fuel conversion efficiency, with larger improvements observed in brake fuel conversion efficiency.

  14. An experimental study of the enhanced heating capacity of an electric heat pump (EHP) using the heat recovered from a gas engine generator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Cheol Min; Chang, Se Dong [HAC R and D Laboratory, LG Electronics, 327-23 Gasan-Dong, Geumcheon-gu, Seoul 153-802 (Korea); Lee, Jaekeun; Hwang, Yujin [School of Mechanical Engineering, Pusan National University, San 30, Changjeon-Dong, Keumjeong-Ku, Busan 609-735 (Korea)

    2009-11-15

    This paper is concerned with the effect of recovered heat on the heating capacity of an Electric Heat Pump (EHP), which is supplied with electric power and recovered heat from a gas engine generator system. Two methods of supplying recovery heat are examined: (i) to the refrigerant with the discharge line heat exchanger (HEX), and (ii) to the refrigerant of the evaporator with the sub-evaporator. Heating capacity, input power and coefficient of performance (COP) were investigated and compared for each heat recovery method. Conclusively, we found that the second method was most reasonable to recover wasted heat and increased system COP by 215%. (author)

  15. Parametric study of power turbine for diesel engine waste heat recovery

    International Nuclear Information System (INIS)

    Zhao, Rongchao; Zhuge, Weilin; Zhang, Yangjun; Yin, Yong; Chen, Zhen; Li, Zhigang

    2014-01-01

    Turbocompounding is a promising technology to recover waste heat from the exhaust and reduce fuel consumption for internal combustion engine. The design of a power turbine plays a key role in turbocompound engine performance. This paper presents a set of parametric studies of power turbine performed on a turbocompound diesel engine by means of turbine through-flow model developed by the authors. This simulation model was verified and validated using engine performance test data and achieved reasonable accuracy. The paper first analyzed the influence of three key geometrical parameters (blade height, blade radius and nozzle exit blade angle) on turbine expansion ratio and engine fuel consumptions. After that, the impacts of the geometrical parameters on power distribution, air mass flow rate and exhaust temperature were analyzed. Results showed that these parameters had significant effects on engine BSFC and power. At high engine speeds, there existed an optimum value of geometry parameter to obtain the lowest BSFC. At low engine speeds, the engine BSFC kept increasing or decreasing continuously as the geometry parameters changed. Research also found that the engine BSFC was most sensitive to the nozzle exit blade angle, which should be considered carefully during the design process. This paper provides a useful method for matching and designing of a power turbine for turbocompound engine. - Highlights: •Through-flow model of axial-flow power turbine for turbocompound engine was established. •Turbocompound engine performance test was carried out to validate the cycle simulation model. •Influences of power turbine geometry parameters on engine BSFC and power were presented

  16. Systems Engineering Leadership Development: Advancing Systems Engineering Excellence

    Science.gov (United States)

    Hall, Phil; Whitfield, Susan

    2011-01-01

    This slide presentation reviews the Systems Engineering Leadership Development Program, with particular emphasis on the work being done in the development of systems engineers at Marshall Space Flight Center. There exists a lack of individuals with systems engineering expertise, in particular those with strong leadership capabilities, to meet the needs of the Agency's exploration agenda. Therefore there is a emphasis on developing these programs to identify and train systems engineers. The presentation reviews the proposed MSFC program that includes course work, and developmental assignments. The formal developmental programs at the other centers are briefly reviewed, including the Point of Contact (POC)

  17. Heat exchanger modeling and identification for control of waste heat recovery systems in diesel engines

    NARCIS (Netherlands)

    Feru, E.; Willems, F.P.T.; Rojer, C.; Jager, B. de; Steinbuch, M.

    2013-01-01

    To meet future CO2 emission targets, Waste Heat Recovery systems have recently attracted much attention for automotive applications, especially for long haul trucks. This paper focuses on the development of a dynamic counter-flow heat exchanger model for control purposes. The model captures the

  18. Development of an engine system simulation software package - ESIM

    Energy Technology Data Exchange (ETDEWEB)

    Erlandsson, Olof

    2000-10-01

    A software package, ESIM is developed for simulating internal combustion engine systems, including models for engine, manifolds, turbocharger, charge-air cooler (inter cooler) and inlet air heater. This study focus on the thermodynamic treatment and methods used in the models. It also includes some examples of system simulations made with these models for validation purposes. The engine model can be classified as a zero-dimensional, single zone model. It includes calculation of the valve flow process, models for heat release and models for in-cylinder, exhaust port and manifold heat transfer. Models are developed for handling turbocharger performance and charge air cooler characteristics. The main purpose of the project related to this work is to use the ESIM software to study heat balance and performance of homogeneous charge compression ignition (HCCI) engine systems. A short description of the HCCI engine is therefore included, pointing out the difficulties, or challenges regarding the HCCI engine, from a system perspective. However, the relations given here, and the code itself, is quite general, making it possible to use these models to simulate spark ignited, as well as direct injected engines.

  19. Perspectives of ukrainian mechanical engineering development

    OpenAIRE

    Dyrda, E.; Schepetkova, A.; Galushko, O.

    2013-01-01

    Theses are devoted to problems and perspectives of Ukrainian mechanical engineering development. Role of mechanical engineering in national economy is described. Problems of mechanical engineering, such as losing the cometetive advantages, production decreasing, debts growing, ineffective assets structure, are investigated. Influence of European integration process on mechanical engineering enterprises is discussed.

  20. Career Development in Nuclear Engineering

    International Nuclear Information System (INIS)

    Sibbens, G.

    2015-01-01

    In the eighties it was not common for girls to study engineering. But a few young girls have always been fascinated by science and technical applications and dared to go for a gender untypical education. What are these female engineers doing today? This paper describes the career development of a woman, who completed her Master of Science in Nuclear Engineering, found first a job in an international company as cooperator in the research group of radiation physics and later as head of technical support and quality assurance of medical systems and then succeeded in a competition to be recruited at the European Commission (EC). There she started as an assistant for the primary standardisation of radionuclides and high-resolution alpha-particle spectrometry including the preparation of radioactive sources in the radionuclide metrology sector at the Institute for Reference Materials and Measurements of the European Commission’s Joint Research Centre and consequently published her work in scientific journals. Today, 29 years later, I am the laboratory responsible for the preparation and characterisation of nuclear targets at EC-JRC-IRMM, leading a team that has unique know-how in the preparation of thin film deposits (called targets) tailor-made for nuclear physics measurements at the EC–JRC–IRMM and international accelerator sites. High quality measurements of nuclear data and materials are being asked for in the context of nuclear safety, minimisation of high level nuclear waste and safeguards and security. The different steps of my career development and the repeated process of managing learning, work, family and leisure are presented. The career path across different jobs and responsibilities and the career progress via a certification training programme are also explained to encourage the next generation of female professionals to continue playing a vital role in nuclear science and technology. (author)

  1. Applicability of advanced automotive heat engines to solar thermal power

    Science.gov (United States)

    Beremand, D. G.; Evans, D. G.; Alger, D. L.

    The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

  2. Convective Heating of the LIFE Engine Target During Injection

    Energy Technology Data Exchange (ETDEWEB)

    Holdener, D S; Tillack, M S; Wang, X R

    2011-10-24

    Target survival in the hostile, high temperature xenon environment of the proposed Laser Inertial Fusion Energy (LIFE) engine is critical. This work focuses on the flow properties and convective heat load imposed upon the surface of the indirect drive target while traveling through the xenon gas. While this rarefied flow is traditionally characterized as being within the continuum regime, it is approaching transition where conventional CFD codes reach their bounds of operation. Thus ANSYS, specifically the Navier-Stokes module CFX, will be used in parallel with direct simulation Monte Carlo code DS2V and analytically and empirically derived expressions for heat transfer to the hohlraum for validation. Comparison of the viscous and thermal boundary layers of ANSYS and DS2V were shown to be nearly identical, with the surface heat flux varying less than 8% on average. From the results herein, external baffles have been shown to reduce this heat transfer to the sensitive laser entrance hole (LEH) windows and optimize target survival independent of other reactor parameters.

  3. The relative effects of fuel concentration, residual-gas fraction, gas motion, spark energy and heat losses to the electrodes on flame-kernel development in a lean-burn spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Aleiferis, P.G.; Taylor, A.M.K.P. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Dept. of Mechanical Engineering; Ishii, K. [Honda International Technical School, Saitama (Japan); Urata, Y. [Honda R and D Co., Ltd., Tochigi (Japan). Tochigi R and D Centre

    2004-04-01

    The potential of lean combustion for the reduction in exhaust emissions and fuel consumption in spark ignition engines has long been established. However, the operating range of lean-burn spark ignition engines is limited by the level of cyclic variability in the early-flame development stage that typically corresponds to the 0-5 per cent mass fraction burned duration. In the current study, the cyclic variations in early flame development were investigated in an optical stratified-charge spark ignition engine at conditions close to stoichiometry [air-to-fuel ratio (A/F) = 15] and to the lean limit of stable operation (A/F = 22). Flame images were acquired through either a pentroof window ('tumble plane' of view) or the piston crown ('swirl plane' of view) and these were processed to calculate the intra-cycle flame-kernel radius evolution. In order to quantify the relative effects of local fuel concentration, gas motion, spark-energy release and heat losses to the electrodes on the flame-kernel growth rate, a zero-dimensional flame-kernel growth model, in conjunction with a one-dimensional spark ignition model, was employed. Comparison of the calculated flame-radius evolutions with the experimental data suggested that a variation in A/F around the spark plug of {delta}(A/F) {approx} 4 or, in terms of equivalence ratio {phi}, a variation in {delta}{phi} {approx} 0.15 at most was large enough to account for 100 per cent of the observed cyclic variability in flame-kernel radius. A variation in the residual-gas fraction of about 20 per cent around the mean was found to account for up to 30 per cent of the variability in flame-kernel radius at the timing of 5 per cent mass fraction burned. The individual effect of 20 per cent variations in the 'mean' in-cylinder velocity at the spark plug at ignition timing was found to account for no more than 20 per cent of the measured cyclic variability in flame kernel radius. An individual effect of

  4. Engineering Scoping Study of Thermoelectric Generator Systems for Industrial Waste Heat Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, Terry [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Choate, William T. [BCS, Inc., Laurel, MD (United States)

    2006-11-01

    This report evaluates thermoelectric generator (TEG) systems with the intent to: 1) examine industrial processes in order to identify and quantify industrial waste heat sources that could potentially use TEGs; 2) describe the operating environment that a TEG would encounter in selected industrial processes and quantify the anticipated TEG system performance; 3) identify cost, design and/or engineering performance requirements that will be needed for TEGs to operate in the selected industrial processes; and 4) identify the research, development and deployment needed to overcome the limitations that discourage the development and use of TEGs for recovery of industrial waste heat.

  5. Heat transfer modeling in exhaust systems of high-performance two-stroke engines

    OpenAIRE

    Lujan Martinez, José Manuel; Climent Puchades, Héctor; Olmeda González, Pablo Cesar; JIMENEZ MACEDO, VICTOR DANIEL

    2014-01-01

    Heat transfer from the hot gases to the wall in exhaust systems of high-performance two-stroke engines is underestimated using steady state with fully developed flow empirical correlations. This fact is detected when comparing measured and modeled pressure pulses in different positions in the exhaust system. This can be explained taking into account that classical expressions have been validated for fully developed flows, a situation that is far from the flow behavior in reciprocating interna...

  6. 3 kW Stirling engine for power and heat production

    DEFF Research Database (Denmark)

    Thorsen, Jan Eric; Bovin, Jonas Kabell; Carlsen, Henrik

    1996-01-01

    A new 3 kW Beta-type Stirling engine has been developed. The engine uses natural gas as fuel and is designed for use as a small combined heat and power plant for single family houses. The electrical power is supplied to the grid. The engine is made as a hermetic device, where the crank mechanism...... and the alternator are built into a pressurized crank casing. The engine produces 3 kW of shaft power corresponding to 2.4 kW of electric power. The heat input is 10 kW representing a shaft efficiency of 30% and an electric efficiency of 24%. Helium at 8 MPa mean pressure is used as the working gas. The crank...... for X-heads. A grease-lubricated needle and ball bearings are used in the kinematic crank mechanism. The burner includes an air preheater and a water jacket which makes it possible to utilize nearly all of the heat from the combustion gases. The performance of the engine has been tested as a function...

  7. Development of a Thermoacoustic Stirling Engine Technology Demonstrator

    Science.gov (United States)

    Reissner, Alexander; Gerger, Joachim; Hummel, Stefan; Reißig, Jannis; Pawelke, Roland

    2014-08-01

    Waste heat is a primary source of energy loss in many aerospace and terrestrial applications. FOTEC, an Austrian Research Company located in Wiener Neustadt, is presently developing a micro power converter, promising high efficiencies even for small- scale applications. The converter is based on an innovative thermoacoustic stirling engine concept without any moving parts. Such a maintenance-free engine system would be particularly suitable for advanced space power systems (radioisotope, waste heat) or even within the scope of terrestrial energy harvesting. This paper will summarizes the status of our ongoing efforts on this micro power converter technology.

  8. Developing the use of renewable heat

    International Nuclear Information System (INIS)

    Nifenecker, Herve

    2013-01-01

    The author reports a study in which he shows that the heat production by means of renewable energies is an efficient method to reach the objective of 23 per cent of renewable energies in the French final energy consumption. He browses the different techniques of renewable heat production (solar heat, wood-fuel, surface geothermal) and indicates the associated potential resources. He proposes a cost analysis which compares the use of gas and electricity with three techniques of production of renewable heat: solar heat to produce hot water, biomass combustion (more particularly wood), solar heat extracted with fuel cells. He also assesses tariffs and CO 2 emissions. Then, he elaborates a strategy to phase out fossil energies: a modification of the RT 2012 thermal regulation, to give up the purchase obligation for electricity produced by wind and photovoltaic energy, to extend the CSPE calculation basis, to put oil-fuel and gas boilers out of the market, to support the development of renewable heat production, to improve the competitiveness of the different techniques of renewable heat production. He finally gives a brief overview of industrial perspectives created by such a development of renewable heat

  9. Development of an Engineering Soil Database

    Science.gov (United States)

    2017-12-27

    ER D C TR 1 7- 15 Rapid Airfield Damage Recovery (RADR) Program Development of an Engineering Soil Database En gi ne er R es ea rc...distribution is unlimited. The US Army Engineer Research and Development Center (ERDC) solves the nation’s toughest engineering and environmental...challenges. ERDC develops innovative solutions in civil and military engineering , geospatial sciences, water resources, and environmental sciences

  10. Ecological optimization of an irreversible quantum Carnot heat engine with spin-1/2 systems

    International Nuclear Information System (INIS)

    Liu Xiaowei; Chen Lingen; Wu Feng; Sun Fengrui

    2010-01-01

    A model of a quantum heat engine with heat resistance, internal irreversibility and heat leakage and many non-interacting spin-1/2 systems is established in this paper. The quantum heat engine cycle is composed of two isothermal processes and two irreversible adiabatic processes and is referred to as a spin quantum Carnot heat engine. Based on the quantum master equation and the semi-group approach, equations of some important performance parameters, such as power output, efficiency, entropy generation rate and ecological function (a criterion representing the optimal compromise between exergy output rate and exergy loss rate), for the irreversible spin quantum Carnot heat engine are derived. The optimal ecological performance of the heat engine in the classical limit is analyzed with numerical examples. The effects of internal irreversibility and heat leakage on ecological performance are discussed in detail.

  11. Comparison of Engine Simulation Software for Development of Control System

    Directory of Open Access Journals (Sweden)

    KinYip Chan

    2013-01-01

    Full Text Available Most commonly used commercial engine simulation packages generate detailed estimation of the combustion and gas flow parameters. These parameters are required for advanced research on fluid flow and heat transfer and development of geometries of engine components. However, engine control involves different operating parameters. Various sensors are installed into the engine, the combustion performance is recorded, and data is sent to engine control unit (ECU. ECU computes the new set of parameters to make fine adjustments to actuators providing better engine performance. Such techniques include variable valve timing, variable ignition timing, variable air to fuel ratio, and variable compression ratio. In the present study, two of the commercial packages, Ricardo Wave and Lotus Engine Simulation, have been tested on the capabilities for engine control purposes. These packages are compared with an in-house developed package and with reference results available from the literature. Different numerical experiments have been carried out from which it can be concluded that all packages predict similar profiles of pressure and temperature in the engine cylinder. Moreover, those are in reasonable agreement with the reference results while in-house developed package is possible to run simulations with changing speed for engine control purpose.

  12. Many-objective thermodynamic optimization of Stirling heat engine

    International Nuclear Information System (INIS)

    Patel, Vivek; Savsani, Vimal; Mudgal, Anurag

    2017-01-01

    This paper presents a rigorous investigation of many-objective (four-objective) thermodynamic optimization of a Stirling heat engine. Many-objective optimization problem is formed by considering maximization of thermal efficiency, power output, ecological function and exergy efficiency. Multi-objective heat transfer search (MOHTS) algorithm is proposed and applied to obtain a set of Pareto-optimal points. Many objective optimization results form a solution in a four dimensional hyper objective space and for visualization it is represented on a two dimension objective space. Thus, results of four-objective optimization are represented by six Pareto fronts in two dimension objective space. These six Pareto fronts are compared with their corresponding two-objective Pareto fronts. Quantitative assessment of the obtained Pareto solutions is reported in terms of spread and the spacing measures. Different decision making approaches such as LINMAP, TOPSIS and fuzzy are used to select a final optimal solution from Pareto optimal set of many-objective optimization. Finally, to reveal the level of conflict between these objectives, distribution of each decision variable in their allowable range is also shown in two dimensional objective spaces. - Highlights: • Many-objective (i.e. four objective) optimization of Stirling engine is investigated. • MOHTS algorithm is introduced and applied to obtain a set of Pareto points. • Comparative results of many-objective and multi-objectives are presented. • Relationship of design variables in many-objective optimization are obtained. • Optimum solution is selected by using decision making approaches.

  13. Multilevel quantum Otto heat engines with identical particles

    Science.gov (United States)

    Huang, X. L.; Guo, D. Y.; Wu, S. L.; Yi, X. X.

    2018-02-01

    A quantum Otto heat engine is studied with multilevel identical particles trapped in one-dimensional box potential as working substance. The symmetrical wave function for Bosons and the anti-symmetrical wave function for Fermions are considered. In two-particle case, we focus on the ratios of W^i (i=B,F) to W_s, where W^B and W^F are the work done by two Bosons and Fermions, respectively, and W_s is the work output of a single particle under the same conditions. Due to the symmetrical of the wave functions, the ratios are not equal to 2. Three different regimes, low-temperature regime, high-temperature regime, and intermediate-temperature regime, are analyzed, and the effects of energy level number and the differences between the two baths are calculated. In the multiparticle case, we calculate the ratios of W^i_M/M to W_s, where W^i_M/M can be seen as the average work done by a single particle in multiparticle heat engine. For other working substances whose energy spectrum has the form of E_n˜ n^2, the results are similar. For the case E_n˜ n, two different conclusions are obtained.

  14. Recovery of Exhaust Waste Heat for ICE Using the Beta Type Stirling Engine

    Directory of Open Access Journals (Sweden)

    Wail Aladayleh

    2015-01-01

    Full Text Available This paper investigates the potential of utilizing the exhaust waste heat using an integrated mechanical device with internal combustion engine for the automobiles to increase the fuel economy, the useful power, and the environment safety. One of the ways of utilizing waste heat is to use a Stirling engine. A Stirling engine requires only an external heat source as wasted heat for its operation. Because the exhaust gas temperature may reach 200 to 700°C, Stirling engine will work effectively. The indication work, real shaft power and specific fuel consumption for Stirling engine, and the exhaust power losses for IC engine are calculated. The study shows the availability and possibility of recovery of the waste heat from internal combustion engine using Stirling engine.

  15. Engineering development testing of the GPHS-RTG converter

    International Nuclear Information System (INIS)

    Cockfield, R.D.

    1981-01-01

    The GPHS-RTG will provide electrical power for the Galileo orbiter and for the two spacecraft of the International Solar Polar Mission. The GPHS-RTG consists of two primary assemblies: the General Purpose Heat Source, and the converter. This paper deals only with the converter, and highlights engineering tests that provide support for its design development

  16. 9 CFR 91.22 - Protection from heat of boilers and engines.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Protection from heat of boilers and... Protection from heat of boilers and engines. No animals shall be stowed along the alleyways leading to the engine or boiler rooms unless the sides of said engine or boiler rooms are covered by a tongue and groove...

  17. Educating Civil Engineers for Developing Countries

    Science.gov (United States)

    Stanley, D.

    1974-01-01

    Based on engineering teaching experience in Africa and Asia, ideas are presented on educating civil engineers for developing countries, especially those in Africa. Some of the problems facing educational planners, teachers, and students are addressed, including responsibilities of a newly graduated civil engineer, curriculum development, and…

  18. The atmospheric heat engine response to climate change

    Science.gov (United States)

    Pauluis, O. M.

    2014-12-01

    Moist convection is characterized by complex interactions between dynamics and thermodynamics. As air parcels within the atmosphere, they experience multiple thermodynamic transformations, such as compression and expansion, diabatic heating and cooling, condensation and mixing. These transformations correspond to those of a heat engine that produces kinetic energy while transporting energy from a warm source to a colder sink. This atmospheric heat engine is however directly affected by moist processes. First, falling precipitation acts as a break on the circulation by dissipating a significant amount of kinetic energy. Second, evaporation of unsaturated water and diffusion of water vapor are irrevesible processes that also reduce the amount of work that can be produced. An important challenge is to quantify the impacts that these two effects have on the generation of kinetic energy. Here, I will introduce a new technique - the Mean Air Flow As Lagragian Dynamics Approximation (MAFALDA) - that can be used to systematically analyze the thermodynamic behavior of complex atmospheric flows. This approach relies on sorting the upward mass transport in terms of the equivalent potential temperature of the air parcels to obtain an isentropic streamfunction. This streamfunction is then used to determine the thermodynamic evolution of air parcels as they move through the atmosphere. This approach is applied to analyze how convective systems would behave in a warmer climate. It is shown that an increase in atmospheric temperature lead to a significant increase of the amount of kinetic energy that is produced per unit of mass of air transported. At the same time, the total generation of kinetic energy is only slightly affected. Taken together, these findings imply that, in a warming atmosphere, the number of intense convective events will be reduced, while their intensity should increase. I will also discuss the new possibility of systematically studying the thermodynamic

  19. Performance Analysis and Optimization of a Solar Powered Stirling Engine with Heat Transfer Considerations

    Directory of Open Access Journals (Sweden)

    Chia-En Ho

    2012-09-01

    Full Text Available This paper investigates the optimization of the performance of a solar powered Stirling engine based on finite-time thermodynamics. Heat transference in the heat exchangers between a concentrating solar collector and the Stirling engine is studied. The irreversibility of a Stirling engine is considered with the heat transfer following Newton's law. The power generated by a Stirling engine is used as an objective function for maximum power output design with the concentrating solar collector temperature and the engine thermal efficiency as the optimization parameters. The maximum output power of engine and its corresponding system parameters are determined using a genetic algorithm.

  20. Development of Engine Loads Methodology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR seeks to improve the definition of design loads for rocket engine components such that higher performing, lighter weight engines can be developed more...

  1. Campaign Quality Gap: Developing Strategic Engineering Competency

    National Research Council Canada - National Science Library

    Wilson, Jr, Roger A

    2007-01-01

    Recent policy developments in the Department of Defense (DOD) impose new and significant challenges for the Nation's strategic engineering directorate, the US Army Corps of Engineers (USACE). DOD Directive...

  2. Effect of translucence of engineering ceramics on heat transfer in diesel engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wahiduzzaman, S.; Morel, T. [Integral Technologies, Inc., Westmont, IL (United States)

    1992-04-01

    This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

  3. Effect of translucence of engineering ceramics on heat transfer in diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Wahiduzzaman, S.; Morel, T. (Integral Technologies, Inc., Westmont, IL (United States))

    1992-04-01

    This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

  4. Biogas Engine Waste Heat Recovery Using Organic Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Alberto Benato

    2017-03-01

    Full Text Available Italy is a leading country in the biogas sector. Energy crops and manure are converted into biogas using anaerobic digestion and, then, into electricity using internal combustion engines (ICEs. Therefore, there is an urgent need for improving the efficiency of these engines taking the real operation into account. To this purpose, in the present work, the organic Rankine cycle (ORC technology is used to recover the waste heat contained in the exhaust gases of a 1 MWel biogas engine. The ICE behavior being affected by the biogas characteristics, the ORC unit is designed, firstly, using the ICE nameplate data and, then, with data measured during a one-year monitoring activity. The optimum fluid and the plant configuration are selected in both cases using an “in-house” optimization tool. The optimization goal is the maximization of the net electric power while the working fluid is selected among 115 pure fluids and their mixtures. Results show that a recuperative ORC designed using real data guarantees a 30% higher net electric power than the one designed with ICE nameplate conditions.

  5. Software engineering architecture-driven software development

    CERN Document Server

    Schmidt, Richard F

    2013-01-01

    Software Engineering: Architecture-driven Software Development is the first comprehensive guide to the underlying skills embodied in the IEEE's Software Engineering Body of Knowledge (SWEBOK) standard. Standards expert Richard Schmidt explains the traditional software engineering practices recognized for developing projects for government or corporate systems. Software engineering education often lacks standardization, with many institutions focusing on implementation rather than design as it impacts product architecture. Many graduates join the workforce with incomplete skil

  6. Cryogenic rocket engine development at Delft aerospace rocket engineering

    NARCIS (Netherlands)

    Wink, J; Hermsen, R.; Huijsman, R; Akkermans, C.; Denies, L.; Barreiro, F.; Schutte, A.; Cervone, A.; Zandbergen, B.T.C.

    2016-01-01

    This paper describes the current developments regarding cryogenic rocket engine technology at Delft Aerospace Rocket Engineering (DARE). DARE is a student society based at Delft University of Technology with the goal of being the first student group in the world to launch a rocket into space. After

  7. The development and application of CFD technology in mechanical engineering

    Science.gov (United States)

    Wei, Yufeng

    2017-12-01

    Computational Fluid Dynamics (CFD) is an analysis of the physical phenomena involved in fluid flow and heat conduction by computer numerical calculation and graphical display. The numerical method simulates the complexity of the physical problem and the precision of the numerical solution, which is directly related to the hardware speed of the computer and the hardware such as memory. With the continuous improvement of computer performance and CFD technology, it has been widely applied to the field of water conservancy engineering, environmental engineering and industrial engineering. This paper summarizes the development process of CFD, the theoretical basis, the governing equations of fluid mechanics, and introduces the various methods of numerical calculation and the related development of CFD technology. Finally, CFD technology in the mechanical engineering related applications are summarized. It is hoped that this review will help researchers in the field of mechanical engineering.

  8. HEAT TRANSFER IN EXHAUST SYSTEM OF A COLD START ENGINE AT LOW ENVIRONMENTAL TEMPERATURE

    Directory of Open Access Journals (Sweden)

    Snežana D Petković

    2010-01-01

    Full Text Available During the engine cold start, there is a significantly increased emission of harmful engine exhaust gases, particularly at very low environmental temperatures. Therefore, reducing of emission during that period is of great importance for the reduction of entire engine emission. This study was conducted to test the activating speed of the catalyst at low environmental temperatures. The research was conducted by use of mathematical model and developed computer programme for calculation of non-stationary heat transfer in engine exhaust system. During the research, some of constructional parameters of exhaust system were adopted and optimized at environmental temperature of 22 C. The combination of design parameters giving best results at low environmental temperatures was observed. The results showed that the temperature in the environment did not have any significant influence on pre-catalyst light-off time.

  9. Efficiencies and coefficients of performance of heat engines, refrigerators, and heat pumps with friction: a universal limiting behavior.

    Science.gov (United States)

    Bizarro, João P S; Rodrigues, Paulo

    2012-11-01

    For work-producing heat engines, or work-consuming refrigerators and heat pumps, the percentage decrease caused by friction in their efficiencies, or coefficients of performance (COP's), is approximately given by the ratio W(fric)/W between the work spent against friction forces and the work performed by, or delivered to, the working fluid. This universal scaling, which applies in the limit of small friction (W(fric)/W heat-engine efficiencies), allows a simple and quick estimate of the impact that friction losses can have on the FOM's of thermal engines and plants, or of the level of those losses from the observed and predicted FOM's. In the case of refrigerators and heat pumps, if W(fric)/W heat engines), the COP percentage decrease due to friction approaches asymptotically (W(fric)/W)/(1+W(fric)/W) instead of W(fric)/W. Estimates for the level of frictional losses using the Carnot (or, for heat engines and power plants only, the Curzon-Ahlborn) predictions and observed FOM's of real power plants, heat engines, refrigerators, and heat pumps show that they usually operate in domains where these behaviors are valid.

  10. Ceramic technology for advanced heat engines project. Semiannual progress report, April-September 1985

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-01

    An assessment of needs was completed, and a five-year project plan was developed with input from private industry. Objective is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. Focus is on structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. The work described in this report is organized according to the following WBS project elements: management and coordination; materials and processing (monolithics, ceramic composites, thermal and wear coatings, joining); materials design methodology (contact interfaces, new concepts); data base and life prediction (time-dependent behavior, environmental effects, fracture mechanics, NDE development); and technology transfer. This report includes contributions from all currently active project participants.

  11. The Importance of Thermal Heat Bridges in Civil Engineering

    Directory of Open Access Journals (Sweden)

    Adriana Tokar

    2011-10-01

    Full Text Available Based on the heat transfer characteristics of a construction, the expected temperatures along interior surfaces must be evaluated in order to predict (and avoid areas of potential moisture condensation. Beyond preventing damage to building materials caused by mould growth, adequate surface temperatures are also a relevant factor in the thermal comfort of an interior environment. An agreable climate in a room can be obtained, when relative humidity is between 40 and 60%. As the air in a room is warmer, the more vapor can absorb (and vice versa, influencing the thermal comfort index. Heat losses are influenced largely by thermal bridges of construction. The importance of the thermal heat bridges is strongly increasing today. In new developments the thermal optimization of junctions in today common low energy constructions receives very special standing. The subject of avoiding thermal bridges in passive houses became predominant.

  12. Hydrogen hybrid vehicle engine development: Experimental program

    Energy Technology Data Exchange (ETDEWEB)

    Van Blarigan, P. [Sandia National Lab., Livermore, CA (United States)

    1995-09-01

    A hydrogen fueled engine is being developed specifically for the auxiliary power unit (APU) in a series type hybrid vehicle. Hydrogen is different from other internal combustion (IC) engine fuels, and hybrid vehicle IC engine requirements are different from those of other IC vehicle engines. Together these differences will allow a new engine design based on first principles that will maximize thermal efficiency while minimizing principal emissions. The experimental program is proceeding in four steps: (1) Demonstration of the emissions and the indicated thermal efficiency capability of a standard CLR research engine modified for higher compression ratios and hydrogen fueled operation. (2) Design and test a new combustion chamber geometry for an existing single cylinder research engine, in an attempt to improve on the baseline indicated thermal efficiency of the CLR engine. (3) Design and build, in conjunction with an industrial collaborator, a new full scale research engine designed to maximize brake thermal efficiency. Include a full complement of combustion diagnostics. (4) Incorporate all of the knowledge thus obtained in the design and fabrication, by an industrial collaborator, of the hydrogen fueled engine for the hybrid vehicle power train illustrator. Results of the CLR baseline engine testing are presented, as well as preliminary data from the new combustion chamber engine. The CLR data confirm the low NOx produced by lean operation. The preliminary indicated thermal efficiency data from the new combustion chamber design engine show an improvement relative to the CLR engine. Comparison with previous high compression engine results shows reasonable agreement.

  13. [Development of domain specific search engines].

    Science.gov (United States)

    Takai, T; Tokunaga, M; Maeda, K; Kaminuma, T

    2000-01-01

    As cyber space exploding in a pace that nobody has ever imagined, it becomes very important to search cyber space efficiently and effectively. One solution to this problem is search engines. Already a lot of commercial search engines have been put on the market. However these search engines respond with such cumbersome results that domain specific experts can not tolerate. Using a dedicate hardware and a commercial software called OpenText, we have tried to develop several domain specific search engines. These engines are for our institute's Web contents, drugs, chemical safety, endocrine disruptors, and emergent response for chemical hazard. These engines have been on our Web site for testing.

  14. Sustainable Development in Engineering Education

    Science.gov (United States)

    Taoussanidis, Nikolaos N.; Antoniadou, Myrofora A.

    2006-01-01

    The principles and practice of environmentally and socially sustainable engineering are in line with growing community expectations and the strengthening voice of civil society in engineering interventions. Pressures towards internationalization and globalization are reflected in new course accreditation criteria and higher education structures.…

  15. Engineering Research in Irish Economic Development

    Science.gov (United States)

    Kelly, John

    2011-01-01

    This article summarizes the main findings and recommendations of a report published in December 2010 by the Irish Academy of Engineering (IAE). The report, representing the views of a committee of distinguished Irish engineers from a wide range of disciplines, addresses the role of engineering research in Ireland's economic development and the…

  16. How to Develop an Engineering Design Task

    Science.gov (United States)

    Dankenbring, Chelsey; Capobianco, Brenda M.; Eichinger, David

    2014-01-01

    In this article, the authors provide an overview of engineering and the engineering design process, and describe the steps they took to develop a fifth grade-level, standards-based engineering design task titled "Getting the Dirt on Decomposition." Their main goal was to focus more on modeling the discrete steps they took to create and…

  17. Consideration on nuclear fusion in plasma by the magnetic confinement as a heat engine

    International Nuclear Information System (INIS)

    Tsuji, Yoshio

    1990-01-01

    In comparing nuclear fusion in plasma by the magnetic confinement with nuclear fission and chemical reactions, the power density and the function of a heat engine are discussed using a new parameter G introduced as an eigenvalue of a reaction and the value of q introduced to estimate the thermal efficiency of a heat engine. It is shown that the fusion reactor by the magnetic confinement is very difficult to be a modern heat engine because of the lack of some indispensable functions as a modern heat engine. The value of G and q have the important role in the consideration. (author)

  18. Heat engines for dilatonic Born-Infeld black holes

    Energy Technology Data Exchange (ETDEWEB)

    Bhamidipati, Chandrasekhar; Yerra, Pavan Kumar [Indian Institute of Technology Bhubaneswar, School of Basic Sciences, Bhubaneswar (India)

    2017-08-15

    In the context of dilaton coupled Einstein gravity with a negative cosmological constant and a Born-Infeld field, we study heat engines where a charged black hole is the working substance. Using the existence of a notion of thermodynamic mass and volume (which depend on the dilaton coupling), the mechanical work takes place via the pdV terms present in the first law of extended gravitational thermodynamics. The efficiency is analyzed as a function of dilaton and Born-Infeld couplings, and the results are compared with analogous computations in the related conformal solutions in the Brans-Dicke-Born-Infeld theory and black holes in anti-de Sitter space-time. (orig.)

  19. Advanced materials for alternative fuel capable directly fired heat engines

    Energy Technology Data Exchange (ETDEWEB)

    Fairbanks, J.W.; Stringer, J. (eds.)

    1979-12-01

    The first conference on advanced materials for alternative fuel capable directly fired heat engines was held at the Maine Maritime Academy, Castine, Maine. It was sponsored by the US Department of Energy, (Assistant Secretary for Fossil Energy) and the Electric Power Research Institute, (Division of Fossil Fuel and Advanced Systems). Forty-four papers from the proceedings have been entered into EDB and ERA and one also into EAPA; three had been entered previously from other sources. The papers are concerned with US DOE research programs in this area, coal gasification, coal liquefaction, gas turbines, fluidized-bed combustion and the materials used in these processes or equipments. The materials papers involve alloys, ceramics, coatings, cladding, etc., and the fabrication and materials listing of such materials and studies involving corrosion, erosion, deposition, etc. (LTN)

  20. Development of Axial Compressor Heat-Extraction Capability for Thermal Management Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc. (ATA) proposes a small business innovation research (SBIR) program for a novel compressor heat-extraction development program in response to...

  1. Advanced heat exchanger development for molten salts

    Energy Technology Data Exchange (ETDEWEB)

    Sabharwall, Piyush, E-mail: Piyush.Sabharwall@inl.gov [Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Clark, Denis; Glazoff, Michael [Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Zheng, Guiqiu; Sridharan, Kumar; Anderson, Mark [University of Wisconsin, Madison (United States)

    2014-12-15

    Highlights: • Hastelloy N and 242, shows corrosion resistance to molten salt at nominal operating temperatures. • Both diffusion welds and sheet material in Hastelloy N were corrosion tested in at 650, 700, and 850 °C for 200, 500, and 1000 h. • Thermal gradients and galvanic couples in the molten salts enhance corrosion rates. • Corrosion rates found were typically <10 mils per year. - Abstract: This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non-nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, that show good corrosion resistance in molten salt at nominal operating temperatures up to 700 °C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet material in Hastelloy N were corrosion tested in 58 mol% KF and 42 mol% ZrF{sub 4} at 650, 700, and 850 °C for 200, 500, and 1000 h. Corrosion rates were similar between welded and nonwelded materials, typically <100 μm per year after 1000 h of corrosion tests. No catastrophic corrosion was observed in the diffusion welded regions. For materials of construction, nickel-based alloys and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of the type of salt impurity and alloy composition, with respect to chromium and carbon, to better define the best conditions for corrosion resistance. Also presented is the division of the nuclear reactor and high-temperature components per American Society of Mechanical

  2. Heat transfer in a compact tubular heat exchanger with application to the engine struts of the national aerospace plane

    International Nuclear Information System (INIS)

    Olsen, D.A.

    1991-01-01

    The authors constructed an apparatus to measure heat transfer coefficients in compact heat exchangers which are candidate cooling jackets for the engine struts of the National Aerospace Plane. This paper reports measurements on a tube specimen heat exchanger. The heat exchanger consisted of 20 nickel tubes (2 mm OD, 1 mm ID, 15.2 cm heated length), brazed to a 3 mm thick nickel plate. The tubes lay parallel to one another, 3.8 mm on-center separation. The heat exchanger was heated on one side in a radiative furnace at heat fluxes of 3.4 to 54 W/cm 2 over a normal area of 7.8 cm by 15.2 cm. The coolant fluid was helium gas at Reynolds numbers of 3000 to 35 000 and 3.50 MPa pressure. For high heat flux and low

  3. Development of maintenance engineering system

    International Nuclear Information System (INIS)

    1995-03-01

    Department of JMTR project has developed the Maintenance Engineering System which evaluates the aging tendency of the facilities. The system is used for the repair plan and the replace period of parts, components, equipments or facilities. The system has the data-base which consists of the check data, the inspection data, the trouble data and the repair data at the JMTR since the virgin criticality. The system is utilized maintenance works and concludes the maintenance procedures for the failure components, equipments and facilities. This system has the following characteristics. (1) Anybody can operate the system as easily as word processor. (2) Data are put into by man-machine-interface. (3) The data sheets are with light color and the recognizable arrangements. (4) The system is cost-efficient using commercial personal computers and applications. The research card and the layouts of the input data sheet had been formatted. Data has been begun to be put into the system and to check its functions. The result demonstrates that the system is available for preventive maintenance at the JMTR. (author)

  4. Optimum performance analysis of an irreversible Diesel heat engine affected by variable heat capacities of working fluid

    International Nuclear Information System (INIS)

    Zhao, Yingru; Chen, Jincan

    2007-01-01

    An irreversible cycle model of the Diesel heat engine is established in which the temperature dependent heat capacities of the working fluid, the irreversibilities resulting from non-isentropic compression and expansion processes and heat leak losses through the cylinder wall are taken into account. The adiabatic equation of ideal gases with temperature dependent heat capacity is strictly deduced without using the additional approximation condition in the relevant literature and is used to analyze the performance of the Diesel heat engine. Expressions for the work output and efficiency of the cycle are derived by introducing the pressure ratio and the compression and expansion efficiencies. The performance characteristic curves of the Diesel heat engine are presented for a set of given parameters. The optimum criteria of some important parameters such as the work output, efficiency, pressure ratio and temperatures of the working fluid are obtained. Moreover, the influence of the compression and expansion efficiencies, variable heat capacities, heat leak and other parameters on the performance of the cycle is discussed in detail. The results obtained may provide a theoretical basis for both optimal design and operation of real Diesel heat engines

  5. Novel thermoenvironmental evaluation criteria and comparing them for an actual heat engine

    International Nuclear Information System (INIS)

    Özel, Gülcan; Açıkkalp, Emin; Savaş, Ahmet Fevzi; Yamık, Hasan

    2015-01-01

    Highlights: • An irreversible Carnot cycle is considered. • Novel thermoenvironmental criteria are presented. • Calculation are conducted for irreversible cycles. • Numerical results are presented and discussed. - Abstract: In the present study, environmental impact analysis is used for the optimization to an actual heat engine. Four new thermoenvironmental evaluation criteria called as thermoenvironmental function, ecological based thermoenvironmental function, ecologicoenvironmental function and finite time exergoenvironmental criteria are developed and compared with the each other. Ecologicoenvironmental function is used to determine environmental impact at the maximum ecological function. It is defined as the most suitable criteria for an actual heat engine. Because, it has lower irreversibilities compared with others, its work output is equal to 90% of the maximum work and 60% energy efficiency at the optimum point and exergy destruction is lower than others at the optimum point.

  6. ICF ETF and its engineering development requirements

    International Nuclear Information System (INIS)

    Blink, J.A.; Allen, W.O.; Billman, K.

    1980-10-01

    Inertial confinement fusion driver development and ICF target physics are being intensively explored both theoretically and experimentally. However, engineering considerations of harnessing the fusion energy pulses that are an ultimate product and goal of the ICF physics program are only being addressed on a small scale. Experience with development of other new technologies indicates that engineering development time will be substantial for ICF energy converters. The authors met at Livermore in July 1980 to form an ICF Reactor Technology Working Group to address this issue. This paper outlines the current state of planning for an ICF Engineering Test Facility (ETF) and the engineering development that must precede it

  7. Equipment for heating the exhaust gases of internal combustion engines in order to improve afterburning

    Energy Technology Data Exchange (ETDEWEB)

    Masaki,

    1976-04-15

    The device described here serves to heat exhaust gases of internal combustion engines by heat exchange with hot gases and also, in cold engines, to raise the temperature of the fuel-air mixture drawn in by the engine. The device is installed next to the outlet opening of the engine. It consists of a burner to generate the hot gas, as well as a heat exchanger permitting heat supply to the exhaust gases and a hot-gas line leading to the intake line. Heating of the air is taken in leads to a better atomization of the mixture and thus to improved combustion. Heating of the exhaust gases improves afterburning. The burner generating the hot gas is shut off when the normal operational temperature of the engine is reached. The temperature is controlled by means of a temperature sensor installed in the device.

  8. Model based development of engine control algorithms

    NARCIS (Netherlands)

    Dekker, H.J.; Sturm, W.L.

    1996-01-01

    Model based development of engine control systems has several advantages. The development time and costs are strongly reduced because much of the development and optimization work is carried out by simulating both engine and control system. After optimizing the control algorithm it can be executed

  9. Development of natural gas rotary engines

    Science.gov (United States)

    Mack, J. R.

    1991-08-01

    Development of natural gas-fueled rotary engines was pursued on the parallel paths of converted Mazda automotive engines and of establishing technology and demonstration of a test model of a larger John Deer Technologies Incorporated (JDTI) rotary engine with power capability of 250 HP per power section for future production of multi-rotor engines with power ratings 250, 500, and 1000 HP and upward. Mazda engines were converted to natural gas and were characterized by a laboratory which was followed by nearly 12,000 hours of testing in three different field installations. To develop technology for the larger JDTI engine, laboratory and engine materials testing was accomplished. Extensive combustion analysis computer codes were modified, verified, and utilized to predict engine performance, to guide parameters for actual engine design, and to identify further improvements. A single rotor test engine of 5.8 liter displacement was designed for natural gas operation based on the JDTI 580 engine series. This engine was built and tested. It ran well and essentially achieved predicted performance. Lean combustion and low NOW emission were demonstrated.

  10. An investigation of heat recovery of submarine diesel engines for combined cooling, heating and power systems

    International Nuclear Information System (INIS)

    Daghigh, Roonak; Shafieian, Abdellah

    2016-01-01

    Highlights: • The power output of the cycle is about 53 kW in the mass flow rate of 0.6 kg/s. • The output cooling water temperature of evaporator is 3.64 °C. • The absorption chiller has a coefficient of performance equal to 0.94. - Abstract: High temperature and mass flow rate of the exhaust gases of submarine diesel engines provide an appropriate potential for their thermal recovery. The current study introduces a combined cooling, heating and power system for thermal recovery of submarine diesel engines. The cooling system is composed of a mixed effect absorption chiller with two high and low pressure generators. The exhaust of the diesel engine is used in the high pressure generator, and the low pressure generator was divided into two parts. The required heat for the first and second compartments is supplied by the cooling water of the engine and condensation of the vapor generated in the high pressure generator, respectively. The power generation system is a Rankine cycle with an organic working fluid, which is considered a normal thermal system to supply hot water. The whole system is encoded based on mass stability, condensation and energy equations. The obtained findings showed that the maximum heat recovery for the power cycle occurs in exhaust gas mass ratio of 0.23–0.29 and working fluid mass flow rate of 0.45–0.57 kg/s. Further, for each specific mass ratio of exhaust gas, only a certain range of working fluid mass flow rate is used. In the refrigerant mass flow rate of 0.6 kg/s and exhaust gas mass ratio of 0.27, the power output of the cycle is 53 kW, which can also be achieved by simultaneous increase of refrigerant mass flow rate and exhaust gas mass ratio in a certain range of higher powers. In the next section, the overall distribution diagram of output water temperature of the thermal system is obtained according to the exhaust gas mass ratio in various mass flow rates, which can increase the potential of designing and controlling the

  11. Micro power/heat cogeneration incorporating a stirling engine

    International Nuclear Information System (INIS)

    Luft, S.

    2003-01-01

    The Stirling-engine for CHP-purpose developed by SOLO is a trend-setting technology. It represents the most suspicious perspective apart from the fuel-cell technology in order to become suitable to the requirements of the future power supply in the focus of the sustainability and the decentralized energy supply. The charm of the Stirling technology is based on the external combustion: a so far not known variability with the primary energy choice as well as a life span substantially extending, wear-free operation are possible thereby. The external combustion reduces also the maintenance and the emissions in a measure not known with conventional engine technologies. The development steps are finished. The result is the world-wide first concept for the commercial, stationary application of decentralized micro-CHP on Stirling technology basis, which goes into series. (orig.) [de

  12. Optimum performance characteristics of a solar-driven Stirling heat engine system

    International Nuclear Information System (INIS)

    Liao, Tianjun; Lin, Jian

    2015-01-01

    Graphical abstract: T–S diagram of the SHE cycle. - Highlights: • Based on Lagrange multiplier method, the optimal performance are investigated. • The energy balance between the absorber and the hot side of Stirling heat engine is considered. • The effects of major parameters on the optimal performance are investigated. - Abstract: A solar-driven Stirling heat engine system composed of a Stirling heat engine, a solar collector, and a heat sink is presented, in which the radiation and convection heat losses of the solar collector, the heat-leak between the thermal absorber and heat sink, the regenerative losses of the Stirling heat engine, and the energy balance between the thermal absorber and the high isothermal process of the Stirling heat engine are taken into consideration. Based on the irreversible thermodynamics and Lagrange multiplier method, the maximum power output and the corresponding optimal efficiency of the system are determined and the absorber temperature that maximizes the optimal system efficiency is calculated numerically. The influences of some system parameters such as the concentrating ratio, the volume ratio during the regenerative processes and irreversibilities of heat exchange processes on the optimal efficiency are analyzed in details. The results obtained here may provide a new idea to design practical solar-driven Stirling heat engine system

  13. The Development of Precise Engineering Surveying Technology

    Directory of Open Access Journals (Sweden)

    LI Guangyun

    2017-10-01

    Full Text Available With the construction of big science projects in China, the precise engineering surveying technology developed rapidly in the 21th century. Firstly, the paper summarized up the current development situation for the precise engineering surveying instrument and theory. Then the three typical cases of the precise engineering surveying practice such as accelerator alignment, industry measurement and high-speed railway surveying technology are focused.

  14. An analytical study on the performance of the organic Rankine cycle for turbofan engine exhaust heat recovery

    Science.gov (United States)

    Saadon, S.; Abu Talib, A. R.

    2016-10-01

    Due to energy shortage and global warming, issues of energy saving have become more important. To increase the energy efficiency and reduce the fuel consumption, waste heat recovery is a significant method for energy saving. The organic Rankine cycle (ORC) has great potential to recover the waste heat from the core jet exhaust of a turbofan engine and use it to produce power. Preliminary study of the design concept and thermodynamic performance of this ORC system would assist researchers to predict the benefits of using the ORC system to extract the exhaust heat engine. In addition, a mathematical model of the heat transfer of this ORC system is studied and developed. The results show that with the increment of exhaust heat temperature, the mass flow rate of the working fluid, net power output and the system thermal efficiency will also increase. Consequently, total consumption of jet fuel could be significantly saved as well.

  15. Optimal piston motion for maximum net output work of Daniel cam engines with low heat rejection

    International Nuclear Information System (INIS)

    Badescu, Viorel

    2015-01-01

    Highlights: • The piston motion of low heat rejection compression ignition engines is optimized. • A realistic model taking into account the cooling system is developed. • The optimized cam is smaller for cylinders without thermal insulation. • The optimized cam size depends on ignition moment and cooling process intensity. - Abstract: Compression ignition engines based on classical tapper-crank systems cannot provide optimal piston motion. Cam engines are more appropriate for this purpose. In this paper the piston motion of a Daniel cam engine is optimized. Piston acceleration is taken as a control. The objective is to maximize the net output work during the compression and power strokes. A major research effort has been allocated in the last two decades for the development of low heat rejection engines. A thermally insulated cylinder is considered and a realistic model taking into account the cooling system is developed. The sinusoidal approximation of piston motion in the classical tapper-crank system overestimates the engine efficiency. The exact description of the piston motion in tapper-crank system is used here as a reference. The radiation process has negligible effects during the optimization. The approach with no constraint on piston acceleration is a reasonable approximation. The net output work is much larger (by 12–13%) for the optimized system than for the classical tapper-crank system, for similar thickness of cylinder walls and thermal insulation. Low heat rejection measures are not of significant importance for optimized cam engines. The optimized cam is smaller for a cylinder without thermal insulation than for an insulated cylinder (by up to 8%, depending on the local polar radius). The auto-ignition moment is not a parameter of significant importance for optimized cam engines. However, for given cylinder wall and insulation materials there is an optimum auto-ignition moment which maximizes the net output work. The optimum auto

  16. Origin and type of flaws in heat engine ceramic materials and components

    International Nuclear Information System (INIS)

    Govila, R.K.

    1995-01-01

    A number of ceramic materials such as Silicon Nitrides and Carbides, Sialons, Whisker-Reinforced Ceramic Composites and Partially-Stabilized Zirconias (PSZs) have been developed for use as structural components in heat engine applications. The reliability and durability of a structural engine component is critically dependent on the size, density of distribution and location of flaws. This information is critical for the processing and design engineers in order to design structural components using suitable materials and thus minimize stress intensity. In general, the failure initiating flaws are associated or produced due to material impurity, processing methods and parameters, and fabrication techniques (machining and grinding). Examples of each type of flaws associated with material impurity, processing methods and fabrication techniques are illustrated

  17. Regressed relations for forced convection heat transfer in a direct injection stratified charge rotary engine

    Science.gov (United States)

    Lee, Chi M.; Schock, Harold J.

    1988-01-01

    Currently, the heat transfer equation used in the rotary combustion engine (RCE) simulation model is taken from piston engine studies. These relations have been empirically developed by the experimental input coming from piston engines whose geometry differs considerably from that of the RCE. The objective of this work was to derive equations to estimate heat transfer coefficients in the combustion chamber of an RCE. This was accomplished by making detailed temperature and pressure measurements in a direct injection stratified charge (DISC) RCE under a range of conditions. For each specific measurement point, the local gas velocity was assumed equal to the local rotor tip speed. Local physical properties of the fluids were then calculated. Two types of correlation equations were derived and are described in this paper. The first correlation expresses the Nusselt number as a function of the Prandtl number, Reynolds number, and characteristic temperature ratio; the second correlation expresses the forced convection heat transfer coefficient as a function of fluid temperature, pressure and velocity.

  18. Interdisciplinary Integrated Engineering Development Course in HITACHI

    Science.gov (United States)

    Ojima, Masahiro

    As an example of interdisciplinary education for engineers in private companies, IED (Integrated Engineering Development) course at HITACHI Ltd. is presented. To help 30 years old or so promising engineers create a new product based on a new technology, one year term course is designed for four types of engineers; mechanical, electric & electronic, information software, and digital systems. Each course has core basic technologies plus related supplementary subjects to promote an interdisciplinary integrated engineer. Not only lectures given by university professors but heavy duty home work is also given by senior engineers of HITACHI to make them apply basic theory to practical problems. Furthermore, self development planning, leadership development program and technology-marketing project are introduced to promote human skills and business sense needed for technology leaders in company.

  19. Automotive Stirling engine development program: A success

    Science.gov (United States)

    Tabata, W. K.

    1987-01-01

    The original 5-yr Automotive Stirling Engine Development Program has been extended to 10 years due to reduced annual funding levels. With an estimated completion date of April 1988, the technical achievements and the prospectives of meeting the original program objectives are reviewed. Various other applications of this developed Stirling engine technology are also discussed.

  20. Hydrothermal industrialization: direct heat development. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-01

    A description of hydrothermal resources suitable for direct applications, their associated temperatures, geographic distribution and developable capacity are given. An overview of the hydrothermal direct-heat development infrastructure is presented. Development activity is highlighted by examining known and planned geothermal direct-use applications. Underlying assumptions and results for three studies conducted to determine direct-use market penetration of geothermal energy are discussed.

  1. Product design and development engineering

    International Nuclear Information System (INIS)

    Lee, Kookhwan

    2008-01-01

    This book gives design of molded plastics, design of press product, design of die casting products, the application of communication terminal design, application and design of machine elements(screw, spring, bearing, gear, retaining ridge, drawing standards, KS and JIS material marks list), 3D CAD, concurrent engineering of product design, creative concept design.

  2. Creativity Development for Engineering Students

    DEFF Research Database (Denmark)

    Zhou, Chunfang; Holgaard, Jette Egelund; Kolmos, Anette

    2010-01-01

    In this paper we outline two approaches to enhance creative skills in a PBL environment at Aalborg University, Denmark. The two strategies are respectively characterized by 1) integrating creativity training into curriculum and 2) introducing real life engineering projects for students. Two cases...

  3. Piston surface heat transfer during combustion in large marine diesel engines

    DEFF Research Database (Denmark)

    Jensen, Michael Vincent; Walther, Jens Honore

    2010-01-01

    In the design process of large marine diesel engines information on the maximum heat load on the piston surface experienced during the engine cycle is an important parameter. The peak heat load occurs during combustion when hot combustion products impinge on the piston surface. Although the maximum...... heat load is only present for a short time of the total engine cycle, it is a severe thermal load on the piston surface. At the same time, cooling of the piston crown is generally more complicated than cooling of the other components of the combustion chamber. This can occasionally cause problems...... with burning off piston surface material. In this work the peak heat load on the piston surface of large marine diesel engines during combustion was investigated. Measurements of the instantaneous surface temperature and surface heat flux on pistons in large marine engines are difficult due to expensive...

  4. Performance and efficiency evaluation and heat release study of a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Nguyen, H. L.; Addy, H. E.; Bond, T. H.; Lee, C. M.; Chun, K. S.

    1987-01-01

    A computer simulation which models engine performance of the Direct Injection Stratified Charge (DISC) rotary engines was used to study the effect of variations in engine design and operating parameters on engine performance and efficiency of an Outboard Marine Corporation (OMC) experimental rotary combustion engine. Engine pressure data were used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine data were compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the rotary engine using advanced heat engine concepts such as faster combustion, reduced leakage, and turbocharging is also presented.

  5. Light-duty diesel engine development status and engine needs

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    This report reviews, assesses, and summarizes the research and development status of diesel engine technology applicable to light-duty vehicles. In addition, it identifies specific basic and applied research and development needs in light-duty diesel technology and related health areas where initial or increased participation by the US Government would be desirable. The material presented in this report updates information provided in the first diesel engine status report prepared by the Aerospace Corporation for the Department of Energy in September, 1978.

  6. Development of engineering scale HLLW vitrification technique at PNC

    International Nuclear Information System (INIS)

    Nagaki, H.; Oguino, N.; Tsunoda, N.; Segawa, T.

    1979-01-01

    Some processes have been investigated to develop the technology of solidification of the high-level radioactive liquid waste generated from the nuclear fuel reprocessing plant operated by the Power Reactor and Nuclear Fuel Development Corporation (PNC) at Tokai-mura. This report covers the present state of development of a Joule-heated ceramic melter and a direct megahertz induction-heated melter. Engineering-scale tests have been performed with both melters. The Joule-heated melter could produce 45 kg or 16 liters of glass per hour. The direct-induction furnace was able to melt 5 kg or 1.8 liters of glass per hour. Both melters were composed of electrofused cast refractory brick. Thus it was possible to melt the glass at above 1200 0 C. Glass produced at higher melting temperatures is generally superior. 3 figures, 2 tables

  7. Membrane Engineering for Sustainable Development: A Perspective

    OpenAIRE

    Aamer Ali; Enrico Drioli; Francesca Macedonio

    2017-01-01

    Membrane engineering can offer an important contribution in realizing sustainable industrial development. It provides opportunities to redesign the conventional process of engineering in the logic of Process Intensification. Relatively new and less exploited membrane operations offer innovative solutions to the scarcity of raw materials, freshwater and energy. Here, we identify the most interesting aspects of membrane engineering in some strategic industrial sectors. Several cases of either s...

  8. Universality of energy conversion efficiency for optimal tight-coupling heat engines and refrigerators

    International Nuclear Information System (INIS)

    Sheng, Shiqi; Tu, Z C

    2013-01-01

    A unified χ-criterion for heat devices (including heat engines and refrigerators), which is defined as the product of the energy conversion efficiency and the heat absorbed per unit time by the working substance (de Tomás et al 2012 Phys. Rev. E 85 010104), is optimized for tight-coupling heat engines and refrigerators operating between two heat baths at temperatures T c and T h ( > T c ). By taking a new convention on the thermodynamic flux related to the heat transfer between two baths, we find that for a refrigerator tightly and symmetrically coupled with two heat baths, the coefficient of performance (i.e., the energy conversion efficiency of refrigerators) at maximum χ asymptotically approaches √(ε C ) when the relative temperature difference between two heat baths ε C -1 ≡(T h -T c )/T c is sufficiently small. Correspondingly, the efficiency at maximum χ (equivalent to maximum power) for a heat engine tightly and symmetrically coupled with two heat baths is proved to be η C /2+η C 2 /8 up to the second order term of η C ≡ (T h − T c )/T h , which reverts to the universal efficiency at maximum power for tight-coupling heat engines operating between two heat baths at small temperature difference in the presence of left–right symmetry (Esposito et al 2009 Phys. Rev. Lett. 102 130602). (fast track communication)

  9. Stirling engine or heat pump having an improved seal

    Science.gov (United States)

    White, Maurice A.; Riggle, Peter; Emigh, Stuart G.

    1985-01-01

    A Stirling Engine or Heat Pump having two relatively movable machine elements for power transmission purposes includes a hermetic seal bellows interposed between the elements for separating a working gas from a pressure compensating liquid that balances pressure across the bellows to reduce bellows stress and to assure long bellows life. The volume of pressure compensating liquid displaced due to relative movement between the machine elements is minimized by enclosing the compensating liquid within a region exposed to portions of both machine elements at one axial end of a slidable interface presented between them by a clearance seal having an effective diameter of the seal bellows. Pressure equalization across the bellows is achieved by a separate hermetically sealed compensator including a movable enclosed bellows. The interior of the compensator bellows is in communication with one side of the seal bellows, and its exterior is in communication with the remaining side of the seal bellows. A buffer gas or additional liquid region can be provided at the remaining axial end of the clearnace seal, along with valved arrangements for makeup of liquid leakage through the clearance seal.

  10. Possible directions for using bran in heat-power engineering

    Directory of Open Access Journals (Sweden)

    Gaydabrus Maria

    2017-01-01

    Full Text Available In connection with the necessity of providing of ecofriendlyness of energy the researches sent to the increase of stake of biomass in fuel and energy balance are actual direction of science and technique. The aim of work is put the study of heating engineering properties of bran and research of possibility of briquetting as it applies to the power use in the stratified fire-box devices. Research methods included standard methodologies of ISO and physical experiment. It is shown as a result of research that bran on the warmth of combustion is comparable with brown coals, but has a less ash-content considerably. However shallow factious composition of bran and caking in the process of ashing will result in high operating costs at their incineration in a natural kind. The variant of the power use of bran is considered as the preforms got the thermal pressing, and the optimal temperature of pressing, equal 150°C. On the example of pressing of shell of cedar nuts possibility of the use of bran is shown as connective, is set here.

  11. Reversible and irreversible heat engine and refrigerator cycles

    Science.gov (United States)

    Leff, Harvey S.

    2018-05-01

    Although no reversible thermodynamic cycles exist in nature, nearly all cycles covered in textbooks are reversible. This is a review, clarification, and extension of results and concepts for quasistatic, reversible and irreversible processes and cycles, intended primarily for teachers and students. Distinctions between the latter process types are explained, with emphasis on clockwise (CW) and counterclockwise (CCW) cycles. Specific examples of each are examined, including Carnot, Kelvin and Stirling cycles. For the Stirling cycle, potentially useful task-specific efficiency measures are proposed and illustrated. Whether a cycle behaves as a traditional refrigerator or heat engine can depend on whether it is reversible or irreversible. Reversible and irreversible-quasistatic CW cycles both satisfy Carnot's inequality for thermal efficiency, η ≤ η C a r n o t . Irreversible CCW cycles with two reservoirs satisfy the coefficient of performance inequality K ≤ K C a r n o t . However, an arbitrary reversible cycle satisfies K ≥ K C a r n o t when compared with a reversible Carnot cycle operating between its maximum and minimum temperatures, a potentially counterintuitive result.

  12. Cascade fuzzy control for gas engine driven heat pump

    International Nuclear Information System (INIS)

    Li Shuze; Zhang Wugao; Zhang Rongrong; Lv Dexu; Huang Zhen

    2005-01-01

    In addition to absorption chillers, today's gas cooling technology includes gas engine driven heat pump systems (GEHP) in a range of capacities and temperature capacities suitable for most commercial air conditioning and refrigeration applications. Much is expected from GEHPs as a product that would help satisfy the air conditioning system demand from medium and small sized buildings, restrict electric power demand peaks in summer and save energy in general. This article describes a kind of control strategy for a GEHP, a cascade fuzzy control. GEHPs have large and varying time constants and their dynamic modeling cannot be easily achieved. A cascade control strategy is effective for systems that have large time constants and disturbances, and a fuzzy control strategy is fit for a system that lacks an accurate model. This cascade fuzzy control structure brings together the best merits of fuzzy control and cascade control structures. The performance of the cascade fuzzy control is compared to that of a cascade PI (proportional and integral) control strategy, and it is shown by example that the cascade fuzzy control strategy gives a better performance, reduced reaction time and smaller overshoot temperature

  13. A novel transient wall heat transfer approach for the start-up of SI engines with gasoline direct injection

    Science.gov (United States)

    Lejsek, David; Kulzer, André; Hammer, Jürgen

    2010-11-01

    The introduction of CO2-reduction technologies like Start-Stop or the Hybrid-Powertrain and the worldwide stringent emission legislation require a detailed optimization of the engine start-up. The combustion concept development as well as the calibration of the engine control unit makes an explicit thermodynamic analysis of the combustion process during the start-up necessary. Initially, the well-known thermodynamic analysis of in-cylinder pressure at stationary condition was transmitted to the highly non-stationary engine start-up. For this running mode of the engine the current models for calculation of the transient wall heat fluxes were found to be misleading. With a fraction of nearly 45% of the burned fuel energy, the wall heat is very important for the calculation of energy balance and for the combustion process analysis. Based on the measurements of transient wall heat transfer densities during the start-up presented in a former work (Lejsek and Kulzer in Investigations on the transient wall heat transfer at start-up for SI engines with gasoline direct injection. SAE Paper), the paper describes the development of adaptations to the known correlations by Woschni (MTZ 31:491, 1970), Hohenberg (Experimentelle Erfassung der Wandwärme von Kolbenmotoren. TU Graz, Habil., 1980) and Bargende (Ein Gleichungsansatz zur Berechnung der instationären Wandwärmeverluste im Hochdruckteil von Ottomotoren. TH Darmstadt, PhD-Thesis, 1991) for the application during engine start-up. To demonstrate the high accuracy of the model, the results of the cyclic resolved thermodynamic analysis using the presented novel approaches were compared with the results of the measurements. It is shown, that the novel heat flux models for the engine start-up process gives a cyclic resolved thermodynamic analysis to optimize the engine start-up pretty efficient.

  14. Neutral-beam-heating applications and development

    International Nuclear Information System (INIS)

    Menon, M.M.

    1981-01-01

    The technique of heating the plasma in magnetically confined fusion devices by the injection of intense beams of neutral atoms is described. The basic principles governing the physics of neutral beam heating and considerations involved in determining the injection energy, power, and pulse length required for a fusion reactor are discussed. The pertinent experimental results from various fusion devices are surveyed to illustrate the efficacy of this technique. The second part of the paper is devoted to the technology of producing the neutral beams. A state-of-the-art account o the development of neutral injectors is presented, and the prospects for utilizing neutral injection to heat the plasma in a fusion reactor are examined

  15. Development of heat-resistant magnetic sensor

    International Nuclear Information System (INIS)

    Takaya, Shigeru; Arakawa, Hisashi; Keyakida, Satoshi

    2013-01-01

    A heat-resistant flux gate magnetic sensor has been developed. Permendur, which has high Curie point, is employed as the magnetic core material and the detection method of the external magnetic field is modified. The characteristics of the developed magnetic sensor up to 500degC were evaluated. The sensor output increased linearly with the external magnetic field in the range of ±5 G and the standard deviation at 500degC was about 0.85G. (author)

  16. Impact of Dissociation and Sensible Heat Release on Pulse Detonation and Gas Turbine Engine Performance

    Science.gov (United States)

    Povinelli, Louis A.

    2001-01-01

    A thermodynamic cycle analysis of the effect of sensible heat release on the relative performance of pulse detonation and gas turbine engines is presented. Dissociation losses in the PDE (Pulse Detonation Engine) are found to cause a substantial decrease in engine performance parameters.

  17. Developing marketing system for civil engineering firm

    Directory of Open Access Journals (Sweden)

    Jovićević Ratko

    2006-01-01

    Full Text Available In this paper intention was to reveal insufficient connection between theory and practice in civil engineering as indispose condition for more efficient solving problems which products unstable environment of engineering firms. Successful connection between theory and practice, when we talk about marketing in civil engineering, did not develop at satisfied way. Civil engineering is, in aspect of implementation of modern philosophy of marketing, in big residue related to the other spices of economy. In that order we want to appoint on possibility to resolve this discrepancy.

  18. Dictionary of combustion engineering and heating engineering. Pt. 1. Woerterbuch der Feuerungs- und Heizungstechnik. T. 1. - Encyclopedie de la technique de combustion et de chauffage. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Katz, M

    1984-01-01

    The dictionary lists technical terms of the fields of combustion engineering and heating engineering. The heating engineering part was kept as short as possible; only those terms are listed, that are directly or indirectly related to combustion engineering. Contents: Definitions, standard nomenclature, burner systems, treatment systems, burner components, dictionary, SI-units, drawings with translations. 26 figs.

  19. Development of multilayer constructs for tissue engineering

    NARCIS (Netherlands)

    Bettahalli, N. M. S.; Groen, N.; Steg, H.; Unadkat, H.; de Boer, J.; van Blitterswijk, C. A.; Wessling, M.; Stamatialis, D.

    The rapidly developing field of tissue engineering produces living substitutes that restore, maintain or improve the function of tissues or organs. In contrast to standard therapies, the engineered products become integrated within the patient, affording a potentially permanent and specific cure of

  20. Development of multilayer constructs for tissue engineering

    NARCIS (Netherlands)

    Bettahalli Narasimha, M.S.; Groen, N.; Steg, H.; Unadkat, H.V.; de Boer, Jan; van Blitterswijk, Clemens; Wessling, Matthias; Stamatialis, Dimitrios

    2014-01-01

    The rapidly developing field of tissue engineering produces living substitutes that restore, maintain or improve the function of tissues or organs. In contrast to standard therapies, the engineered products become integrated within the patient, affording a potentially permanent and specific cure of

  1. Integrated diesel engine NOx reduction technology development

    Energy Technology Data Exchange (ETDEWEB)

    Hoelzer, J.; Zhu, J.; Savonen, C.L. [Detroit Diesel Corp., MI (United States); Kharas, K.C.C.; Bailey, O.H.; Miller, M.; Vuichard, J. [Allied Signal Environmental Catalysts, Tulsa, OK (United States)

    1997-12-31

    The effectiveness of catalyst performance is a function of the inlet exhaust gas temperature, gas flow rate, concentration of NO{sub x} and oxygen, and reductant quantity and species. Given this interrelationship, it becomes immediately clear that an integrated development approach is necessary. Such an approach is taken in this project. As such, the system development path is directed by an engine-catalyst engineering team. Of the tools at the engine engineer`s disposal the real-time aspects of computer assisted subsystem modeling is valuable. It will continue to be the case as ever more subtle improvements are needed to meet competitive performance, durability, and emission challenges. A review of recent prototype engines has shown that considerable improvements to base diesel engine technology are being made. For example, HSDI NO{sub x} has been reduced by a factor of two within the past ten years. However, additional substantial NO{sub x}/PM reduction is still required for the future. A viable lean NO{sub x} catalyst would be an attractive solution to this end. The results of recent high and low temperature catalyst developments were presented. High temperature base metal catalysts have been formulated to produce very good conversion efficiency and good thermal stability, albeit at temperatures near the upper range of diesel engine operation. Low temperature noble metal catalysts have been developed to provide performance of promising 4-way control but need increased NO{sub x} reduction efficiency.

  2. Development of the Heated Length Correction Factor

    International Nuclear Information System (INIS)

    Park, Ho-Young; Kim, Kang-Hoon; Nahm, Kee-Yil; Jung, Yil-Sup; Park, Eung-Jun

    2008-01-01

    The Critical Heat Flux (CHF) on a nuclear fuel is defined by the function of flow channel geometry and flow condition. According to the selection of the explanatory variable, there are three hypotheses to explain CHF at uniformly heated vertical rod (inlet condition hypothesis, exit condition hypothesis, local condition hypothesis). For inlet condition hypothesis, CHF is characterized by function of system pressure, rod diameter, rod length, mass flow and inlet subcooling. For exit condition hypothesis, exit quality substitutes for inlet subcooling. Generally the heated length effect on CHF in exit condition hypothesis is smaller than that of other variables. Heated length is usually excluded in local condition hypothesis to describe the CHF with only local fluid conditions. Most of commercial plants currently use the empirical CHF correlation based on local condition hypothesis. Empirical CHF correlation is developed by the method of fitting the selected sensitive local variables to CHF test data using the multiple non-linear regression. Because this kind of method can not explain physical meaning, it is difficult to reflect the proper effect of complex geometry. So the recent CHF correlation development strategy of nuclear fuel vendor is making the basic CHF correlation which consists of basic flow variables (local fluid conditions) at first, and then the geometrical correction factors are compensated additionally. Because the functional forms of correction factors are determined from the independent test data which represent the corresponding geometry separately, it can be applied to other CHF correlation directly only with minor coefficient modification

  3. Formulation and validation of applied engineering equations for heat transfer processes in the food industry

    DEFF Research Database (Denmark)

    Christensen, Martin Gram

    The study is focused on convective heat transfer in the processing of solid foods, specifically with the scope to develop simple analytical calculation tools that can be incorporated into spreadsheet solutions. In areas of food engineering such as equipment manufacture the use of predictive...... calculations, modelling activities and simulations for improved design is employed to a high degree. In food manufacture the use process calculations are seldom applied. Even though, the calculation of thermal processes is not a challenging task in academia; this is not the case for food manufacture. However......; the calculations need fundamental validation and a generality that ensures a wide application, thus also the development of simplified approximations and engineering equations have to be conducted in academia. The focus group for the utilization of the presented work is; food manufacture, authorities ensuring food...

  4. Elements of learning technologies designing of engineering networks heat

    Directory of Open Access Journals (Sweden)

    Sidorkina Irina G.

    2016-01-01

    Full Text Available Modern educational systems function as a medium fast analysis of shared information that defines them as analytical. The purpose of analytical information processing systems: working with distributed data on a global computer networks, mining and processing of semi structured information, knowledge. Existing mathematical and heuristic methods for the automated synthesis of electronic courses and their corresponding algorithms do not allow the full compliance of development realized in the form of adequate criteria for the totality of the properties distributed educational systems within acceptable time limits and characteristic. Therefore, the development of electronic educational applications must be accompanied by a variety of software support intelligent and adaptive functions. In addition, there is no theoretical justification for integrative aspects and their practical applications for intelligent and adaptive systems of designing distance learning courses. Currently, this type of problem may be considered as a potentially promising. The article presents the functionality of the e-learning course on the design engineering of thermal networks, process modeling in engineering networks with the solution of energy efficiency, detection of problem areas; identify the irrational layout of heaters and others.

  5. Quantum Stirling heat engine and refrigerator with single and coupled spin systems

    Science.gov (United States)

    Huang, Xiao-Li; Niu, Xin-Ya; Xiu, Xiao-Ming; Yi, Xue-Xi

    2014-02-01

    We study the reversible quantum Stirling cycle with a single spin or two coupled spins as the working substance. With the single spin as the working substance, we find that under certain conditions the reversed cycle of a heat engine is NOT a refrigerator, this feature holds true for a Stirling heat engine with an ion trapped in a shallow potential as its working substance. The efficiency of quantum Stirling heat engine can be higher than the efficiency of the Carnot engine, but the performance coefficient of the quantum Stirling refrigerator is always lower than its classical counterpart. With two coupled spins as the working substance, we find that a heat engine can turn to a refrigerator due to the increasing of the coupling constant, this can be explained by the properties of the isothermal line in the magnetic field-entropy plane.

  6. Reactors for heat production and the development of district heating in France

    International Nuclear Information System (INIS)

    Ricateau, P.

    1977-01-01

    Hitherto the development of nuclear power engineering has been based on the generation of electricity, and even of base-load electricity for feeding into a grid covering an entire country. Definition of the service to be rendered by a nuclear power station was thus extremely simple, namely to supply electricity throughout the year at the lowest possible cost and with the maximum possible reliability. Between the reactor on the one hand and the consumers on the other - consumers whose requirements are very diverse and who are geographically widely scattered - the grid forms a sort of screen so that the optimization of the reactor hardly depends at all on the configuration of the remainder of the transmission and distribution system. The production of heat involves totally different problems, for two essential reasons: (a) the limited economic range for the distribution of heat which limits the reactor to a specific group of consumers, and (b) the fact that the temperature, unlike the electrical potential, cannot be transformed at will but drops continuously between production and consumption of the heat. The temperature of the reactor must be matched to the nature of consumer demand and to the distance over which the heat must be transported. The heat balance thus appears to be like that of a system in which source, transmission and utilization are closely related. In these conditions the solutions will depend on numerous factors and one should not be surprised at finding different applications of nuclear power not only from one country to another but even from one area to another within the same country. The author first outlines the characteristics of the demand for district heating in France and then examines the types of nuclear plant which seem best suited for this purpose in the French context. (author)

  7. Heat transfer comparison between methane and hydrogen in a spark ignited engine

    Energy Technology Data Exchange (ETDEWEB)

    Sierens, Roger; Demuynck, Joachim; Paepe, Michel de; Verhelst, Sebastian [Ghent Univ. (Belgium)

    2010-07-01

    Hydrogen is one of the alternative fuels which are being investigated at Ghent University. NO{sub x} emissions will occur at high engine loads and they are a constraint for power and efficiency optimization. The formation of NO{sub x} emissions is temperature dependent. Consequently, the heat transfer from the burning gases to the cylinder walls has to be accurately modelled if precise computer calculations of the emissions are wanted. Several engine heat transfer models exist but they have been cited to be inaccurate for hydrogen. We have measured the heat flux in a spark ignited engine with a commercially available heat flux sensor. This paper investigates the difference between the heat transfer of hydrogen and a fossil fuel, in this case methane. Measurements with the same indicated power output are compared and the effect of the heat loss on the indicated efficiency is investigated. The power output of hydrogen combustion is lowered by burning lean in contrast to using a throttle in the case of methane. Although the peak in the heat flux of hydrogen is 3 times higher compared to methane for a high engine power output, the indicated efficiency is only 3% lower. The heat loss for hydrogen at a low engine load is smaller than that of methane which results in a higher indicated efficiency. The richness of the hydrogen-air mixture has a great influence on the heat transfer process in contrast to the in-cylinder mass in the case of methane. (orig.)

  8. Engineering: issues, challenges and opportunities for development

    CSIR Research Space (South Africa)

    Wall, K

    2010-10-01

    Full Text Available to contribute to greater international understanding of the issues, challenges and opportunities facing engineering, with a particular focus on contributions of our discipline to sustainable development. The Report, one of the most cost-effective reports UNESCO...

  9. Hypersonic Engine Leading Edge Experiments in a High Heat Flux, Supersonic Flow Environment

    Science.gov (United States)

    Gladden, Herbert J.; Melis, Matthew E.

    1994-01-01

    A major concern in advancing the state-of-the-art technologies for hypersonic vehicles is the development of an aeropropulsion system capable of withstanding the sustained high thermal loads expected during hypersonic flight. Three aerothermal load related concerns are the boundary layer transition from laminar to turbulent flow, articulating panel seals in high temperature environments, and strut (or cowl) leading edges with shock-on-shock interactions. A multidisciplinary approach is required to address these technical concerns. A hydrogen/oxygen rocket engine heat source has been developed at the NASA Lewis Research Center as one element in a series of facilities at national laboratories designed to experimentally evaluate the heat transfer and structural response of the strut (or cowl) leading edge. A recent experimental program conducted in this facility is discussed and related to cooling technology capability. The specific objective of the experiment discussed is to evaluate the erosion and oxidation characteristics of a coating on a cowl leading edge (or strut leading edge) in a supersonic, high heat flux environment. Heat transfer analyses of a similar leading edge concept cooled with gaseous hydrogen is included to demonstrate the complexity of the problem resulting from plastic deformation of the structures. Macro-photographic data from a coated leading edge model show progressive degradation over several thermal cycles at aerothermal conditions representative of high Mach number flight.

  10. Malone-brayton cycle engine/heat pump

    Science.gov (United States)

    Gilmour, Thomas A.

    1994-07-01

    A machine, such as a heat pump, and having an all liquid heat exchange fluid, operates over a more nearly ideal thermodynamic cycle by adjustment of the proportionality of the volumetric capacities of a compressor and an expander to approximate the proportionality of the densities of the liquid heat exchange fluid at the chosen working pressures. Preferred forms of a unit including both the compressor and the expander on a common shaft employs difference in axial lengths of rotary pumps of the gear or vane type to achieve the adjustment of volumetric capacity. Adjustment of the heat pump system for differing heat sink conditions preferably employs variable compression ratio pumps.

  11. New trends in nuclear power engineering development

    International Nuclear Information System (INIS)

    Krasin, A.K.

    1974-01-01

    The specific features are considered of three designs of nuclear power plants with fast reactors: three-circuit nuclear power plant with liquid sodium as primary and secondary coolant, in the third circuit water vapor being used as turbine working medium, dual cycle nuclear power plant with pressurized helium as primary coolant and water vapor as turbine working medium, direct cycle nuclear power plant with a dissociating gas (nitrogen tetroxide N 2 O 4 ) as reactor coolant and turbine working medium. The version of the direct cycle nuclear power plant with dissociating N 2 O 4 was proposed and being developed by the Institute of Nuclear Engineering of the Academy of Sciencies of the BSSR. The thermal and physical properties of the dissociating gas allow a high-power-density reactor core to be used with a hard neutron spectra resulting in a high breeding ratio and a short doubling time. The pressure range from 150 to 170 bar was proven for this coolant under laboratory conditions and structural materials were chosen that ensure all the components of the direct cycle nuclear power plant to be workable. At present it is difficult to say which of the three versions is the most advantageous. The further development of a full-scale prototypes of a commercial nuclear power plant with a fast reactor and investigation of their technical and economic parameters remain the problems of utmost importance. A possible use of nuclear reactors is shortly considered for process heat production, in ferrous metallurgy, for hydrogen and new isotope production, and for radiation chemistry as well

  12. Brownian micro-engines and refrigerators in a spatially periodic temperature field: Heat flow and performances

    International Nuclear Information System (INIS)

    Ai Baoquan; Wang Liqiu; Liu Lianggang

    2006-01-01

    We study the thermodynamic features of a thermal motor driven by temperature differences, which consists of a Brownian particle moving in a sawtooth potential with an external load. The motor can work as a heat engine or a refrigerator under different conditions. The heat flow driven by both potential and kinetic energy is considered. The former is reversible when the engine works quasistatically and the latter is always irreversible. The efficiency of the heat engine (Coefficient Of Performance (COP) of a refrigerator) can never approach Carnot efficiency (COP)

  13. Performance analysis of irreversible molten carbonate fuel cell – Braysson heat engine with ecological objective approach

    International Nuclear Information System (INIS)

    Açıkkalp, Emin

    2017-01-01

    Highlights: • An irreversible MCFC - Braysson heat engine is considered. • Its performance is investigated with ecological approach. • A new ecological criteria are presented called as modified ecological function. • Result are obtained numerically and discussed. - Abstract: An irreversible hybrid molten carbonate fuel cell-Braysson heat engine is taken into account. Basic thermodynamics parameters including power output, efficiency and exergy destruction rate are considered. In addition ecological function and new criteria, which is based on ecological function, for heat engines called as modified ecological function is suggested. Optimum conditions for mentioned parameters above are determined. Numerical results are obtained and plotted. Finally, results are discussed.

  14. Effects of irreversibility and economics on the performance of a heat engine

    International Nuclear Information System (INIS)

    Ibrahim, O.M.; Klein, S.A.; Mitchell, J.W.

    1992-01-01

    In this paper, optimization of the power output of an internally irreversible heat engine is considered for finite capacitance rates of the external fluid streams. The method of Lagrange multipliers is used to solve for working fluid temperatures which yield maximum power. Analytical expressions for the maximum power and the cycle efficiency at miximum power are obtained. The effects of irreversibility and economics on the performance of a heat engine are investigated. A relationship between the maximum power point and economically optimum design is identified. It is demonstrated that, with certain reasonable economic assumptions, the maximum power point of a heat engine corresponds to a point of minimum life-cycle costs

  15. Design and preliminary test of heat isulated pistons for a diesel engine. Dieselmoottorin laempoeeristetyn maennaen suunnittelu ja esikokeet

    Energy Technology Data Exchange (ETDEWEB)

    Kojonen, M.; Pitkaenen, J.; Kleimola, M.

    1989-01-01

    This report describes the ceramic heat insulation of the combustion chamber of high speed diesel engines and results of tests carried out in one cylinder of a four-cylinder engine with two different heat insulated experimental pistons. The work is part of the research programme called 'Ceramic applications in mechanical engineering'. The research work is being done at Helsinki University of Technology in the Internal Combustion Engine Laboratory and is financed mainly by the Technology Development Centre TEKES. Valmet Oy Linnavuori Works has contributed to the work by supplying the test engine for the research. In the short literature review presented first. advantages of the combustion chamber insulation and design solutions for heat flow prevention are described. In the experimental part of the research two different experimental pistons with ceramic combustion chamber were designed for the Valmet 411 DSJ diesel engine with direct injection. One of the pistons was furnished with a steel piston head, which was fastened to the aluminium piston body. The ceramic combustion chamber bowl was inserted into the steel head. The other piston was developed from Kymenite cast iron, which made it possible to insert the piston bowl direct into the piston body. The aim of the experiments was to clarify the function ability and the necessary clearances of the piston constructions and to indicate the insulation ability of the combustion chamber by means of the temperature measurements of the cylinder liner, cylinder head and exhaust gas temperature.

  16. Theoretical investigation of heat balance in direct injection (DI) diesel engines for neat diesel fuel and gasoline fumigation

    International Nuclear Information System (INIS)

    Durgun, O.; Sahin, Z.

    2009-01-01

    The main purpose of the presented study is to evaluate energy balance theoretically in direct injection (DI) diesel engines at different conditions. To analyze energy balance, a zero-dimensional multi-zone thermodynamic model has been developed and used. In this thermodynamic model, zero-dimensional intake and exhaust approximations given by Durgun, zero-dimensional compression and expansion model given by Heywood and quasi-dimensional phenomenological combustion model developed by Shahed and then improved Ottikkutti have been used and developed with new approximations and assumptions. By using the developed model, complete diesel engine cycle, engine performance parameters and exhaust emissions can be determined easily. Also, by using this model energy balance can be analyzed for neat diesel fuel and for light fuel fumigation easily. In the presented study, heat balance has been investigated theoretically for three different engines and various numerical applications have been conducted. In the numerical applications two different turbocharged DI diesel engines and a naturally aspirated DI diesel engine have been used. From these numerical applications, it is determined that, what portion of available fuel energy is converted to useful work, what amount of fuel energy is lost by exhaust gases or lost by heat transfer. In addition, heat balance has been analyzed for gasoline fumigation and some numerical results have been given. Brake effective power and brake specific fuel consumption increase and brake effective efficiency decreases for gasoline fumigation for turbocharged diesel engines used in numerical applications. Combustion duration increases with increasing fumigation ratio and thus heat transfer to the walls increases. Because exhaust temperature increases, exhaust losses also increases for fumigation case

  17. 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...

  18. Thin film heat flux sensor for Space Shuttle Main Engine turbine environment

    Science.gov (United States)

    Will, Herbert

    1991-01-01

    The Space Shuttle Main Engine (SSME) turbine environment stresses engine components to their design limits and beyond. The extremely high temperatures and rapid temperature cycling can easily cause parts to fail if they are not properly designed. Thin film heat flux sensors can provide heat loading information with almost no disturbance of gas flows or of the blade. These sensors can provide steady state and transient heat flux information. A thin film heat flux sensor is described which makes it easier to measure small temperature differences across very thin insulating layers.

  19. Assessment and Development of Engineering Design Processes

    DEFF Research Database (Denmark)

    Ulrikkeholm, Jeppe Bjerrum

    , the engineering companies need to have efficient engineering design processes in place, so they can design customised product variants faster and more efficiently. It is however not an easy task to model and develop such processes. To conduct engineering design is often a highly iterative, illdefined and complex...... the process can be fully understood and eventually improved. Taking its starting point in this proposition, the outcome of the research is an operational 5-phased procedure for assessing and developing engineering design processes through integrated modelling of product and process, designated IPPM......, and eventually the results are discussed, overall conclusions are made and future research is proposed. The results produced throughout the research project are developed in close collaboration with the Marine Low Speed business unit within the company MAN Diesel & Turbo. The business unit is the world market...

  20. Design and evaluation of fluidized bed heat recovery for diesel engine systems

    Science.gov (United States)

    Hamm, J. R.; Newby, R. A.; Vidt, E. J.; Lippert, T. E.

    1985-01-01

    The potential of utilizing fluidized bed heat exchangers in place of conventional counter-flow heat exchangers for heat recovery from adiabatic diesel engine exhaust gas streams was studied. Fluidized bed heat recovery systems were evaluated in three different heavy duty transport applications: (1) heavy duty diesel truck; (2) diesel locomotives; and (3) diesel marine pushboat. The three applications are characterized by differences in overall power output and annual utilization. For each application, the exhaust gas source is a turbocharged-adiabatic diesel core. Representative subposed exhaust gas heat utilization power cycles were selected for conceptual design efforts including design layouts and performance estimates for the fluidized bed heat recovery heat exchangers. The selected power cycles were: organic rankine with RC-1 working fluid, turbocompound power turbine with steam injection, and stirling engine. Fuel economy improvement predictions are used in conjunction with capital cost estimates and fuel price data to determine payback times for the various cases.

  1. The second law of thermodynamics and quantum heat engines: Is the law strictly enforced?

    Science.gov (United States)

    Keefe, Peter D.

    2010-01-01

    A quantum heat engine is a construct having a working medium which is cyclically processed through a pair of control variables of state involving a Bose-Einstein condensation (BEC) in which a heat input is converted into a work output. Of interest is a first species of quantum heat engine in which the working medium is macroscopic in the sense the size scale is sufficiently large that the BEC is not volumetrically coherent. In this first species of quantum heat engine, near Carnot efficiencies may be possible. Of particular interest is a second species of quantum heat engine in which the working medium is mesoscopic in the sense that the size scale is sufficiently small that the BEC is volumetrically coherent. In this second species of quantum heat engine, the resulting in-process non-equilibrium condition affects the finally arrived at control variables of state such that Carnot efficiencies and beyond may be possible. A Type I superconductor is used to model the first and second species of quantum heat engine.

  2. Development of an engineering model for ferromagnetic shape memory alloys

    International Nuclear Information System (INIS)

    Tani, Yoshiaki; Todaka, Takashi; Enokizono, Masato

    2008-01-01

    This paper presents a relationship among stress, temperature and magnetic properties of a ferromagnetic shape memory alloy. In order to derive an engineering model of ferromagnetic shape memory alloys, we have developed a measuring system of the relationship among stress, temperature and magnetic properties. The samples used in this measurement are Fe68-Ni10-Cr9-Mn7-Si6 wt% ferromagnetic shape memory alloy. They are thin ribbons made by rapid cooling in air. In the measurement, the ribbon sample is inserted into a sample holder winding consisting of the B-coil and compensation coils, and magnetized in an open solenoid coil. The ribbon is stressed with attachment weights and heated with a heating wire. The specific susceptibility was increased by applying tension, and slightly increased by heating below the Curie temperature

  3. Active solar heating industry development study

    International Nuclear Information System (INIS)

    1995-01-01

    Despite the fact that solar water heating systems are technologically viable and commercially available, this Energy Technology Support Unit report shows that there is no established market in the United Kingdom. The Solar Trade Association (STA) has undertaken an Active Solar Heating Industry Development Study which is reported here. The data is derived from a questionnaire survey completed by companies, organizations and individuals operating within the industry. Information was also gathered from utility companies, and STAs elsewhere in Europe. Barriers which need to be overcome include lack of public awareness, especially in the construction industry, lack of capital investment and other financial disincentives, little or no government support, and lack of organization and quality monitoring and assurance within the industry itself. (UK)

  4. Biomedical engineering for health research and development.

    Science.gov (United States)

    Zhang, X-Y

    2015-01-01

    Biomedical engineering is a new area of research in medicine and biology, providing new concepts and designs for the diagnosis, treatment and prevention of various diseases. There are several types of biomedical engineering, such as tissue, genetic, neural and stem cells, as well as chemical and clinical engineering for health care. Many electronic and magnetic methods and equipments are used for the biomedical engineering such as Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI) scans, Electroencephalography (EEG), Ultrasound and regenerative medicine and stem cell cultures, preparations of artificial cells and organs, such as pancreas, urinary bladders, liver cells, and fibroblasts cells of foreskin and others. The principle of tissue engineering is described with various types of cells used for tissue engineering purposes. The use of several medical devices and bionics are mentioned with scaffold, cells and tissue cultures and various materials are used for biomedical engineering. The use of biomedical engineering methods is very important for the human health, and research and development of diseases. The bioreactors and preparations of artificial cells or tissues and organs are described here.

  5. Comparing Two Definitions of Work for a Biological Quantum Heat Engine

    International Nuclear Information System (INIS)

    Xu You-Yang; Zhao Shun-Cai; Liu Juan

    2015-01-01

    Systems of photosynthetic reaction centres have been modelled as heat engines, while it has also been reported that the efficiency and power of such heat engines can be enhanced by quantum interference — a trait that has attracted much interest. We compare two definitions of the work of such a photosynthetic heat engine, i.e. definition A used by Weimer et al. and B by Dorfman et al. We also introduce a coherent interaction between donor and acceptor (CIDA) to demonstrate a reversible energy transport. We show that these two definitions of work can impart contradictory results, that is, CIDA enhances the power and efficiency of the photosynthetic heat engine with definition B but not with A. Additionally, we find that both reversible and irreversible excitation-energy transport can be described with definition A, but definition B can only model irreversible transport. As a result, we conclude that definition A is more suitable for photosynthetic systems than definition B. (paper)

  6. A combined thermodynamic cycle based on methanol dissociation for IC (internal combustion) engine exhaust heat recovery

    International Nuclear Information System (INIS)

    Fu, Jianqin; Liu, Jingping; Xu, Zhengxin; Ren, Chengqin; Deng, Banglin

    2013-01-01

    In this paper, a novel approach for exhaust heat recovery was proposed to improve IC (internal combustion) engine fuel efficiency and also to achieve the goal for direct usage of methanol as IC engine fuel. An open organic Rankine cycle system using methanol as working medium is coupled to IC engine exhaust pipe for exhaust heat recovery. In the bottom cycle, the working medium first undergoes dissociation and expansion processes, and is then directed back to IC engine as fuel. As the external bottom cycle and the IC engine main cycle are combined together, this scheme forms a combined thermodynamic cycle. Then, this concept was applied to a turbocharged engine, and the corresponding simulation models were built for both of the external bottom cycle and the IC engine main cycle. On this basis, the energy saving potential of this combined cycle was estimated by parametric analyses. Compared to the methanol vapor engine, IC engine in-cylinder efficiency has an increase of 1.4–2.1 percentage points under full load conditions, while the external bottom cycle can increase the fuel efficiency by 3.9–5.2 percentage points at the working pressure of 30 bar. The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points. - Highlights: • A combined thermodynamic cycle using methanol as working medium for IC engine exhaust heat recovery is proposed. • The external bottom cycle of exhaust heat recovery and IC engine working cycle are combined together. • IC engine fuel efficiency could be improved from both in-cylinder working cycle and external bottom cycle. • The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points at full load

  7. Overview of heat transfer and fluid flow problem areas encountered in Stirling engine modeling

    Science.gov (United States)

    Tew, Roy C., Jr.

    1988-01-01

    NASA Lewis Research Center has been managing Stirling engine development programs for over a decade. In addition to contractual programs, this work has included in-house engine testing and development of engine computer models. Attempts to validate Stirling engine computer models with test data have demonstrated that engine thermodynamic losses need better characterization. Various Stirling engine thermodynamic losses and efforts that are underway to characterize these losses are discussed.

  8. Development of nuclear rocket engine technology

    International Nuclear Information System (INIS)

    Gunn, S.V.

    1989-01-01

    Research sponsored by the Atomic Energy Commission, the USAF, and NASA (later on) in the area of nuclear rocket propulsion is discussed. It was found that a graphite reactor, loaded with highly concentrated Uranium 235, can be used to heat high pressure liquid hydrogen to temperatures of about 4500 R, and to expand the hydrogen through a high expansion ratio rocket nozzle assembly. The results of 20 reactor tests conducted at the Nevada Test Site between July 1959 and June 1969 are analyzed. On the basis of these results, the feasibility of solid graphite reactor/nuclear rocket engines is revealed. It is maintained that this technology will support future space propulsion requirements, using liquid hydrogen as the propellant, for thrust requirements ranging from 25,000 lbs to 250,000 lbs, with vacuum specific impulses of at least 850 sec and with full engine throttle capability. 12 refs

  9. On the thermodynamics of waste heat recovery from internal combustion engine exhaust gas

    Science.gov (United States)

    Meisner, G. P.

    2013-03-01

    The ideal internal combustion (IC) engine (Otto Cycle) efficiency ηIC = 1-(1/r)(γ - 1) is only a function of engine compression ratio r =Vmax/Vmin and exhaust gas specific heat ratio γ = cP/cV. Typically r = 8, γ = 1.4, and ηIC = 56%. Unlike the Carnot Cycle where ηCarnot = 1-(TC/TH) for a heat engine operating between hot and cold heat reservoirs at TH and TC, respectively, ηIC is not a function of the exhaust gas temperature. Instead, the exhaust gas temperature depends only on the intake gas temperature (ambient), r, γ, cV, and the combustion energy. The ejected exhaust gas heat is thermally decoupled from the IC engine and conveyed via the exhaust system (manifold, pipe, muffler, etc.) to ambient, and the exhaust system is simply a heat engine that does no useful work. The maximum fraction of fuel energy that can be extracted from the exhaust gas stream as useful work is (1-ηIC) × ηCarnot = 32% for TH = 850 K (exhaust) and TC = 370 K (coolant). This waste heat can be recovered using a heat engine such as a thermoelectric generator (TEG) with ηTEG> 0 in the exhaust system. A combined IC engine and TEG system can generate net useful work from the exhaust gas waste heat with efficiency ηWH = (1-ηIC) × ηCarnot ×ηTEG , and this will increase the overall fuel efficiency of the total system. Recent improvements in TEGs yield ηTEG values approaching 15% giving a potential total waste heat conversion efficiency of ηWH = 4.6%, which translates into a fuel economy improvement approaching 5%. This work is supported by the US DOE under DE-EE0005432.

  10. Improving the engineering strength of heat strengthened glass

    NARCIS (Netherlands)

    Veer, F.A.; Rodichev, YM

    2016-01-01

    Although glass is increasingly used as a structural material, glass is not produced to strength standards, like steel and concrete. Of the three types of glass: annealed, heat strengthened and fully tempered, only heat strengthened glass has the properties to function as a safe structural material.

  11. Engineering economic assessment of residential wood heating in NY

    Science.gov (United States)

    We provide insight into the recent resurgence in residential wood heating in New York by: (i) examining the lifetime costs of outdoor wood hydronic heaters (OWHHs) and other whole-house residential wood heat devices,(ii) comparing these lifetime costs with those of competing tech...

  12. A review on opportunities for the development of heat pump drying systems in South Africa

    Directory of Open Access Journals (Sweden)

    Thomas Kivevele

    2014-05-01

    Full Text Available Recently, it has been discovered that heat pump drying is an efficient method of drying for drying industries. Heat pumps deliver more heat during the drying process than the work input to the compressor. Heat pump drying is a more advanced method than the traditional South African industrial and agricultural drying methods, such as direct/indirect sunlight, wood burning, fossil fuel burning, electrical heating and diesel engine heating. Heat pump dryers provide high energy efficiency with controllable temperature, air flow and air humidity and have significant energy-saving potential. In the last decade the market for heat pump systems for water heating and space cooling/heating has grown in South Africa, but the development of heat pumps for industrial and agricultural drying is very slow. As a result of high increases in fossil fuel prices and electricity in South Africa, as well as the problem of CO2 emissions, green energy, energy saving and energy efficiency are imperative. The development of heat pump drying systems in South Africa is an efficient way to solve energy problems in drying applications as this technology is still in its infancy. We review studies on heat pump drying and compare the methods therein with the most common methods of drying in South Africa.

  13. Integration of a wood pellet burner and a Stirling engine to produce residential heat and power

    International Nuclear Information System (INIS)

    Cardozo, Evelyn; Erlich, Catharina; Malmquist, Anders; Alejo, Lucio

    2014-01-01

    The integration a Stirling engine with a pellet burner is a promising alternative to produce heat and power for residential use. In this context, this study is focused on the experimental evaluation of the integration of a 20 kW th wood pellet burner and a 1 kW e Stirling engine. The thermal power not absorbed by the engine is used to produce hot water. The evaluation highlights the effects of pellet type, combustion chamber length and cycling operation on the Stirling engine temperatures and thermal power absorbed. The results show that the position of the Stirling engine is highly relevant in order to utilize as much as possible of the radiative heat from the burner. Within this study, only a 5 cm distance change between the Stirling engine and the pellet burner could result in an increase of almost 100 °C in the hot side of the engine. However, at a larger distance, the temperature of the hot side is almost unchanged suggesting dominating convective heat transfer from the hot flue gas. Ash accumulation decreases the temperature of the hot side of the engine after some cycles of operation when a commercial pellet burner is integrated. The temperature ratio, which is the relation between the minimum and maximum temperatures of the engine, decreases when using Ø8 mm wood pellets in comparison to Ø6 mm pellets due to higher measured temperatures on the hot side of the engine. Therefore, the amount of heat supplied to the engine is increased for Ø8 mm wood pellets. The effectiveness of the engine regenerator is increased at higher pressures. The relation between temperature of the hot side end and thermal power absorbed by the Stirling engine is nearly linear between 500 °C and 660 °C. Higher pressure inside the Stirling engine has a positive effect on the thermal power output. Both the chemical and thermal losses increase somewhat when integrating a Stirling engine in comparison to a stand-alone boiler for only heat production. The overall efficiency

  14. 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.

  15. Performance optimum analysis of an irreversible molten carbonate fuel cell–Stirling heat engine hybrid system

    International Nuclear Information System (INIS)

    Chen, Liwei; Zhang, Houcheng; Gao, Songhua; Yan, Huixian

    2014-01-01

    A new hybrid system mainly consists of a molten carbonate fuel cell (MCFC) and a Stirling heat engine is established, where the Stirling heat engine is driven by the high-quality waste heat generated in the MCFC. Based on the electrochemistry and non-equilibrium thermodynamics, analytical expressions for the efficiency and power output of the hybrid system are derived by taking various irreversible losses into account. It shows that the performance of the MCFC can be greatly enhanced by coupling a Stirling heat engine to further convert the waste heat for power generation. By employing numerical calculations, not only the influences of multiple irreversible losses on the performance of the hybrid system are analyzed, but also the impacts of some operating conditions such as the operating temperature, input gas compositions and operating pressure on the performance of the hybrid system are also discussed. The investigation method in the present paper is feasible for some other similar energy conversion systems as well. - Highlights: • A model of MCFC–Stirling heat engine hybrid system is established. • Analytical expressions for the efficiency and power output are derived. • MCFC performance can be greatly enhanced by coupling a Stirling heat engine. • Effects of some operating conditions on the performance are discussed. • Optimum operation regions are subdivided by multi-objective optimization method

  16. Heat exchanger design for hot air ericsson-brayton piston engine

    Directory of Open Access Journals (Sweden)

    Ďurčanský P.

    2014-03-01

    Full Text Available One of the solutions without negative consequences for the increasing energy consumption in the world may be use of alternative energy sources in micro-cogeneration. Currently it is looking for different solutions and there are many possible ways. Cogeneration is known for long time and is widely used. But the installations are often large and the installed output is more suitable for cities or industry companies. When we will speak about decentralization, the small machines have to be used. The article deals with the principle of hot-air engines, their use in combined heat and electricity production from biomass and with heat exchangers as primary energy transforming element. In the article is hot air engine presented as a heat engine that allows the conversion of heat into mechanical energy while heat supply can be external. In the contribution are compared cycles of hot-air engine. Then are compared suitable heat exchangers for use with hot air Ericsson-Brayton engine. In the final part is proposal of heat exchanger for use in closed Ericsson-Brayton cycle.

  17. Heat exchanger design for hot air ericsson-brayton piston engine

    Science.gov (United States)

    Ďurčanský, P.; Lenhard, R.; Jandačka, J.

    2014-03-01

    One of the solutions without negative consequences for the increasing energy consumption in the world may be use of alternative energy sources in micro-cogeneration. Currently it is looking for different solutions and there are many possible ways. Cogeneration is known for long time and is widely used. But the installations are often large and the installed output is more suitable for cities or industry companies. When we will speak about decentralization, the small machines have to be used. The article deals with the principle of hot-air engines, their use in combined heat and electricity production from biomass and with heat exchangers as primary energy transforming element. In the article is hot air engine presented as a heat engine that allows the conversion of heat into mechanical energy while heat supply can be external. In the contribution are compared cycles of hot-air engine. Then are compared suitable heat exchangers for use with hot air Ericsson-Brayton engine. In the final part is proposal of heat exchanger for use in closed Ericsson-Brayton cycle.

  18. Systems engineering real estate development projects

    Science.gov (United States)

    Gusakova, Elena; Titarenko, Boris; Stepanov, Vitaliy

    2017-10-01

    In recent years, real estate development has accumulated a wealth of experience in implementing major projects, which requires comprehension and systematization. The scientific instrument of system engineering is studied in the article and is substantively interpreted with reference to real estate development projects. The most perspective approaches and models are substantiated, allowing strategically to plan the life cycle of the project as a whole, and also to solve the engineering butt problems of the project. The relevance of further scientific studies of regularities and specifics of the life cycle of real estate development projects conducted at the Moscow State University of Economics and Management at the ISTA department is shown.

  19. NNC's engineering development centre at Risley

    International Nuclear Information System (INIS)

    Garnsey, R.

    1994-01-01

    NNC's Engineering Development Centre (EDC) provides specialist engineering, manufacturing and development support to customers. EDC is located at Risley, near Warrington, but its operation are closely integrated into the Company's overall business activities based at its headquarters in Knutsford, Cheshire, fifteen miles away. EDC's facilities and expertise were originally developed to support the UK's nuclear power station construction programme. However, EDC professionals have since applied their specialist expertise to the benefit of new customers in line with the Company's diversification and a large and growing proportion of work is now in support of the defence and process industries. (author)

  20. Designing a solar powered Stirling heat engine based on multiple criteria: Maximized thermal efficiency and power

    International Nuclear Information System (INIS)

    Ahmadi, Mohammad Hossein; Sayyaadi, Hoseyn; Dehghani, Saeed; Hosseinzade, Hadi

    2013-01-01

    Highlights: • Thermodynamic model of a solar-dish Stirling engine was presented. • Thermal efficiency and output power of the engine were simultaneously maximized. • A final optimal solution was selected using several decision-making methods. • An optimal solution with least deviation from the ideal design was obtained. • Optimal solutions showed high sensitivity against variation of system parameters. - Abstract: A solar-powered high temperature differential Stirling engine was considered for optimization using multiple criteria. A thermal model was developed so that the output power and thermal efficiency of the solar Stirling system with finite rate of heat transfer, regenerative heat loss, conductive thermal bridging loss, finite regeneration process time and imperfect performance of the dish collector could be obtained. The output power and overall thermal efficiency were considered for simultaneous maximization. Multi-objective evolutionary algorithms (MOEAs) based on the NSGA-II algorithm were employed while the solar absorber temperature and the highest and lowest temperatures of the working fluid were considered the decision variables. The Pareto optimal frontier was obtained and a final optimal solution was also selected using various decision-making methods including the fuzzy Bellman–Zadeh, LINMAP and TOPSIS. It was found that multi-objective optimization could yield results with a relatively low deviation from the ideal solution in comparison to the conventional single objective approach. Furthermore, it was shown that, if the weight of thermal efficiency as one of the objective functions is considered to be greater than weight of the power objective, lower absorber temperature and low temperature ratio should be considered in the design of the Stirling engine

  1. Finite-Time Thermoeconomic Optimization of a Solar-Driven Heat Engine Model

    Directory of Open Access Journals (Sweden)

    Fernando Angulo-Brown

    2011-01-01

    Full Text Available In the present paper, the thermoeconomic optimization of an irreversible solar-driven heat engine model has been carried out by using finite-time/finite-size thermodynamic theory. In our study we take into account losses due to heat transfer across finite time temperature differences, heat leakage between thermal reservoirs and internal irreversibilities in terms of a parameter which comes from the Clausius inequality. In the considered heat engine model, the heat transfer from the hot reservoir to the working fluid is assumed to be Dulong-Petit type and the heat transfer to the cold reservoir is assumed of the Newtonian type. In this work, the optimum performance and two design parameters have been investigated under two objective functions: the power output per unit total cost and the ecological function per unit total cost. The effects of the technical and economical parameters on the thermoeconomic performance have been also discussed under the aforementioned two criteria of performance.

  2. Evaporation and condensation devices for passive heat removal systems in nuclear power engineering

    International Nuclear Information System (INIS)

    Gershuni, A.N.; Pis'mennyj, E.N.; Nishchik, A.P.

    2016-01-01

    The paper justifies advantages of evaporation and condensation heat transfer devices as means of passive heat removal and thermal shielding in nuclear power engineering. The main thermophysical factors that limit heat transfer capacity of evaporation and condensation systems have been examined in the research. The results of experimental studies of heat engineering properties of elongated (8-m) vertically oriented evaporation and condensation devices (two-phase thermosyphons), which showed a high enough heat transfer capacity, as well as stability and reliability both in steady state and in start-up modes, are provided. The paper presents the examples of schematic designs of evaporation and condensation systems for passive heat removal and thermal shielding in application to nuclear power equipment

  3. Waste heat recovery system for recapturing energy after engine aftertreatment systems

    Science.gov (United States)

    Ernst, Timothy C.; Nelson, Christopher R.

    2014-06-17

    The disclosure provides a waste heat recovery (WHR) system including a Rankine cycle (RC) subsystem for converting heat of exhaust gas from an internal combustion engine, and an internal combustion engine including the same. The WHR system includes an exhaust gas heat exchanger that is fluidly coupled downstream of an exhaust aftertreatment system and is adapted to transfer heat from the exhaust gas to a working fluid of the RC subsystem. An energy conversion device is fluidly coupled to the exhaust gas heat exchanger and is adapted to receive the vaporized working fluid and convert the energy of the transferred heat. The WHR system includes a control module adapted to control at least one parameter of the RC subsystem based on a detected aftertreatment event of a predetermined thermal management strategy of the aftertreatment system.

  4. Building an Understanding of Heat Transfer Concepts in Undergraduate Chemical Engineering Courses

    Science.gov (United States)

    Nottis, Katharyn E. K.; Prince, Michael J.; Vigeant, Margot A.

    2010-01-01

    Understanding the distinctions among heat, energy and temperature can be difficult for students at all levels of instruction, including those in engineering. Misconceptions about heat transfer have been found to persist, even after students successfully complete relevant coursework. New instructional methods are needed to address these…

  5. The Amount of Regenerated Heat Inside the Regenerator of a Stirling Engine

    Directory of Open Access Journals (Sweden)

    J. Škorpík

    2008-01-01

    Full Text Available The paper deals with analytical computing of the regenerated heat inside the regenerator of a Stirling engine. The total sum of the regenerated heat is constructed as a function of the crank angle in the case of Schmidt’s idealization. 

  6. Sales promotion and utilization of fuel. Engineering service of the heat industry for industrial companies

    Energy Technology Data Exchange (ETDEWEB)

    Schoen, E. (Ruhrgas A.G., Essen (Germany, F.R.). Abt. E-F)

    1978-01-01

    The contribution illustrates, from the industrial viewpoint, how one may produce process heat rationally and make optimum use of it using natural gas and how competing fuels can be supplanted. The heat economy engineering activities of a modern gas supply undertaking and a few practical examples to improve the industrial produce structure are shown.

  7. Fuel effects on knock, heat releases and CARS temperatures in a spark ignition engine

    NARCIS (Netherlands)

    Kalghatgi, G.T.; Golombok, M.; Snowdon, P.

    1995-01-01

    Net heat release, knock characteristics and temperature were derived from in-cylinder pressure and end-gas CARS measurements for different fuels in a single-cylinder engine. The maximum net heat release rate resulting from the final phase of autoignition is closely associated with knock intensity.

  8. Engineering software development with HyperCard

    Science.gov (United States)

    Darko, Robert J.

    1990-01-01

    The successful and unsuccessful techniques used in the development of software using HyperCard are described. The viability of the HyperCard for engineering is evaluated and the future use of HyperCard by this particular group of developers is discussed.

  9. Software Engineering Principles for Courseware Development.

    Science.gov (United States)

    Magel, Kenneth

    1980-01-01

    Courseware (computer based curriculum materials) development should follow the lessons learned by software engineers. The most important of 28 principles of software development presented here include a stress on human readability, the importance of early planning and analysis, the need for independent evaluation, and the need to be flexible.…

  10. Quantum lubrication: Suppression of friction in a first-principles four-stroke heat engine

    Science.gov (United States)

    Feldmann, Tova; Kosloff, Ronnie

    2006-02-01

    A quantum model of a heat engine resembling the Otto cycle is employed to explore strategies to suppress frictional losses. These losses are caused by the inability of the engine’s working medium to follow adiabatically the change in the Hamiltonian during the expansion and compression stages. By adding external noise to the engine frictional losses can be suppressed.

  11. To capabilities of heat engines with gas working medium in closed cycle

    International Nuclear Information System (INIS)

    Kotov, V.M.; Tikhomirov, L.N.; Rajkhanov, N.A.; Kotov, S.V.

    2003-01-01

    The effort gives analysis of performance of engines and heat pumps with closed cycles based on use of well practiced adiabatic and isobaric processes. Advantages of theses cycles are demonstrated as compared to Stirling engines, and capabilities of their application in piston machines. (author)

  12. Offshore Wind Energy Systems Engineering Curriculum Development

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Jon G. [Univ. of Massachusetts, Amherst, MA (United States); Manwell, James F. [Univ. of Massachusetts, Amherst, MA (United States); Lackner, Matthew A. [Univ. of Massachusetts, Amherst, MA (United States)

    2012-12-31

    Utility-scale electricity produced from offshore wind farms has the potential to contribute significantly to the energy production of the United States. In order for the U.S. to rapidly develop these abundant resources, knowledgeable scientists and engineers with sound understanding of offshore wind energy systems are critical. This report summarizes the development of an upper-level engineering course in "Offshore Wind Energy Systems Engineering." This course is designed to provide students with a comprehensive knowledge of both the technical challenges of offshore wind energy and the practical regulatory, permitting, and planning aspects of developing offshore wind farms in the U.S. This course was offered on a pilot basis in 2011 at the University of Massachusetts and the National Renewable Energy Laboratory (NREL), TU Delft, and GL Garrad Hassan have reviewed its content. As summarized in this report, the course consists of 17 separate topic areas emphasizing appropriate engineering fundamentals as well as development, planning, and regulatory issues. In addition to the course summary, the report gives the details of a public Internet site where references and related course material can be obtained. This course will fill a pressing need for the education and training of the U.S. workforce in this critically important area. Fundamentally, this course will be unique due to two attributes: an emphasis on the engineering and technical aspects of offshore wind energy systems, and a focus on offshore wind energy issues specific to the United States.

  13. Experimental study on heat storage system using phase-change material in a diesel engine

    International Nuclear Information System (INIS)

    Park, Sangki; Woo, Seungchul; Shon, Jungwook; Lee, Kihyung

    2017-01-01

    Engines usually use only about 25% of the total fuel energy for power, and the rest is discarded to the cooling water and exhaust gas. Therefore, a technique for utilizing external waste heat is required to improve fuel efficiency in terms of total energy consumption. In this study, a heat storage system was built using a phase-change material in order to recover about 30% of the thermal energy wasted through engine cooling. The components of the heat storage system were divided into phase-change material, a heat exchanger, and a heat-insulating container. For each component, a phase-change material that is suitable for use in vehicles was selected based on the safety, thermal properties, and durability. As a result, a stearic acid of a fatty acid series with natural extracts was determined to be appropriate. In order to measure the reduction in engine fuel consumption, a thermal storage system designed for the actual engine was applied to realize a quick warm-up by releasing stored heat energy directly on the coolant during a cold start. This technique added about 95 calories of heat storage device warm-up time compared to the non-added state, which was reduced by about 18.1% to about 27.1%. - Highlights: • The diesel engine used phase-change material with heat storage system. • The thermal storage system designed for the actual engine. • A stearic acid of a fatty acid series was determined to be appropriate. • Applied heat storage system was reduced by about 18.1%–27.1%.

  14. Overview of HTGR heat utilization system development at JAERI

    International Nuclear Information System (INIS)

    Miyamoto, Y.; Shiozawa, S.; Ogawa, M.; Akino, N.; Shimizu, S.; Hada, K.; Inagaki, Y.; Onuki, K.; Takeda, T.; Nishihara, T.

    1998-01-01

    The Japan Atomic Energy Research Institute (JAERI) has conducted research and development of nuclear heat utilization systems of a High Temperature Gas cooled Reactor (HTGR), which are capable to meet a large amount of energy demand without significant CO 2 emission to relax the global warming issue. The High Temperature engineering Test Reactor (HTTR) with thermal output of 30 MW and outlet coolant temperature of 950 deg C, the first HTGR in Japan, is under construction on the JAERI site, and its first criticality is scheduled for mid-1998. After the reactor performance and safety demonstration tests for several years, a hydrogen production system will be connected to the HTTR. A demonstration program on hydrogen production started in January 1997, in JAERI, as a study consigned by the Science and Technology Agency. A hydrogen production system connected to the HTTR is designed to be able to produce hydrogen by steam reforming of natural gas, using nuclear heat of 10 MW from the HTTR. The safety principle and standard are investigated for the HTTR hydrogen production system. In order to confirm safety, controllability and performance of key components in the HTTR hydrogen production system, an out-of-pile test facility on the scale of approximately 1/30 of the HTTR hydrogen production system is installed. It is equipped with an electric heater as a heat source instead of the HTTR. The out-of-pile test will be performed for four years after 2001. The HTTR hydrogen production system will be demonstratively operated after 2005 at its earliest plan. Other basic studies on the hydrogen production system using thermochemical water splitting, an iodine sulphur (IS) process, and technology of distant heat transport with microencapsulated phase change material have been carried out for more effective and various uses of nuclear heat. (author)

  15. Energy Efficient Waste Heat Recovery from an Engine Exhaust System

    Science.gov (United States)

    2016-12-01

    costs for the operation of the ship. The types of boilers used in this process are specially built to have water flowing around thousands of tubes ...uneven heating of the water and metal heat exchanger, leading to damage or possible failure of the boiler . Since the merchant vessels operate at near...one of the central boiler tubes . Each of the sensors was individually adjusted to ensure that the readings were as accurate as possible to allow for

  16. Federal Funding of Engineering Research and Development, 1980-1984.

    Science.gov (United States)

    American Society of Mechanical Engineers, Washington, DC.

    Data on the sources, amounts, and trends of federal funding for engineering research and development (R&D) are presented for 1980-1984. Narrative highlights are provided for: the total federal funding obligations for engineering R&D, mechanical engineering, astronautical engineering, aeronautical engineering, chemical engineering, civil…

  17. Synchronized fusion development considering physics, materials and heat transfer

    Science.gov (United States)

    Wong, C. P. C.; Liu, Y.; Duan, X. R.; Xu, M.; Li, Q.; Feng, K. M.; Zheng, G. Y.; Li, Z. X.; Wang, X. Y.; Li, B.; Zhang, G. S.

    2017-12-01

    Significant achievements have been made in the last 60 years in the development of fusion energy with the tokamak configuration. Based on the accumulated knowledge, the world is embarking on the construction and operation of ITER (International Thermonuclear Experimental Reactor) with a production of 500 MWf fusion power and the demonstration of physics Q  =  10. ITER will demonstrate D-T burn physics for a duration of a few hundred seconds to prepare for the next long-burn or steady state nuclear testing tokamak operating at much higher neutron fluence. With the evolution into a steady state nuclear device, such as the China Fusion Engineering Test Reactor (CFETR), it is necessary to examine the boundary conditions imposed by the combined development of tokamak physics, fusion materials and fusion technology for a reactor. The development of ferritic steel alloys as the structural material suitable for use at high neutron fluence leads to the use of helium as the most likely reactor coolant. This points to the fundamental technology limitation on the removal of chamber wall maximum heat flux at around 1 MW m-2 and an average heat flux of 0.1 MW m-2 for the next test reactor. Future reactor performance will then depend on the control of spatial and temporal edge heat flux peaking in order to increase the average heat flux to the chamber wall. With these severe material and technological limitations, system studies were used to scope out a few robust steady state synchronized fusion reactor (SFR) designs. As an example, a low fusion power design at 131.6 MWf, which can satisfy steady state design requirements, would have a major radius of 5.5 m and minor radius of 1.6 m. Such a design with even more advanced structural materials like W f/W composite could allow higher performance and provide a net electrical production of 62 MWe. These can be incorporated into the CFETR program.

  18. Development of HCCI Engines for Dimethyl Ether

    DEFF Research Database (Denmark)

    Hansen, Kim Rene; Pedersen, Troels Dyhr; Schramm, Jesper

    This report has been prepared for the Danish Energy Agency. It summarizes the results of the project entitled: “Development of HCCI engines for DME”. The project has been financed by “EFP 06”. The chapters about theoretical and experimental studies have been written using the language and termino......This report has been prepared for the Danish Energy Agency. It summarizes the results of the project entitled: “Development of HCCI engines for DME”. The project has been financed by “EFP 06”. The chapters about theoretical and experimental studies have been written using the language...

  19. Electrical performances of pyroelectric bimetallic strip heat engines describing a Stirling cycle

    Science.gov (United States)

    Arnaud, A.; Boughaleb, J.; Monfray, S.; Boeuf, F.; Cugat, O.; Skotnicki, T.

    2015-12-01

    This paper deals with the analytical modeling of pyroelectric bimetallic strip heat engines. These devices are designed to exploit the snap-through of a thermo-mechanically bistable membrane to transform a part of the heat flowing through the membrane into mechanical energy and to convert it into electric energy by means of a piezoelectric layer deposited on the surface of the bistable membrane. In this paper, we describe the properties of these heat engines in the case when they complete a Stirling cycle, and we evaluate the performances (available energy, Carnot efficiency...) of these harvesters at the macro- and micro-scale.

  20. Universal Trade-Off between Power, Efficiency, and Constancy in Steady-State Heat Engines

    Science.gov (United States)

    Pietzonka, Patrick; Seifert, Udo

    2018-05-01

    Heat engines should ideally have large power output, operate close to Carnot efficiency and show constancy, i.e., exhibit only small fluctuations in this output. For steady-state heat engines, driven by a constant temperature difference between the two heat baths, we prove that out of these three requirements only two are compatible. Constancy enters quantitatively the conventional trade-off between power and efficiency. Thus, we rationalize and unify recent suggestions for overcoming this simple trade-off. Our universal bound is illustrated for a paradigmatic model of a quantum dot solar cell and for a Brownian gyrator delivering mechanical work against an external force.

  1. A quantum Otto engine with finite heat baths

    DEFF Research Database (Denmark)

    Pozas-Kerstjens, Alejandro; Brown, Eric G.; Hovhannisyan, Karen V.

    2018-01-01

    We study a driven harmonic oscillator operating an Otto cycle by strongly interacting with two thermal baths of finite size. Using the tools of Gaussian quantum mechanics, we directly simulate the dynamics of the engine as a whole, without the need to make any approximations. This allows us...... to understand the non-equilibrium thermodynamics of the engine not only from the perspective of the working medium, but also as it is seen from the thermal baths' standpoint. For sufficiently large baths, our engine is capable of running a number of perfect cycles, delivering finite power while operating very...... close to maximal efficiency. Thereafter, having traversed the baths, the perturbations created by the interaction abruptly deteriorate the engine's performance. Weadditionally study the correlations generated in the system, and, in particular, we find a direct connection between the build up of bath...

  2. Optimal design of Stirling heat engine using an advanced ...

    Indian Academy of Sciences (India)

    R V Rao

    The comparisons of the proposed algorithm are made with those obtained by using the decision-making methods like linear ... cooling water and had improved the thermal efficiency of ... integrated system of a free-piston Stirling engine and an.

  3. Intermediate temperature heat release in an HCCI engine fueled by ethanol/n-heptane mixtures: An experimental and modeling study

    KAUST Repository

    Vuilleumier, David

    2014-03-01

    This study examines intermediate temperature heat release (ITHR) in homogeneous charge compression ignition (HCCI) engines using blends of ethanol and n-heptane. Experiments were performed over the range of 0-50% n-heptane liquid volume fractions, at equivalence ratios 0.4 and 0.5, and intake pressures from 1.4bar to 2.2bar. ITHR was induced in the mixtures containing predominantly ethanol through the addition of small amounts of n-heptane. After a critical threshold, additional n-heptane content yielded low temperature heat release (LTHR). A method for quantifying the amount of heat released during ITHR was developed by examining the second derivative of heat release, and this method was then used to identify trends in the engine data. The combustion process inside the engine was modeled using a single-zone HCCI model, and good qualitative agreement of pre-ignition pressure rise and heat release rate was found between experimental and modeling results using a detailed n-heptane/ethanol chemical kinetic model. The simulation results were used to identify the dominant reaction pathways contributing to ITHR, as well as to verify the chemical basis behind the quantification of the amount of ITHR in the experimental analysis. The dominant reaction pathways contributing to ITHR were found to be H-atom abstraction from n-heptane by OH and the addition of fuel radicals to O2. © 2013 The Combustion Institute.

  4. Intermediate temperature heat release in an HCCI engine fueled by ethanol/n-heptane mixtures: An experimental and modeling study

    KAUST Repository

    Vuilleumier, David; Kozarac, Darko; Mehl, Marco; Saxena, Samveg; Pitz, William J.; Dibble, Robert W.; Chen, Jyhyuan; Sarathy, Mani

    2014-01-01

    This study examines intermediate temperature heat release (ITHR) in homogeneous charge compression ignition (HCCI) engines using blends of ethanol and n-heptane. Experiments were performed over the range of 0-50% n-heptane liquid volume fractions, at equivalence ratios 0.4 and 0.5, and intake pressures from 1.4bar to 2.2bar. ITHR was induced in the mixtures containing predominantly ethanol through the addition of small amounts of n-heptane. After a critical threshold, additional n-heptane content yielded low temperature heat release (LTHR). A method for quantifying the amount of heat released during ITHR was developed by examining the second derivative of heat release, and this method was then used to identify trends in the engine data. The combustion process inside the engine was modeled using a single-zone HCCI model, and good qualitative agreement of pre-ignition pressure rise and heat release rate was found between experimental and modeling results using a detailed n-heptane/ethanol chemical kinetic model. The simulation results were used to identify the dominant reaction pathways contributing to ITHR, as well as to verify the chemical basis behind the quantification of the amount of ITHR in the experimental analysis. The dominant reaction pathways contributing to ITHR were found to be H-atom abstraction from n-heptane by OH and the addition of fuel radicals to O2. © 2013 The Combustion Institute.

  5. Numerical thermal analyses of heat exchangers for the stirling engine application

    Science.gov (United States)

    Kannapareddy, Mohan Raj

    1995-01-01

    The Regenerator, Cooler and Heater for the NASA Space Power Research Engine (SPRE) have been analyzed in detail for laminar, incompressible and oscillatory flow conditions. Each component has been analyzed independently and in detail with the regenerator being modeled as two-parallel-plates channel with a solid wall. The ends of the channel are exposed to two reservoir maintained at different temperature thus providing an axial temperature gradient along the channel. The cooler and heater components have been modeled as circular pipes with isothermal walls. Two different types of thermal boundary conditions have been investigated for the cooler and heater, namely, symmetric and asymmetric temperature inflow. In symmetric temperature inflow the flow enters the channel with the same temperature in throughout the velocity cycle whereas, in asymmetric temperature inflow the flow enters with a different temperature in each half cycle. The study was conducted over a wide range of Maximum Reynolds number (RE(max) varying from 75 to 60000, Valensi number (Va) from 2.5 to 800, and relative amplitude of fluid displacement (A(sub r) from 0.357 to 1.34. A two dimensional Finite volume method based on the SIMPLE algorithm was used to solve the governing partial differential equations. Post processing programs were developed to effectively describe the heat transfer mechanism under oscillatory flows. The computer code was validated by comparing with existing analytical solutions for oscillating flows. The thermal field have been studied with the help of temperature contour and three dimensional plots. The instantaneous friction factor, wall heat flux and heat transfer coefficient have been examined. It has been concluded that in general, the frictional factor and heat transfer coefficient are higher under oscillatory flow conditions when the Valensi number is high. Also, the thermal efficiency decreases for lower A(r) values. Further, the usual steady state definition for the

  6. Modelling the effect of injection pressure on heat release parameters and nitrogen oxides in direct injection diesel engines

    Directory of Open Access Journals (Sweden)

    Yüksek Levent

    2014-01-01

    Full Text Available Investigation and modelling the effect of injection pressure on heat release parameters and engine-out nitrogen oxides are the main aim of this study. A zero-dimensional and multi-zone cylinder model was developed for estimation of the effect of injection pressure rise on performance parameters of diesel engine. Double-Wiebe rate of heat release global model was used to describe fuel combustion. extended Zeldovich mechanism and partial equilibrium approach were used for modelling the formation of nitrogen oxides. Single cylinder, high pressure direct injection, electronically controlled, research engine bench was used for model calibration. 1000 and 1200 bars of fuel injection pressure were investigated while injection advance, injected fuel quantity and engine speed kept constant. The ignition delay of injected fuel reduced 0.4 crank angle with 1200 bars of injection pressure and similar effect observed in premixed combustion phase duration which reduced 0.2 crank angle. Rate of heat release of premixed combustion phase increased 1.75 % with 1200 bar injection pressure. Multi-zone cylinder model showed good agreement with experimental in-cylinder pressure data. Also it was seen that the NOx formation model greatly predicted the engine-out NOx emissions for both of the operation modes.

  7. Turbulence models development and engineering applications

    International Nuclear Information System (INIS)

    Groetzbach, G.; Ammann, T.; Dorr, B.; Hiltner, I.; Hofmann, S.; Kampczyk, M.; Kimhi, Y.; Seiter, C.; Woerner, M.; Alef, M.; Hennemuth, A.

    1995-01-01

    The FLUTAN code is used for analyzing the decay heat removal in new reactor concepts. The turbulence models applied in FLUTAN are improved by the development of the TURBIT code. TURBIT serves for a numerical simulation of turbulent channel flow. (orig.)

  8. Developing 3D microstructures for tissue engineering

    DEFF Research Database (Denmark)

    Mohanty, Soumyaranjan

    casting process to generate various large scale tissue engineering constructs with single pore geometry with the desired mechanical stiffness and porosity. In addition, a new technique was developed to fa bricate dual-pore scaffolds for various tissue-engineering applications where 3D printing...... materials have been developed and tested for enhancing the differentiation of hiPSC-derived hepatocytes and fabricating biodegradable scaffolds for in-vivo tissue engineering applications. Along with various scaffolds fabrication methods we finally presented an optimized study of hepatic differentiation...... of hiPSC-derived DE cells cultured for 25 days in a 3D perfusion bioreactor system with an array of 16 small-scale tissue-bioreactors with integrated dual-pore pore scaffolds and flow rates. Hepatic differentiation and functionality of hiPSC-derived hepatocytes were successfully assessed and compared...

  9. Experimentally-determined external heat loss of automotive gas turbine engine

    Science.gov (United States)

    Meng, P. R.; Wulf, R. F.

    1975-01-01

    An external heat balance was conducted on a 150 HP two-shaft automotive gas turbine engine. The engine was enclosed in a calorimeter box and the temperature change of cooling air passing through the box was measured. Cooling airflow ranges of 1.6 to 2.1 lb-per-second and 0.8 to 1.1 lb-per-second were used. The engine housing heat loss increased as the cooling airflow through the calorimeter box was increased, as would be the case in a moving automobile. The heat balance between the total energy input and the sum of shaft power output and various losses compared within 30 percent at engine idle speeds and within 7 percent at full power.

  10. Developing a Magnetocaloric Domestic Heat Pump

    DEFF Research Database (Denmark)

    Bahl, Christian R.H.

    2014-01-01

    beverage coolers, A/Cs for cars and electronics cooling. Devices for heating have not been extensively demonstrated. Here we consider a promising application of magnetocaloric heat pumps for domestic heating. The task of designing and building such a device is a multidisciplinary one encompassing materials...

  11. EU Development of High Heat Flux Components

    International Nuclear Information System (INIS)

    Linke, J.; Lorenzetto, P.; Majerus, P.; Merola, M.; Pitzer, D.; Roedig, M.

    2005-01-01

    The development of plasma facing components for next step fusion devices in Europe is strongly focused to ITER. Here a wide spectrum of different design options for the divertor target and the first wall have been investigated with tungsten, CFC, and beryllium armor. Electron beam simulation experiments have been used to determine the performance of high heat flux components under ITER specific thermal loads. Beside thermal fatigue loads with power density levels up to 20 MWm -2 , off-normal events are a serious concern for the lifetime of plasma facing components. These phenomena are expected to occur on a time scale of a few milliseconds (plasma disruptions) or several hundred milliseconds (vertical displacement events) and have been identified as a major source for the production of neutron activated metallic or tritium enriched carbon dust which is of serious importance from a safety point of view.The irradiation induced material degradation is another critical concern for future D-T-burning fusion devices. In ITER the integrated neutron fluence to the first wall and the divertor armour will remain in the order of 1 dpa and 0.7 dpa, respectively. This value is low compared to future commercial fusion reactors; nevertheless, a nonnegligible degradation of the materials has been detected, both for mechanical and thermal properties, in particular for the thermal conductivity of carbon based materials. Beside the degradation of individual material properties, the high heat flux performance of actively cooled plasma facing components has been investigated under ITER specific thermal and neutron loads

  12. The effect of heat transfer laws and thermal conductances on the local stability of an endoreversible heat engine

    International Nuclear Information System (INIS)

    Guzman-Vargas, L; Reyes-Ramirez, I; Sanchez, N

    2005-01-01

    In a recent paper (Santillan et al 2001 J. Phys. D: Appl. Phys. 34 2068-72) the local stability of a Curzon-Ahlborn-Novikov (CAN) engine with equal conductances in the coupling with thermal baths was analysed. In this work, we present a local stability analysis of an endoreversible engine operating at maximum power output, for common heat transfer laws, and for different heat conductances α and β, in the isothermal couplings of the working substance with the thermal sources T 1 and T 2 (T 1 > T 2 ). We find that the relaxation times, in the cases analysed here, are a function of α, β, the heat capacity C, T 1 and T 2 . Besides, the eigendirections in a phase portrait are also functions of τ = T 1 /T 2 and the ratio β/α. From these findings, phase portraits for the trajectories after a small perturbation over the steady-state values of internal temperatures are presented, for some significant situations. Finally, we discuss the local stability and energetic properties of the endoreversible CAN heat engine

  13. Numerical study of heat transfer and combustion in IC engine with a porous media piston region

    International Nuclear Information System (INIS)

    Zhou, Lei; Xie, Mao-Zhao; Luo, Kai Hong

    2014-01-01

    Based on superadiabatic combustion in porous medium (PM), the porous medium engine as a new combustion concept is proposed to achieve high combustion efficiency and low emissions. In this paper, an axisymmetric model with detailed chemistry and two-temperature treatment is implemented into a variant of the KIVA-3V code to simulate the working process of the PM engine. Comparisons with the same engine but without PM are conducted. Temperature evolution of the PM and its effects are discussed in detail. Key factors affecting heat transfer, combustion and emissions of the PM engine, such as porosity, the initial PM temperature and equivalence ratio, are analyzed. The results show that the characteristics of heat transfer, emissions and combustion of the PM engine are superior to the engine without PM, providing valuable support for the PM engine concept. In particular, the PM engine is shown to sustain ultra lean combustion. - Graphical abstract: In the PM engine, a PM reactor is mounted on the piston head as shown in Fig. 1 which shows the schematic diagram of the computational domain. The heat exchange process between PM material and compressed air increases with upward motion of piston at compression stroke. At the TDC, almost all the air is compressed and closed to PM volume, meanwhile, the fuel is injected into PM chamber to achieve homogenization combustion. - Highlights: •Two-temperature treatment studies the working process of the PM engine. •Self-balancing temperature of the PM determines the continued and stable work. •Stronger heat exchange occurs between gas and PM with smaller porosity. •The PM engine can have lower levels of NO x , unburnt HC and CO emissions

  14. Engineering development studies for molten-salt breeder reactor processing No. 21

    International Nuclear Information System (INIS)

    Hightower, J.R. Jr.

    1976-03-01

    The status of the following programs is reported: (1) continuous fluorinator development: autoresistance heating test AHT-4; (2) development of the metal transfer process; (3) salt-metal contactor development: experiments with a mechanically agitated, nondispersing contactor using water and mercury and in the salt-bismuth flowthrough facility; and (4) fuel reconstitution development: installation of equipment for a fuel reconstitution engineering experiment

  15. Effective Software Engineering Leadership for Development Programs

    Science.gov (United States)

    Cagle West, Marsha

    2010-01-01

    Software is a critical component of systems ranging from simple consumer appliances to complex health, nuclear, and flight control systems. The development of quality, reliable, and effective software solutions requires the incorporation of effective software engineering processes and leadership. Processes, approaches, and methodologies for…

  16. Development status of the Vulcain engine

    Science.gov (United States)

    Gastal, J.; Eury, S.; Borromee, J.; Micewicz, J. B.

    1993-06-01

    The present account of the current status of the Ariane V launch vehicle's Vulcain first-stage cryofueled bipropellant engine gives attention to the Vulcain's overall configuration, as well as to its component designs, operational flowcharts, turbopump and combustion chamber performance verification trials, and program management responsibilities. Prospective development efforts currently envisioned are noted.

  17. Utilization of waste heat from a HCCI (homogeneous charge compression ignition) engine in a tri-generation system

    International Nuclear Information System (INIS)

    Sarabchi, N.; Khoshbakhti Saray, R.; Mahmoudi, S.M.S.

    2013-01-01

    The waste heat from exhaust gases and cooling water of Homogeneous charge compression ignition engines (HCCI) are utilized to drive an ammonia-water cogeneration cycle (AWCC) and some heating processes, respectively. The AWCC is a combination of the Rankine cycle and an absorption refrigeration cycle. Considering the chemical kinetic calculations, a single zone combustion model is developed to simulate the natural gas fueled HCCI engine. Also, the performance of AWCC is simulated using the Engineering Equation Solver software (EES). Through combining these two codes, a detailed thermodynamic analysis is performed for the proposed tri-generation system and the effects of some main parameters on the performances of both the AWCC and the tri-generation system are investigated in detail. The cycle performance is then optimized for the fuel energy saving ratio (FESR). The enhancement in the FESR could be up to 28.56%. Under optimized condition, the second law efficiency of proposed system is 5.19% higher than that of the HCCI engine while the reduction in CO 2 emission is 4.067% as compared with the conventional separate thermodynamic systems. Moreover, the results indicate that the engine, in the tri-generation system and the absorber, in the bottoming cycle has the most contribution in exergy destruction. - Highlights: • A new thermodynamic tri-generation system is proposed for waste heat recovery of HCCI engine. • A single zone combustion model is developed to simulate the natural gas fueled HCCI engine. • The proposed tri-generation cycle is analyzed from the view points of both first and second laws of thermodynamics. • In the considered cycle, enhancements of 28.56% in fuel energy saving ratio and 5.19% in exergy efficiency are achieved

  18. Advanced diesel engine component development program, tasks 4-14

    Science.gov (United States)

    Kaushal, Tony S.; Weber, Karen E.

    1994-01-01

    This report summarizes the Advanced Diesel Engine Component Development (ADECD) Program to develop and demonstrate critical technology needed to advance the heavy-duty low heat rejection engine concept. Major development activities reported are the design, analysis, and fabrication of monolithic ceramic components; vapor phase and solid film lubrication; electrohydraulic valve actuation; and high pressure common rail injection. An advanced single cylinder test bed was fabricated as a laboratory tool in studying these advanced technologies. This test bed simulates the reciprocator for a system having no cooling system, turbo compounding, Rankine bottoming cycle, common rail injection, and variable valve actuation to achieve fuel consumption of 160 g/kW-hr (.26 lb/hp-hr). The advanced concepts were successfully integrated into the test engine. All ceramic components met their functional and reliability requirements. The firedeck, cast-in-place ports, valves, valve guides, piston cap, and piston ring were made from silicon nitride. Breakthroughs required to implement a 'ceramic' engine included the fabrication of air-gap cylinder heads, elimination of compression gaskets, machining of ceramic valve seats within the ceramic firedeck, fabrication of cast-in-place ceramic port liners, implementation of vapor phase lubrication, and elimination of the engine coolant system. Silicon nitride valves were successfully developed to meet several production abuse test requirements and incorporated into the test bed with a ceramic valve guide and solid film lubrication. The ADECD cylinder head features ceramic port shields to increase insulation and exhaust energy recovery. The combustion chamber includes a ceramic firedeck and piston cap. The tribological challenge posed by top ring reversal temperatures of 550 C was met through the development of vapor phase lubrication using tricresyl phosphate at the ring-liner interface. A solenoid-controlled, variable valve actuation system

  19. Advanced diesel engine component development program, tasks 4-14

    Science.gov (United States)

    Kaushal, Tony S.; Weber, Karen E.

    1994-11-01

    This report summarizes the Advanced Diesel Engine Component Development (ADECD) Program to develop and demonstrate critical technology needed to advance the heavy-duty low heat rejection engine concept. Major development activities reported are the design, analysis, and fabrication of monolithic ceramic components; vapor phase and solid film lubrication; electrohydraulic valve actuation; and high pressure common rail injection. An advanced single cylinder test bed was fabricated as a laboratory tool in studying these advanced technologies. This test bed simulates the reciprocator for a system having no cooling system, turbo compounding, Rankine bottoming cycle, common rail injection, and variable valve actuation to achieve fuel consumption of 160 g/kW-hr (.26 lb/hp-hr). The advanced concepts were successfully integrated into the test engine. All ceramic components met their functional and reliability requirements. The firedeck, cast-in-place ports, valves, valve guides, piston cap, and piston ring were made from silicon nitride. Breakthroughs required to implement a 'ceramic' engine included the fabrication of air-gap cylinder heads, elimination of compression gaskets, machining of ceramic valve seats within the ceramic firedeck, fabrication of cast-in-place ceramic port liners, implementation of vapor phase lubrication, and elimination of the engine coolant system. Silicon nitride valves were successfully developed to meet several production abuse test requirements and incorporated into the test bed with a ceramic valve guide and solid film lubrication. The ADECD cylinder head features ceramic port shields to increase insulation and exhaust energy recovery. The combustion chamber includes a ceramic firedeck and piston cap. The tribological challenge posed by top ring reversal temperatures of 550 C was met through the development of vapor phase lubrication using tricresyl phosphate at the ring-liner interface. A solenoid-controlled, variable valve actuation system

  20. Physical principle and engineering features of the deep pool reactor for residential heating

    International Nuclear Information System (INIS)

    Shi Gong; Zhao Zhaoyi; Guo Jingren; Tian Jiafu

    1999-01-01

    The use of nuclear energy for low temperature heating is confronted with challenges of safety and economy. The deep pool reactor, a low temperature heating reactor based on novel design principles, has been studied in detail. Results show that it has excellent safety and economic features, and is very suitable for low temperature heating purposes. The whole heating system including the nuclear reactor will be a simple and easy engineering system with the characteristics of reliability, safety and economy because the system and all its devices are based on low temperature and ordinary pressure

  1. Development of a nonazeotropic heat pump for crew hygiene water heating

    Science.gov (United States)

    Walker, David H.; Deming, Glenn I.

    1991-01-01

    A heat pump system is currently under development to produce hot water for crew hygiene on future manned space missions. The heat pump uses waste heat sources and a nonazeotropic working fluid in a highly efficient cycle. The potential benefits include a reduction in peak power draw from 2 to 5 kW for electric cartridge heaters to just more than 100 W for the heat pump. As part of the heat pump development project, a unique high efficiency compressor was developed to maintain lubrication in a zero-gravity environment.

  2. Developing and modelling of ohmic heating for solid food products

    DEFF Research Database (Denmark)

    Feyissa, Aberham Hailu; Frosch, Stina

    Heating of solid foods using the conventional technologies is time-consuming due to the fact that heat transfer is limited by internal conduction within the product. This is a big challenge to food manufactures who wish to heat the product faster to the desired core temperature and to ensure more...... uniform quality across the product. Ohmic heating is one of the novel technologies potentially solving this problem by allowing volumetric heating of the product and thereby reducing or eliminating temperature gradients within the product. However, the application of ohmic heating for solid food products...... such as meat and seafood is not industrially utilized yet. Therefore, the aim of the current work is to model and develop the ohmic heating technology for heating of solid meat and seafood. A 3D mathematical model of coupled heat transfer and electric field during ohmic heating of meat products has been...

  3. Development of engineering drawing ability for emerging engineering education

    Science.gov (United States)

    Guo, Jian-Wen; Cao, Xiao-Chang; Xie, Li; Jin, Jian-Jun; Wang, Chu-Diao

    2017-09-01

    Students majoring in engineering is required by the emerging engineering education (3E) in the aspect of their ability of engineering drawing. This paper puts forward training mode of engineering drawing ability for 3E. This mode consists of three kinds of training including training in courses, training in competitions and training in actual demand. We also design the feasible implementation plan and supplies viable references to carry out the mode.

  4. Development program on HTTR heat application systems at JAERI

    International Nuclear Information System (INIS)

    Ogawa, M.; Inagaki, Y.; Nishihara, T.; Shimizu, S.; Shiozawa, S.; Miyamoto, Y.

    2000-01-01

    The High Temperature Engineering Test Reactor (HTTR), which is a Japanese High Temperature Gas-cooled Reactor (HTGR) with 30 MW thermal output at 950 deg. C of the coolant outlet temperature, was constructed at Oarai Research Establishment of Japan Atomic Energy Research Institute (JAERI). The HTTR has attained the first criticality on November 1998. In JAERI, a hydrogen production system was selected as a heat utilization system of the HTTR. The development program on the HTTR hydrogen production system consists of two parts: one is to establish technologies connecting the hydrogen production system with the HTTR, the other is to establish technologies producing hydrogen from water by using nuclear heat. Finally, hydrogen can be produced from water by using nuclear heat supplied by the HTTR. In the hydrogen production system connected to the HTTR at first, JAERI selected a steam reforming process because its technology had matured. The HTTR hydrogen production system adopting the steam reforming process is being designed to produce hydrogen of about 3800 Nm 3 /hr by using nuclear heat (10MW, 905 deg. C) supplied from the HTTR. The safety principle and criteria are also being investigated for the HTTR hydrogen production system. A facility for an out-of-pile test prior to the demonstration test with the HTTR hydrogen production system is under manufacturing to carry out tests of safety, controllability and performance. The out-of-pile test facility simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30. The tests will be started in 2001 and continued for 4 years or longer. In parallel to the tests, a hydrogen/tritium permeation test and a corrosion test of a catalyst tube of a steam reformer are being carried out to obtain data necessary for the design of the HTTR hydrogen production system. A kind of thermochemical method called IS process is under studying to produce hydrogen from water by

  5. Wind Energy Workforce Development: Engineering, Science, & Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lesieutre, George A.; Stewart, Susan W.; Bridgen, Marc

    2013-03-29

    Broadly, this project involved the development and delivery of a new curriculum in wind energy engineering at the Pennsylvania State University; this includes enhancement of the Renewable Energy program at the Pennsylvania College of Technology. The new curricula at Penn State includes addition of wind energy-focused material in more than five existing courses in aerospace engineering, mechanical engineering, engineering science and mechanics and energy engineering, as well as three new online graduate courses. The online graduate courses represent a stand-alone Graduate Certificate in Wind Energy, and provide the core of a Wind Energy Option in an online intercollege professional Masters degree in Renewable Energy and Sustainability Systems. The Pennsylvania College of Technology erected a 10 kilowatt Xzeres wind turbine that is dedicated to educating the renewable energy workforce. The entire construction process was incorporated into the Renewable Energy A.A.S. degree program, the Building Science and Sustainable Design B.S. program, and other construction-related coursework throughout the School of Construction and Design Technologies. Follow-on outcomes include additional non-credit opportunities as well as secondary school career readiness events, community outreach activities, and public awareness postings.

  6. Development of Advanced Small Hydrogen Engines

    Energy Technology Data Exchange (ETDEWEB)

    Sapru, Krishna; Tan, Zhaosheng; Chao, Ben

    2010-09-30

    The main objective of the project is to develop advanced, low cost conversions of small (< 25 hp) gasoline internal combustion engines (ICEs) to run on hydrogen fuel while maintaining the same performance and durability. This final technical report summarizes the results of i) the details of the conversion of several small gasoline ICEs to run on hydrogen, ii) the durability test of a converted hydrogen engine and iii) the demonstration of a prototype bundled canister solid hydrogen storage system. Peak power of the hydrogen engine achieves 60% of the power output of the gasoline counterpart. The efforts to boost the engine power with various options including installing the over-sized turbocharger, retrofit of custom-made pistons with high compression ratio, an advanced ignition system, and various types of fuel injection systems are not realized. A converted Honda GC160 engine with ACS system to run with hydrogen fuel is successful. Total accumulative runtime is 785 hours. A prototype bundled canister solid hydrogen storage system having nominal capacity of 1.2 kg is designed, constructed and demonstrated. It is capable of supporting a wide range of output load of a hydrogen generator.

  7. Engineering Education for Sustainable Development. The Contribution of University Curricula to Engineering Education for Sustainable Development.

    NARCIS (Netherlands)

    Kastenhofer, Karen; Lansu, Angelique; Van Dam-Mieras, Rietje; Sotoudeh, Mahshid

    2010-01-01

    Global failures to reach a sustainable development within present-day societies as well as recent breakthroughs within technoscience pose new challenges to engineering education. The list of competencies which engineers should have to rise to these challenges is long and diverse, and often

  8. Research and development of the Chinese nuclear heating reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dazhong, Wang; Wenziang, Zheng; Jiangui, Lin; Changwen, Ma; Duo, Dong [Institute of Nuclear Energy and Technology, Tsinghua Univ., Beijing (China)

    1997-09-01

    The paper presents the significance of nuclear heat application in China as well as the development status, main design features and safety concepts of the nuclear heating reactor exploited by INET. (author). 3 refs, 3 figs, 1 tab.

  9. Develop railway engineering modules in UTK civil engineering undergraduate and graduate courses.

    Science.gov (United States)

    2015-05-31

    The importance of railway transport has long been recognized. However, no railway : engineering courses have been provided in the UTK civil engineering curricula. The : objective of this education project is to develop some railway engineering module...

  10. Computational modelling of an Organic Rankine Cycle (ORC waste heat recovery system for an aircraft engine

    Directory of Open Access Journals (Sweden)

    Saadon S.

    2018-01-01

    Full Text Available Escalating fuel prices and carbon dioxide emission are causing new interest in methods to increase the thrust force of an aircraft engine with limitation of fuel consumption. One viable means is the conversion of exhaust engine waste heat to a more useful form of energy or to be used in the aircraft environmental system. A one-dimensional analysis method has been proposed for the organic Rankine cycle (ORC waste heat recovery system for turbofan engine in this paper. The paper contains two main parts: validation of the numerical model and a performance prediction of turbofan engine integrated to an ORC system. The cycle is compared with industrial waste heat recovery system from Hangzhou Chinen Steam Turbine Power CO., Ltd. The results show that thrust specific fuel consumption (TSFC of the turbofan engine reach lowest value at 0.91 lbm/lbf.h for 7000 lbf of thrust force. When the system installation weight is applied, the system results in a 2.0% reduction in fuel burn. Hence implementation of ORC system for waste heat recovery to an aircraft engine can bring a great potential to the aviation industry.

  11. HEAT ENGINEERING TESTING OF AIR COOLING UNIT OF HORIZONTAL TYPE

    OpenAIRE

    Rohachov, Valerii Andriiovych; Semeniako, Oleksandr Volodymyrovych; Лазоренко, Р. О.; Середа, Р. М.; Parafeinyk, Volodymyr Petrovych

    2018-01-01

    The results of the thermal tests of the section of air cooler, the heat-exchange surface of which is made up of chess package of bimetal finned tubes are presented. The methods of research are presented, the experimental stand is described, the measurement errors are given. The efficiency of the experimental stand and the accuracy of the experimental data on it are confirmed. Proposed to use the stand for researches of air cooling units with other types and sections of finned tubes.

  12. An improved CO_2-based transcritical Rankine cycle (CTRC) used for engine waste heat recovery

    International Nuclear Information System (INIS)

    Shu, Gequn; Shi, Lingfeng; Tian, Hua; Li, Xiaoya; Huang, Guangdai; Chang, Liwen

    2016-01-01

    Highlights: • Propose an improved CTRC system (PR-CTRC) for engine waste heat recovery. • The PR-CTRC achieves a significant increase in thermodynamic performance. • The PR-CTRC possesses a strong coupling capability for high and low grade waste heat. • The PR-CTRC uses smaller turbine design parameters than ORC systems. • Total cooling load analysis of combined engine and recovery system was conducted. - Abstract: CO_2-based transcritical Rankine cycle (CTRC) is a promising technology for the waste heat recovery of an engine considering its safety and environment friendly characteristics, which also matchs the high temperature of the exhaust gas and satisfies the miniaturization demand of recovery systems. But the traditional CTRC system with a basic configuration (B-CTRC) has a poor thermodynamic performance. This paper introduces an improved CTRC system containing both a preheater and regenerator (PR-CTRC), for recovering waste heat in exhaust gas and engine coolant of an engine, and compares its performance with that of the B-CTRC system and also with that of the traditional excellent Organic Rankine Cycle (ORC) systems using R123 as a working fluid. The utilization rate of waste heat, total cooling load, net power output, thermal efficiency, exergy loss, exergy efficiency and component size have been investigated. Results show that, the net power output of the PR-CTRC could reach up to 9.0 kW for a 43.8 kW engine, which increases by 150% compared with that of the B-CTRC (3.6 kW). The PR-CTRC also improves the thermal efficiency and exergy efficiency of the B-CTRC, with increases of 184% and 227%, respectively. Compared with the ORC system, the PR-CTRC shows the significant advantage of highly recycling the exhaust gas and engine coolant simultaneously due to the special property of supercritical CO_2’s specific heat capacity. The supercritical property of CO_2 also generates a better heat transfer and flowing performances. Meanwhile, the PR

  13. A thermoacoustic engine capable of utilizing multi-temperature heat sources

    International Nuclear Information System (INIS)

    Qiu Limin; Wang Bo; Sun Daming; Liu Yu; Steiner, Ted

    2009-01-01

    Low-grade energy is widespread. However, it cannot be utilized with high thermal efficiency directly. Following the principle of thermal energy cascade utilization, a thermoacoustic engine (TE) with a new regenerator that can be driven by multiple heat sources at different temperature levels is proposed. Taking a regenerator that utilizes heat sources at two temperatures as an example, theoretical research has been conducted on a traveling-wave TE with the new regenerator to predict its performance. Experimental verification is also done to demonstrate the benefits of the new regenerator. Results indicate that a TE with the new regenerator utilizing additional heat at a lower temperature experiences an increase in pressure ratio, acoustic power, efficiency, and exergy efficiency with proper heat input at an appropriate temperature at the mid-heater. A regenerator that uses multi-temperature heat sources can provide a means of recovering lower grade heat.

  14. Ecological optimization of quantum spin-1/2 heat engine at the classical limit

    International Nuclear Information System (INIS)

    Chen, T-H

    2006-01-01

    The purpose of this paper is to present a study of finite-time thermodynamics applied to evaluate the ecological performance of a quantum heat engine which operates between two thermal reservoirs using the working substance of spin-1/2 systems. The quantum heat engine cycle is composed of two isothermal processes, an adiabatic process and an isomagnetic field process. A sequence of time evolution was determined from the quantum angular momentum rate based on the semigroup approach and the quantum master equation. The individual time duration is added to account for the total cycle time. The objective ecological function representing a compromise between power output and irreversibility is maximized with respect to cycle temperature ratio. Effects of thermal reservoir temperature ratio and magnetic field ratio on the ecological function have been discussed. A comparison of quantum heat engine performance under maximum ecological function and maximum power conditions is also presented

  15. The Second Law of Thermodynamics in a Quantum Heat Engine Model

    International Nuclear Information System (INIS)

    Zhang Ting; Cai Lifeng; Chen Pingxing; Li Chengzu

    2006-01-01

    The second law of thermodynamics has been proven by many facts in classical world. Is there any new property of it in quantum world? In this paper, we calculate the change of entropy in T.D. Kieu's model for quantum heat engine (QHE) and prove the broad validity of the second law of thermodynamics. It is shown that the entropy of the quantum heat engine neither decreases in a whole cycle, nor decreases in either stage of the cycle. The second law of thermodynamics still holds in this QHE model. Moreover, although the modified quantum heat engine is capable of extracting more work, its efficiency does not improve at all. It is neither beyond the efficiency of T.D. Kieu's initial model, nor greater than the reversible Carnot efficiency.

  16. Development of stress correction formulae for heat formed steel plates

    Directory of Open Access Journals (Sweden)

    Hyung Kyun Lim

    2018-03-01

    Full Text Available The heating process such as line heating, triangular heating and so on is widely used in plate forming of shell plates found in bow and stern area of outer shell in a ship. Local shrinkage during heating process is main physical phenomenon used in plate forming process. As it is well appreciated, the heated plate undergoes the change in material and mechanical properties around heated area due to the harsh thermal process. It is, therefore, important to investigate the changes of physical and mechanical properties due to heating process in order to use them plate the design stage of shell plates. This study is concerned with the development of formula of plastic hardening constitutive equation for steel plate on which line heating is applied. In this study the stress correction formula for the heated plate has been developed based on the numerical simulation of tension test with varying plate thickness and heating speed through the regression analysis of multiple variable case. It has been seen the developed formula shows very good agreement with results of numerical simulation. This paper ends with usefulness of the present formula in examining the structural characteristic of ship's hull. Keywords: Heat input, Heat transfer analysis, Line heating, Shell plate, Stress correction, Thermo-elasto-plastic analysis

  17. Development and application of soil coupled heat pump

    Science.gov (United States)

    Liu, Lu

    2017-05-01

    Soil coupled heat pump technology is a new clean heating mode, is the world's most energy efficient heating one of the ways. And because of the use of renewable geothermal resources with high heating performance so more and more people's attention. Although the use of soil-coupled heat pumps has been in use for more than 50 years (the first application in the United States), the market penetration of this technology is still in its infancy. This paper will focus on the development, characteristics and application of the coupled heat pump.

  18. Modeling and dynamic control simulation of unitary gas engine heat pump

    International Nuclear Information System (INIS)

    Zhao Yang; Haibo Zhao; Zheng Fang

    2007-01-01

    Based on the dynamic model of the gas engine heat pump (GEHP) system, an intelligent control simulation is presented to research the dynamic characteristics of the system in the heating operation. The GEHP system simulation model consists of eight models for its components including a natural gas engine, a compressor, a condenser, an expansion valve, an evaporator, a cylinder jacket heat exchanger, an exhaust gas heat exchanger and an auxiliary heater. The intelligent control model is composed of the prediction controller model and the combined controller model. The Runge-Kutta Fehlberg fourth-fifth order algorithms are used to solve the differential equations. The results show that the model is very effective in analyzing the effects of the control system, and the steady state accuracy of the intelligent control scheme is higher than that of the fuzzy controller

  19. The thermodynamics of heat- and mass exchange in chemical engineering. Vol. 1. 2. rev. ed.

    International Nuclear Information System (INIS)

    Matz, G.

    1979-01-01

    The second and completely revised edition of the approved textbook 'The thermodynamics of heat- and mass exchange in chemical engineering' is devoted to students of technical and natural science disciplines as well as to practicians and scientists, which are confronted with thermodynamical problems of chemical engineering. Starting from the different phases and properties of matter, the first and the second law of thermodynamics are discussed together with many applications. After an introduction of the equilibrium state, the general principle of similarity for heat- and mass exchange is discussed, considering in particular the heat- and mass exchange in the counter flow between two phases. In a final chapter, the heat- and mass exchange between the vapor- and liquid phase is discussed, with special emphasis on problems as evaporation and drying. (orig./HK) [de

  20. Parametric analysis of a dual loop Organic Rankine Cycle (ORC) system for engine waste heat recovery

    International Nuclear Information System (INIS)

    Song, Jian; Gu, Chun-wei

    2015-01-01

    Highlights: • A dual loop ORC system is designed for engine waste heat recovery. • The two loops are coupled via a shared heat exchanger. • The influence of the HT loop condensation parameters on the LT loop is evaluated. • Pinch point locations determine the thermal parameters of the LT loop. - Abstract: This paper presents a dual loop Organic Rankine Cycle (ORC) system consisting of a high temperature (HT) loop and a low temperature (LT) loop for engine waste heat recovery. The HT loop recovers the waste heat of the engine exhaust gas, and the LT loop recovers that of the jacket cooling water in addition to the residual heat of the HT loop. The two loops are coupled via a shared heat exchanger, which means that the condenser of the HT loop is the evaporator of the LT loop as well. Cyclohexane, benzene and toluene are selected as the working fluids of the HT loop. Different condensation temperatures of the HT loop are set to maintain the condensation pressure slightly higher than the atmosphere pressure. R123, R236fa and R245fa are chosen for the LT loop. Parametric analysis is conducted to evaluate the influence of the HT loop condensation temperature and the residual heat load on the LT loop. The simulation results reveal that under different condensation conditions of the HT loop, the pinch point of the LT loop appears at different locations, resulting in different evaporation temperatures and other thermal parameters. With cyclohexane for the HT loop and R245fa for the LT loop, the maximum net power output of the dual loop ORC system reaches 111.2 kW. Since the original power output of the engine is 996 kW, the additional power generated by the dual loop ORC system can increase the engine power by 11.2%.

  1. A combined thermodynamic cycle used for waste heat recovery of internal combustion engine

    International Nuclear Information System (INIS)

    He, Maogang; Zhang, Xinxin; Zeng, Ke; Gao, Ke

    2011-01-01

    In this paper, we present a steady-state experiment, energy balance and exergy analysis of exhaust gas in order to improve the recovery of the waste heat of an internal combustion engine (ICE). Considering the different characteristics of the waste heat of exhaust gas, cooling water, and lubricant, a combined thermodynamic cycle for waste heat recovery of ICE is proposed. This combined thermodynamic cycle consists of two cycles: the organic Rankine cycle (ORC), for recovering the waste heat of lubricant and high-temperature exhaust gas, and the Kalina cycle, for recovering the waste heat of low-temperature cooling water. Based on Peng–Robinson (PR) equation of state (EOS), the thermodynamic parameters in the high-temperature ORC were calculated and determined via an in-house computer program. Suitable working fluids used in high-temperature ORC are proposed and the performance of this combined thermodynamic cycle is analyzed. Compared with the traditional cycle configuration, more waste heat can be recovered by the combined cycle introduced in this paper. -- Highlights: ► We study the energy balance of fuel in internal combustion engine. ► Heat recovery effect of exhaust gas is good when ICE is at a high-load condition. ► We propose a new combined thermodynamic cycle for waste heat of ICE. ► The combined cycle has a higher recovery efficiency than previous configurations.

  2. Metal hydride heat pump engineering demonstration and evaluation model

    Science.gov (United States)

    Lynch, Franklin E.

    1993-01-01

    Future generations of portable life support systems (PLSS's) for space suites (extravehicular mobility units or EMU's) may require regenerable nonventing thermal sinks (RNTS's). For purposes of mobility, a PLSS must be as light and compact as possible. Previous venting PLSS's have employed water sublimators to reject metabolic and equipment heat from EMU's. It is desirable for long-duration future space missions to minimize the use of water and other consumables that need to be periodically resupplied. The emission of water vapor also interferes with some types of instrumentation that might be used in future space exploration. The test article is a type of RNTS based on a metal hydride heat pump (MHHP). The task of reservicing EMU's after use must be made less demanding in terms of time, procedures, and equipment. The capability for quick turnaround post-EVA servicing (30 minutes) is a challenging requirement for many of the RNTS options. The MHHP is a very simple option that can be regenerated in the airlock within the 30 minute limit by the application of a heating source and a cooling sink. In addition, advanced PLSS's must provide a greater degree of automatic control, relieving astronauts of the need to manually adjust temperatures in their liquid cooled ventilation garments (LCVG's). The MHHP includes automatic coolant controls with the ability to follow thermal load swings from minimum to maximum in seconds. The MHHP includes a coolant loop subsystem with pump and controls, regeneration equipment for post-EVA servicing, and a PC-based data acquisition and control system (DACS).

  3. Engineering development in nuclear power plant construction

    International Nuclear Information System (INIS)

    Guenther, P.

    1979-01-01

    Proceeding from the up-to-now experience in the erection of nuclear power stations, especially of the first and second unit of the Greifswald nuclear power plant, the following essential aspects of the development of constructional engineering are discussed: (1) constructional features and criteria, (2) organizational management, (3) current status and problems in prelimary operations, and (4) possibilities of further expenditure reductions in constructing nuclear power stations

  4. Measurement of Heat Flow Transmitted through a Stacked-Screen Regenerator of Thermoacoustic Engine

    Directory of Open Access Journals (Sweden)

    Shu Han Hsu

    2017-03-01

    Full Text Available A stacked-screen regenerator is a key component in a thermoacoustic Stirling engine. Therefore, the choice of suitable mesh screens is important in the engine design. To verify the applicability of four empirical equations used in the field of thermoacoustic engines and Stirling engines, this report describes the measurements of heat flow rates transmitted through the stacked screen regenerator inserted in an experimental setup filled with pressurized Argon gas having mean pressure of 0.45 MPa. Results show that the empirical equations reproduce the measured heat flow rates to a mutually similar degree, although their derivation processes differ. Additionally, results suggest that two effective pore radii would be necessary to account for the viscous and thermal behaviors of the gas oscillating in the stacked-screen regenerators.

  5. Adaptive individual-cylinder thermal state control using intake air heating for a GDCI engine

    Science.gov (United States)

    Roth, Gregory T.; Sellnau, Mark C.

    2016-08-09

    A system for a multi-cylinder compression ignition engine includes a plurality of heaters, at least one heater per cylinder, with each heater configured to heat air introduced into a cylinder. Independent control of the heaters is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the heater for that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder compression ignition engine, including determining a combustion parameter for combustion taking place in a cylinder of the engine and controlling a heater configured to heat air introduced into that cylinder, is also provided.

  6. Challenges in Smart Low-Temperature District Heating Development

    DEFF Research Database (Denmark)

    Li, Hongwei; Wang, Stephen Jia

    2014-01-01

    Previous research and development shows that low temperature district heating (LTDH) system is economic feasible for low energy buildings and buildings at sparse areas. Coupling with reduced network temperature and well-designed district heating (DH) networks, LTDH can reduce network heat loss by...

  7. Development of an electro-osmotic heat pump

    NARCIS (Netherlands)

    Stoel, J.P. van der; Oostendorp, P.A.

    1999-01-01

    The majority of heat pumps and refrigerators is driven by a mechanical compressor. Although they usually function very well, the search for new and in some cases better heat pumping concepts continues. One of the topics in this field is the development of an electro-osmotic heat pump. As each

  8. Diesel Engine Waste Heat Recovery Utilizing Electric Turbocompound Technology

    International Nuclear Information System (INIS)

    Gerke, Frank G.

    2001-01-01

    This cooperative program between the DOE Office of Heavy Vehicle Technology and Caterpillar, Inc. is aimed at demonstrating electric turbocompound technology on a Class 8 truck engine. This is a lab demonstration program, with no provision for on-truck testing of the system. The goal is to demonstrate the level of fuel efficiency improvement attainable with the electric turbocompound system. Also, electric turbocompounding adds an additional level of control to the air supply which could be a component in an emissions control strategy

  9. Quantum thermodynamic cycles and quantum heat engines. II.

    Science.gov (United States)

    Quan, H T

    2009-04-01

    We study the quantum-mechanical generalization of force or pressure, and then we extend the classical thermodynamic isobaric process to quantum-mechanical systems. Based on these efforts, we are able to study the quantum version of thermodynamic cycles that consist of quantum isobaric processes, such as the quantum Brayton cycle and quantum Diesel cycle. We also consider the implementation of the quantum Brayton cycle and quantum Diesel cycle with some model systems, such as single particle in a one-dimensional box and single-mode radiation field in a cavity. These studies lay the microscopic (quantum-mechanical) foundation for Szilard-Zurek single-molecule engine.

  10. Development of a gas fired Vuilleumier heat pump for residential heating

    DEFF Research Database (Denmark)

    Carlsen, Henrik

    1989-01-01

    A natural gas-driven heat pump based on the Vuilleumier principle has been developed for use in single-family houses. The pump has a heat output of 7.5 kW at a coefficient of performance of 1.62 based on the lower heat content of the gas fuel. The heat pump uses helium as working fluid at 20 MPa...... mean pressure, and it is designed as a semihermetic unit. A crank mechanism distinguished by very small loads on the piston rings was developed. The advantages and disadvantages of the Vuilleumier principle for heat-driven heat pumps are discussed. Results of the extensive experimental work...... are presented. A new 20 kW Vuilleumier heat pump is briefly described...

  11. Performance characteristics of a glowplug assisted low heat rejection diesel engine using ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Karthikeyan, B.; Srithar, K. [Department of Mechanical Engineering, Thiagarajar College of Engineering, Madurai, Tamilnadu 625 015 (India)

    2011-01-15

    Conventional diesel engines with ethanol as fuel are associated with problems due to high self-ignition temperature of the fuel. The hot surface ignition method, wherein a part of the injected fuel is made to touch an electrically heated hot surface (glowplug) for ignition, is an effective way of utilizing ethanol in conventional diesel engines. The purpose of the present study is to investigate the effect of thermal insulation on ethanol fueled compression ignition engine. One of the important ethanol properties to be considered in the high compression ratio engine is the long ignition delay of the fuel, normally characterized by lower cetane number. In the present study, the ignition delay was controlled by partial insulation of the combustion chamber (low heat rejection engine) by plasma spray coating of yttria stabilized zirconia for a thickness of 300 {mu}m. Experiments were carried out on the glowplug assisted engine with and without insulation in order to find out the possible benefits of combustion chamber insulation in ethanol and diesel operation. Highest brake thermal efficiency of 32% was obtained with ethanol fuel by insulating the combustion chamber. Emissions of the unburnt hydrocarbons, oxides of nitrogen and carbon monoxides were higher than that of diesel. But the smoke intensity and was less than that of diesel engine. Volumetric efficiency of the engine was reduced by a maximum of 9% in LHR mode of operation. (author)

  12. Performance of a multilevel quantum heat engine of an ideal N-particle Fermi system.

    Science.gov (United States)

    Wang, Rui; Wang, Jianhui; He, Jizhou; Ma, Yongli

    2012-08-01

    We generalize the quantum heat engine (QHE) model which was first proposed by Bender et al. [J. Phys. A 33, 4427 (2000)] to the case in which an ideal Fermi gas with an arbitrary number N of particles in a box trap is used as the working substance. Besides two quantum adiabatic processes, the engine model contains two isoenergetic processes, during which the particles are coupled to energy baths at a high constant energy E(h) and a low constant energy E(c), respectively. Directly employing the finite-time thermodynamics, we find that the power output is enhanced by increasing particle number N (or decreasing minimum trap size L(A)) for given L(A) (or N), without reduction in the efficiency. By use of global optimization, the efficiency at possible maximum power output (EPMP) is found to be universal and independent of any parameter contained in the engine model. For an engine model with any particle-number N, the efficiency at maximum power output (EMP) can be determined under the condition that it should be closest to the EPMP. Moreover, we extend the heat engine to a more general multilevel engine model with an arbitrary 1D power-law potential. Comparison between our engine model and the Carnot cycle shows that, under the same conditions, the efficiency η = 1 - E(c)/E(h) of the engine cycle is bounded from above the Carnot value η(c) =1 - T(c)/T(h).

  13. Electrical and engine driven heat pumps for effective utilisation of renewable energy resources

    Energy Technology Data Exchange (ETDEWEB)

    Aye, Lu; Charters, W.W.S

    2003-07-01

    Much of the energy used for domestic, commercial and industrial purposes is to provide efficient and effective heating of conditioned spaces and for specialist niche applications in process heat systems. Vapour compression heat pumps driven by electric motors or engines provide the real capability of upgrading low temperature sources of ambient and waste heat to match the desired load temperatures in such heating applications. Major source of ambient heat stem from the storage of solar energy in the ground, in lakes and rivers, and in atmospheric air. Heat pumps can therefore be used to effectively harness indirectly the daily solar radiation input. In addition many industries have major sources of waste low grade heat in the form of air or water discharged from the industrial process heat stream. Heat pumps are generally formally classified therefore as air source, ground source or water source units although there has also been considerable interest recently in hybrid units combining the attributes of two or more of these specific types mentioned above.

  14. Electrical and engine driven heat pumps for effective utilisation of renewable energy resources

    Energy Technology Data Exchange (ETDEWEB)

    Lu Aye [Melbourne Univ., Dept. of Civil and Environmental Engineering, Parkville, VIC (Australia); Charters, W.W.S. [Melbourne Univ., Dept. of Mechanical and Manufacturing Engineering, Parkville, VIC (Australia)

    2003-07-01

    Much of the energy used for domestic, commercial and industrial purposes is to provide efficient and effective heating of conditioned spaces and for specialist niche applications in process heat systems. Vapour compression heat pumps driven by electric motors or engines provide the real capability of upgrading low temperature sources of ambient and waste heat to match the desired load temperatures in such heating applications. Major source of ambient heat stem from the storage of solar energy in the ground, in lakes and rivers, and in atmospheric air. Heat pumps can therefore be used to effectively harness indirectly the daily solar radiation input. In addition many industries have major sources of waste low grade heat in the form of air or water discharged from the industrial process heat stream. Heat pumps are generally formally classified therefore as air source, ground source or water source units although there has also been considerable interest recently in hybrid units combining the attributes of two or more of these specific types mentioned above. (Author)

  15. Waste heat recovery systems for internal combustion engines: classification and benefits

    OpenAIRE

    Marchenko, A.; Samoilenko, D.; Adel Hamzah, Ali; Adel Hamzah, Omar

    2014-01-01

    Recent trend about the best ways of using the deployable sources of energy in to useful work in order to reduce the rate of consumption of fossil fuel as well as pollution. Out of all the available sources, the internal combustion engines are the major consumer of fossil fuel around the globe. The remaining heat is expelled to the environment through exhaust gases and engine cooling systems, resulting in to entropy rise and serious environmental pollution, so it is required to utilized waste ...

  16. A novel split cycle internal combustion engine with integral waste heat recovery

    International Nuclear Information System (INIS)

    Dong, Guangyu; Morgan, Robert; Heikal, Morgan

    2015-01-01

    Highlights: • A novel engine thermodynamic cycle is proposed. • Theoretical analysis is applied to identify the key parameters of the thermodynamic cycle. • The key stages of the split cycle are analysed via one-dimensional modelling work. • The effecting mechanism of the split cycle efficiency is analysed. - Abstract: To achieve a step improvement in engine efficiency, a novel split cycle engine concept is proposed. The engine has separate compression and combustion cylinders and waste heat is recovered between the two. Quasi-isothermal compression of the charge air is realised in the compression cylinder while isobaric combustion of the air/fuel mixture is achieved in the combustion cylinder. Exhaust heat recovery between the compression and combustion chamber enables highly efficient recovery of waste heat within the cycle. Based on cycle analysis and a one-dimensional engine model, the fundamentals and the performance of the split thermodynamic cycle is estimated. Compared to conventional engines, the compression work can be significantly reduced through the injection of a controlled quantity of water in the compression cylinder, lowering the gas temperature during compression. Thermal energy can then be effectively recovered from the engine exhaust in a recuperator between the cooled compressor cylinder discharge air and the exhaust gas. The resulting hot high pressure air is then injected into a combustor cylinder and mixed with fuel, where near isobaric combustion leads to a low combustion temperature and reduced heat transferred from the cylinder wall. Detailed cycle simulation indicates a 32% efficiency improvement can be expected compared to the conventional diesel engines.

  17. Conflict between internal combustion engine and thermoelectric generator during waste heat recovery in cars

    Science.gov (United States)

    Korzhuev, M. A.

    2011-02-01

    It is shown that an internal combustion engine and a thermoelectric generator (TEG) arranged on the exhaust pipe of this engine come into the conflict of thermal machines that is related to using the same energy resource. The conflict grows with increasing useful electric power W e of the TEG, which leads to the limitation of both the maximum TEG output power ( W {e/max}) and the possibility of waste heat recovery in cars.

  18. District heating systems for small scale development areas

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, Rory e-mail: rory.mcdougall@online.no; Jensen, Bjoernulf

    2008-09-15

    Building projects are normally developed without considering integrated heating systems, especially where properties are for further sale. Due to focus on energy efficiency and environmental impact it is worth considering district heating systems, which include several energy carriers. The choice of energy carrier is assessed to optimize energy costs, account for environmental impact and obtain reliable heating supply, thus giving an energy flexible system for several buildings as opposed to individual heating systems in each building

  19. Analysis and optimization with ecological objective function of irreversible single resonance energy selective electron heat engines

    International Nuclear Information System (INIS)

    Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui

    2016-01-01

    Ecological performance of a single resonance ESE heat engine with heat leakage is conducted by applying finite time thermodynamics. By introducing Nielsen function and numerical calculations, expressions about power output, efficiency, entropy generation rate and ecological objective function are derived; relationships between ecological objective function and power output, between ecological objective function and efficiency as well as between power output and efficiency are demonstrated; influences of system parameters of heat leakage, boundary energy and resonance width on the optimal performances are investigated in detail; a specific range of boundary energy is given as a compromise to make ESE heat engine system work at optimal operation regions. Comparing performance characteristics with different optimization objective functions, the significance of selecting ecological objective function as the design objective is clarified specifically: when changing the design objective from maximum power output into maximum ecological objective function, the improvement of efficiency is 4.56%, while the power output drop is only 2.68%; when changing the design objective from maximum efficiency to maximum ecological objective function, the improvement of power output is 229.13%, and the efficiency drop is only 13.53%. - Highlights: • An irreversible single resonance energy selective electron heat engine is studied. • Heat leakage between two reservoirs is considered. • Power output, efficiency and ecological objective function are derived. • Optimal performance comparison for three objective functions is carried out.

  20. Experimentally aided development of a turbine heat transfer prediction method

    International Nuclear Information System (INIS)

    Forest, A.E.; White, A.J.; Lai, C.C.; Guo, S.M.; Oldfield, M.L.G.; Lock, G.D.

    2004-01-01

    In the design of cooled turbomachinery blading a central role is played by the computer methods used to optimise the aerodynamic and thermal performance of the turbine aerofoils. Estimates of the heat load on the turbine blading should be as accurate as possible, in order that adequate life may be obtained with the minimum cooling air requirement. Computer methods are required which are able to model transonic flows, which are a mixture of high temperature combustion gases and relatively cool air injected through holes in the aerofoil surface. These holes may be of complex geometry, devised after empirical studies of the optimum shape and the most cost effective manufacturing technology. The method used here is a further development of the heat transfer design code (HTDC), originally written by Rolls-Royce plc under subcontract to Rolls-Royce Inc for the United States Air Force. The physical principles of the modelling employed in the code are explained without extensive mathematical details. The paper describes the calibration of the code in conjunction with a series of experimental measurements on a scale model of a high-pressure nozzle guide vane at non-dimensionally correct engine conditions. The results are encouraging, although indicating that some further work is required in modelling highly accelerated pressure surface flow

  1. Study of SI engine fueled with methanol vapor and dissociation gas based on exhaust heat dissociating methanol

    International Nuclear Information System (INIS)

    Fu, Jianqin; Deng, Banglin; Liu, Jingping; Wang, Linjun; Xu, Zhengxin; Yang, Jing; Shu, Gequn

    2014-01-01

    Highlights: • The full load power decreases successively from gasoline engine, methanol vapor engine to dissociated methanol engine. • Both power and thermal efficiency of dissociated methanol engine can be improved by boosting pressure. • The conversion efficiency of recovered exhaust gas energy is largely influenced by the BMEP. • At the same BMEP, dissociated methanol engine has higher thermal efficiency than methanol vapor engine and gasoline engine. - Abstract: To improve the fuel efficiency of internal combustion (IC) engine and also achieve the goal of direct usage of methanol fuel on IC engine, an approach of exhaust heat dissociating methanol was investigated, which is a kind of method for IC engine exhaust heat recovery (EHR). A bottom cycle system is coupled with the IC engine exhaust system, which uses the exhaust heat to evaporate and dissociate methanol in its catalytic cracker. The methanol dissociation gas (including methanol vapor) is used as the fuel for IC engine. This approach was applied to both naturally aspirated (NA) engine and turbocharged engine, and the engine performance parameters were predicted by the software GT-power under various kinds of operating conditions. The improvement to IC engine performance and the conversion efficiency of recovered exhaust gas energy can be evaluated by comparing the performances of IC engine fueled with various kinds of fuels (or their compositions). Results show that, from gasoline engine, methanol vapor engine to dissociated methanol engine, the full load power decreases successively in the entire speed area due to the declining of volumetric efficiency, while it is contrary in the thermal efficiency at the same brake mean effective pressure (BMEP) level because of the improving of fuel heating value. With the increase of BMEP, the conversion efficiency of recovered exhaust gas energy is promoted. All those results indicate that the approach of exhaust heat dissociating methanol has large

  2. Protein engineering for biofuel production: Recent development

    Directory of Open Access Journals (Sweden)

    Nisha Singh

    2016-09-01

    Full Text Available The unstable and unsure handiness of crude oil sources moreover the rising price of fuels have shifted international efforts to utilize renewable resources for the assembly of greener energy and a replacement which might additionally meet the high energy demand of the globe. Biofuels represent a sustainable, renewable, and also the solely predictable energy supply to fossil fuels. During the green production of Biofuels, several in vivo processes place confidence in the conversion of biomass to sugars by engineered enzymes, and the subsequent conversion of sugars to chemicals via designed proteins in microbial production hosts. Enzymes are indispensable within the effort to provide fuels in an ecologically friendly manner. They have the potential to catalyze reactions with high specificity and potency while not using dangerous chemicals. Nature provides an in depth assortment of enzymes, however usually these should be altered to perform desired functions in needed conditions. Presently available enzymes like cellulose are subject to tight induction and regulation systems and additionally suffer inhibition from numerous end products. Therefore, more impregnable and economical catalyst preparations ought to be developed for the enzymatic method to be more economical. Approaches like protein engineering, reconstitution of protein mixtures and bio prospecting for superior enzymes are gaining importance. Advances in enzyme engineering allow the planning and/or directed evolution of enzymes specifically tailored for such industrial applications. Recent years have seen the production of improved enzymes to help with the conversion of biomass into fuels. The assembly of the many of those fuels is feasible due to advances in protein engineering. This review discusses the distinctive challenges that protein engineering faces in the method of changing lignocellulose to biofuels and the way they're addressed by recent advances in this field.

  3. Efficiency versus speed in quantum heat engines: Rigorous constraint from Lieb-Robinson bound

    Science.gov (United States)

    Shiraishi, Naoto; Tajima, Hiroyasu

    2017-08-01

    A long-standing open problem whether a heat engine with finite power achieves the Carnot efficiency is investgated. We rigorously prove a general trade-off inequality on thermodynamic efficiency and time interval of a cyclic process with quantum heat engines. In a first step, employing the Lieb-Robinson bound we establish an inequality on the change in a local observable caused by an operation far from support of the local observable. This inequality provides a rigorous characterization of the following intuitive picture that most of the energy emitted from the engine to the cold bath remains near the engine when the cyclic process is finished. Using this description, we prove an upper bound on efficiency with the aid of quantum information geometry. Our result generally excludes the possibility of a process with finite speed at the Carnot efficiency in quantum heat engines. In particular, the obtained constraint covers engines evolving with non-Markovian dynamics, which almost all previous studies on this topic fail to address.

  4. Modeling and optimization of integrated exhaust gas recirculation and multi-stage waste heat recovery in marine engines

    DEFF Research Database (Denmark)

    Kyriakidis, Fotis; Sørensen, Kim; Singh, Shobhana

    2017-01-01

    Waste heat recovery combined with exhaust gas recirculation is a promising technology that can address both the issue of NOx (nitrogen oxides) reduction and fuel savings by including a pressurized boiler. In the present study, a theoretical optimization of the performance of two different...... configurations of steam Rankine cycles, with integrated exhaust gas recirculation for a marine diesel engine, is presented. The first configuration employs two pressure levels and the second is configured with three-pressure levels. The models are developed in MATLAB based on the typical data of a large two......-stroke marine diesel engine. A turbocharger model together with a blower, a pre-scrubber and a cooler for the exhaust gas recirculation line, are included. The steam turbine, depending on the configuration, is modeled as either a dual or triple pressure level turbine. The condensation and pre-heating process...

  5. A computer simulation of the turbocharged turbo compounded diesel engine system: A description of the thermodynamic and heat transfer models

    Science.gov (United States)

    Assanis, D. N.; Ekchian, J. E.; Frank, R. M.; Heywood, J. B.

    1985-01-01

    A computer simulation of the turbocharged turbocompounded direct-injection diesel engine system was developed in order to study the performance characteristics of the total system as major design parameters and materials are varied. Quasi-steady flow models of the compressor, turbines, manifolds, intercooler, and ducting are coupled with a multicylinder reciprocator diesel model, where each cylinder undergoes the same thermodynamic cycle. The master cylinder model describes the reciprocator intake, compression, combustion and exhaust processes in sufficient detail to define the mass and energy transfers in each subsystem of the total engine system. Appropriate thermal loading models relate the heat flow through critical system components to material properties and design details. From this information, the simulation predicts the performance gains, and assesses the system design trade-offs which would result from the introduction of selected heat transfer reduction materials in key system components, over a range of operating conditions.

  6. Phase Change Material (PCM) Heat Exchanger Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary focus of the project is to provide future space vehicles a reliable form of long duration supplemental heat rejection (SHREDs). SHREDs allow a vehicle to...

  7. Fuel Composition and Performance Analysis of Endothermically Heated Fuels for Pulse Detonation Engines

    Science.gov (United States)

    2009-03-01

    exchanger was constructed on an inner 2 in Inconel 625 schedule 10 pipe and an outer 2 ½ in Inconel 600 schedule 40 pipe 0.91 m (36 in) in length. The...switched to positions two and three for the remainder of the experiments. 46 The detonation tubes are fabricated from inconel and include heat...and four. Fuel Heating System 47 The fuel heating system centers around two pairs of inconel heat exchangers. The first pair was developed in

  8. Exact analytical thermodynamic expressions for a Brownian heat engine

    Science.gov (United States)

    Taye, Mesfin Asfaw

    2015-09-01

    The nonequilibrium thermodynamics feature of a Brownian motor operating between two different heat baths is explored as a function of time t . Using the Gibbs entropy and Schnakenberg microscopic stochastic approach, we find exact closed form expressions for the free energy, the rate of entropy production, and the rate of entropy flow from the system to the outside. We show that when the system is out of equilibrium, it constantly produces entropy and at the same time extracts entropy out of the system. Its entropy production and extraction rates decrease in time and saturate to a constant value. In the long time limit, the rate of entropy production balances the rate of entropy extraction, and at equilibrium both entropy production and extraction rates become zero. Furthermore, via the present model, many thermodynamic theories can be checked.

  9. Idaho National Engineering Laboratory site development plan

    International Nuclear Information System (INIS)

    1994-09-01

    This plan briefly describes the 20-year outlook for the Idaho National Engineering Laboratory (INEL). Missions, workloads, worker populations, facilities, land, and other resources necessary to fulfill the 20-year site development vision for the INEL are addressed. In addition, the plan examines factors that could enhance or deter new or expanded missions at the INEL. And finally, the plan discusses specific site development issues facing the INEL, possible solutions, resources required to resolve these issues, and the anticipated impacts if these issues remain unresolved

  10. Technology developments for a compound cycle engine

    Science.gov (United States)

    Bobula, George A.; Wintucky, William T.; Castor, J. G.

    1988-01-01

    The Compound Cycle Engine (CCE) is a highly turbocharged, power compounded power plant which combines the light weight pressure rise capability of a gas turbine with the high efficiency of a diesel. When optimized for a rotorcraft, the CCE will reduce fuel burned for a typical 2 hour (plus 30 min reserve) mission by 30 to 40 percent when compared to a conventional advanced technology gas turbine. The CCE can provide a 50 percent increase in range-payload product on this mission. Results of recent activities in a program to establish the technology base for a CCE are presented. The objective of this program is to research and develop those critical technologies which are necessary for the demonstration of a multicylinder diesel core in the early 1990s. A major accomplishment was the initial screening and identification of a lubricant which has potential for meeting the material wear rate limits of the application. An in-situ wear measurement system also was developed to provide accurate, readily obtainable, real time measurements of ring and liner wear. Wear data, from early single cylinder engine tests, are presented to show correlation of the in-situ measurements and the system's utility in determining parametric wear trends. A plan to demonstrate a compound cycle engine by the mid 1990s is included.

  11. Safe corrosion inhibitor for treating cooling water on heat power engineering plants

    Science.gov (United States)

    Nikolaeva, L. A.; Khasanova, D. I.; Mukhutdinova, E. R.; Safin, D. Kh.; Sharifullin, I. G.

    2017-08-01

    Heat power engineering (HPE) consumes significant volumes of water. There are, therefore, problems associated with corrosion, biological fouling, salt deposits, and sludge formation on functional surfaces of heat power equipment. One of the effective ways to solve these problems is the use of inhibitory protection. The development of new Russian import-substituting environmentally friendly inhibitors is very relevant. This work describes experimental results on the OPC-800 inhibitor (TU 2415-092-00206 457-2013), which was produced at Karpov Chemical Plant and designed to remove mineral deposits, scale, and biological fouling from the surfaces of water-rotation node systems on HPE objects. This reagent is successfully used as an effective corrosion inhibitor in the water recycling systems of Tatarstan petrochemical enterprises. To save fresh make-up water, the circulating system is operated in a no-blow mode, which is characterized by high evaporation and salt content coefficients. It was experimentally found that corrosion rate upon treatment of recycled water with the OPC-800 inhibitor is 0.08-0.10 mm/year. HPE mainly uses inhibitors based on oxyethylidene diphosphonic (OEDPA) and nitrilotrimethylphosphonic (NTMPA) acids. The comparative characteristic of inhibition efficiency for OPC-800 and OEDF-Zn-U2 is given. The results obtained indicate that OPC-800 can be used as an inhibitor for treatment of cooling water in HPE plants. In this case, it is necessary to take into account the features of water rotation of a thermal power plant.

  12. Development of limiting decay heat values

    International Nuclear Information System (INIS)

    Khotylev, V.A.; Thompson, J.W.; Gibb, R.A.

    1999-01-01

    A number of tools are used in the assessment of decay heat during an outage of the CANDU-6. Currently, the technical basis for all of these tools is 'CANDU Channel Decay Power', Reference 1. The methods used in that document were limited to channel decay powers. However, for most outage support analysis, decay heat limits are based on bundle heats. Since the production of that document in 1977, new versions of codes, and updates of general-purpose and CANDU-specific libraries have become available. These tools and libraries have both a more formal technical basis than Reference 1, and also a more formal validation base. Using these tools it is now possible to derive decay heat with more specific input parameters, such as fuel composition, heat per unit of fuel, and irradiation history, and to assign systematically derived uncertainty allowances to such decay heat values. In particular, we sought to examine a broad range of likely bundle histories, and thus establish a set of limiting bundle decay beat values, that could serve as a bounding envelope for use in Nuclear Safety Analysis. (author)

  13. Sublimator Driven Coldplate Engineering Development Unit Test Results

    Science.gov (United States)

    Sheth, Rubik B.; Stephan, Ryan A.; Leimkuehler, Thomas O.

    2010-01-01

    The Sublimator Driven Coldplate (SDC) is a unique piece of thermal control hardware that has several advantages over a traditional thermal control scheme. The principal advantage is the possible elimination of a pumped fluid loop, potentially increasing reliability and reducing complexity while saving both mass and power. Because the SDC requires a consumable feedwater, it can only be used for short mission durations. Additionally, the SDC is ideal for a vehicle with small transport distances and low heat rejection requirements. An SDC Engineering Development Unit was designed and fabricated. Performance tests were performed in a vacuum chamber to quantify and assess the performance of the SDC. The test data was then used to develop correlated thermal math models. Nonetheless, an Integrated Sublimator Driven Coldplate (ISDC) concept is being developed. The ISDC couples a coolant loop with the previously described SDC hardware. This combination allows the SDC to be used as a traditional coldplate during long mission phases and provides for dissimilar system redundancy

  14. Research and development in power plant engineering

    International Nuclear Information System (INIS)

    Riedle, K.; Taud, R.

    2001-01-01

    Research and development are a bridge for visions that are escorted to a successful market introduction. Also in power plant engineering, research and development are a lever with which the product power plant, its technology and processes can be adapted to the quickly changing future market. In the overview given by this paper, therefore at first the development boosters and targets are outlined from the viewpoint of the market; then the available technology portfolio is addressed in a concise way. Targets for the development can be seen from the support programmes of the governments. Before a preview is given, some development topics from the point of view of the manufacturer are introduced. (orig.) [de

  15. Performance and heat release analysis of a pilot-ignited natural gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, S.R.; Biruduganti, M.; Mo, Y.; Bell, S.R.; Midkiff, K.C. [Alabama Univ., Dept. of Mechanical Engineering, Tuscaloosa, AL (United States)

    2002-09-01

    The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)

  16. Energy efficiency of gas engine driven heat pumps for heating and cooling applications; Energieeffizienter Einsatz von Gasmotorwaermepumpen fuer Heiz- und Kuehlanwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Juergen [Magdeburg Univ. (Germany). Inst. fuer Stroemungstechnik und Thermodynamik

    2012-11-15

    Heat pumps are gaining in importance for a sustainable and ecological heat supply. Gas engine driven systems can contribute to a decentralized energy supply by power heat cogeneration. In the paper, a pilot plant, which offers high energy efficiency by simultaneous use of the heat of evaporation and condensation, is presented. The plant permits the testing of different operating modes and obtains high values above three for the primary energy ratio. (orig.)

  17. Second law analysis of a diesel engine waste heat recovery with a combined sensible and latent heat storage system

    International Nuclear Information System (INIS)

    Pandiyarajan, V.; Chinnappandian, M.; Raghavan, V.; Velraj, R.

    2011-01-01

    The exhaust gas from an internal combustion engine carries away about 30% of the heat of combustion. The energy available in the exit stream of many energy conversion devices goes as waste. The major technical constraint that prevents successful implementation of waste heat recovery is due to intermittent and time mismatched demand for and availability of energy. The present work deals with the use of exergy as an efficient tool to measure the quantity and quality of energy extracted from a diesel engine and stored in a combined sensible and latent heat storage system. This analysis is utilized to identify the sources of losses in useful energy within the components of the system considered, and provides a more realistic and meaningful assessment than the conventional energy analysis. The energy and exergy balance for the overall system is quantified and illustrated using energy and exergy flow diagrams. In order to study the discharge process in a thermal storage system, an illustrative example with two different cases is considered and analyzed, to quantify the destruction of exergy associated with the discharging process. The need for promoting exergy analysis through policy decision in the context of energy and environment crisis is also emphasized. - Highlights: → WHR with TES system eliminates the mismatch between the supply of energy and demand. → A saving of 15.2% of energy and 1.6% of exergy is achieved with PCM storage. → Use of multiple PCMs with cascaded system increases energy and exergy efficiency.

  18. The Little Heat Engine: Heat Transfer in Solids, Liquids and Gases

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2007-10-01

    Full Text Available In this work, an introductory exposition of the laws of thermodynamics and radiative heat transfer is presented while exploring the concepts of the ideal solid, the lattice, and the vibrational, translational, and rotational degrees of freedom. Analysis of heat transfer in this manner helps scientists to recognize that the laws of thermal radiation are strictly applicable only to the ideal solid. On the Earth, such a solid is best represented by either graphite or soot. Indeed, certain forms of graphite can approach perfect absorption over a relatively large frequency range. Nonetheless, in dealing with heat, solids will eventually sublime or melt. Similarly, liquids will give way to the gas phase. That thermal conductivity eventually decreases in the solid signals an inability to further dissipate heat and the coming breakdown of Planck’s law. Ultimately, this breakdown is reflected in the thermal emission of gases. Interestingly, total gaseous emissivity can de- crease with increasing temperature. Consequently, neither solids, liquids, or gases can maintain the behavior predicted by the laws of thermal emission. Since the laws of thermal emission are, in fact, not universal, the extension of these principles to non-solids constitutes a serious overextension of the work of Kirchhoff, Wien, Stefan and Planck.

  19. The influence of engine speed and load on the heat transfer between gases and in-cylinder walls at fired and motored conditions of an IDI diesel engine

    International Nuclear Information System (INIS)

    Sanli, Ali; Ozsezen, Ahmet N.; Kilicaslan, Ibrahim; Canakci, Mustafa

    2008-01-01

    In this study, the heat transfer characteristics between gases and in-cylinder walls at fired and motored conditions in a diesel engine were investigated by using engine data obtained experimentally. For this investigation, a four-cylinder, indirect injection (IDI) diesel engine was tested under different engine speeds and loads. The heat transfer coefficient was calculated by using Woschni expression correlated for the IDI diesel engines, and also using Annand and Hohenberg expressions. The temperature of in-cylinder gases were determined from a basic model based on the first law of thermodynamics after measuring in-cylinder pressure experimentally. The results show that the heat transfer characteristics of the IDI diesel engine strongly depend on the engine speed and load as a function of crank angle at fired and motored conditions

  20. The influence of engine speed and load on the heat transfer between gases and in-cylinder walls at fired and motored conditions of an IDI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Sanli, Ali; Kilicaslan, Ibrahim [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Ozsezen, Ahmet N.; Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

    2008-08-15

    In this study, the heat transfer characteristics between gases and in-cylinder walls at fired and motored conditions in a diesel engine were investigated by using engine data obtained experimentally. For this investigation, a four-cylinder, indirect injection (IDI) diesel engine was tested under different engine speeds and loads. The heat transfer coefficient was calculated by using Woschni expression correlated for the IDI diesel engines, and also using Annand and Hohenberg expressions. The temperature of in-cylinder gases were determined from a basic model based on the first law of thermodynamics after measuring in-cylinder pressure experimentally. The results show that the heat transfer characteristics of the IDI diesel engine strongly depend on the engine speed and load as a function of crank angle at fired and motored conditions. (author)

  1. Brayton cycle for internal combustion engine exhaust gas waste heat recovery

    Directory of Open Access Journals (Sweden)

    J Galindo

    2015-06-01

    Full Text Available An average passenger car engine effectively uses about one-third of the fuel combustion energy, while the two-thirds are wasted through exhaust gases and engine cooling. It is of great interest to automotive industry to recover some of this wasted energy, thus increasing the engine efficiency and lowering fuel consumption and contamination. Waste heat recovery for internal combustion engine exhaust gases using Brayton cycle machine was investigated. The principle problems of application of such a system in a passenger car were considered: compressor and expander machine selection, machine size for packaging under the hood, efficiency of the cycle, and improvement of engine efficiency. Important parameters of machines design have been determined and analyzed. An average 2-L turbocharged gasoline engine’s New European Driving Cycle points were taken as inlet points for waste heat recovery system. It is theoretically estimated that the recuperated power of 1515 W can be achieved along with 5.7% improvement in engine efficiency, at the point where engine power is 26550 W.

  2. Demonstration of high temperature thermoelectric waste heat recovery from exhaust gases of a combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Trottmann, Matthias; Weidenkaff, Anke; Populoh, Sascha; Brunko, Oliver; Veziridis, Angelika; Bach, Christian; Cabalzar, Urs [Empa, Duebendorf (Switzerland)

    2011-07-01

    The energy efficiency of passenger cars becomes increasingly important due to a growing awareness in terms of climate change and shortages of resources associated with rising fuel prices. In addition to the efforts towards the optimization of the engine's internal efficiency, waste heat recovery is the main objective. In this respect, thermoelectric (TE) devices seem to be suited as heat recuperation systems. Thermoelectric generators allow for direct transformation of thermal into electrical energy. In order to thoroughly investigate this type of recovery system a TE demonstrator was mounted on the muffler of a VW Touran and tested. The waste heat of the exhaust gas was converted into electricity with a conversion rate of {proportional_to}. 3.5%. The limiting factor was the low thermal stability of the commercial modules used in this pre-study to elaborate reference values. Thermoelectric modules based on sustainable and temperature-stable materials are being developed to improve the measured values. A thermoelectric test generator with perovskite-type oxide modules was constructed confirm the function and stability at elevated temperatures. Despite all the advantages of this material class, the TE performance is still to be improved. A quantitative measure of a material's TE performance is the temperature-independent Figure of Merit ZT. ZT increases with decreasing thermal and increasing electrical conductivity. An approach to thermal conductivity reduction is nanostructuring of the material. The Ultrasonic Spray Combustion (USC) technique allows to produce powders with a grain size on the nanoscale and was tested in this study. (orig.)

  3. Experimental characterization of mass, work and heat flows in an air cooled, single cylinder engine

    International Nuclear Information System (INIS)

    Perez-Blanco, H.

    2004-01-01

    Small air cooled engines, although large in numbers, receive scant attention in the literature. Experimental data for a four stroke, air cooled, single cylinder engine are presented in this report. Air to fuel ratios, indicated and output power, exhaust composition and heat loss are determined to result in suitable thermal and mechanical efficiencies. The data obtained are discussed with the perspective obtained from other literature references. Exhaust composition figures appear reasonable, but the measurement of the transient exhaust flows is still a concern. Based on the measurements, a graph illustrating the different energy transformations in the engine is produced. Undergraduate students in the curriculum routinely use the engine and the present work allows one to conclude that the measurement approach produces reasonable results. These results could be used by engine modelers and others interested in this wide field of technology

  4. Testing of a Stirling engine for heat + power cogeneration; Test eines Stirlingmotors zur Kraft-Waerme-Kopplung

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, M.; Heinen, J. [RWE Energy AG, Essen (Germany)

    2007-01-15

    As part of a technology evaluation of distributed energy generators, RWE Energy AG extensively tested a micro combined heat and power appliance, powered by a Stirling engine developed by the British firm Microgen Energy Limited. Microgen Energy Limited is a specialist in micro combined heat and power (microCHP) based on unique Free-Piston Stirling generator technology Microgen is working with leading appliance manufacturers to integrate its core technology into a range of innovative microCHP products. The investigations concentrated on the determination of capacity, efficiency and emissions, the grid connection and behaviour at start-up and under varying loads. This article summarises the results of the tests and gives an overview of micro-CHP technologies (CHP=combined heat and power) and their possible significance to the market in the future. (orig.)

  5. Strategic alliances in engineering, technology and development

    International Nuclear Information System (INIS)

    Jazrawi, W.

    1991-01-01

    The role of strategic alliances in the development of heavy oil resources, both mineable and in-situ, is discussed. A strategic alliance is defined as a custom designed, long term collaborative working arrangement between two parties to pool, exchange, and integrate their resources to maximize mutual gain. A combination of one or more of the following success factors is seen as contributing to the unlocking of static heavy oil resources: sufficiently high and sustained crude oil prices; strategic intent to pursue heavy oil development regardless of short-term setbacks or economic downturns; technology breakthroughs that can reduce bitumen supply and upgrading costs; and strategic alliances. An idealized model for strategic alliances designed to help develop heavy oil resources is illustrated. The advantages and pitfalls involved in strategic alliances are listed along with the characteristics of viable contract agreements for such alliances. Some examples of strategic alliances in engineering and technology development are presented from Alberta experience. 2 figs., 1 tab

  6. Identifying Student Difficulties with Entropy, Heat Engines, and the Carnot Cycle

    Science.gov (United States)

    Smith, Trevor I.; Christensen, Warren M.; Mountcastle, Donald B.; Thompson, John R.

    2015-01-01

    We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students…

  7. Integrated energy and emission management for heavy-duty diesel engines with waste heat recovery system

    NARCIS (Netherlands)

    Willems, F.P.T.; Kupper, F.; Rascanu, G.; Feru, E.

    2015-01-01

    Rankine-cycleWasteHeatRecovery (WHR)systems are promising solutions to reduce fuel consumption for trucks. Due to coupling between engine andWHR system, control of these complex systems is challenging. This study presents an integrated energy and emission management strategy for an Euro-VI Diesel

  8. Integrated energy and emission management for diesel engines with waste heat recovery using dynamic models

    NARCIS (Netherlands)

    Willems, F.P.T.; Kupper, F.; Rascanu, G.C.; Feru, E.

    2015-01-01

    Rankine-cycle Waste Heat Recovery (WHR) systems are promising solutions to reduce fuel consumption for trucks. Due to coupling between engine and WHR system, control of these complex systems is challenging. This study presents an integrated energy and emission management strategy for an Euro-VI

  9. Integrated Energy & Emission Management for Heavy-Duty Diesel Engines with Waste Heat Recovery System

    NARCIS (Netherlands)

    Willems, F.P.T.; Kupper, F.; Cloudt, R.P.M.

    2012-01-01

    This study presents an integrated energy and emission management strategy for an Euro-VI diesel engine with Waste Heat Recovery (WHR) system. This Integrated Powertrain Control (IPC) strategy optimizes the CO2-NOx trade-off by minimizing the operational costs associated with fuel and AdBlue

  10. Control of a waste heat recovery system with decoupled expander for improved diesel engine efficiency

    NARCIS (Netherlands)

    Feru, E.; Willems, F.P.T.; Jager, de A.G.; Steinbuch, M.

    2015-01-01

    In this paper, a switching Model Predictive Control strategy is proposed for a Waste Heat Recovery system in heavy-duty automotive application. The objective is to maximize the WHR system output power while satisfying the output constraints under highly dynamic engine variations. For control design,

  11. Surface engineering glass-metal coatings designed for induction heating of ceramic components

    International Nuclear Information System (INIS)

    Khan, Amir Azam; Labbe, Jean Claude

    2014-01-01

    The term Surface Engineering is of relatively recent origin and use, however, the use of coatings and treatments to render surfaces of materials more suitable for certain application or environment is not new. With the advent of Vacuum Technology, Surface Engineering has gained a whole new impetus, whereby expensive materials with adequate mechanical, chemical and thermal properties are being coated or treated on their surfaces in order to achieve what is called as Surface Engineered materials. The present paper presents an overview of recent achievements in Surface Engineering and gives a detailed view of a specific application where glass-metal composite coatings were deposited on ceramic components in order to render them sensitive to induction heating. Sintered glaze coatings containing silver particles in appropriate concentration can be used for the induction heating of porcelain. Mixtures of glass ceramic powders with silver are used to prepare self-transfer patterns, which are deposited over porcelain. Several configurations of these coatings, which are aesthetic to start with, are employed and heating patterns are recorded. The microstructure of these coatings is discussed in relation to the heating ability by a classical household induction system. The results show that this technique is practical and commercially viable

  12. Phase-space interference in extensive and nonextensive quantum heat engines

    DEFF Research Database (Denmark)

    Hardal, Ali Ümit Cemal; Paternostro, Mauro; Mustecaplioglu, Ozgur E.

    2018-01-01

    Quantum interference is at the heart of what sets the quantum and classical worlds apart. We demonstrate that quantum interference effects involving a many-body working medium is responsible for genuinely nonclassical features in the performance of a quantum heat engine. The features with which...

  13. Supervisory control of a heavy-duty diesel engine with an electrified waste heat recovery system

    NARCIS (Netherlands)

    Feru, E.; Murgovski, N.; de Jager, A.G.; Willems, F.P.T.

    This paper presents an integrated energy and emission management strategy, called Integrated Powertrain Control (IPC), for an Euro-VI diesel engine with an electrified waste heat recovery system. This strategy optimizes the CO2–NOxCO2–NOx trade-off by minimizing the operational costs associated with

  14. Integrated energy and emission management for heavy-duty diesel engines with waste heat recovery system

    NARCIS (Netherlands)

    Willems, F.P.T.; Kupper, F.; Cloudt, R.P.M.

    2012-01-01

    This study presents an integrated energy and emission management strategy for an Euro-VI diesel engine with Waste Heat Recovery (WHR) system. This Integrated Powertrain Control (IPC) strategy optimizes the CO2-NOx trade-off by minimizing the operational costs associated with fuel and AdBlue

  15. Biodiesel From waste cooking oil for heating, lighting, or running diesel engines

    Science.gov (United States)

    Rico O. Cruz

    2009-01-01

    Biodiesel and its byproducts and blends can be used as alternative fuel in diesel engines and for heating, cooking, and lighting. A simple process of biodiesel production can utilize waste cooking oil as the main feedstock to the transesterification and cruzesterification processes. I currently make my own biodiesel for applications related to my nursery and greenhouse...

  16. Review of organic Rankine cycles for internal combustion engine exhaust waste heat recovery

    International Nuclear Information System (INIS)

    Sprouse, Charles; Depcik, Christopher

    2013-01-01

    Escalating fuel prices and future carbon dioxide emission limits are creating a renewed interest in methods to increase the thermal efficiency of engines beyond the limit of in-cylinder techniques. One promising mechanism that accomplishes both objectives is the conversion of engine waste heat to a more useful form of energy, either mechanical or electrical. This paper reviews the history of internal combustion engine exhaust waste heat recovery focusing on Organic Rankine Cycles since this thermodynamic cycle works well with the medium-grade energy of the exhaust. Selection of the cycle expander and working fluid are the primary focus of the review, since they are regarded as having the largest impact on system performance. Results demonstrate a potential fuel economy improvement around 10% with modern refrigerants and advancements in expander technology. -- Highlights: ► This review article focuses on engine exhaust waste heat recovery works. ► The organic Rankine cycle is superior for low to medium exergy heat sources. ► Working fluid and expander selection strongly influence efficiency. ► Several authors demonstrate viable systems for vehicle installation

  17. Sustainable Development in Engineering Education: A Pedagogical Approach

    Science.gov (United States)

    Ahrens, A.; Zascerinska, J.

    2012-01-01

    Engineering education is facing a challenge of the development of student engineers' social responsibility in the context of sustainable development. The aim of the research is to analyze efficiency of engineering curriculum in the context of sustainable development underpinning elaboration of pedagogical guidelines on the development of students'…

  18. Gas engine driven reversible heat pumps: Innovative design. Realizzazione di una pompa di calore reversibile azionata da motore a gas

    Energy Technology Data Exchange (ETDEWEB)

    Canci, F.; Zecchin, M.

    1992-01-01

    This paper describes the development of a series of gas engine driven air-water compression heat pumps designed for reversible summer-winter operation. The development work was carried out within the framework of a joint venture combing the efforts of the Italian Gas Society, Natural Gas of Barcellona and Climaveneta of Vicenza (Italy), who acted as the heat pump constructor. The main objective of this venture was to develop a series of machines that would be suitable for the contemporaneous summer air conditioning and winter space heating of medium-sized buildings. The designs were optimized to allow cost and energy savings with respect to conventional equipment. The useful cooling power range of the innovative heat pump systems goes from 100 to 250 kW thus giving them the flexibility not yet afforded by conventional equipment currently sold on international markets. In addition to pointing out the new heat pumps' main design and performance features, this paper suggests some feasible applications.

  19. Effects of heating energy and heating position on the conversion characteristics of the catalyst of a four-stroke motorcycle engine in cold start conditions

    International Nuclear Information System (INIS)

    Horng, R.-F.; Chou, H.-M.; Hsu, T.-C.

    2004-01-01

    The effects of heating energy and heating position on the conversion efficiency of an electrically heated catalyst of a four stroke motorcycle engine under cold start conditions were investigated in this study. In general, during cold start, the operating temperatures of a four stroke motorcycle engine and its catalyst would not be optimized. It was found in this paper that by applying heat to the catalyst however, the reaction of the catalyst could be promoted, which, consequently, improved the conversion efficiency. The experimented parameters were heating energy, heating position, heating temperature and the carbon monoxide (CO) setting level. The heating temperatures included 100, 140 and 180 deg. C, while three different heating powers and six different heating positions were used. The CO levels were set as 1.0%, 1.8% and 2.3%. The best CO conversion efficiency was obtained by applying heating at the inlet of the catalyst. It was revealed that a high heating power induced a high temperature rising rate and, consequently, a high CO conversion efficiency. In terms of energy economy efficiency, however, heating at the mid-section of the catalyst gave the best results and through a relatively low heating power

  20. Microstructural engineering applied to the controlled cooling of steel wire rod: Part I. Experimental design and heat transfer

    Science.gov (United States)

    Campbell, P. C.; Hawbolt, E. B.; Brimacombe, J. K.

    1991-11-01

    The goal of this study was to develop a mathematical model which incorporates heat flow, phase transformation kinetics, and property-structure-composition relationships to predict the mechanical properties of steel rod being control cooled under industrial conditions. Thus, the principles of microstructural engineering have been brought to bear on this interdisciplinary problem by combining computer modeling with laboratory measurements of heat flow, austenite decomposition kinetics, microstructure and mechanical properties, and industrial trials to determine heat transfer and obtain rod samples under known conditions. Owing to the length and diversity of the study, it is reported in three parts,[8191]the first of which is concerned with the heat flow measurements. A relatively simple and reliable technique, involving a preheated steel rod instrumented with a thermocouple secured at its centerline, has been devised to determine the cooling rate in different regions of the moving bed of rod loops on an operating Stelmor line. The measured thermal response of the rod has been analyzed by two transient conduction models (lumped and distributed parameter, respectively) to yield overall heat-transfer coefficients for radiation and convection. The adequacy of the technique has been checked by cooling instrumented rods under well-defined, air crossflow conditions in the laboratory and comparing measured heat-transfer coefficients to values predicted from well-established equations. The industrial thermal measurements have permitted the characterization of a coefficient to account for radiative interaction among adjacent rod loops near the edge and at the center of the bed.

  1. Stack Parameters Effect on the Performance of Anharmonic Resonator Thermoacoustic Heat Engine

    KAUST Repository

    Nouh, Mostafa A.

    2014-01-01

    A thermoacoustic heat engine (TAHE) converts heat into acoustic power with no moving parts. It exhibits several advantages over traditional engines, such as simple design, stable functionality, and environment-friendly working gas. In order to further improve the performance of TAHE, stack parameters need to be optimized. Stack\\'s position, length and plate spacing are the three main parameters that have been investigated in this study. Stack\\'s position dictates both the efficiency and the maximum produced acoustic power of the heat engine. Positioning the stack closer to the pressure anti-node might ensure high efficiency on the expense of the maximum produced acoustic power. It is noticed that the TAHE efficiency can further be improved by spacing the plates of the stack at a value of 2.4 of the thermal penetration depth, δk . Changes in the stack length will not affect the efficiency much as long as the temperature gradient across the stack, as a ratio of the critical temperature gradient ψ is more than 1. Upon interpreting the effect of these variations, attempts are made towards reaching the engine\\'s most powerful operating point.

  2. Membrane-based osmotic heat engine with organic solvent for enhanced power generation from low-grade heat.

    Science.gov (United States)

    Shaulsky, Evyatar; Boo, Chanhee; Lin, Shihong; Elimelech, Menachem

    2015-05-05

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl-methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl-water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher OHE energy efficiency with the LiCl-methanol draw solution compared to that with the LiCl-water draw solution under practical operating conditions (i.e., heat recovery<90%). We discuss the implications of the results for converting low-grade heat to power.

  3. Membrane-Based Osmotic Heat Engine with Organic Solvent for Enhanced Power Generation from Low-Grade Heat

    Energy Technology Data Exchange (ETDEWEB)

    Shaulsky, E; Boo, C; Lin, SH; Elimelech, M

    2015-05-05

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher ORE energy efficiency with the LiCl methanol draw solution compared to that with the LiCl water draw solution under practical operating conditions (i.e., heat recovery <90%). We discuss the implications of the results for converting low-grade heat to power.

  4. Comparative evaluation of three alternative power cycles for waste heat recovery from the exhaust of adiabatic diesel engines

    Science.gov (United States)

    Bailey, M. M.

    1985-01-01

    Three alternative power cycles were compared in application as an exhaust-gas heat-recovery system for use with advanced adiabatic diesel engines. The power cycle alternatives considered were steam Rankine, organic Rankine with RC-1 as the working fluid, and variations of an air Brayton cycle. The comparison was made in terms of fuel economy and economic payback potential for heavy-duty trucks operating in line-haul service. The results indicate that, in terms of engine rated specific fuel consumption, a diesel/alternative-power-cycle engine offers a significant improvement over the turbocompound diesel used as the baseline for comparison. The maximum imporvement resulted from the use of a Rankine cycle heat-recovery system in series with turbocompounding. The air Brayton cycle alternatives studied, which included both simple-cycle and compression-intercooled configurations, were less effective and provided about half the fuel consumption improvement of the Rankine cycle alternatives under the same conditions. Capital and maintenance cost estimates were also developed for each of the heat-recovery power cycle systems. These costs were integrated with the fuel savings to identify the time required for net annual savings to pay back the initial capital investment. The sensitivity of capital payback time to arbitrary increases in fuel price, not accompanied by corresponding hardware cost inflation, was also examined. The results indicate that a fuel price increase is required for the alternative power cycles to pay back capital within an acceptable time period.

  5. Effects of PM fouling on the heat exchange effectiveness of wave fin type EGR cooler for diesel engine use

    Science.gov (United States)

    Jang, Sang-Hoon; Hwang, Se-Joon; Park, Sang-Ki; Choi, Kap-Seung; Kim, Hyung-Man

    2012-06-01

    Developing an effective method of reducing nitrogen oxide emissions is an important goal in diesel engine research. The use of cooled exhaust gas recirculation has been considered one of the most effective techniques of reducing nitrogen oxide. However, since the combustion characteristics in a diesel engine involves high temperature and load, the amount of particulate matter emission tends to increase, and there is a trade-off between the amount of nitrogen oxide and particulate matter emissions. In the present study, engine dynamometer experiments are performed to investigate the effects of particulate matter fouling on the heat exchange characteristics of wave fin type exhaust gas recirculation coolers that have four cases of two wave pitch and three fin pitch lengths. To optimize the fin and wave pitches of the EGR cooler, the exhaust gas temperature, pressure drop and heat exchange effectiveness are compared. The experimental results show that the exhaust gas recirculation cooler with a fin pitch of 3.6 mm and a wave pitch of 8.8 mm exhibits better heat exchange characteristics and smaller particulate matter fouling effect than the other coolers.

  6. Effects of PM fouling on the heat exchange effectiveness of wave fin type EGR cooler for diesel engine use

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Sang-Hoon; Hwang, Se-Joon; Choi, Kap-Seung; Kim, Hyung-Man [INJE University, Department of Mechanical Engineering, High Safety Vehicle Core Technology Research Center, Gimhae-si, Gyeongnam-do (Korea, Republic of); Park, Sang-Ki [Hanyang University, Graduate School of Mechanical Engineering, Ansan, Gyeonggido (Korea, Republic of)

    2012-06-15

    Developing an effective method of reducing nitrogen oxide emissions is an important goal in diesel engine research. The use of cooled exhaust gas recirculation has been considered one of the most effective techniques of reducing nitrogen oxide. However, since the combustion characteristics in a diesel engine involves high temperature and load, the amount of particulate matter emission tends to increase, and there is a trade-off between the amount of nitrogen oxide and particulate matter emissions. In the present study, engine dynamometer experiments are performed to investigate the effects of particulate matter fouling on the heat exchange characteristics of wave fin type exhaust gas recirculation coolers that have four cases of two wave pitch and three fin pitch lengths. To optimize the fin and wave pitches of the EGR cooler, the exhaust gas temperature, pressure drop and heat exchange effectiveness are compared. The experimental results show that the exhaust gas recirculation cooler with a fin pitch of 3.6 mm and a wave pitch of 8.8 mm exhibits better heat exchange characteristics and smaller particulate matter fouling effect than the other coolers. (orig.)

  7. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI Compendex*plus database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  8. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI Compendex*plus database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  9. Advancing Systems Engineering Excellence: The Marshall Systems Engineering Leadership Development Program

    Science.gov (United States)

    Hall, Philip; Whitfield, Susan

    2011-01-01

    As NASA undertakes increasingly complex projects, the need for expert systems engineers and leaders in systems engineering is becoming more pronounced. As a result of this issue, the Agency has undertaken an initiative to develop more systems engineering leaders through its Systems Engineering Leadership Development Program; however, the NASA Office of the Chief Engineer has also called on the field Centers to develop mechanisms to strengthen their expertise in systems engineering locally. In response to this call, Marshall Space Flight Center (MSFC) has developed a comprehensive development program for aspiring systems engineers and systems engineering leaders. This presentation will summarize the two-level program, which consists of a combination of training courses and on-the-job, developmental training assignments at the Center to help develop stronger expertise in systems engineering and technical leadership. In addition, it will focus on the success the program has had in its pilot year. The program hosted a formal kickoff event for Level I on October 13, 2009. The first class includes 42 participants from across MSFC and Michoud Assembly Facility (MAF). A formal call for Level II is forthcoming. With the new Agency focus on research and development of new technologies, having a strong pool of well-trained systems engineers is becoming increasingly more critical. Programs such as the Marshall Systems Engineering Leadership Development Program, as well as those developed at other Centers, help ensure that there is an upcoming generation of trained systems engineers and systems engineering leaders to meet future design challenges.

  10. Role of quantum correlations in light-matter quantum heat engines

    Science.gov (United States)

    Barrios, G. Alvarado; Albarrán-Arriagada, F.; Cárdenas-López, F. A.; Romero, G.; Retamal, J. C.

    2017-11-01

    We study a quantum Otto engine embedding a working substance composed of a two-level system interacting with a harmonic mode. The physical properties of the substance are described by a generalized quantum Rabi model arising in superconducting circuit realizations. We show that light-matter quantum correlation reduction during the hot bath stage and adiabatic stages act as an indicator for enhanced work extraction and efficiency, respectively. Also, we demonstrate that the anharmonic spectrum of the working substance has a direct impact on the transition from heat engine into refrigerator as the light-matter coupling is increased. These results shed light on the search for optimal conditions in the performance of quantum heat engines.

  11. Modern mechanical engineering research, development and education

    CERN Document Server

    2014-01-01

    This book covers modern subjects of mechanical engineering such as nanomechanics and nanotechnology, mechatronics and robotics, computational mechanics, biomechanics, alternative energies, sustainability as well as all aspects related with mechanical engineering education. The chapters help enhance the understanding of both the fundamentals of mechanical engineering and its application to the solution of problems in modern industry. This book is suitable for students, both in final undergraduate mechanical engineering courses or at the graduate level. It also serves as a useful reference for academics, mechanical engineering researchers, mechanical, materials and manufacturing engineers, professionals in related with mechanical engineering.

  12. Center Planning and Development Student Engineer

    Science.gov (United States)

    Jenkins, Kenneth T.

    2013-01-01

    This fall I was the Student Trainee (Engineering) Pathways Intern (co-op) at the Kennedy Space Center (KSC) in the Center Planning Development (CPD) Directorate. CPD works with commercial companies who are interested using KSCs unique capabilities in spaceflight, spacecraft processing, ground systems and Research Development (RD) projects that fall in line with NASAs mission and goals. CPD is divided into four (4) groups: (1) AD-A, which works on the Master Planning for center, (2) AD-B (where I am), which works on project management and integration, (3) AD-C, which works on partnership development, and (4) AD-T, which works on the RD aspects of partnerships. CPDs main goal is to one day make KSC the worlds largest spaceport and maintain the center as a leader in space exploration. CPD is a very diverse group with employees having a wide knowledge of not only the Space Shuttle, but also that of the Apollo era. Our director of CPD, Scott Colloredo, is on the advisory board for Commercial Space Operations (CSO) and has a degree at ERAU. I worked on a number of different tasks for AD-B, as well as CPD, that includes, but not limited to: reviewing and reissuing engineering drawings from the Apollo and Shuttle eras, to supporting NASA rocket launches (MAVEN), and working on actual agreementsproposals that will be used in the partnership process with multiple partners. Most of the work I have done is sensitive information and cannot be disclosed.

  13. Developing safety culture in nuclear power engineering

    International Nuclear Information System (INIS)

    Tevlin, S.A.

    2000-01-01

    The new issue (no. 11) of the IAEA publications series Safety Reports, devoted to the safety culture in nuclear engineering Safety culture development in the nuclear activities. Practical recommendations to achieve success, is analyzed. A number of recommendations of international experts is presented and basic general indicators of satisfactory and insufficient safety culture in the nuclear engineering are indicated. It is shown that the safety culture has two foundations: human behavior and high quality of the control system. The necessity of creating the confidence by the management at all levels of the enterprise, development of individual initiative and responsibility of the workers, which make it possible to realize the structural hierarchic system, including technical, human and organizational constituents, is noted. Three stages are traced in the process of introducing the safety culture. At the first stage the require,emts of scientific-technical documentation and provisions of the governmental, regional and control organs are fulfilled. At the second stage the management of the organization accepts the safety as an important direction in its activities. At the third stage the organization accomplishes its work, proceeding from the position of constant safety improvement. The general model of the safety culture development is considered [ru

  14. Modeling and Control of a Parallel Waste Heat Recovery System for Euro-VI Heavy-Duty Diesel Engines

    NARCIS (Netherlands)

    Feru, E.; Willems, F.P.T.; Jager, B. de; Steinbuch, M.

    2014-01-01

    This paper presents the modeling and control of a waste heat recovery system for a Euro-VI heavy-duty truck engine. The considered waste heat recovery system consists of two parallel evaporators with expander and pumps mechanically coupled to the engine crankshaft. Compared to previous work, the

  15. Modeling and control of a parallel waste heat recovery system for Euro-VI heavy-duty diesel engines

    NARCIS (Netherlands)

    Feru, E.; Willems, F.P.T.; Jager, de A.G.; Steinbuch, M.

    2014-01-01

    This paper presents the modeling and control of a waste heat recovery systemfor a Euro-VI heavy-duty truck engine. The considered waste heat recovery system consists of two parallel evaporators with expander and pumps mechanically coupled to the engine crankshaft. Compared to previous work, the

  16. Comparative study of different exhaust heat exchangers effect on the performance and exergy analysis of a diesel engine

    NARCIS (Netherlands)

    Hatami, M.; Boot, M.D.; Ganji, D.D.; Gorji-Bandpy, M.

    2015-01-01

    In this research, the effect of three designed heat exchangers on the performance of an OM314 diesel engine and its exergy balance is investigated. Vortex generator heat exchanger (HEX), optimized finned-tube HEX and non-optimized HEX are considered and mounted on the exhaust of diesel engine.

  17. A Systems Engineering Approach to Architecture Development

    Science.gov (United States)

    Di Pietro, David A.

    2015-01-01

    Architecture development is often conducted prior to system concept design when there is a need to determine the best-value mix of systems that works collectively in specific scenarios and time frames to accomplish a set of mission area objectives. While multiple architecture frameworks exist, they often require use of unique taxonomies and data structures. In contrast, this paper characterizes architecture development using terminology widely understood within the systems engineering community. Using a notional civil space architecture example, it employs a multi-tier framework to describe the enterprise level architecture and illustrates how results of lower tier, mission area architectures integrate into the enterprise architecture. It also presents practices for conducting effective mission area architecture studies, including establishing the trade space, developing functions and metrics, evaluating the ability of potential design solutions to meet the required functions, and expediting study execution through the use of iterative design cycles

  18. Development of heat exchangers for nuclear service

    International Nuclear Information System (INIS)

    Hodge, R.I.; Dalrymple, D.G.

    1976-01-01

    Unusual design constraints, due to tube vibration, are called for when tube-in-shell heat exchangers are incorporated into CANDU type reactor power plants. CRNL has programs studying tube excitation and response, flow conditions, and the fretting process in such exchangers, tube plugging techniques, and eddy current scanning systems for inside bores of full-length tubes. (E.C.B.)

  19. Research Proposal for the Design and Engineering Phase of a Solar Heating and Cooling System Experiment at the Warner Robins Public Library, Warner Robins, Georgia. Submitted to the United States Energy Research and Development Administration.

    Science.gov (United States)

    Phillips, Warren H.; And Others

    A number of reasons are advanced to include a solar heating and cooling experiment in a library building. The unique aspects of the experiment are to be a seasonally adjustable collector tilt and testing of a new generation of absorption air conditioners. After a brief description of the proposed experiment, the proposal contains forms filed by…

  20. Waste heat recovery from adiabatic diesel engines by exhaust-driven Brayton cycles

    Science.gov (United States)

    Khalifa, H. E.

    1983-01-01

    An evaluation of Bryton Bottoming Systems (BBS) as waste heat recovery devices for future adiabatic diesel engines in heavy duty trucks is presented. Parametric studies were performed to evaluate the influence of external and internal design parameters on BBS performance. Conceptual design and trade-off studies were undertaken to estimate the optimum configuration, size, and cost of major hardware components. The potential annual fuel savings of long-haul trucks equipped with BBS were estimated. The addition of a BBS to a turbocharged, nonaftercooled adiabatic engine would improve fuel economy by as much as 12%. In comparison with an aftercooled, turbocompound engine, the BBS-equipped turbocharged engine would offer a 4.4% fuel economy advantage. If installed in tandem with an aftercooled turbocompound engine, the BBS could effect a 7.2% fuel economy improvement. The cost of a mass-produced 38 Bhp BBS is estimated at about $6460 or 170/Bhp. Technical and economic barriers that hinder the commercial introduction of bottoming systems were identified. Related studies in the area of waste heat recovery from adiabatic diesel engines and NASA-CR-168255 (Steam Rankine) and CR-168256 (Organic Rankine).

  1. Studies of dynamic contact of ceramics and alloys for advanced heat engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gaydos, P.A.; Dufrane, K.F. [Battelle, Columbus, OH (United States)

    1993-06-01

    Advanced materials and coatings for low heat rejection engines have been investigated for almost a decade. Much of the work has concentrated on the critical wear interface between the piston ring and cylinder liner. Simplified bench tests have identified families of coatings with high temperature wear performance that could meet or exceed that of conventional engine materials at today`s operating temperatures. More recently, engine manufacturers have begun to optimize material combinations and manufacturing processes so that the materials not only have promising friction and wear performance but are practical replacements for current materials from a materials and manufacturing cost standpoint. In this study, the advanced materials supplied by major diesel engine manufacturers were evaluated in an experimental apparatus that simulates many of the in-cylinder conditions of a low heat rejection diesel engine. Results include ring wear factors and average dynamic friction coefficients measured at intervals during the test. These results are compared with other advanced materials tested in the past as well as the baseline wear of current engines. Both fabricated specimens and sections of actual ring and cylinder liners were used in the testing. Observations and relative friction and wear performance of the individual materials are provided.

  2. Systems design and engineering : facilitating multidisciplinary development projects

    NARCIS (Netherlands)

    Bonnema, Gerrit Maarten; Veenvliet, Karel; Broenink, Johannes F.

    2016-01-01

    As its name implies, the aim of Systems Design and Engineering: Facilitating Multidisciplinary Development Projects is to help systems engineers develop the skills and thought processes needed to successfully develop and implement engineered systems. Such expertise typically does not come through

  3. 77 FR 14462 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2012-03-09

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development....S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and Development.... Name: Research, Engineering & Development Advisory Committee. Time and Date: April 18, 2012--9:30 a.m...

  4. 77 FR 54648 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2012-09-05

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development....S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and Development...: Research, Engineering & Development Advisory Committee. TIME AND DATE: September 26, 2012--9 a.m. to 4 p.m...

  5. 76 FR 12404 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2011-03-07

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development....S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and Development...: Research, Engineering & Development Advisory Committee. Time and Date: April 20, 2011--9:30 a.m. to 4 p.m...

  6. 75 FR 14243 - Research, Engineering And Development Advisory Committee

    Science.gov (United States)

    2010-03-24

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering And Development....S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and Development...: Research, Engineering & Development Advisory Committee. Time and Date: April 21, 2010--9 a.m. to 5 p.m...

  7. 76 FR 44648 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2011-07-26

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development....S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and Development.... Name: Research, Engineering & Development Advisory Committee. Time and Date: September 21, 2011--9 a.m...

  8. 78 FR 16357 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2013-03-14

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development... hereby given of a meeting of the FAA Research, Engineering and Development (R,E&D) Advisory Committee. Name: Research, Engineering & Development Advisory Committee. Time and Date: April 24--8:30 a.m. to 4...

  9. An Experimental Investigation on the Combustion and Heat Release Characteristics of an Opposed-Piston Folded-Cranktrain Diesel Engine

    Directory of Open Access Journals (Sweden)

    Fukang Ma

    2015-06-01

    Full Text Available In opposed-piston folded-cranktrain diesel engines, the relative movement rules of opposed-pistons, combustion chamber components and injector position are different from those of conventional diesel engines. The combustion and heat release characteristics of an opposed-piston folded-cranktrain diesel engine under different operating conditions were investigated. Four phases: ignition delay, premixed combustion, diffusion combustion and after combustion are used to describe the heat release process of the engine. Load changing has a small effect on premixed combustion duration while it influences diffusion combustion duration significantly. The heat release process has more significant isochoric and isobaric combustion which differs from the conventional diesel engine situation, except at high exhaust pressure and temperature, due to its two-stroke and uniflow scavenging characteristics. Meanwhile, a relatively high-quality exhaust heat energy is produced in opposed-piston folded-cranktrain diesel engines.

  10. Numerical investigation of two- and three-dimensional heat transfer in expander cycle engines

    Science.gov (United States)

    Burch, Robert L.; Cheung, Fan-Bill

    1993-01-01

    The concept of using tube canting for enhancing the hot-side convective heat transfer in a cross-stream tubular rocket combustion chamber is evaluated using a CFD technique in this study. The heat transfer at the combustor wall is determined from the flow field generated by a modified version of the PARC Navier-Stokes Code, using the actual dimensions, fluid properties, and design parameters of a split-expander demonstrator cycle engine. The effects of artificial dissipation on convergence and solution accuracy are investigated. Heat transfer results predicted by the code are presented. The use of CFD in heat transfer calculations is critically examined to demonstrate the care needed in the use of artificial dissipation for good convergence and accurate solutions.

  11. Superconducting-circuit quantum heat engine with frequency resolved thermal baths

    Science.gov (United States)

    Hofer, Patrick P.; Souquet, Jean-René; Clerk, Aashish A.

    The study of quantum heat engines promises to unravel deep, fundamental concepts in quantum thermodynamics. With this in mind, we propose a novel, realistic device that efficiently converts heat into work while maintaining reasonably large output powers. The key concept in our proposal is a highly peaked spectral density in both the thermal baths as well as the working fluid. This allows for a complete separation of the heat current from the working fluid. In our setup, Cooper pairs tunnelling across a Josephson junction serve as the the working fluid, while two resonant cavities coupled to the junction act as frequency-resolved thermal baths. The device is operated such that a heat flux carried entirely by the photons induces an electrical current against a voltage bias, providing work.

  12. Laser Processed Condensing Heat Exchanger Technology Development

    Science.gov (United States)

    Hansen, Scott; Wright, Sarah; Wallace, Sarah; Hamilton, Tanner; Dennis, Alexander; Zuhlke, Craig; Roth, Nick; Sanders, John

    2017-01-01

    The reliance on non-permanent coatings in Condensing Heat Exchanger (CHX) designs is a significant technical issue to be solved before long-duration spaceflight can occur. Therefore, high reliability CHXs have been identified by the Evolvable Mars Campaign (EMC) as critical technologies needed to move beyond low earth orbit. The Laser Processed Condensing Heat Exchanger project aims to solve these problems through the use of femtosecond laser processed surfaces, which have unique wetting properties and potentially exhibit anti-microbial growth properties. These surfaces were investigated to identify if they would be suitable candidates for a replacement CHX surface. Among the areas researched in this project include microbial growth testing, siloxane flow testing in which laser processed surfaces were exposed to siloxanes in an air stream, and manufacturability.

  13. Measurement improvements of heat flux probes for internal combustion engine; Nainen kikan ni okeru netsuryusokukei no kaihatsu to kento

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, H; Tasaka, H [Miyazaki University, Miyazaki (Japan)

    1997-10-01

    In heat flux measurement in engines, material properties of a heat flux probe and numerical prediction of those influence have been discussed rather than practical measurement accuracy. This study featured the process for the quantitative examination of heat flux probes. Although the process required direct comparison among all the probes and additional measurements in a constant volume bomb, precision of heat flux measurement was greatly improved so that the essential characteristics of heat transfer in engines can be detected. 9 refs., 8 figs., 1 tab.

  14. Roles of plasma neutron source reactor in development of fusion reactor engineering: Comparison with fission reactor engineering

    International Nuclear Information System (INIS)

    Hirayama, Shoichi; Kawabe, Takaya

    1995-01-01

    The history of development of fusion power reactor has come to a turning point, where the main research target is now shifting from the plasma heating and confinement physics toward the burning plasma physics and reactor engineering. Although the development of fusion reactor system is the first time for human beings, engineers have experience of development of fission power reactor. The common feature between them is that both are plants used for the generation of nuclear reactions for the production of energy, nucleon, and radiation on an industrial scale. By studying the history of the development of the fission reactor, one can find the existence of experimental neutron reactors including irradiation facilities for fission reactor materials. These research neutron reactors played very important roles in the development of fission power reactors. When one considers the strategy of development of fusion power reactors from the points of fusion reactor engineering, one finds that the fusion neutron source corresponds to the neutron reactor in fission reactor development. In this paper, the authors discuss the roles of the plasma-based neutron source reactors in the development of fusion reactor engineering, by comparing it with the neutron reactors in the history of fission power development, and make proposals for the strategy of the fusion reactor development. 21 refs., 6 figs

  15. The ion source development for neutral injection heating at JAERI

    International Nuclear Information System (INIS)

    Shirakata, H.; Itoh, T.; Kondoh, U.; Matsuda, S.; Ohara, Y.; Ohga, T.; Shibata, T.; Sugawara, T.; Tanaka, S.

    1976-01-01

    The neutral beam research and development effort at JAERI has been mainly concentrated on design, construction and testing of ion sources needed for present and planned heating experiments. Fundamental characteristics of the ion sources developed are described

  16. Investigation of the effect of heated ethanol fuel on combustion and emissions of an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang

    2016-01-01

    Highlights: • Effect of EDI heating on the EDI + GPI engine performance was investigated. • CO and HC were significantly reduced and NO was slightly increased by EDI heating. • IMEP and combustion speed were slightly reduced by EDI heating. • EDI heating is effective to address the evaporation and over-cooling issues of EDI + GPI engine. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to utilise ethanol fuel more efficiently and flexibly in spark ignition engines. One issue needs to be addressed in the development of EDI + GPI is the ethanol fuel’s low vapour pressure and large latent heat which slow down the ethanol’s evaporation and result in the mixture unready for combustion by the time of spark ignition and the consequent increase of CO and HC emissions. Heating the ethanol fuel to be directly injected (EDI heating) has been proposed to address this issue. This paper reports the investigation of the effect of EDI heating on the combustion and emissions of a research engine equipped with EDI + GPI. The results showed that EDI heating effectively reduced the CO and HC emissions of the engine due to the increase of evaporation rate and reduced fuel impingement and local over-cooling. The reduction of CO and HC became more significant with the increase of ethanol ratio. When the temperature of the ethanol fuel was increased by 40 °C, the CO and HC were reduced by as much as 43% and 51% respectively in EDI only condition at the original spark timing of 15 CAD BTDC, and 15% and 47% respectively at the minimum spark advance for best torque (MBT) timing of 19 CAD BTDC. On the other hand, the NO emission was slightly increased, but still much smaller than that in GPI only condition due to the strong cooling effect and low combustion temperature of EDI. The IMEP and combustion speed were slightly reduced by EDI heating due to the decrease of injector fuel flow rate and spray collapse of flash-boiling. The

  17. Market development directory for solar industrial process heat systems

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-02-01

    The purpose of this directory is to provide a basis for market development activities through a location listing of key trade associations, trade periodicals, and key firms for three target groups. Potential industrial users and potential IPH system designers were identified as the prime targets for market development activities. The bulk of the directory is a listing of these two groups. The third group, solar IPH equipment manufacturers, was included to provide an information source for potential industrial users and potential IPH system designers. Trade associates and their publications are listed for selected four-digit Standard Industrial Code (SIC) industries. Since industries requiring relatively lower temperature process heat probably will comprise most of the near-term market for solar IPH systems, the 80 SIC's included in this chapter have process temperature requirements less than 350/sup 0/F. Some key statistics and a location list of the largest plants (according to number of employees) in each state are included for 15 of the 80 SIC's. Architectural/engineering and consulting firms are listed which are known to have solar experience. Professional associated and periodicals to which information on solar IPH sytstems may be directed also are included. Solar equipment manufacturers and their associations are listed. The listing is based on the SERI Solar Energy Information Data Base (SEIDB).

  18. Design, calibration and error analysis of instrumentation for heat transfer measurements in internal combustion engines

    Science.gov (United States)

    Ferguson, C. R.; Tree, D. R.; Dewitt, D. P.; Wahiduzzaman, S. A. H.

    1987-01-01

    The paper reports the methodology and uncertainty analyses of instrumentation for heat transfer measurements in internal combustion engines. Results are presented for determining the local wall heat flux in an internal combustion engine (using a surface thermocouple-type heat flux gage) and the apparent flame-temperature and soot volume fraction path length product in a diesel engine (using two-color pyrometry). It is shown that a surface thermocouple heat transfer gage suitably constructed and calibrated will have an accuracy of 5 to 10 percent. It is also shown that, when applying two-color pyrometry to measure the apparent flame temperature and soot volume fraction-path length, it is important to choose at least one of the two wavelengths to lie in the range of 1.3 to 2.3 micrometers. Carefully calibrated two-color pyrometer can ensure that random errors in the apparent flame temperature and in the soot volume fraction path length will remain small (within about 1 percent and 10-percent, respectively).

  19. Developing a New Industrial Engineering Curriculum Using a Systems Engineering Approach

    Science.gov (United States)

    Buyurgan, Nebil; Kiassat, Corey

    2017-01-01

    This paper reports on the development of an engineering curriculum for a new industrial engineering programme at a medium-sized private university in the northeast United States. A systems engineering process has been followed to design and develop the new curriculum. Considering the programme curriculum as a system, first the stakeholders have…

  20. Nonlinear dynamics analysis of a low-temperature-differential kinematic Stirling heat engine

    Science.gov (United States)

    Izumida, Yuki

    2018-03-01

    The low-temperature-differential (LTD) Stirling heat engine technology constitutes one of the important sustainable energy technologies. The basic question of how the rotational motion of the LTD Stirling heat engine is maintained or lost based on the temperature difference is thus a practically and physically important problem that needs to be clearly understood. Here, we approach this problem by proposing and investigating a minimal nonlinear dynamic model of an LTD kinematic Stirling heat engine. Our model is described as a driven nonlinear pendulum where the motive force is the temperature difference. The rotational state and the stationary state of the engine are described as a stable limit cycle and a stable fixed point of the dynamical equations, respectively. These two states coexist under a sufficient temperature difference, whereas the stable limit cycle does not exist under a temperature difference that is too small. Using a nonlinear bifurcation analysis, we show that the disappearance of the stable limit cycle occurs via a homoclinic bifurcation, with the temperature difference being the bifurcation parameter.

  1. Stack Parameters Effect on the Performance of Anharmonic Resonator Thermoacoustic Heat Engine

    KAUST Repository

    Nouh, Mostafa A.; Arafa, Nadim M.; Abdel-Rahman, Ehab

    2014-01-01

    A thermoacoustic heat engine (TAHE) converts heat into acoustic power with no moving parts. It exhibits several advantages over traditional engines, such as simple design, stable functionality, and environment-friendly working gas. In order to further improve the performance of TAHE, stack parameters need to be optimized. Stack's position, length and plate spacing are the three main parameters that have been investigated in this study. Stack's position dictates both the efficiency and the maximum produced acoustic power of the heat engine. Positioning the stack closer to the pressure anti-node might ensure high efficiency on the expense of the maximum produced acoustic power. It is noticed that the TAHE efficiency can further be improved by spacing the plates of the stack at a value of 2.4 of the thermal penetration depth, δk . Changes in the stack length will not affect the efficiency much as long as the temperature gradient across the stack, as a ratio of the critical temperature gradient ψ is more than 1. Upon interpreting the effect of these variations, attempts are made towards reaching the engine's most powerful operating point.

  2. Geothermal energy developments in the district heating of Szeged

    OpenAIRE

    Osvald, Máté; Szanyi, János; Medgyes, Tamás; Kóbor, Balázs; Csanádi, Attila

    2017-01-01

    The District Heating Company of Szeged supplies heat and domestic hot water to 27,000 households and 500 public buildings in Szeged. In 2015, the company decided to introduce geothermal sources into 4 of its 23 heating circuits and started the preparation activities of the development. Preliminary investigations revealed that injection into the sandstone reservoir and the hydraulic connection with already existing wells pose the greatest hydrogeological risks, while placement and operation of...

  3. Designing a heat pipe to improve the exhaust emissions from petrol engines

    International Nuclear Information System (INIS)

    Elmabrouk, A.M.

    2010-01-01

    The national engineering Laboratory and the Shell research laboratory have co-operated in applying the heat pipe to the problem of exhaust emission from petrol engine. It is known that the carbon monoxide CO, un-burnt hydrocarbons (H x C y ) and oxides of Nitrogen (NO x ) content of the exhaust will vary with air to fuel ratio as shown in figure (1), in a conventional car engine the maximum efficiency is achieved at 15:1 and maximum power is obtained at 12:1. It's known that as the air fuel ratio increases, the CO content decreases and H x C y , NO x go through a minimum and maximum respectively. A considerable important in both CO and NO x content could be chivied by selecting a very weak mixture, but this not possible in a standard engine carburetor system due to the ignition difficulty, because the fuel is not fully vaporized, and because the fuel is not distributed equally between the cylinders and the vapor content is not as high as it should be due to the pressure of liquid fuel. This problem could be solved by designing a heat pipe that can transferring a certain quantities of heat from the exhaust to the induction manifold at the carburetor outlet as shown in figure (2). Under this condition a mixture as lean as 22:1 will ignite with out difficulty. In this paper, a complete design of heat pipe is carried out, taking into account the necessary criteria to decide various geometrical parameters. The design has been carried out using basic formulas in thermodynamics, heat transfer and physics. The result of this design have been checked for various practical limits. (author)

  4. Study of working fluid selection of organic Rankine cycle (ORC) for engine waste heat recovery

    International Nuclear Information System (INIS)

    Wang, E.H.; Zhang, H.G.; Fan, B.Y.; Ouyang, M.G.; Zhao, Y.; Mu, Q.H.

    2011-01-01

    Organic Rankine Cycle (ORC) could be used to recover low-grade waste heat. When a vehicle is running, the engine exhaust gas states have a wide range of variance. Defining the operational conditions of the ORC that achieve the maximum utilization of waste heat is important. In this paper the performance of different working fluids operating in specific regions was analyzed using a thermodynamic model built in Matlab together with REFPROP. Nine different pure organic working fluids were selected according to their physical and chemical properties. The results were compared in the regions when net power outputs were fixed at 10 kW. Safety levels and environmental impacts were also evaluated. The outcomes indicate that R11, R141b, R113 and R123 manifest slightly higher thermodynamic performances than the others; however, R245fa and R245ca are the most environment-friendly working fluids for engine waste heat-recovery applications. The optimal control principle of ORC under the transient process is discussed based on the analytical results. -- Highlights: → R11, R141b, R113 and R123 manifest the best thermodynamic performances. → R245fa and R245ca are the most environment-friendly working fluids for the engine waste heat-recovery application. → The condensing temperature has more important effect than the evaporating pressure to the performance of ORC. → The optimal control principle of ORC under the transient process was defined according to the calculation results for the vehicle engine waste heat-recovery application. → ORC thermodynamic model was built in Matlab together with REFPROP.

  5. Recent developments of diffusion processes and their applications fluid, heat and mass

    CERN Document Server

    Öchsner, Andreas; Murch, Graeme

    2015-01-01

    This topical volume on ""Recent Developments of Diffusion Processes and their Applications: Fluid, Heat and Mass"" addresses diffusion in a wider sense with a special focus on technical applications. Diffusion phenomena play an important role in the development of modern engineering materials and related fields. Understanding these different transport phenomena at many levels, from atomistic to macro, has therefore long attracted the attention of many researchers in materials science and engineering and related disciplines. The present topical volume captures a representative cross-section of

  6. Development of ergonomic website for engineering education

    Directory of Open Access Journals (Sweden)

    Faradilla Arnes

    2018-01-01

    Full Text Available Engineering education contains two aspects; theory and practice. Practice activity supports the students to implement the theory obtained in the class. Therefore, it will be better if the theory has material visualization in order to support and make easier the student and lecturer in teaching activity. Analisis Perancangan Kerja dan Ergonomi (APK & E is one of the laboratories in Industrial Engineering, Universitas Islam Indonesia. APK & E laboratory which uses website as a tool to communicate to the students. Currently, the existing website still show standard display by conventional way. Based on the questionnaire, the student difficult to understand the material especially for Micromotion Study since this material requires the video to show the student in assembly activity. Augmented Reality (AR combines the real and virtual objects that interactive in the real time and registered in 3D space. AR also combines the real and virtual in displaying information in the real time, in a way that enhances the individual abilities to operate the system in the real world. The system which combines between AR and Micromotion Study was come up. The required software to develop the online AR system is FLARToolKit 2.5.1. In this research, marker detection accuracy measurement of the used toolkit has been conducted and it showed 85% of accuracy level.

  7. Educating the Engineer for Sustainable Community Development

    Science.gov (United States)

    Munoz, D. R.

    2008-12-01

    More than ever before, we are confronting the challenges of limited resources (water, food, energy and mineral), while also facing complex challenges with the environment and related social unrest. Resource access problems are exacerbated by multi-scale geopolitical instability. We seek a balance that will allow profit but also leave a world fit for our children to inherit. Many are working with small groups to make positive change through finding solutions that address these challenges. In fact, some say that in sum, it is the largest human movement that has ever existed. In this talk I will share our experiences to alleviate vulnerabilities for populations of humans in need while working with students, corporate entities and non governmental organizations. Our main focus is to educate a new cadre of engineers that have an enhanced awareness of and better communication skills for a different cultural environment than the one in which they were raised and are hungry to seek new opportunities to serve humanity at a basic level. The results of a few of the more than forty humanitarian engineering projects completed since 2003 will be superimposed on a theoretical framework for sustainable community development. This will be useful information to those seeking a social corporate position of responsibility and a world that more closely approaches a sustainable equilibrium.

  8. Recent Development of the Two-Stroke Engine. II - Design Features. 2; Design Features

    Science.gov (United States)

    Zeman, J.

    1945-01-01

    Completing the first paper dealing with charging methods and arrangements, the present paper discusses the design forms of two-stroke engines. Features which largely influence piston running are: (a) The shape and surface condition of the sliding parts. (b) The cylinder and piston materials. (c) Heat conditions in the piston, and lubrication. There is little essential difference between four-stroke and two-stroke engines with ordinary pistons. In large engines, for example, are always found separately cast or welded frames in which the stresses are taken up by tie rods. Twin piston and timing piston engines often differ from this design. Examples can be found in many engines of German or foreign make. Their methods of operation will be dealt with in the third part of the present paper, which also includes the bibliography. The development of two-stroke engine design is, of course, mainly concerned with such features as are inherently difficult to master; that is, the piston barrel and the design of the gudgeon pin bearing. Designers of four-stroke engines now-a-days experience approximately the same difficulties, since heat stresses have increased to the point of influencing conditions in the piston barrel. Features which notably affect this are: (a) The material. (b) Prevailing heat conditions.

  9. Some developing concepts of engineering education

    Science.gov (United States)

    Perkins, C. D.

    1975-01-01

    An analysis of the circumstances which have created a shortage of aeronautical engineering undergraduate students in the universities is presented. Suggestions for motivating students to enter aeronautical engineering are examined. The support of the aeronautical industry for graduate education funding is recommended. Examples of actions taken by governmental agencies to promote increased interest in aeronautical engineering are included.

  10. Bildung and identity development in engineering education

    DEFF Research Database (Denmark)

    Du, Xiangyun

    2006-01-01

    a social context. The analysis of empirical data shows that studying engineering involves not only the mastery of scientific knowledge and technical skills, but also learning the language, established practices, beliefs, values, and norms in the engineering culture, and learning to become an engineer...

  11. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    International Nuclear Information System (INIS)

    Clark, J.S.; Walton, J.T.; Mcguire, M.L.

    1992-07-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines. 11 refs

  12. A novel cascade organic Rankine cycle (ORC) system for waste heat recovery of truck diesel engines

    International Nuclear Information System (INIS)

    Chen, Tao; Zhuge, Weilin; Zhang, Yangjun; Zhang, Lei

    2017-01-01

    Highlights: • A confluent cascade expansion ORC (CCE-ORC) system is proposed. • Cyclopentane is considered as the most suitable fluid for this system. • The CCE-ORC system performance under full operating conditions is analyzed. • The BSFC of diesel engine can be reduced by 9.2% with the CCE-ORC system. • Performance comparison of CCE-ORC and dual-loop ORC is conducted. - Abstract: Waste heat recovery (WHR) of engines has attracted increasingly more concerns recently, as it can improve engine thermal efficiency and help truck manufacturers meet the restrictions of CO_2 emission. The organic Rankine cycle (ORC) has been considered as the most potential technology of WHR. To take full advantage of waste heat energy, the waste heat in both exhaust gases and the coolant need to be recovered; however, conventional multi-source ORC systems are too complex for vehicle applications. This paper proposed a confluent cascade expansion ORC (CCE-ORC) system for engine waste heat recovery, which has simpler architecture, a smaller volume and higher efficiency compared with conventional dual-loop ORC systems. Cyclopentane is analyzed to be regarded as the most suitable working fluid for this novel system. A thermodynamic simulation method is established for this system, and off-design performance of main components and the working fluid side pressure drop in the condenser have been taken into consideration. System performance simulations under full engine operating conditions are conducted for the application of this system on a heavy-duty truck diesel engine. Results show that the engine peak thermal efficiency can be improved from 45.3% to 49.5% where the brake specific fuel consumption (BSFC) decreases from 185.6 g/(kW h) to 169.9 g/(kW h). The average BSFC in the frequently operating region can decrease by 9.2% from 187.9 g/(kW h) to 172.2 g/(kW h). Compared with the conventional dual-loop ORC system, the CCE-ORC system can generate 8% more net power, while the

  13. Heat pipe heat exchangers in heat recovery systems

    Energy Technology Data Exchange (ETDEWEB)

    Stulc, P; Vasiliev, L L; Kiseljev, V G; Matvejev, Ju N

    1985-01-01

    The results of combined research and development activities of the National Research Institute for Machine Design, Prague, C.S.S.R. and the Institute for Heat and Mass Transfer, Minsk, U.S.S.R. concerning intensification heat pipes used in heat pipe heat exchangers are presented. This sort of research has been occasioned by increased interest in heat power economy trying to utilise waste heat produced by various technological processes. The developed heat pipes are deployed in construction of air-air, gas-air or gas-gas heat recovery exchangers in the field of air-engineering and air-conditioning. (author).

  14. Engineering for high heat loads on ALS [Advanced Light Source] beamlines

    International Nuclear Information System (INIS)

    DiGennaro, R.; Swain, T.

    1989-08-01

    This paper discussed general thermal engineering problems and specific categories of thermal design issues for high photon flux beam lines at the LBL Advanced Light Source: thermal distortion of optical surfaces and elevated temperatures of thermal absorbers receiving synchrotron radiation. A generic design for water-cooled heat absorbers is described for use with ALS photon shutters, beam defining apertures, and heat absorbing masks. Also, results of in- situ measurements of thermal distortion of a water-cooled mirror in a synchrotron radiation beam line are compared with calculated performance estimates. 17 refs., 2 figs

  15. The universal power and efficiency characteristics for irreversible reciprocating heat engine cycles

    CERN Document Server

    Qin Xiao Yong; Sun Feng Rui; Wu Chih

    2003-01-01

    The performance of irreversible reciprocating heat engine cycles with heat transfer loss and friction-like term loss is analysed using finite-time thermodynamics. The universal relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, and the optimal relation between power output and the efficiency of the cycles are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of cycle processes on the performance of the cycle using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson and Brayton cycles.

  16. Numerical model and investigations of the externally heated valve Joule engine

    Energy Technology Data Exchange (ETDEWEB)

    Wojewoda, Jerzy [University of Aberdeen, School of Engineering, Fraser Noble Bldg, Aberdeen AB24 3UE (United Kingdom); Kazimierski, Zbyszko [Technical University of Lodz, Institute of Turbomachinery, 219/223 Wolczanska Str., 93-005 Lodz (Poland)

    2010-05-15

    The mineral fuels used recently, i.e., oil and gas, will be soon exploited out. This paper presents an idea of the engine where any fuel or solar heat can be used as a source of energy. The proposed model is an externally heated, 2-stroke, valve engine (EHVE). This is a piston-type engine, entirely different from the well-known Stirling one, which is the best known example of such a solution. It works in a closed Joule cycle and is designed to produce a moderate amount of energy. The engine is composed of typical parts met in piston designs: an expander, a compressor, a heater, a cooler and, additionally, two recirculation blowers, which consume a small amount of produced power. An additional advantage is its working medium, which may be simply atmospheric air and the engine has a conventional crankshaft and an oil lubrication system. It has already been proven that operation of the EHVE is possible with satisfactory power and efficiency at the output. Comparisons of the EHVE action with and without recirculation blowers are performed. (author)

  17. Rabi model as a quantum coherent heat engine: From quantum biology to superconducting circuits

    Science.gov (United States)

    Altintas, Ferdi; Hardal, Ali Ü. C.; Müstecaplıoǧlu, Özgür E.

    2015-02-01

    We propose a multilevel quantum heat engine with a working medium described by a generalized Rabi model which consists of a two-level system coupled to a single-mode bosonic field. The model is constructed to be a continuum limit of a quantum biological description of light-harvesting complexes so that it can amplify quantum coherence by a mechanism which is a quantum analog of classical Huygens clocks. The engine operates in a quantum Otto cycle where the working medium is coupled to classical heat baths in the isochoric processes of the four-stroke cycle, while either the coupling strength or the resonance frequency is changed in the adiabatic stages. We found that such an engine can produce work with an efficiency close to the Carnot bound when it operates at low temperatures and in the ultrastrong-coupling regime. The interplay of the effects of quantum coherence and quantum correlations on the engine performance is discussed in terms of second-order coherence, quantum mutual information, and the logarithmic negativity of entanglement. We point out that the proposed quantum Otto engine can be implemented experimentally with modern circuit quantum electrodynamic systems where flux qubits can be coupled ultrastrongly to superconducting transmission-line resonators.

  18. Exhaust gas heat recovery through secondary expansion cylinder and water injection in an internal combustion engine

    Directory of Open Access Journals (Sweden)

    Nassiri Toosi Ali

    2017-01-01

    Full Text Available To enhance thermal efficiency and increase performance of an internal combustion engine, a novel concept of coupling a conventional engine with a secondary 4-stroke cylinder and direct water injection process is proposed. The burned gases after working in a traditional 4-stroke combustion cylinder are transferred to a secondary cylinder and expanded even more. After re-compression of the exhaust gases, pre-heated water is injected at top dead center. The evaporation of injected water not only recovers heat from exhaust gases, but also increases the mass of working gas inside the cylinder, therefore improves the overall thermal efficiency. A 0-D/1-D model is used to numerically simulate the idea. The simulations outputs showed that the bottoming cycle will be more efficient at higher engines speeds, specifically in a supercharged/turbocharged engine, which have higher exhaust gas pressure that can reproduce more positive work. In the modeled supercharged engine, results showed that brake thermal efficiency can be improved by about 17%, and brake power by about 17.4%.

  19. 78 FR 47049 - Research, Engineering and Development Advisory Committee

    Science.gov (United States)

    2013-08-02

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Research, Engineering and Development...; 5 U.S.C. App. 2), notice is hereby given of a meeting of the FAA Research, Engineering and.... Name: Research, Engineering & Development Advisory Committee. Time and Date: September 18--8:30 a.m. to...

  20. Advanced tendencies in development of photovoltaic cells for power engineering

    Science.gov (United States)

    Strebkov, D. S.

    2015-01-01

    Development of solar power engineering must be based on original innovative Russian and world technologies. It is necessary to develop promising Russian technologies of manufacturing of photovoltaic cells and semiconductor materials: chlorine-free technology for obtaining solar silicon; matrix solar cell technology with an efficiency of 25-30% upon the conversion of concentrated solar, thermal, and laser radiation; encapsulation technology for high-voltage silicon solar modules with a voltage up to 1000 V and a service life up to 50 years; new methods of concentration of solar radiation with the balancing illumination of photovoltaic cells at 50-100-fold concentration; and solar power systems with round-the-clock production of electrical energy that do not require energy storage devices and reserve sources of energy. The advanced tendency in silicon power engineering is the use of high-temperature reactions in heterogeneous modular silicate solutions for long-term (over one year) production of heat and electricity in the autonomous mode.