WorldWideScience

Sample records for air engine coolant

  1. Air coolant system

    International Nuclear Information System (INIS)

    The main patent relates to a process of cooling the steam from the turbine working with a nuclear power reactor, in said process a two-phase fluid mixture is circulated inside a closed circuit between the turbine condenser and a cooling tower. The present addition to the main patent relates to a cooling system comprising instead of the vertical tower, a nearly horizontal structure open to wind, in which the air is circulated by natural convection. The lower part of said structure, according to the invention, comprises two parallel rows of nearly rectangular cooling fins and the upper part consists of two walls made antiparallel with respect to the longitudinal symmetry plane of said structure and thus forming an upwards widening, the resulting vertical planar section of the long-shaped cooling structure according to the invention assuming a venturi shape. Said type of structure a few hundred meters long but only fifty meters high is less visible in the landscape than the vertical tower, and condensation clouds are formed onside a larger surface, that is another ecological advantage

  2. AUTOMOTIVE AND HEAVY-DUTY ENGINE COOLANT RECYCLING BY FILTRATION

    Science.gov (United States)

    This evaluation addresses the product quality, waste reduction and economic issues involved in recycling automotive and heavy-duty engine coolants. he specific recycling units evaluated are a fleet-size unit and a portable unit, both based on the technology of chemical filtration...

  3. AUTOMOTIVE AND HEAVY-DUTY ENGINE COOLANT RECYCLING BY DISTILLATION

    Science.gov (United States)

    This evaluation addresses the product quality, waste reduction, and economic issues involved in recycling automotive and heavy-duty engine coolants for a facility such as the New Jersey Department of Transportation garage in Ewing, New Jersey. he specific recycling evaluated is b...

  4. System and method for conditioning intake air to an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  5. Coolant Design System for Liquid Propellant Aerospike Engines

    Science.gov (United States)

    McConnell, Miranda; Branam, Richard

    2015-11-01

    Liquid propellant rocket engines burn at incredibly high temperatures making it difficult to design an effective coolant system. These particular engines prove to be extremely useful by powering the rocket with a variable thrust that is ideal for space travel. When combined with aerospike engine nozzles, which provide maximum thrust efficiency, this class of rockets offers a promising future for rocketry. In order to troubleshoot the problems that high combustion chamber temperatures pose, this research took a computational approach to heat analysis. Chambers milled into the combustion chamber walls, lined by a copper cover, were tested for their efficiency in cooling the hot copper wall. Various aspect ratios and coolants were explored for the maximum wall temperature by developing our own MATLAB code. The code uses a nodal temperature analysis with conduction and convection equations and assumes no internal heat generation. This heat transfer research will show oxygen is a better coolant than water, and higher aspect ratios are less efficient at cooling. This project funded by NSF REU Grant 1358991.

  6. Hot Air Engines

    OpenAIRE

    P. Stouffs

    2011-01-01

    Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of...

  7. Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement

    Science.gov (United States)

    Lundin, Bruce T; Povolny, John H; Chelko, Louis J

    1949-01-01

    Data obtained from an extensive investigation of the cooling characteristics of four multicylinder, liquid-cooled engines have been analyzed and a correlation of both the cylinder-head temperatures and the coolant heat rejections with the primary engine and coolant variables was obtained. The method of correlation was previously developed by the NACA from an analysis of the cooling processes involved in a liquid-cooled-engine cylinder and is based on the theory of nonboiling, forced-convection heat transfer. The data correlated included engine power outputs from 275 to 1860 brake horsepower; coolant flows from 50 to 320 gallons per minute; coolants varying in composition from 100 percent water to 97 percent ethylene glycol and 3 percent water; and ranges of engine speed, manifold pressure, carburetor-air temperature, fuel-air ratio, exhaust-gas pressure, ignition timing, and coolant temperature. The effect on engine cooling of scale formation on the coolant passages of the engine and of boiling of the coolant under various operating conditions is also discussed.

  8. Diesel engine coolant analysis, new application for established instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.P.; Lukas, M.; Lynch, B.K. [Spectro Incorporated, Littleton, MA (United States)

    1997-12-31

    Rotating disk electrode (RDE) arc emission spectrometers are user` many commercial, industrial and military laboratories throughout the world to analyze millions of oil and fuel samples each year. In fact, RDE spectrometers have been used exclusively for oil and fuel analysis for so long that it has nearly been forgotten by most practitioners that when RDE spectrometers were first introduced more than 40 years ago, they were routinely used for aqueous samples as well. This presentation reviews early methods of aqueous sample analysis using RDE technology. This presentation also describes recent work to calibrate an RDE spectrometer for both water samples and for engine coolant samples which are a mixture of approximately 50 % water and 50 % ethylene or propylene glycol. Limits of detection determined for aqueous standards are comparable to limits of detection for oil standards. Repeatability of aqueous samples is comparable to the repeatability achieved for oil samples. A comparison of results for coolant samples measured by both inductively coupled plasma (ICP) and rotating disk electrode (RDE) spectrometers is presented. Not surprisingly, RDE results are significantly higher for samples containing particles larger than a few micrometers. Although limits of detection for aqueous samples are not as low as can be achieved using the more modern ICP spectrometric method or the more cumbersome atomic absorption (AA) method, this presentation suggests that RDE spectrometers may be appropriate for certain types of aqueous samples in situations where the more sensitive ICP or AA spectrometers and the laboratory environment and skilled personnel needed for them to operate are not conveniently available. (orig.) 4 refs.

  9. Hot Air Engines

    Directory of Open Access Journals (Sweden)

    P. Stouffs

    2011-01-01

    Full Text Available Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of micro-combined heat and power, solar energy conversion and biomass energy conversion. The design of an open cycle Ericsson engine for solar application is proposed. A first prototype of the hot part of the engine has been built and tested. Experimental results are presented.

  10. An approach for IC engine coolant energy recovery based on low-temperature organic Rankine cycle

    Institute of Scientific and Technical Information of China (English)

    付建勤; 刘敬平; 徐政欣; 邓帮林; 刘琦

    2015-01-01

    To promote the fuel utilization efficiency of IC engine, an approach was proposed for IC engine coolant energy recovery based on low-temperature organic Rankine cycle (ORC). The ORC system uses IC engine coolant as heat source, and it is coupled to the IC engine cooling system. After various kinds of organic working media were compared, R124 was selected as the ORC working medium. According to IC engine operating conditions and coolant energy characteristics, the major parameters of ORC system were preliminary designed. Then, the effects of various parameters on cycle performance and recovery potential of coolant energy were analyzed via cycle process calculation. The results indicate that cycle efficiency is mainly influenced by the working pressure of ORC, while the maximum working pressure is limited by IC engine coolant temperature. At the same working pressure, cycle efficiency is hardly affected by both the mass flow rate and temperature of working medium. When the bottom cycle working pressure arrives at the maximum allowable value of 1.6 MPa, the fuel utilization efficiency of IC engine could be improved by 12.1%. All these demonstrate that this low-temperature ORC is a useful energy-saving technology for IC engine.

  11. Effects of anti-freeze concentration in the engine coolant on the cavitation temperature of a water pump

    International Nuclear Information System (INIS)

    Improvements in engine-manufacturing technology have gradually increased the thermal efficiencies of engines as well as the burning temperature and pressure of fuels within the cylinders. Accordingly, greater heat dissipation are required. However, the volume of the radiators is constrained by the configuration of the engines, leading to excessive internal resistance in the engine-cooling system. Therefore, water pumps in engines are prone to cavitation, and air bubbles are likely to permeate into the anti-freeze, thereby severely reducing the performance, reliability and service life of the engines. Ethylene glycol (EG) is added to the radiator of some vehicles in cold areas to reduce the solidification point of the coolant and prevent freezing. This study probes the effects of the percentage of anti-freeze added to the cooling water in a water pump in an engine on the water-supply capability and cavitation temperature, whether air or burnt gas is present in the system. The results of this study have revealed that engines have a higher tolerance to air bubbles at lower rates of rotation. At a given fixed rotational speed, the tolerable cavitation temperature of an engine's water pump will fall slowly as the amount of air bubbles increases

  12. Liquid air cycle engines

    Science.gov (United States)

    Rosevear, Jerry

    1992-01-01

    Given here is a definition of Liquid Air Cycle Engines (LACE) and existing relevant technologies. Heat exchanger design and fabrication techniques, the handling of liquid hydrogen to achieve the greatest heat sink capabilities, and air decontamination to prevent heat exchanger fouling are discussed. It was concluded that technology needs to be extended in the areas of design and fabrication of heat exchangers to improve reliability along with weight and volume reductions. Catalysts need to be improved so that conversion can be achieved with lower quantities and lower volumes. Packaging studies need to be investigated both analytically and experimentally. Recycling with slush hydrogen needs further evaluation with experimental testing.

  13. Environmentally acceptable and light metal neutral coolant additives for modern internal combustion engines. Modern coolant additives - final report; Umwelt- und leichtmetallvertraegliche Kuehlmittelzusaetze fuer moderne Verbrennungskraftmaschinen. Moderne Kuehlmittelzusaetze - Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Berger, C.; Gugau, M. [Technische Univ. Darmstadt (DE). Inst. fuer Werkstoffkunde (IFW); Kaiser, M.; Sausen, E. [Daimler Chrysler AG, Stuttgart (Germany)

    2004-07-01

    This project aims at researching environmentally and light metal compatible coolant additives of modern combustion engines and validating for the operational application. The main research divides into two category groups. On the one hand the further development of conventional engine concepts on basis of aluminium and cast iron materials (for car, truck and high-power engines) is to be considered. Because the capability raise in combination with an increase of combustion efficiency necessitates a better corrosion prevention stability of coolant additives to higher temperatures. In addition the reduction of coolant volume in smaller radiators with new materials of material combinations intensifies the necessity of thermal stability and the stretch of corrosion prevention. Otherwise the application of magnesium alloys is made possible for construction units for example crankcase or cylinder head that are contacted with coolant fluid in the future. Because of the considerably higher corrodibility of magnesium alloys it is necessary to examine the specific anticorrosion concepts of coolant additives. Thereby the process of corrosion prevention to magnesium and the stimulant activation of individual inhibitors to other materials of the engine take centre stage. Both intentions are closely involved with the requirement that the anticorrosion additives of cooling fluids for all engine concepts are to be evaluated under changed criteria for toxicological/ecological reasons. (orig.)

  14. Integral Test and Engineering Analysis of Coolant Depletion During a Large-Break Loss-of-Coolant Accident

    International Nuclear Information System (INIS)

    This study concerns the development of an integrated calculation methodology with which to continually and consistently analyze the progression of an accident from the design-basis accident phase via core uncovery to the severe accident phase. The depletion rate of reactor coolant inventory was experimentally investigated after the safety injection failure during a large-break loss-of-coolant accident utilizing the Seoul National University Integral Test Facility (SNUF), which is scaled down to 1/6.4 in length and 1/178 in area from the APR1400 [Advanced Power Reactor 1400 MW(electric)]. The experimental results showed that the core coolant inventory decreased five times faster before than after the extinction of sweepout in the reactor downcomer, which is induced by the incoming steam from the intact cold legs. The sweepout occurred on top of the spillover from the downcomer region and expedited depletion of the core coolant inventory. The test result was simulated with the MAAP4 severe accident analysis code. The calculation results of the original MAAP4 deviated from the test data in terms of coolant inventory distribution in the test vessel. After the calculation algorithm of coolant level distribution was improved by including the subroutine of pseudo pressure buildup, which accounts for the differential pressure between the core and downcomer in MAAP4, the core melt progression was delayed by hundreds of seconds, and the code prediction was in reasonable agreement with the overall behavior of the SNUF experiment

  15. An air flow simulating test in the coolant channel of the core bottom of the 10 MW HTGR module

    International Nuclear Information System (INIS)

    In order to investigate the efficiency of the thermal mixing of the coolant helium in the coolant channel of the core bottom and the hot gas duct, an air flow test has been performed on a scale of 1 to 1.5 analogical simulating test model. The test facility and the test are described. The results of the simulating test indicate that the coolant channel designed in the core bottom reflector and the hot gas duct of the HTR-test module possesses very good function of the coolant thermal mixing and can yield a non-dimensional temperature mixing degree of more than 98% and an uniformity of thermal distribution of over 99% at the exit of the hot gas duct

  16. Air-Breathing Rocket Engines

    Science.gov (United States)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  17. Thermal conductivity and viscosity of Al2O3 nanofluid based on car engine coolant

    International Nuclear Information System (INIS)

    Various suspensions containing Al2O3 nanoparticles (2O3 nanoparticles as well as temperature between 10 and 80 0C. The prepared nanofluid, containing only 0.035 volume fraction of Al2O3 nanoparticles, displays a fairly higher thermal conductivity than the base fluid and a maximum enhancement (knf/kbf) of ∼10.41% is observed at room temperature. The thermal conductivity enhancement of the Al2O3 nanofluid based on engine coolant is proportional to the volume fraction of Al2O3. The volume fraction and temperature dependence of the thermal conductivity of the studied nanofluids present excellent correspondence with the model proposed by Prasher et al (2005 Phys. Rev. Lett. 94 025901), which takes into account the role of translational Brownian motion, interparticle potential and convection in fluid arising from Brownian movement of nanoparticles for thermal energy transfer in nanofluids. Viscosity data demonstrate transition from Newtonian characteristics for the base fluid to non-Newtonian behaviour with increasing content of Al2O3 in the base fluid (coolant). The data also show that the viscosity increases with an increase in concentration and decreases with an increase in temperature. An empirical correlation of the type log(μnf) = A exp(-BT) explains the observed temperature dependence of the measured viscosity of Al2O3 nanofluid based on car engine coolant. We further confirm that Al2O3 nanoparticle concentration dependence of the viscosity of nanofluids is very well predicted on the basis of a recently reported theoretical model (Masoumi et al 2009 J. Phys. D: Appl. Phys. 42 055501), which considers Brownian motion of nanoparticles in the nanofluid.

  18. Modern coolant additives. Environmental friendly and light metal compatible coolant additives for modern combustion engines; Moderne Kuehlmittelzusaetze. Umwelt- und leichtmetallvertraegliche Kuehlmittelzusaetze fuer moderne Verbrennungskraftmaschinen. Abschlussbericht. Vorhaben Nr. 777

    Energy Technology Data Exchange (ETDEWEB)

    Gugau, M.; Kaiser, M.

    2004-01-31

    The authors of the contribution under consideration report on the influence of the enhanced thermal stress on the impact of environmental friendly and light metal compatible coolant additives. The application and advancement of new research methods under mechanism-oriented objective led to a validation of a new guideline to the examination of the suitability of coolant additives for the coolant of internal combustion engines. Moreover, the authors create a knowledge base, on which a purposeful development can take place from suitable formulations of inhibitor for magnesium. For aluminium with silicate containing corrosion anti-freezes a close relationship between the surface temperature and the impoverishment of silicate exists. During the excess of limit temperatures, cooling agent-specific damage features arise reproducibly. The comparison of the different methods for the investigation of cavitation showed that one cannot dispense with both methods in order to evaluate a demand of insulating cavitation and a cavitative / corrosive complex regarding to the development of a test guideline. By the comprehensive electro-chemical and cavitative investigations for the magnesium alloy AZ91hp, a broad knowledge base could be formed, on which a purposeful development and evaluation of inhibitors under the use can take place from different glycols.

  19. Electronically Controlling the System of Preheating Intake Air by Flame for Diesel Engine Cold-Start

    Institute of Scientific and Technical Information of China (English)

    杜巍; 赵福堂

    2003-01-01

    In order to improve the cold-start performance of heavy duty diesel engine, electronically controlling the preheating of intake air by flame was researched. According to simulation and thermodynamic analysis about the partial working processes of the diesel engine, the amount of heat energy, enough to make the fuel self-ignite at the end of compression process at different temperatures of coolant and intake-air, was calculated. Several HY20 preheating plugs were used to heat up the intake air. Meanwhile, an electronic control system based on 8 bit micro-controller unit (MCS-8031) was designed to automatically control the process of heating intake air. According to the various temperatures of coolant and ambient air, one plug or two plugs can automatically be selected to heat intake air. The demo experiment validated that the total system could operate successfully and achieve the scheduled function.

  20. Generic evaluation of feedwater transients and small break loss-of-coolant accidents in combustion engineering designed operating plants

    International Nuclear Information System (INIS)

    The purpose of this report is to summarize the results of a generic evaluation of feedwater transients, small break loss-of-coolant accidents (LOCAs), and other TMI-2-related events in the Combustion Engineering (CE)-designed operating plants and to establish or confirm the bases for their continued operation. The results of this evaluation are presented in this report in the form of a set of findings and recommendations in each of the principal review areas

  1. UO2 and PuO2 utilization in high temperature engineering test reactor with helium coolant

    Science.gov (United States)

    Waris, Abdul; Aji, Indarta K.; Novitrian, Pramuditya, Syeilendra; Su'ud, Zaki

    2016-03-01

    High temperature engineering test reactor (HTTR) is one of high temperature gas cooled reactor (HTGR) types which has been developed by Japanese Atomic Energy Research Institute (JAERI). The HTTR is a graphite moderator, helium gas coolant, 30 MW thermal output and 950 °C outlet coolant temperature for high temperature test operation. Original HTTR uses UO2 fuel. In this study, we have evaluated the use of UO2 and PuO2 in form of mixed oxide (MOX) fuel in HTTR. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. The result shows that HTTR can obtain its criticality condition if the enrichment of 235U in loaded fuel is 18.0% or above.

  2. New Hydrophilic, Composite Membranes for Air Removal from Water Coolant Systems

    Science.gov (United States)

    Ritchie, Stephen M. C.; Luo, Qiang; Curtis, Salina S.; Holladay, Jon B.; Clark, Dallas W.

    2004-01-01

    Liquid coolants are commonly used as thermal transport media to increase efficiency and flexibility in aerospace vehicle design. The introduction of gas bubbles into the coolant can have negative consequences, including: loss of centrifugal pump prime, irregular sensor readings, and blockage of coolant flow to remote systems. One solution to mitigate these problems is the development of a passive gas removal device, or gas trap, installed in the flight cooling system. In this study, a new hydrophilic, composite membrane has been developed for passage of the coolant fluid and retention of gas bubbles. The trapped bubbles are subsequently vented from the system by a thin, hydrophobic, microporous membrane. The original design for this work employed a homogeneous membrane that was susceptible to fouling and pore plugging. Spare gas traps of this variety have degraded during storage, and recreation of the membranes has been complicated due to problems with polymer duplication and property variations in the final membranes. In this work, replacements have been developed based on deposition of a hydrophilic polymer on the bore-side of a porous polyethylene (PE) tube. The tube provides excellent chemical and mechanical stability, and the hydrophilic layer provides retention of gas bubbles. Preliminary results have shown that intimate contact is required between the deposited layer and the substrate to overcome material differences. This has been accomplished by presoaking the membrane tube in the solvent to raise its surface energy. Polymer solutions of various concentrations have been used to promote penetration of the polymer layer into the porous substrate and to control separation layer thickness. The resulting composite membranes have shown repeatable decrease in nitrogen permeability, which is indicative of a decrease in membrane pore size. Studies with water permeation have yielded similar results. We have observed some swelling of the added polymer layer, which

  3. The high-temperature sodium coolant technology in nuclear power installations for hydrogen power engineering

    Science.gov (United States)

    Kozlov, F. A.; Sorokin, A. P.; Alekseev, V. V.; Konovalov, M. A.

    2014-05-01

    In the case of using high-temperature sodium-cooled nuclear power installations for obtaining hydrogen and for other innovative applications (gasification and fluidization of coal, deep petroleum refining, conversion of biomass into liquid fuel, in the chemical industry, metallurgy, food industry, etc.), the sources of hydrogen that enters from the reactor plant tertiary coolant circuit into its secondary coolant circuit have intensity two or three orders of magnitude higher than that of hydrogen sources at a nuclear power plant (NPP) equipped with a BN-600 reactor. Fundamentally new process solutions are proposed for such conditions. The main prerequisite for implementing them is that the hydrogen concentration in sodium coolant is a factor of 100-1000 higher than it is in modern NPPs taken in combination with removal of hydrogen from sodium by subjecting it to vacuum through membranes made of vanadium or niobium. Numerical investigations carried out using a diffusion model showed that, by varying such parameters as fuel rod cladding material, its thickness, and time of operation in developing the fuel rods for high-temperature nuclear power installations (HT NPIs) it is possible to exclude ingress of cesium into sodium through the sealed fuel rod cladding. However, if the fuel rod cladding loses its tightness, operation of the HT NPI with cesium in the sodium will be unavoidable. Under such conditions, measures must be taken for deeply purifying sodium from cesium in order to minimize the diffusion of cesium into the structural materials.

  4. 40 CFR 91.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  5. 14 CFR 23.1111 - Turbine engine bleed air system.

    Science.gov (United States)

    2010-01-01

    ... using maximum bleed air must be established. (c) Hazardous contamination of cabin air systems may not... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine bleed air system. 23.1111... Induction System § 23.1111 Turbine engine bleed air system. For turbine engine bleed air systems,...

  6. Fundamentals of air pollution engineering

    OpenAIRE

    Flagan, Richard C.; Seinfeld, John H.

    1988-01-01

    Analysis and abatement of air pollution involve a variety of technical disciplines. Formation of the most prevalent pollutants occurs during the combustion process, a tightly coupled system involving fluid flow, mass and energy transport, and chemical kinetics. Its complexity is exemplified by the fact that, in many respects, the simplest hydrocarbon combustion, the methane-oxygen flame, has been quantitatively modeled only within the last several years. Nonetheless, the development of combus...

  7. Investigation of chemical characteristics of primary helium gas coolant of HTTR (high temperature engineering test reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Hamamoto, Shimpei, E-mail: hamamoto.shimpei@jaea.go.jp [HTTR Operation Section, Department of HTTR, Japan Atomic Energy Agency, 4002 Narita, Oarai, Higashi-ibaraki, Ibaraki 311-1393 (Japan); Shimazaki, Yosuke [HTTR Reactor Engineering Section, Department of HTTR, Japan Atomic Energy Agency, 4002 Narita, Oarai, Higashi-ibaraki, Ibaraki 311-1393 (Japan); Furusawa, Takayuki; Nemoto, Takahiro; Inoi, Hiroyuki [HTTR Operation Section, Department of HTTR, Japan Atomic Energy Agency, 4002 Narita, Oarai, Higashi-ibaraki, Ibaraki 311-1393 (Japan); Takada, Shoji, E-mail: takada.shoji@jaea.go.jp [HTTR Reactor Engineering Section, Department of HTTR, Japan Atomic Energy Agency, 4002 Narita, Oarai, Higashi-ibaraki, Ibaraki 311-1393 (Japan)

    2014-05-01

    The technical basis of helium gas purification control for HTGRs was established by verifying the design of the Primary Helium Purification System (PHPS) of the HTTR by showing that the measured concentrations of impurities of the primary helium coolant were restricted below the criteria of control to protect the graphite oxidation, and that the carburization atmosphere was maintained to keep intact of metallic high temperature components, in the 30-day continuous operation and the 50-day long-term high temperature operation. The analytical model, which was newly established by improving the conventional method that predicted the impurity concentrations conservatively higher than the measured values, predicted the composition of the impurities such as H{sub 2}, CO, H{sub 2}O and CO{sub 2}, which is determined by the temperature dependency of release of impurities during the rated power operation adequately. In contrast, it was revealed that the measured concentration of H{sub 2}O remarkably decreased while the concentration of CO increased in the primary helium coolant in the long-term high temperature operation.

  8. Investigation of chemical characteristics of primary helium gas coolant of HTTR (high temperature engineering test reactor)

    International Nuclear Information System (INIS)

    The technical basis of helium gas purification control for HTGRs was established by verifying the design of the Primary Helium Purification System (PHPS) of the HTTR by showing that the measured concentrations of impurities of the primary helium coolant were restricted below the criteria of control to protect the graphite oxidation, and that the carburization atmosphere was maintained to keep intact of metallic high temperature components, in the 30-day continuous operation and the 50-day long-term high temperature operation. The analytical model, which was newly established by improving the conventional method that predicted the impurity concentrations conservatively higher than the measured values, predicted the composition of the impurities such as H2, CO, H2O and CO2, which is determined by the temperature dependency of release of impurities during the rated power operation adequately. In contrast, it was revealed that the measured concentration of H2O remarkably decreased while the concentration of CO increased in the primary helium coolant in the long-term high temperature operation

  9. Long-term security of electrical and control engineering equipment in nuclear power stations to withstand a loss of coolant accident

    International Nuclear Information System (INIS)

    Electrical and control engineering equipment, which has to function even after many years of operation in the event of a fault in a saturated steam atmosphere of 160 C maximum, is essential in nuclear power stations in order to control a loss of coolant accident. The nuclear power station operators have, for this purpose, developed verification strategies for groups of components, by means of which it is ensured that the electrical and control engineering components are capable of dealing with a loss of coolant accident even at the end of their planned operating life. (orig.)

  10. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    Science.gov (United States)

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  11. Piston slap induced pressure fluctuation in the water coolant passage of an internal combustion engine

    Science.gov (United States)

    Ohta, Kazuhide; Wang, Xiaoyu; Saeki, Atsushi

    2016-02-01

    Liner cavitation is caused by water pressure fluctuation in the water coolant passage (WCP). When the negative pressure falls below the saturated vapor pressure, the impulsive pressure following the implosion of cavitation bubbles causes cavitation erosion of the wet cylinder liner surface. The present work establishes a numerical model for structural-acoustic coupling between the crankcase and the acoustic field in the WCP considering their dynamic characteristics. The coupling effect is evaluated through mutual interaction terms that are calculated from the mode shapes of the acoustic field and of the crankcase vibration on the boundary. Water pressure fluctuations in the WCP under the action of piston slap forces are predicted and the contributions of the uncoupled mode shapes of the crankcase and the acoustic field to the pressure waveform are analyzed. The influence of sound speed variations on the water pressure response is discussed, as well as the pressure on the thrust sides of the four cylinders.

  12. Engine piston having an insulating air gap

    Science.gov (United States)

    Jarrett, Mark Wayne; Hunold,Brent Michael

    2010-02-02

    A piston for an internal combustion engine has an upper crown with a top and a bottom surface, and a lower crown with a top and a bottom surface. The upper crown and the lower crown are fixedly attached to each other using welds, with the bottom surface of the upper crown and the top surface of the lower crown forming a mating surface. The piston also has at least one centrally located air gap formed on the mating surface. The air gap is sealed to prevent substantial airflow into or out of the air gap.

  13. Air-breathing Rocket Engine Test

    Science.gov (United States)

    1999-01-01

    This Quick Time movie depicts the Rocketdyne static test of an air-breathing rocket. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's advanced Transportation Program at the Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  14. 40 CFR 91.310 - Engine intake air humidity measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  15. 40 CFR 89.325 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  16. PERFORMANCE EVALUATION AND EMISSION CHARACTERISTICS OF LOW HEAT REJECTION ENGINE USING AIR GAP INSULATION

    Directory of Open Access Journals (Sweden)

    M. IRSHAD AHMED

    2013-06-01

    Full Text Available It is well known fact that about 30% of the energy supplied is lost through the coolant and the 30% is wasted through friction and other losses, thus leaving only about 30% of energy utilization for useful purposes. In view of the above, the major thrust in engine research during the last two decades has been on the development of low heat rejection engines. The Low Heat Rejection (LHR engine has been given considerable attention recently as engine builders struggle to find remaining avenues to improve economy and lower emissions. The concept of air gap insulated piston has been explored by providing 1mm air gap within the piston by using bolted type piston. The bolted air gapinsulated piston provides complete sealing of air gap necessary for continued insulation. The design evolved provides high insulation combining adequate durability. In order to provide high insulation andreliability, proper designing of the air gap piston has to be ensured. The piston with 1mm thickness of air gap are designed with two different material. The insulation provides betterment in fuelconsumption at normal operating condition than a conventional piston engine and also the delay period tends to reduce the emissions levels of Hydrocarbons and carbon monoxide. The combustion rate is increased because of insulation and hence there is reduced vibration and noise level.

  17. Air-Breathing Rocket Engine Test

    Science.gov (United States)

    2000-01-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  18. 40 CFR 89.326 - Engine intake air humidity measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  19. History of the hot-air engines

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, S.

    1982-01-01

    It cannot be exactly determined any more who had first invented or built a hot-air engine and when that was, for many people had dealt with the development of power engines at the beginning of the 19th century. Also the documentation and patents systems had been rather underdeveloped or had not even existed yet. There was hardly any exchange of experiences or communication beyond the national boundaries. Consequently it can be assumed that similar machines were built simultaneously but independently of each other in many countries. However, almost all those machines and methods have fallen into oblivion within the course of time.

  20. LOFA [loss of flow accident] and LOCA [loss of coolant accident] in the TIBER-II engineering test reactor: Appendix A-4

    International Nuclear Information System (INIS)

    This paper describes the preliminary analysis of LOFA (loss of flow accident) and LOCA (loss of coolant accident) in the TIBER-II engineering test reactor breeding shield. TIBER-II is a compact reactor with a major radius of 3 m and thus requires a thin, high efficiency shield on the inboard side. The use of tungsten in the inboard shield implies a rather high rate of afterheat upon plasma shutdown, which must be dissipated in a controlled manner to avoid the possibility of radioactivity release or threatening the investment. Because the shield is cooled with an aqueous solution, LOFA does not pose a problem as long as natural convection can be established. LOCA, however, has more serious consequences, particularly on the inboard side. Circulation of air by natural convection is proposed as a means for dissipating the inboard shield decay heat. The safety and environmental implications of such a scheme are evaluated. It is shown that the inboard shield temperature never exceeds 5100C following LOCA posing no hazard to reactor personnel and not threatening the investment. 7 refs., 6 figs

  1. Synthesis of ethylene glycol-treated Graphene Nanoplatelets with one-pot, microwave-assisted functionalization for use as a high performance engine coolant

    International Nuclear Information System (INIS)

    Highlights: • A potentially mass production method is introduced for preparing EG-treated GNP. • A promising car radiator coolant in the presence of neutral media synthesized. • Car engine can work in lower temperature via high-performance coolant. • The ratio of convective to conductive heat transfer is unique. • New economical product with high performance index is introduced. - Abstract: An electrophilic addition reaction under microwave irradiation was developed as a promising, quick and cost-effective approach to functionalize Graphene Nanoplatelets (GNP) with ethylene glycol (EG). EG-treated GNP was synthesized to reach a promising dispersibility in the water–EG media without negative effects of acid-treatment. Surface functionality groups and the morphology of chemically-functionalized GNP were characterized by the vibration spectroscopies, temperature-programmed study, and microscopic method. Despite the fact that the main structures of GNP were remained reasonably intact, characterization results consistently verified the functionalization of GNP with EG functionalities. As new kinds of high-performance engine coolant, the EG-treated GNP based water–EG coolant (GNP-WEG) was prepared and its thermo-physical and rheological properties are evaluated. In particular, the thermal conductivity, viscosity, specific heat capacity, and density of all samples were experimentally measured to evaluate the thermal performance of the GNP-WEG coolant. The data showed insignificant increases in the pressure drop at different temperatures and concentrations, low friction factor, lack of corrosive condition, and the performance index larger than 1. In addition, no momentous change in the pumping power in the presence of GNP-WEG confirmed that it can be an appropriate alternative coolant for different thermal equipment in terms of economy and performance

  2. 40 CFR 1065.125 - Engine intake air.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the...

  3. 40 CFR 90.310 - Engine intake air humidity measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  4. Monitoring coolant

    International Nuclear Information System (INIS)

    In a system for monitoring coolant conditions within a pressurized vessel, a length of tubing extends outward from the vessel from an open end containing a first liner restriction at the location to be monitored. The flowing fluid is cooled and condensed before passing through a second line restriction. Measurement of pressure drop at the second line restriction gives an indication of fluid condition at the first line restriction. Multiple lengths of tubing with open ends at incremental elevations can measure coolant level within the vessel. The system may monitor the coolant level within the vessel and also provide measurement of the gaseous phase material at the monitored location and of the temperature of the liquid coolant or of superheated vapors. (author)

  5. Using the technology of ship reactors with a liquid-metal coolant in the civil nuclear power engineering of Russia

    International Nuclear Information System (INIS)

    One analyzes possibility to apply ship reactors with Pb-Bi coolant in civil nuclear power plants of Russia. Renovation of NPP units with Pb-Bi coolant reactor modulus is shown to be one of the most economically efficient ways to replace decommissioned capacities. The elaborated renovation of the Novo-Voronezh NPP old power units demonstrates that this option rules out most severe accidents

  6. Deployable Engine Air-Brake for Drag Management Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc, proposes an SBIR program to demonstrate an innovative engine air-brake (EAB) technology that uses a deployable swirl vane mechanism to switch...

  7. Deployable Engine Air-Brake for Drag Management Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc., (ATA) proposes a Phase II SBIR program to demonstrate an innovative engine air-brake (EAB) technology that uses a deployable swirl vane...

  8. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    OpenAIRE

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design c...

  9. 40 CFR 90.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  10. Comparison of the externally heated air valve engine and the helium Stirling engine

    International Nuclear Information System (INIS)

    Highlights: • Air EHVE produces comparable power as equivalent helium Stirling engine. • No heat regenerator used in the EHVE, standard lubrication system. • External combustion engine combined with forced flow added (super-charging). • EHVE uses typical piston engine body design and governing cam system. • Possible use of different fuels: oil, coal, gas also sun and nuclear energy. - Abstract: A two-stroke, externally heated valve engine (EHVE) with a heater, a cooler and two blowers is simulated. The engine is entirely different from a typical Stirling engine. The pressure ratio pmax/pmin of its cycle is higher, but the engine volume and the mean value of the heat exchanger wall temperatures are the same. The power and efficiency of the EHVE and Stirling engines under the same maximum pressures are compared. The results show that the EHVE engine reaches almost the same level of performance as the Stirling engine, while using only available atmospheric air, rather than helium

  11. Air intake and exhaust systems in fuel cell engines

    Energy Technology Data Exchange (ETDEWEB)

    Fuesser, R.; Weber, O. [Mann and Hummel (Germany)

    1999-07-01

    This paper describes the design and development of the air intake and exhaust system of a fuel cell powered road vehicle. In this instance the automotive supplier designed both the air intake and the exhaust system. The fuel cell engine gives a cold combustion effect making it possible to manufacture the exhaust from plastic materials. (UK)

  12. EXPERIMENTAL INVESTIGATION OF AN AIR CHARGED LOW POWERED STIRLING ENGINE

    Directory of Open Access Journals (Sweden)

    Can ÇINAR

    2004-01-01

    Full Text Available In this study, an air charged, low powered manufactured ? type Stirling engine was investigated experimentally. Tests were conducted at 800, 900 and 1000 °C hot source temperatures, 1, 1.5, 2, 2.5, 3, 3.5 bars air charge pressure. The variation of engine power depending on the charge pressure and hot source temperature for two different heat transfer area was investigated experimentally. Maximum output power was obtained at 1000 °C and 3 bars charge pressure as 58 W at 441 rpm. Engine speed was reached at 846 rpm without load.

  13. EXPERIMENTAL INVESTIGATION OF AN AIR CHARGED LOW POWERED STIRLING ENGINE

    OpenAIRE

    Can ÇINAR

    2004-01-01

    In this study, an air charged, low powered manufactured ? type Stirling engine was investigated experimentally. Tests were conducted at 800, 900 and 1000 °C hot source temperatures, 1, 1.5, 2, 2.5, 3, 3.5 bars air charge pressure. The variation of engine power depending on the charge pressure and hot source temperature for two different heat transfer area was investigated experimentally. Maximum output power was obtained at 1000 °C and 3 bars charge pressure as 58 W at 441 rpm. Engine speed w...

  14. Computer Model to Estimate Reliability Engineering for Air Conditioning Systems

    International Nuclear Information System (INIS)

    Reliability engineering is used to predict the performance and optimize design and maintenance of air conditioning systems. Air conditioning systems are expose to a number of failures. The failures of an air conditioner such as turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply and loss of air flow entirely can be due to a variety of problems with one or more components of an air conditioner or air conditioning system. Forecasting for system failure rates are very important for maintenance. This paper focused on the reliability of the air conditioning systems. Statistical distributions that were commonly applied in reliability settings: the standard (2 parameter) Weibull and Gamma distributions. After distributions parameters had been estimated, reliability estimations and predictions were used for evaluations. To evaluate good operating condition in a building, the reliability of the air conditioning system that supplies conditioned air to the several The company's departments. This air conditioning system is divided into two, namely the main chilled water system and the ten air handling systems that serves the ten departments. In a chilled-water system the air conditioner cools water down to 40-45 degree F (4-7 degree C). The chilled water is distributed throughout the building in a piping system and connected to air condition cooling units wherever needed. Data analysis has been done with support a computer aided reliability software, this is due to the Weibull and Gamma distributions indicated that the reliability for the systems equal to 86.012% and 77.7% respectively. A comparison between the two important families of distribution functions, namely, the Weibull and Gamma families was studied. It was found that Weibull method performed for decision making.

  15. A Mobile Air Conditioning System Operated by the Engine Waste Heat

    Energy Technology Data Exchange (ETDEWEB)

    Magnetto, D. [Centro Ricerche FIAT, Turin (Italy); De Boer, R. [ECN Efficiency and Infrastructure, Petten (Netherlands); Taklanti, A. [Valeo Systemes Thermiques SAS, Paris (France)

    2011-04-12

    This paper describes the development of a Mobile Air Conditioning (MAC) system with a very small impact on the environment. The system based on adsorption cooling is powered by the waste heat recovered from the engine coolant. The advantages of such a system are: a drastic reduction of the fuel overconsumption and the CO2 emission associated to the MAC usage, and the use of water as the refrigerant, which is a no Global Warming Potential (GWP) fluid compliant with the new EU regulation and naturally available. In addition the system being based on thermal compression and not on mechanical compression, is decoupled from the engine operation and has no impact on the vehicle handling. Finally, coupled with a small fuel burner or with a solar panel it can provide air conditioning when the vehicle engine is stop. Thus the system can provide the cabin preconditioning and allows the cabin cooling for those vehicles which are also used for rest or sleeping (truck, camper). The core of the system is an adsorption chiller that has been designed, manufactured and tested at first at the ECN laboratory. It produces 2 kW of chilling power with a COP of 0,4. The on board overall MAC system has been designed, manufactured and installed on a Fiat Grande Punto at CRF. The tests demonstrate the potential of such device to replace conventional vapor compression system. Following this experimental work a system redesign and car integration study was done and showed the potential to further reduce the volume and weight of the adsorption cooling system to the extent that the system can be integrated fully in the engine compartment.

  16. Performance investigation of an automotive car radiator operated with nanofluid-based coolants (nanofluid as a coolant in a radiator)

    International Nuclear Information System (INIS)

    Water and ethylene glycol as conventional coolants have been widely used in an automotive car radiator for many years. These heat transfer fluids offer low thermal conductivity. With the advancement of nanotechnology, the new generation of heat transfer fluids called, 'nanofluids' have been developed and researchers found that these fluids offer higher thermal conductivity compared to that of conventional coolants. This study focused on the application of ethylene glycol based copper nanofluids in an automotive cooling system. Relevant input data, nanofluid properties and empirical correlations were obtained from literatures to investigate the heat transfer enhancement of an automotive car radiator operated with nanofluid-based coolants. It was observed that, overall heat transfer coefficient and heat transfer rate in engine cooling system increased with the usage of nanofluids (with ethylene glycol the basefluid) compared to ethylene glycol (i.e. basefluid) alone. It is observed that, about 3.8% of heat transfer enhancement could be achieved with the addition of 2% copper particles in a basefluid at the Reynolds number of 6000 and 5000 for air and coolant respectively. In addition, the reduction of air frontal area was estimated.

  17. A hot air driven thermoacoustic-Stirling engine

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, M.E.H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-09-15

    Significant energy savings can be obtained by implementing a thermally driven heat pump into industrial or domestic applications. Such a thermally driven heat pump uses heat from a high-temperature source to drive the system which upgrades an abundantly available heat source (industrial waste heat, air, water, geothermal). A way to do this is by coupling a thermoacoustic engine with a thermoacoustic heat pump. The engine is driven by a burner and produces acoustic power and heat at the required temperature. The acoustic power is used to pump heat in the heat pump to the required temperature. This system is attractive since it uses a noble gas as working medium and has no moving mechanical parts. This paper deals with the first part of this system: the engine. In this study, hot air is used to simulate the flue gases originating from a gas burner. This is in contrast with a lot of other studies of thermoacoustic engines that use an electrical heater as heat source. Using hot air resembles to a larger extent the real world application. The engine produces about 300W of acoustic power with a performance of 41% of the Carnot efficiency at a hot air temperature of 620C.

  18. Exergy Analysis of the Revolving Vane Compressed Air Engine

    OpenAIRE

    Alison Subiantoro; Kin Keong Wong; Kim Tiow Ooi

    2016-01-01

    Exergy analysis was applied to a revolving vane compressed air engine. The engine had a swept volume of 30 cm3. At the benchmark conditions, the suction pressure was 8 bar, the discharge pressure was 1 bar, and the operating speed was 3,000 rev·min−1. It was found that the engine had a second-law efficiency of 29.6% at the benchmark conditions. The contributors of exergy loss were friction (49%), throttling (38%), heat transfer (12%), and fluid mixing (1%). A parametric study was also conduct...

  19. Coolant technology experience in Russia

    International Nuclear Information System (INIS)

    In the early 1950s, the researches on substantiation of nuclear power facilities cooled with lead-bismuth eutectic alloy were started in Russia under the proposal made by A.I. Leipunsky. The choice of this alloy as a coolant was determined by its some positive physical-chemical thermal-physical properties. Low chemical activity of lead and bismuth at interaction of the alloy with air, water, steam excludes an opportunity of explosion and fire. The high level of coolant boiling temperature prevents an opportunity of its boiling in high power density parts of facility. The low working pressure in a coolant circuit increases a reliability and safety, simplifies a design and manufacturing of the equipment, essentially facilitates operational conditions of the equipment in the primary circuit

  20. An electrochemical engineering technique to improve the corrosion resistance of some structural materials in lead-alloy coolants

    International Nuclear Information System (INIS)

    The goal of this paper is to present some conclusions resulted from the literature studies referring to the materials potential to be used in Lead Fast Reactors (LFR), and the results obtained in the surface engineering field which can be used in our institute in order to obtain materials with appropriate properties for their use in LFR. In this context, the paper presents some preliminary results obtained in Surface Analysis Laboratory of INR Pitesti and research works in progress referring to: controlled modification of AISI 316L surface by electrochemical plasma treatment (carburization, nitrocarburizings); electrodeposition of some protective thin-films based on Ni and Al obtained from ionic liquids; development of some procedures related to the activities involved in the behaviour evaluation, in LFR specific conditions, for material samples subjected to treatments by surface engineering techniques using the LEad COrrosion TEsting LOop (LECOTELO) test bench. The superficial structures obtained have been characterized by metallographic microscopy, X-Ray Photoemission Spectroscopy (XPS), Electrochemical Impedance Spectroscopy (EIS); the electrochemical techniques were used to evaluate the corrosion behaviour. The preliminary results have shown that the used electrochemical surface engineering techniques are appropriate in order to improve the mechanical properties and corrosion behaviour of AISI 316L steel. (authors)

  1. Pollution prevention for cleaner air: EPA's air and energy engineering research laboratory

    International Nuclear Information System (INIS)

    The article discusses the role of EPA's Air and Energy Engineering Research Laboratory (AEERL) in pollution prevention research for cleaner air. For more than 20 years, AEERL has been conducting research to identify control approaches for the pollutants and sources which contribute to air quality problems. The Laboratory has successfully developed and demonstrated cost-effective sulfur dioxide, nitrogen oxides, and particulate control technologies for fossil fuel combustion sources. More recently, it has expanded its research activities to include indoor air quality, radon, organic control, stratospheric ozone depletion, and global warming. AEERL also develops inventories of air emissions of many types. Over the last several years, it has made substantial efforts to expand research on pollution prevention as the preferred choice for air emissions reduction

  2. Liquid air fueled open–closed cycle Stirling engine

    International Nuclear Information System (INIS)

    Highlights: • Energy of liquid air is divided into cryogenic energy and expansion energy. • Open–closed cycle Stirling mechanism is employed to improve efficiency. • The Schmidt theory is modified to describe temperature variation in cold space. - Abstract: An unconventional Stirling engine is proposed and its theoretical analysis is performed. The engine belongs to a “cryogenic heat engine” that is fueled by cryogenic medium. Conventional “cryogenic heat engine” employs liquid air as pressure source, but disregards its heat-absorbing ability. Therefore, its efficiency can only be improved by increasing vapor pressure, accordingly increasing the demand on pressure resistance and sealing. In the proposed engine, the added Stirling mechanism helps achieve its high efficiency and simplicity by utilizing the heat-absorbing ability of liquid air. On one hand, based on Stirling mechanism, gas in the hot space absorbs heat from atmosphere when expanding; gas in the cold space is cooled down by liquid air when compressed. Taking atmosphere as heat source and liquid air as heat sink, a closed Stirling cycle is formed. On the other hand, an exhaust port is set in the hot space. When expanding in the hot space, the vaporized gas is discharged through the exhaust port. Thus, an open cycle is established. To model and analyze the system, the Schmidt theory is modified to describe temperature variation in the cold space, and irreversible characteristic of regenerator is incorporated in the thermodynamic model. The results obtained from the model show that under the same working pressure, the efficiency of the proposed engine is potentially higher than that of conventional ones and to achieve the same efficiency, the working pressure could be lower with the new mechanism. Its efficiency could be improved by reducing temperature difference between the regenerator and the cold/hot space, increasing the swept volume ratio, decreasing the liquid–gas ratio. To keep

  3. Engine-driven hybrid air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    Chaokui QIN; Hongmei LU; Xiong LIU; Gerhard SCHMITZ

    2009-01-01

    A hybrid air-conditioning system that com-bines an engine-driven chiller with desiccant dehumidifi-cation was configured and experimentally tested to provide reliable data for energy consumption and operation cost. The engine performance and the desiccant wheel perfor-mance were measured and a numeric model previously set up for dehumidification capacity prediction was validated. For a reference building, the results based upon measured data show that under present electricity/gas price ratio, more than 40% of operation cost can be saved by the hybrid system.

  4. On modelling, mathematical analysis and numerical treatment of three-dimensional transient two-phase coolant flow in engineering systems

    International Nuclear Information System (INIS)

    The conservations equations of mass, momentum and enthalpy and the entropy inequality, written for a two-phase flow in the local instantaneous form together with the respective jump conditions at the phase interfaces, are volume-averaged over Eulerian control cells yielding a system of coupled macroscopic governing equations for the separated phases suitable for the three-dimensional, transient numerical simulation of complex engineering systems. The equations for the separated phases are then combined to model the fluid mixture in the frame of a slip model. The state of the art of the numerical treatment of the discretized and linearized equations is presented with reference to solution methods of a resulting Poisson-equation for pressure and enthalpy distributions. The above algorithms have been implemented in the computer programmes BACCHUS-3D/TP and COMMIX-2. The application of these codes is reviewed with reference to the numerical simulation of sodium boiling experiments in bundle geometry and of forced and natural convection simulations in more complex geometrical configurations. (author)

  5. Machine coolant recycling system

    International Nuclear Information System (INIS)

    Machining processes at the 272W Site Fabrication Services (SFS) produce a waste stream consisting of dirty machine coolant. During use the coolant becomes contaminated with metal chips from milling, and oil, dirt and solvents from the machining process. The mixture is designated as a Washington State dangerous waste with WP02 (persistence), D007 (chromium) and D008 (lead) waste codes. This process results in the generation of 13.5 m3 of hazardous waste per year with an annual cost for coolant replacement, waste management and waste disposal of approximately $137,000. To identify alternatives to this situation, ICF Kaiser Hanford Company (ICF KH) North Environmental Services conducted a pollution prevention opportunity assessment (P20A) on the machining processes. A coolant recycler and sump sucker unit were selected as the most cost-effective waste reduction options. In December 1994, ICF KH received return on investment (ROI) funding from the U.S. Department of Energy Richland Operations Office (DOE-RL) to implement this option. The coolant recycling and the sump sucker units were purchased and installed in July 1995 at a total cost of $61,000. The sump sucker removes the dirty coolant from the fabrication machinery and filters it to remove shavings and sludge. The filtered coolant then is transferred to the coolant recycling system for further processing. The coolant recycling system reconditions the filtered coolant for use in the machining equipment, and mixes the concentrated coolant to the correct concentration. As a result of implementing this option, the annual generation of waste coolant was reduced by 12 m3. The annual cost savings exceed $119,000 with an ROI of 186%. Additional benefits include reduced coolant usage; improved tool life, wheel life, finish, size control, corrosion protection, and operator working conditions; increase machine open-quotes up-timeclose quotes; and reduced machine tool maintenance

  6. HANARO secondary coolant management

    International Nuclear Information System (INIS)

    In this report, the basic theory for management of water quality, environmental factors influencing to the coolant, chemicals and its usage for quality control of coolant are mentioned, and water balance including the loss rate by evaporation (34.3 m3/hr), discharge rate (12.665 m3/hr), concentration ratio and feed rate (54.1 m3/hr) are calculated at 20 MW operation. Also, the analysis data of HANSU Limited for HANARO secondary coolant (feed water and circulating coolant) - turbidity, pH, conductivity, M-alkalinity, Ca-hardness, chloride ion, total iron ion, phosphoric ion and conversion rate are reviewed. It is confirmed that the feed water has good quality and the circulating coolant has been maintained within the control specification in general, but some items exceeded the control specification occasionally. Therefore it is judged that more regular discharge of coolant is needed. (author). 6 refs., 17 tabs., 18 figs

  7. Modelling internal air systems in gas turbine engines

    Institute of Scientific and Technical Information of China (English)

    J Michael Owen

    2007-01-01

    Rotating-disc systems can be used to model,experimentally and computationally,the flow and heat transfer that occur inside the internal cooling-air systems of gas turbine engines.These rotating-disc systems have been used successfully to simplify and understand some of the complex flows that occur in internal-air systems,and designers have used this insight to improve the cooling effectiveness,thereby increasing the engine efficiency and reducing the emissions.In this review paper,three important cases are considered:hot-gas ingress;the pre-swirl system;and buoyancy-induced flow.Ingress,or ingestion,occurs when hot gas from the mainstream gas path is ingested into the wheel-space between the turbine disc and its adjacent casing.Rim seals are fitted at the periphery of the system,and sealing flow is used to reduce or prevent ingress.However,too much sealing air reduces the engine efficiency,and too little can cause serious overheating,resulting in damage to the turbine rim and blade roots.Although the flow is three-dimensional and unsteady,there are encouraging signs that simple 'orifice models' could be used to estimate the amount of ingress into the wheel-space.In a pre-swirl system,the cooling air for the gas-turbine blades is swirled by stationary nozzles,and the air is delivered to the blades via receiver holes in the rotating turbine disc.Swirling the air reduces its temperature relative to the rotating blades,and the designer needs to calculate the air temperature and pressure drop in the system.The designer also needs to calculate the effect of this swirling flow on the heat transfer from the turbine disc to the air,as this has a significant effect on the temperature distribution and stresses in the disc.Recent experimental and computational studies have given a better understanding of the flow and heat transfer in these systems.Buoyancy-induced flow occurs in the cavity between two co-rotating compressor discs when the temperature of the discs is higher

  8. Evaluation of air pollution modelling tools as environmental engineering courseware.

    Science.gov (United States)

    Souto González, J A; Bello Bugallo, P M; Casares Long, J J

    2004-01-01

    The study of phenomena related to the dispersion of pollutants usually takes advantage of the use of mathematical models based on the description of the different processes involved. This educational approach is especially important in air pollution dispersion, when the processes follow a non-linear behaviour so it is difficult to understand the relationships between inputs and outputs, and in a 3D context where it becomes hard to analyze alphanumeric results. In this work, three different software tools, as computer solvers for typical air pollution dispersion phenomena, are presented. Each software tool developed to be implemented on PCs, follows approaches that represent three generations of programming languages (Fortran 77, VisualBasic and Java), applied over three different environments: MS-DOS, MS-Windows and the world wide web. The software tools were tested by students of environmental engineering (undergraduate) and chemical engineering (postgraduate), in order to evaluate the ability of these software tools to improve both theoretical and practical knowledge of the air pollution dispersion problem, and the impact of the different environment in the learning process in terms of content, ease of use and visualization of results. PMID:15193095

  9. USNRC regulatory guidance for engineered safety feature air cleaning systems

    International Nuclear Information System (INIS)

    The need for clear, technically appropriate, and easily implementable guidance for the design, testing, and maintenance of nuclear air cleaning systems has long been recognized. Numerous industry consensus standards have been issued and revised over the last 30 years. Guidance has also been published by the US Nuclear Regulatory Commission in the form of regulations, regulatory guides, standard review plans, NUREG documents, and information notices. This paper will summarize the latest revisions to these documents and emphasize Regulatory Guide 1.52, Design, Testing, and Maintenance Criteria for Post-Accident Engineered-Safety-Feature Atmosphere Cleanup System Air Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power Plants, which was last revised in 1978. The USNRC has undertaken a project to revise this regulatory guide, and the status of that revision is highlighted

  10. Application of Computer Model to Estimate the Consistency of Air Conditioning Systems Engineering

    OpenAIRE

    Amal El-Berry; Afrah Al-Bossly

    2013-01-01

    Reliability engineering is utilized to predict the performance and optimization of the design and maintenance of air conditioning systems. There are a number of failures associated with the conditioning systems. The failures of an air conditioner such as turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply and loss of air flow entirely are mainly due to a variety of problems with one or more components of an air conditioner o...

  11. Coolant recirculation device for reactors

    International Nuclear Information System (INIS)

    Purpose: To surely remove gases in coolants by the provision of a gas separator having a coolant stay chamber in the midway of coolant flow circuit. Constitution: In an LMFBR type reactor, a gas separator for taking out incompressible gases contained in coolants is provided in the midway of coolant flow circuit comprising a coolant flowing pipeway connected to a reactor, a heat exchange and a coolant recycling pump. The gas separator comprises a vessel-shaped coolant stay chamber, inlet and exit ports of coolants opened to the stay chamber, and a take out port for taking out gases separated from the coolants in the stay chamber. Since the incompressible gases in the coolants have lower density than the coolants, they are collected in the upper cover gas plenum and can surely be eliminated to thereby prevent the gases from flowing into the reactor. (Kawakami, Y.)

  12. Exergy Analysis of the Revolving Vane Compressed Air Engine

    Directory of Open Access Journals (Sweden)

    Alison Subiantoro

    2016-01-01

    Full Text Available Exergy analysis was applied to a revolving vane compressed air engine. The engine had a swept volume of 30 cm3. At the benchmark conditions, the suction pressure was 8 bar, the discharge pressure was 1 bar, and the operating speed was 3,000 rev·min−1. It was found that the engine had a second-law efficiency of 29.6% at the benchmark conditions. The contributors of exergy loss were friction (49%, throttling (38%, heat transfer (12%, and fluid mixing (1%. A parametric study was also conducted. The parameters to be examined were suction reservoir pressure (4 to 12 bar, operating speed (2,400 to 3,600 rev·min−1, and rotational cylinder inertia (0.94 to 2.81 g·mm2. The study found that a higher suction reservoir pressure initially increased the second-law efficiency but then plateaued at about 30%. With a higher operating speed and a higher cylinder inertia, second-law efficiency decreased. As compared to suction pressure and operating speed, cylinder inertia is the most practical and significant to be modified.

  13. Air fuel ratio detector corrector for combustion engines using adaptive neurofuzzy networks

    OpenAIRE

    Nidhi Arora; Swati Mehta

    2013-01-01

    A perfect mix of the air and fuel in internal combustion engines is desirable for proper combustion of fuel with air. The vehicles running on road emit harmful gases due to improper combustion. This problem is severe in heavy vehicles like locomotive engines. To overcome this problem, generally an operator opens or closes the valve of fuel injection pump of locomotive engines to control amount of air going inside the combustion chamber, which requires constant monitoring. A model is proposed ...

  14. DESIGN OF SECONDARY AIR SYSTEM AND THERMAL MODELS FOR TRIPLE SPOOL JET ENGINES

    OpenAIRE

    Caty, Fabien

    2012-01-01

    This master thesis deals with the understanding of the secondary air system of athree spool turbofan. The main purpose is the creation of secondary air systemand thermal models to evaluate the behavior of this kind of engine architectureand estimate the pros and cons in comparison with a typical two spool turbofan. Afinite element model of the secondary air system of the engine has been designedbased on the experience of typical jet engines manufactured by Snecma. Theinner thermodynamic patte...

  15. AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT II, MAINTAINING THE AIR SYSTEM--DETROIT DIESEL ENGINES.

    Science.gov (United States)

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE AIR SYSTEM. TOPICS ARE (1) OPERATION AND FUNCTION, (2) AIR CLEANER, (3) AIR SHUT-DOWN HOUSING, (4) EXHAUST SYSTEM, (5) BLOWER, (6) TURBOCHARGER, AND (7) TROUBLE-SHOOTING TIPS ON THE AIR SYSTEM. THE MODULE CONSISTS OF A…

  16. Chemistry of sodium coolant

    International Nuclear Information System (INIS)

    Properties of impurities of nuclear fuel and its fission products and their behaviour in sodium coolant of the primary circuit of fast reactors are considered. The impurities are classified with account of their properties, behaviour in the circuit and significance

  17. Organic coolant summary report

    International Nuclear Information System (INIS)

    This report summarizes the development of the use of organic liquids, specifically the terphenyls, as heat transfer mediums in nuclear reactors. All phases of the development program are covered, including the choice of coolant, decomposition, coolant reprocessing, physical properties, fouling, heat transfer, and corrosion. Few experimental results are given, but rather the emphasis is on summarizing the state of the art as it exists within AECL at the end of 1973. (Author)

  18. Impact of Oxygen Enriched Air Intake on the Exhaust of a Single Cylinder Diesel Engine

    OpenAIRE

    Rajkumar, K; Govindarajan, P

    2011-01-01

    Problem statement: The objective of the research is to investigate the effect of using oxygen enriched air on Diesel engine exhaust emission. Approach: In the present experimental work a computerized Single cylinder Diesel engine with data acquisition system was used to study the effects of oxygen enriched air intake on Exhaust emissions. Engine test has been carried out in the above said engine for different loads and Exhaust Emissions like CO, CO2, NOx and HC with respec...

  19. LOFT LOCE transient thermal analysis for 6 in., 8 in., 10 in., and 12 in. primary coolant blowdown piping. Research, engineering, and construction report

    International Nuclear Information System (INIS)

    Several sections of the LOFT primary coolant blowdown piping were analyzed for temperature transients occurring during a Loss of Coolant Experiment (LOCE). The LOCE fluid conditions were chosen to conservatively represent the most severe operating conditions occurring in the piping. Temperature gradients will be used by the Applied Mechanics Branch to determine thermal stresses and the allowable thermal cycles for the piping. The only other significant thermal cycle (heat-up or cooldown) was not analyzed because the DTs for this cycle for the pipe sections analyzed will be small (less than 150F) and will have a very minor effect on the allowable number of thermal cycles. 8 inch-Sch 160, 10 inch-Sch 140, 12 inch-Sch 160, and a special 6 inch section of stainless steel piping were analyzed. The temperature gradients for each case were expressed in the DT form required for the ASME Section III pipe equations

  20. Fuel-coolant interactions

    International Nuclear Information System (INIS)

    An important aspect of nuclear fuel behaviour that impacts on the fuel cycle is the interaction of the cladding with the coolant. In particular, the accumulation of deposited crud (corrosion products transported in the reactor coolant) on fuel element surfaces can severely hamper fuel performance by impeding heat transfer and promoting cladding corrosion, both of which may lead to fuel defects and the release of fission products and actinides to the primary coolant systems. Crud deposition is therefore an important consideration in reactor operation; it not only leads to poor performance and radiation field growth by exacerbating fuel defects but also serves as the source of radionuclides such as Co-60 which are major contaminants of out-reactor components. Furthermore, the sequestering of boron from the coolant by fuel deposits in PWRs can give rise to control problems as reactor flux characteristics are modified. As utilities apply the ALARA principle (As Low As Reasonably) to the management of occupational radiation doses and at the same time endeavour to optimise the fuel cycle, it becomes clear that an understanding of the mechanisms involved in coolant-cladding interactions is vital. There are several mechanisms of interest here. The source of crud is the fundamental corrosion process accruing on surfaces of the coolant system and the interaction of that process with local regimes of coolant flow. Accordingly, differences in the chemical and physical condition of the coolant across the reactor core and the steam generators are important factors in CANDUs and PWRs determining release of corrosion products from surfaces, while similar processes along the feedtrain influence crud levels in the reactor coolant in BWRs. The nature of suspended crud, which is determined by the materials of construction of the various components of the coolant system and the chemistry control of the coolant itself, determines the interaction with fuel cladding. Thus, crud in CANDUs

  1. A combined air cycle used for IC engine supercharging based on waste heat recovery

    International Nuclear Information System (INIS)

    Highlights: • A combined air cycle is proposed for IC engine supercharging based on WHR. • Cycle efficiency and energy recovery efficiency depend largely on working pressure. • Exhaust gas pressure of IC engine with combined air cycle is reduced largely. • IC engine fuel efficiency can be increased by 4.1% points at most. - Abstract: A combined air cycle is designed for internal combustion (IC) engine supercharging, which consists of IC engine working cycle and bottom cycle of waste heat recovery (WHR). The bottom cycle uses IC engine exhaust gas as cycle heat source, and its output power is used to drive the gas compressor. Both the heat transfer and thermodynamic processes of combined air cycle were investigated by numerical calculation under various cycle parameters and IC engine operating conditions. On this basis, the performances of combined air cycle and the improvement to IC engine performances were analyzed. Results show that, the cycle efficiency and exhaust gas energy recovery efficiency depend largely on the working pressure, and their maximum values appear at the working pressure of 0.35 MPa and 0.2 MPa, respectively. Compared with the naturally aspirated (NA) engine and turbocharging engine, this approach can make the fuel utilization efficiency of IC engine increase by 8.9% points and 4.1% points at most, respectively, due to the reduction of exhaust gas pressure. All these demonstrate that the proposed concept is a potentially useful approach for IC engine energy saving

  2. ENVIRONMENTALLY REDUCING OF COOLANTS IN METAL CUTTING

    Directory of Open Access Journals (Sweden)

    Veijo KAUPPINEN

    2012-11-01

    Full Text Available Strained environment is a global problem. In metal industries the use of coolant has become more problematic in terms of both employee health and environmental pollution. It is said that the use of coolant forms approximately 8 - 16 % of the total production costs.The traditional methods that use coolants are now obviously becoming obsolete. Hence, it is clear that using a dry cutting system has great implications for resource preservation and waste reduction. For this purpose, a new cooling system is designed for dry cutting. This paper presents the new eco-friendly cooling innovation and the benefits gained by using this method. The new cooling system relies on a unit for ionising ejected air. In order to compare the performance of using this system, cutting experiments were carried out. A series of tests were performed on a horizontal turning machine and on a horizontal machining centre.

  3. Engineering professor wins $100,000 Air Force Young Investigator Award

    OpenAIRE

    Mackay, Steven D.

    2008-01-01

    The U.S. Air Force Office of Scientific Research has awarded Shashank Priya, associate professor of mechanical engineering in the College of Engineering at Virginia Tech, a $100,000, three-year renewable grant to conduct basic research in the area of high-frequency electronic components, titled Domain Engineered Magnetoelectric Thin Films for High Sensitivity Resonant Magnetic Field Sensors.

  4. INVESTIGATION OF CLEANER TECHNOLOGIES TO MINIMIZE AUTOMOTIVE COOLANT WASTES

    Science.gov (United States)

    The US Environmental Protection Agency in cooperation with the State of New Jersey evaluated chemical filtration and distillation technologies designed to recycle automotive and heavy-duty engine coolants. These evaluations addressed the product quality, waste reduction and econo...

  5. Reactor coolant cleanup facility

    International Nuclear Information System (INIS)

    A depressurization device is disposed in pipelines upstream of recycling pumps of a reactor coolant cleanup facility to reduce a pressure between the pressurization device and the recycling pump at the downstream, thereby enabling high pressure coolant injection from other systems by way of the recycling pumps. Upon emergency, the recycling pumps of the coolant cleanup facility can be used in common to an emergency reactor core cooling facility and a reactor shutdown facility. Since existent pumps of the emergency reactor core cooling facility and the reactor shutdown facility which are usually in a stand-by state can be removed, operation confirmation test and maintenance for equipments in both of facilities can be saved, so that maintenance and reliability of the plant are improved and burdens on operators can also be mitigated. Moreover, low pressure design can be adopted for a non-regenerative heat exchanger and recycling coolant pumps, which enables to improve the reliability and economical property due to reduction of possibility of leakage. (N.H.)

  6. Environmentally Friendly Coolant System

    Energy Technology Data Exchange (ETDEWEB)

    David Jackson Principal Investigator

    2011-11-08

    Energy reduction through the use of the EFCS is most improved by increasing machining productivity. Throughout testing, nearly all machining operations demonstrated less land wear on the tooling when using the EFCS which results in increased tool life. These increases in tool life advance into increased productivity. Increasing productivity reduces cycle times and therefore reduces energy consumption. The average energy savings by using the EFCS in these machining operations with these materials is 9%. The advantage for end milling stays with flood coolant by about 6.6% due to its use of a low pressure pump. Face milling and drilling are both about 17.5% less energy consumption with the EFCS than flood coolant. One additional result of using the EFCS is improved surface finish. Certain machining operations using the EFCS result in a smoother surface finish. Applications where finishing operations are required will be able to take advantage of the improved finish by reducing the time or possibly eliminating completely one or more finishing steps and thereby reduce their energy consumption. Some machining operations on specific materials do not show advantages for the EFCS when compared to flood coolants. More information about these processes will be presented later in the report. A key point to remember though, is that even with equivalent results, the EFCS is replacing petroleum based coolants whose production produces GHG emissions and create unsafe work environments.

  7. Promena fizičko-hemijskih karakteristika sredstava za hlađenje motora tokom eksploatacije vozila / Change in physic-chemical characteristics of engine coolants during vehicle exploitation

    Directory of Open Access Journals (Sweden)

    Sreten R. Perić

    2008-07-01

    Full Text Available Identifikacija stanja sistema hlađenja bez narušavanja njegove funkcije, u uslovima kada do otkaza dolazi, pre svega, usled promene fizičko-hemijskih svojstava rashladnog sredstva motora, ima velike tehničke i ekonomske efekte. Kako se promena funkcionalnosti složenog sistema hlađenja najčešće ogleda u promenama karakteristika sredstva za hlađenje, promena fizičko-hemijskih karakteristika sredstva za hlađenje može se usvojiti kao parametar za ocenu stanja sistema hlađenja. Za ocenu i analizu fizičko-hemijskih karakteristika sredstva za hlađenje danas postoji veoma razvijena merna oprema. / Identification of the condition of a cooling system without disturbing its function, when failures primarily occur due to changes in physic- chemical characteristics of engine cooling agents, has considerable technical and economical effects. Since change in functionality of complex cooling systems is most often a consequence of changes in the characteristics of cooling agents, the change of physic-chemical characteristics of coolants can be accepted as a parameter for evaluating cooling system conditions. There is nowadays a wide range of sophisticated measuring equipment for evaluation and analysis of physic-chemical characteristics of coolants.

  8. Comparison Based on Exergetic Analyses of Two Hot Air Engines: A Gamma Type Stirling Engine and an Open Joule Cycle Ericsson Engine

    OpenAIRE

    Houda Hachem; Marie Creyx; Ramla Gheith; Eric Delacourt; Céline Morin; Fethi Aloui; Sassi Ben Nasrallah

    2015-01-01

    In this paper, a comparison of exergetic models between two hot air engines (a Gamma type Stirling prototype having a maximum output mechanical power of 500 W and an Ericsson hot air engine with a maximum power of 300 W) is made. Referring to previous energetic analyses, exergetic models are set up in order to quantify the exergy destruction and efficiencies in each type of engine. The repartition of the exergy fluxes in each part of the two engines are determined and represented in Sankey di...

  9. Research on Coolant Radiochemistry

    International Nuclear Information System (INIS)

    The final objective of this study is to develop a method for reducing radioactive materials formed in the reactor coolant circuit. This second stage research was categorized into the following three subgroups: the development of the estimation technique of microscopic chemical variation at high temperatures and pressures, the fundamental study on the thermodynamics at high temperatures and pressures, and the study on the deposition of metal oxides and the determination of the main factors responsible for the growth of CRUD. First, in the development of the estimation technique of microscopic chemical change at high temperatures and pressures, the technique for measuring coolant chemistry such as pH, conductivity and Eh was developed to be appropriate for the high temperature and pressure condition. The coolant chemistry measuring system including the self-devised high temperature pH sensor can be applied to the field of nuclear reactor and contribute on a large scale in the automation of the coolant chemistry control and the establishment of the real-time on-line measuring technique. Secondly, the dissociation constant of water and the solubility of metal oxides were measured in the fundamental study on the thermodynamics at high temperatures and pressures. Finally, in the study on the deposition of metal oxides and the determination of the main factors responsible for the growth of CRUD, the careful investigation of the deposition phenomena of micro particles on the cladding surface showed that subcooled boiling and the dissolved hydrogen are the main factors responsible for the growth of CRUD. In addition, the basis was provided for the construction of a new particle behavior model in the reactor coolant circuit

  10. Air emissions inventory for the Idaho National Engineering Laboratory -- 1995 emissions report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report presents the 1995 update of the Air Emission Inventory for the Idaho National Engineering Laboratory (INEL). The INEL Air Emission Inventory documents sources and emissions of non-radionuclide pollutants from operations at the INEL. The report describes the emission inventory process and all of the sources at the INEL, and provides non-radionuclide emissions estimates for stationary sources. The air contaminants reported include nitrogen oxides, sulfur oxides, carbon monoxide, volatile organic compounds, particulates, and hazardous air pollutants (HAPs).

  11. Air emissions inventory for the Idaho National Engineering Laboratory -- 1995 emissions report

    International Nuclear Information System (INIS)

    This report presents the 1995 update of the Air Emission Inventory for the Idaho National Engineering Laboratory (INEL). The INEL Air Emission Inventory documents sources and emissions of non-radionuclide pollutants from operations at the INEL. The report describes the emission inventory process and all of the sources at the INEL, and provides non-radionuclide emissions estimates for stationary sources. The air contaminants reported include nitrogen oxides, sulfur oxides, carbon monoxide, volatile organic compounds, particulates, and hazardous air pollutants (HAPs)

  12. Optimization Study on a Single-cylinder Compressed Air Engine

    Institute of Scientific and Technical Information of China (English)

    YU Qihui; CAI Maolin; SHI Yan; XU Qiyue

    2015-01-01

    The current research of compressed air engine (CAE) mainly focused on simulations and system integrations. However, energy efficiency and output torque of the CAE is limited, which restricts its application and popularization. In this paper, the working principles of CAE are briefly introduced. To set a foundation for the study on the optimization of the CAE, the basic mathematical model of working processes is set up. A pressure-compensated valve which can reduce the inertia force of the valve is proposed. To verify the mathematical model, the prototype with the newly designed pressure-compensated intake valve is built and the experiment is carried out, simulation and experimental results of the CAE are conducted, and pressures inside the cylinder and output torque of the CAE are obtained. Orthogonal design and grey relation analysis are utilized to optimize structural parameters. The experimental and optimized results show that, first of all, pressure inside the cylinder has the same changing tendency in both simulation curve and experimental curve. Secondly, the highest average output torque is obtained at the highest intake pressure and the lowest rotate speed. Thirdly, the optimization of the single-cylinder CAE can improve the working efficiency from an original 21.95% to 50.1%, an overall increase of 28.15%, and the average output torque increases also increases from 22.047 5 N • m to 22.439 N • m. This research designs a single-cylinder CAE with pressure-compensated intake valve, and proposes a structural parameters design method which improves the single-cylinder CAE performance.

  13. Optimization study on a single-cylinder compressed air engine

    Science.gov (United States)

    Yu, Qihui; Cai, Maolin; Shi, Yan; Xu, Qiyue

    2015-11-01

    The current research of compressed air engine (CAE) mainly focused on simulations and system integrations. However, energy efficiency and output torque of the CAE is limited, which restricts its application and popularization. In this paper, the working principles of CAE are briefly introduced. To set a foundation for the study on the optimization of the CAE, the basic mathematical model of working processes is set up. A pressure-compensated valve which can reduce the inertia force of the valve is proposed. To verify the mathematical model, the prototype with the newly designed pressure-compensated intake valve is built and the experiment is carried out, simulation and experimental results of the CAE are conducted, and pressures inside the cylinder and output torque of the CAE are obtained. Orthogonal design and grey relation analysis are utilized to optimize structural parameters. The experimental and optimized results show that, first of all, pressure inside the cylinder has the same changing tendency in both simulation curve and experimental curve. Secondly, the highest average output torque is obtained at the highest intake pressure and the lowest rotate speed. Thirdly, the optimization of the single-cylinder CAE can improve the working efficiency from an original 21.95% to 50.1%, an overall increase of 28.15%, and the average output torque increases also increases from 22.047 5 N • m to 22.439 N • m. This research designs a single-cylinder CAE with pressure-compensated intake valve, and proposes a structural parameters design method which improves the single-cylinder CAE performance.

  14. Development of Figure of Merits (FOMs) for Intermediate Coolant Characterization and Selection

    International Nuclear Information System (INIS)

    This paper focuses on characterization of several coolant performances in the IHTL. There are lots of choices available for the IHTL coolants; gases, liquid metals, molten salts, and etc. Traditionally, the selection of coolants is highly dependent on engineer's experience and decisions. In this decision, the following parameters are generally considered: melting point, vapor pressure, density, thermal conductivity, heat capacity, viscosity, and coolant chemistry. The followings are general thermal-hydraulic requirements for the coolant in the IHTL: (1) High heat transfer performance - The IHTL coolant should exhibit high heat transfer performance to achieve high efficiency and economics; (2) Low pumping power - The IHTL coolant requires low pumping power to improve economics through less stringent pump requirements; (3) Low amount of coolant volume - The IHTL coolant requires less coolant volume for better economics; (4) Low amount of structural materials - The IHTL coolant requires less structural material volume for better economics; (5) Low heat loss - The IHTL requires less heat loss for high efficiency; and (6) Low temperature drop - The IHTL should allow less temperature drop for high efficiency. Typically, heat transfer coolants are selected based on various fluid properties such as melting point, vapor pressure, density, thermal conductivity, heat capacity, viscosity, and coolant chemistry. However, the selection process and results are highly dependent on the engineer's personal experience and skills. In the coolant selection, if a certain coolant shows superior properties with respect to the others, the decision will be very straightforward. However, generally, each coolant material exhibits good characteristics for some properties but poor for the others. Therefore, it will be very useful to have some figures of merits (FOMs), which can represent and quantify various coolant thermal performances in the system of interest. The study summarized in this

  15. PERFORMANCE CALCULATION OF A SPARK IGNITON ENGINE ACCORDING TO THE IDEAL AIR-FUEL CYCLE ANALYSIS

    OpenAIRE

    Perihan ERDURANLI; KOCA, Atilla; Yakup SEKMEN

    2010-01-01

    ABSTRACTDepending on the development in computer technologies by using theoretical models in the design of internal combustion engines, the effects of different operating and design parameters on engine performance and performance characteristics of a real engine can be estimated with shorter time and lower cost. In this study, a mathematical simulation model is developed to investigate ideal air-fuel cycle analysis of a single cylinder, four-stroke and natural aspirated spark ignition engine...

  16. Investigations of Air-Cooled Turbine Rotors for Turbojet Engines. 1: Experimental Disk Temperature Distribution in Modified J33 Split-Disk Rotor at Speeds up to 6000 RPM

    Science.gov (United States)

    Schramm, Wilson B.; Ziemer, Robert R.

    1952-01-01

    An experimental investigation is being conducted at the Lewis laboratory to establish general principles for the design of noncritical turbine rotor configurations. This investigation includes evaluation of cooling effectiveness, structural stability, cooling-air flow distribution characteristics, and methods of supplying cooling air to the turbine rotor blades. Prior to design of a noncritical rotor, a standard turbine rotor of a commerical turbojet engine was split in the plane of rotation and machined to provide a passage for distributing cooling air to the base of each blade. The rotor was fitted with nontwisted, hollow, aircooled blades containing nine tubes in the coolant passage. In the investigation reported herein, the modified turbine rotor operated successfully up to speeds of 6000 rpm with ratios of cooling-air to combustion-gas flow as low as 0.02. The disk temperatures observed at these conditions were below 450 0 F when cooling air at 100 F was used from the laboratory air system. The calculated disk temperatures based on the correlation method presented for rated engine conditions were well below 1000 F at a cooling-air flow ratio of 0.02, which is considered adequate for a noncritical rotor. An appreciable difference in temperature level existed between the forward and rear disks. This temperature difference probably introduced undesirable disk stress distributions as a result of the relative elongations of the two disks. This investigation was terminated at 6000 rpm so that slight changes in the engine configuration could be made to relieve this condition.

  17. Transient Air-Fuel Ratio Control in a CNG Engine Using Fuzzy Neural Networks

    Institute of Scientific and Technical Information of China (English)

    LI Guo-xiu; ZHANG Xin

    2005-01-01

    The fuzzy neural networks has been used as means of precisely controlling the air-fuel ratio of a lean-burn compressed natural gas (CNG) engine. A control algorithm, without based on engine model, has been utilized to construct a feedforward/feedback control scheme to regulate the air-fuel ratio. Using fuzzy neural networks, a fuzzy neural hybrid controller is obtained based on PI controller. The new controller, which can adjust parameters online, has been tested in transient air-fuel ratio control of a CNG engine.

  18. An experimental setup for the study of the steady air flow in a diesel engine chamber

    OpenAIRE

    Montanero José María; Marcos Alberto; Castilla Alejandro; Vega Emilio José; Fernández Joaquín; Barrio Raúl

    2012-01-01

    We present an experimental setup for studying the steady air flow in a diesel engine chamber. An engine block containing the inlet manifold was placed on a test bench. A steady air stream crossed the inlet manifold and entered a glass chamber driven by a fan. A PIV system was set up around the bench to measure the in-chamber flow. An air spray gun was used as seed generator to producing sub-millimeter droplets, easily dragged by the air stream. Images of the in-flow chamber were acquired in t...

  19. Intelligent energy management control of vehicle air conditioning system coupled with engine

    International Nuclear Information System (INIS)

    Vehicle Air Conditioning (AC) systems consist of an engine powered compressor activated by an electrical clutch. The AC system imposes an extra load to the vehicle's engine increasing the vehicle fuel consumption and emissions. Energy management control of the vehicle air conditioning is a nonlinear dynamic system, influenced by uncertain disturbances. In addition, the vehicle energy management control system interacts with different complex systems, such as engine, air conditioning system, environment, and driver, to deliver fuel consumption improvements. In this paper, we describe the energy management control of vehicle AC system coupled with vehicle engine through an intelligent control design. The Intelligent Energy Management Control (IEMC) system presented in this paper includes an intelligent algorithm which uses five exterior units and three integrated fuzzy controllers to produce desirable internal temperature and air quality, improved fuel consumption, low emission, and smooth driving. The three fuzzy controllers include: (i) a fuzzy cruise controller to adapt vehicle cruise speed via prediction of the road ahead using a Look-Ahead system, (ii) a fuzzy air conditioning controller to produce desirable temperature and air quality inside vehicle cabin room via a road information system, and (iii) a fuzzy engine controller to generate the required engine torque to move the vehicle smoothly on the road. We optimised the integrated operation of the air conditioning and the engine under various driving patterns and performed three simulations. Results show that the proposed IEMC system developed based on Fuzzy Air Conditioning Controller with Look-Ahead (FAC-LA) method is a more efficient controller for vehicle air conditioning system than the previously developed Coordinated Energy Management Systems (CEMS). - Highlights: ► AC interacts: vehicle, environment, driver components, and the interrelationships between them. ► Intelligent AC algorithm which uses

  20. A Study of Performance Output of a Multivane Air Engine Applying Optimal Injection and Vane Angles

    Directory of Open Access Journals (Sweden)

    Bharat Raj Singh

    2012-01-01

    Full Text Available This paper presents a new concept of the air engine using compressed air as the potential power source for motorbikes, in place of an internal combustion engine. The motorbike is proposed to be equipped with an air engine, which transforms the energy of the compressed air into mechanical motion energy. A mathematical model is presented here, and performance evaluation is carried out on an air-powered novel air turbine engine. The maximum power output is obtained as 3.977 kW (5.50 HP at the different rotor to casing diameter ratios, optimal injection angle 60°, vane angle 45° for linear expansion (i.e., at minimum air consumption when the casing diameter is kept 100 mm, at injection pressure 6 bar (90 psi and speed of rotation 2500 rpm. A prototype air engine is built and tested in the laboratory. The experimental results are also seen much closer to the analytical values, and the performance efficiencies are recorded around 70% to 95% at the speed of rotation 2500–3000 rpm.

  1. Air/fuel supply system for use in a gas turbine engine

    Science.gov (United States)

    Fox, Timothy A; Schilp, Reinhard; Gambacorta, Domenico

    2014-06-17

    A fuel injector for use in a gas turbine engine combustor assembly. The fuel injector includes a main body and a fuel supply structure. The main body has an inlet end and an outlet end and defines a longitudinal axis extending between the outlet and inlet ends. The main body comprises a plurality of air/fuel passages extending therethrough, each air/fuel passage including an inlet that receives air from a source of air and an outlet. The fuel supply structure communicates with and supplies fuel to the air/fuel passages for providing an air/fuel mixture within each air/fuel passage. The air/fuel mixtures exit the main body through respective air/fuel passage outlets.

  2. Analysis and simulation of mobile air conditioning system coupled with engine cooling system

    International Nuclear Information System (INIS)

    Many components of the mobile air conditioning system and engine cooling system are closely interrelated and make up the vehicle climate control system. In the present paper, a vehicle climate control system model including air conditioning system and engine cooling system has been proposed under different operational conditions. All the components have been modeled on the basis of experimental data. Based on the commercial software, a computer simulation procedure of the vehicle climate control system has been developed. The performance of the vehicle climate control system is simulated, and the calculational data have good agreement with experimental data. Furthermore, the vehicle climate control simulation results have been compared with an individual air conditioning system and engine cooling system. The influences between the mobile air conditioning system and the engine cooling system are discussed

  3. Air Force funded researcher engineers enzymes to advance the hydrogen economy

    OpenAIRE

    Trulove, Susan

    2007-01-01

    Y. H. Percival Zhang, assistant professor of biological systems engineering at Virginia Tech, has received an Air Force Young Investigator award to advance development of an onboard process to convert a cellulosic material into hydrogen to power fuel cell vehicles.

  4. Impact of Oxygen Enriched Air Intake on the Exhaust of a Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    K. Rajkumar

    2011-01-01

    Full Text Available Problem statement: The objective of the research is to investigate the effect of using oxygen enriched air on Diesel engine exhaust emission. Approach: In the present experimental work a computerized Single cylinder Diesel engine with data acquisition system was used to study the effects of oxygen enriched air intake on Exhaust emissions. Engine test has been carried out in the above said engine for different loads and Exhaust Emissions like CO, CO2, NOx and HC with respect to different percentage of oxygen enrichment were discussed. Results and Conclusion: Increasing the oxygen content with the air leads to faster burn rates and the ability to control Exhaust Emissions. Added oxygen in the combustion air offers more potential for burning diesel. Oxy-fuel combustion reduces the volume of flue gases and reduces the effects of green house effect also.

  5. Development of an Engine Air-Brake for Quiet Drag Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel quiet engine air-brake (EAB) is proposed in response to NASA's solicitation for active and passive noise control concepts for conventional and advanced...

  6. Development of an Engine Air-Brake for Quiet Drag Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel quiet engine air-brake is proposed in response to NASA's solicitation for concepts for active and passive control of noise sources for conventional and...

  7. Cascade exchange pressure supercharging system of the transport engine with deep cooling of intake air

    OpenAIRE

    Alekseev, S; Krajniuk, A.

    2010-01-01

    The new principle of the organisation of working process of the combined supercharging system of Internal Comdustion Engine (ICE) with the Cascade Pressure Exchanger(CPE) has been described. It allows considerably to raise level of forcing of the engine by supercharging at the expense of expansion of effective air supply area and coolings of supercharging air to temperature below an ambient without attraction of additional mechanical energy on refrigeration cycle realization. Substantiv...

  8. Development Study of Mach 6 Turbojet Engine with Air-Precooling

    Science.gov (United States)

    Sato, T.; Taguchi, H.; Kobayashi, H.; Kojima, T.

    This paper discusses the current R&D status and plans concerning a Mach 6 turbojet engine with an air-precooling system for the first stage of a two-stage-to-orbit space plane (TSTO). An air-turbo ramjet engine with the expander-cycle (ATREX) has been designed and tested at sea level static conditions, which demonstrated the engine system and component performance. Experimental and numerical research of the components have also been conducted to build the fundamental technologies and to improve the engine performance. Some innovative ideas were proposed such as a multi-row-disk inlet and a defrosting method on precooler tubes using methanol. As the next step, the development of a subscale flight-type engine (S-engine) has started. The partial expander cycle was selected instead of the full expander cycle as the prototype engine cycle as a result of optimizing analyses. Total length and weight of S-engine are about 2.2 m and 100 kg respectively including a variable air-inlet and nozzle. Because S-engine will be tested in a flight demonstration program after ground tests, it must be designed with consideration of weight reduction as well as keeping of the high performance. The first engine flight test will be around Mach 2, using a balloon dropped test vehicle. This is scheduled in 2007 FY.

  9. Comparison Based on Exergetic Analyses of Two Hot Air Engines: A Gamma Type Stirling Engine and an Open Joule Cycle Ericsson Engine

    Directory of Open Access Journals (Sweden)

    Houda Hachem

    2015-10-01

    Full Text Available In this paper, a comparison of exergetic models between two hot air engines (a Gamma type Stirling prototype having a maximum output mechanical power of 500 W and an Ericsson hot air engine with a maximum power of 300 W is made. Referring to previous energetic analyses, exergetic models are set up in order to quantify the exergy destruction and efficiencies in each type of engine. The repartition of the exergy fluxes in each part of the two engines are determined and represented in Sankey diagrams, using dimensionless exergy fluxes. The results show a similar proportion in both engines of destroyed exergy compared to the exergy flux from the hot source. The compression cylinders generate the highest exergy destruction, whereas the expansion cylinders generate the lowest one. The regenerator of the Stirling engine increases the exergy resource at the inlet of the expansion cylinder, which might be also set up in the Ericsson engine, using a preheater between the exhaust air and the compressed air transferred to the hot heat exchanger.

  10. Experimental Investigation on the Performance of a Compressed-Air Driven Piston Engine

    Directory of Open Access Journals (Sweden)

    Chih-Jie Yu

    2013-03-01

    Full Text Available This study presents an experimental investigation of a piston engine driven by compressed air. The compressed air engine was a modified 100 cm3 internal combustion engine obtained from a motorcycle manufacturer. The experiments in this study used a test bench to examine the power performance and pressure/temperature variations of the compressed air engine at pressures ranging from 5 to 9 bar (absolute pressure. The engine was modified from a 4-stroke to a 2-stroke engine using a cam system driven by a crankshaft and the intake and exhaust valves have a small lift due to this modification. The highest power output of 0.95 kW was obtained at 9 bar and 1320 rpm. The highest torque of 9.99 N·m occurred at the same pressure, but at 465 rpm. The pressure-volume (P-V diagram shows that cylinder pressure gradually increases after the intake valve opens because of the limited lift movement of the intake valve. Similar situations occurred during the exhaust process, restricting the power output of the compressed air engine. The pressure and temperature variation of the air at engine inlet and outlet were recorded during the experiment. The outlet pressure increased from 1.5 bar at 500 rpm to 2.25 bar at 2000 rpm, showing the potential of recycling the compressed air energy by attaching additional cylinders (split-cycle engine. A temperature decrease (from room temperature to 17 °C inside the cylinder was observed. It should be noted that pressures higher than that currently employed can result in lower temperatures and this can cause poor lubrication and sealing issues. The current design of a compressed air engine, which uses a conventional cam mechanism for intake and exhaust, has limited lift movement during operation, and has a restricted flow rate and power output. Fast valve actuation and a large lift are essential for improving the performance of the current compressed air engine. This study presents a power output examination with the pressure

  11. Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory - Calendar Year 1999 Emission Report

    Energy Technology Data Exchange (ETDEWEB)

    Zohner, S.K.

    2000-05-30

    This report presents the 1999 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradionuclide emissions estimates for stationary sources.

  12. Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory - Calendar Year 1998 Emissions Report

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Zohner

    1999-10-01

    This report presents the 1998 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradiological emissions estimates for stationary sources.

  13. Air emission inventory for the Idaho National Engineering Laboratory: 1994 emissions report

    International Nuclear Information System (INIS)

    This report Presents the 1994 update of the Air Emission inventory for the Idaho National Engineering Laboratory (INEL). The INEL Air Emission Inventory documents sources and emissions of non-radionuclide pollutants from operations at the INEL. The report describes the emission inventory process and all of the sources at the INEL, and provides non-radionuclide emissions estimates for stationary sources

  14. Air Emission Inventory for the Idaho National Engineering Laboratory, 1993 emissions report

    International Nuclear Information System (INIS)

    This report presents the 1993 update of the Air Emission Inventory for the Idaho National Engineering Laboratory (INEL). The purpose of the Air Emission Inventory is to commence the preparation of the permit to operate application for the INEL, as required by the recently promulgated Title V regulations of the Clean Air Act. The report describes the emission inventory process and all of the sources at the INEL and provides emissions estimates for both mobile and stationary sources

  15. Experimental Investigation of Oxygen Enriched air intake on Combustion Parameters of a Single Cylinder Diesel Engine

    OpenAIRE

    Rajkumar, K; Govindarajan, P

    2010-01-01

    In the present experimental work a computerized Single cylinder Diesel engine with data acquisition system was used to study the effects of oxygen enriched air intake on combustion parameters. Increasing the oxygen content with the air leads to faster burn rates and the ability to burn more fuel at the same stoichiometery. Addedoxygen in the combustion air leads to shorter ignition delays and offers more potential for burning diesel. Oxy-fuel combustion reduces the volume of flue gases and re...

  16. Air Emission Inventory for the Idaho National Engineering Laboratory, 1993 emissions report

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This report presents the 1993 update of the Air Emission Inventory for the Idaho National Engineering Laboratory (INEL). The purpose of the Air Emission Inventory is to commence the preparation of the permit to operate application for the INEL, as required by the recently promulgated Title V regulations of the Clean Air Act. The report describes the emission inventory process and all of the sources at the INEL and provides emissions estimates for both mobile and stationary sources.

  17. MONITORING AND MODELLING OF AIR POLLUTION PRODUCED BY AIRCRAFT ENGINE EMISSION INSIDE THE ATHENS INTERNATIONAL AIRPORT

    Directory of Open Access Journals (Sweden)

    Oleksander I. Zaporozhets

    2009-04-01

    Full Text Available  Experimental measuring of air pollution inside the airport, produced by aircraft engine emission during accelaration and take-off on the runway. Measurement data were used for verification of modelling results according to complex model «PolEmiCa». It consists of the following basic components: engine emission inventory calculation; transport of the contaminants by engine jets, dispersion of the contaminants in atmosphere due to wind and atmospheric turbulence.

  18. Mathematical Modeling of a SI Engine Cycle with Actual Air-Fuel Cycle Analyses

    OpenAIRE

    Perihan SEKMEN; Yakup SEKMEN

    2007-01-01

    The performance of an engine whose basic design parameters are known can be predicted with the assistance of simulation programs into the less time, cost  and near value of actual. However, inadequate areas of the current model can guide future research because the effects of design variables on engine performance can be determined before. In this study, thermodynamic cycle and performance analyses were simulated for various engine speeds (1800, 2400 ve 3600 1/min) and various excess air coef...

  19. Steam as turbine blade coolant: Experimental data generation

    Energy Technology Data Exchange (ETDEWEB)

    Wilmsen, B.; Engeda, A.; Lloyd, J.R. [Michigan State Univ., East Lansing, MI (United States)

    1995-10-01

    Steam as a coolant is a possible option to cool blades in high temperature gas turbines. However, to quantify steam as a coolant, there exists practically no experimental data. This work deals with an attempt to generate such data and with the design of an experimental setup used for the purpose. Initially, in order to guide the direction of experiments, a preliminary theoretical and empirical prediction of the expected experimental data is performed and is presented here. This initial analysis also compares the coolant properties of steam and air.

  20. Alternative Observers for SI Engine Air/Fuel Ratio Control

    DEFF Research Database (Denmark)

    Hendricks, Elbert; Poulsen, Jannik; Olsen, Mads Bruun; Jensen, Per Buchbjerg; Føns, Michael; Jepsen, Christian

    In earlier work it has been shown that a nonlinear observer based on the use of the manifold pressure state equation and a nonlinear fuel film compensator can maintain accurate A/F ratio control during both steady state and transient operation. This observer may be called a manifold absolute pres...... engine control system designer with a variety of robust control systems which can easily be made redundant in order to satisfy newer engine emissions and diagnosis requirements and legislation...

  1. Reactor coolant pump flywheel

    Science.gov (United States)

    Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

    2013-11-26

    A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

  2. Air mass flow estimation in turbocharged diesel engines from in-cylinder pressure measurement

    Energy Technology Data Exchange (ETDEWEB)

    Desantes, J.M.; Galindo, J.; Guardiola, C.; Dolz, V. [CMT - Motores Termicos, Universidad Politecnica de Valencia (Spain)

    2010-01-15

    Air mass flow determination is needed for the control of current internal combustion engines. Current methods are based on specific sensors (as hot wire anemometers) or indirect estimation through manifold pressure. With the availability of cylinder pressure sensors for engine control, methods based on them can be used for replacing or complementing standard methods. Present paper uses in cylinder pressure increase during the intake stroke for inferring the trapped air mass. The method is validated on two different turbocharged diesel engines and compared with the standard methods. (author)

  3. Coolant technology of water cooled reactors. V. 1: Chemistry of primary coolant in water cooled reactors

    International Nuclear Information System (INIS)

    This report is a summary of the work performed within the framework of the Coordinated Research Programme on Investigations on Water Chemistry Control and Coolant Interaction with Fuel and Primary Circuit Materials in Water Cooled Power Reactors organized by the IAEA and carried out from 1987 to 1991. It is the continuation of a programme entitled Reactor Water Chemistry Relevant to Coolant-Cladding Interaction (IAEA-TECDOC-429), which ran from 1981 to 1986. Subsequent meetings resulted in the title of the programme being changed to Coolant Technology of Water Cooled Reactors. The results of this Coordinated Research Programme are published in four volumes with an overview in the Technical Reports Series. The titles of the volumes are: Volume 1: Chemistry of Primary Coolant in Water Cooled Reactors; Volume 2: Corrosion in the Primary Coolant Systems of Water Cooled Reactors; Volume 3: Activity Transport Mechanisms in Water Cooled Reactors; Volume 4: Decontamination of Water Cooled Reactors. These publications should be of interest to experts in water chemistry at nuclear power plants, experts in engineering, fuel designers, research and development institutes active in the field and to consultants to these organizations. Refs, figs and tabs

  4. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    OpenAIRE

    Nureddin Dinler; Nuri Yucel

    2010-01-01

    Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion...

  5. Design and dynamic characteristic prediction of air-powered twin-rotor piston engine

    Institute of Scientific and Technical Information of China (English)

    徐海军; 张雷; 潘存云; 张湘

    2015-01-01

    A novel air-powered twin-rotor piston engine (ATPE) utilizing a differential velocity driving mechanism to achieve a high output torque was proposed. The ATPE had eight separated rotary cylinders which can dynamically enlarge the engine displacement as a result of the special driving mechanism, which was named dynamic volume expansion. The mathematical model of ATPE comprising a dynamic model and a thermodynamic model was established under the assumption of no mechanical friction. The model was numerically simulated in Matlab. The results show that shortage of low output torque confusing traditional air-powered engines can be overcome. The average output torque sharply increases to 100 N·m, which is about three times that of traditional air-powered engines with equal cylinder displacement under the pressure of 0.6 MPa at 480 r/min. ATPE can be used to drive vehicles directly without transmission box, therefore the energy transfer efficiency of ATPE can be increased. Furthermore, benefitting from the novel gas distribution system, the engine shows an ability in self-adjusting under different loads. The arrangements of air ports automatically adjust the open interval of air ports according to the load, which may simplify the speed control system.

  6. Issues of lead coolant technology

    International Nuclear Information System (INIS)

    Starting from 1989 with the BREST-OD-300 reactor design development, some experimental studies related to lead coolant have been performed to provide feasibility of using liquid lead as a coolant in the closed circuit. Further comprehensive analytical and experimental studies are required to develop lead coolant technology for the BREST-OD-300 reactor design. General work program for justification of lead coolant technology are planned aiming at not only getting the information on the components required for the technology realization and their design features but also revealing the possibility of use of data obtained in the course of lead-bismuth circuit operation for the lead circuits. The main results performed so far for justification of BREST-OD-300 reactor coolant technology are presented in this paper. The results confirmed the possibility of using the experience gained on lead-bismuth coolant justification on the stage of the BREST-OD-300 reactor design development. In addition, the results provided directions for further justification of lead coolant technology based on experience gained on lead-bismuth coolant. (author)

  7. Air Emission Inventory for the Idaho National Engineering Laboratory: 1992 emissions report

    Energy Technology Data Exchange (ETDEWEB)

    Stirrup, T.S.

    1993-06-01

    This report presents the 1992 Air Emission Inventory for the Idaho National Engineering Laboratory. Originally, this report was in response to the Environmental Oversight and Monitoring Agreement in 1989 between the State of Idaho and the Department of Energy Idaho Field Office, and a request from the Idaho Air Quality Bureau. The current purpose of the Air Emission Inventory is to provide the basis for the preparation of the INEL Permit-to-Operate (PTO) an Air Emission Source Application, as required by the recently promulgated Title V regulations of the Clean Air Act. This report includes emissions calculations from 1989 to 1992. The Air Emission Inventory System, an ORACLE-based database system, maintains the emissions inventory.

  8. Air Emission Inventory for the Idaho National Engineering Laboratory: 1992 emissions report

    International Nuclear Information System (INIS)

    This report presents the 1992 Air Emission Inventory for the Idaho National Engineering Laboratory. Originally, this report was in response to the Environmental Oversight and Monitoring Agreement in 1989 between the State of Idaho and the Department of Energy Idaho Field Office, and a request from the Idaho Air Quality Bureau. The current purpose of the Air Emission Inventory is to provide the basis for the preparation of the INEL Permit-to-Operate (PTO) an Air Emission Source Application, as required by the recently promulgated Title V regulations of the Clean Air Act. This report includes emissions calculations from 1989 to 1992. The Air Emission Inventory System, an ORACLE-based database system, maintains the emissions inventory

  9. Experimental Investigation of Oxygen Enriched air intake on Combustion Parameters of a Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    K.RAJKUMAR

    2010-08-01

    Full Text Available In the present experimental work a computerized Single cylinder Diesel engine with data acquisition system was used to study the effects of oxygen enriched air intake on combustion parameters. Increasing the oxygen content with the air leads to faster burn rates and the ability to burn more fuel at the same stoichiometery. Addedoxygen in the combustion air leads to shorter ignition delays and offers more potential for burning diesel. Oxy-fuel combustion reduces the volume of flue gases and reduces the effects of green house effect also. Engine test has been carried out in the above said engine for different loads and the following combustion parameters like Ignition delay, Combustion duration, Heat release and Cylinder pressure was discussed.

  10. HEAT EXCHANGE BETWEEN ENGINE BLOCK-CRANKCASE AND AIR FLOWS IN ENGINE COMPARTMENT

    OpenAIRE

    A I Yakubovich; V. E. Tarasenko

    2015-01-01

    A calculation technique is offered to determine convective heat exchange from a block-crankcase of a diesel engine. This technique makes it possible to get more accurate value of a remainder term of heat balance. The convective heat exchange of D-243 diesel engine block-crankcase has been calculated. The heat release of the diesel engine block-crankcase has been analyzed depending on heat field parameters under a tractor hood.

  11. Application of Computer Model to Estimate the Consistency of Air Conditioning Systems Engineering

    Directory of Open Access Journals (Sweden)

    Amal El-Berry

    2013-04-01

    Full Text Available Reliability engineering is utilized to predict the performance and optimization of the design and maintenance of air conditioning systems. There are a number of failures associated with the conditioning systems. The failures of an air conditioner such as turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply and loss of air flow entirely are mainly due to a variety of problems with one or more components of an air conditioner or air conditioning system. To maintain the system forecasting for system failure rates are very important. The focus of this paper is the reliability of the air conditioning systems. The most common applied statistical distributions in reliability settings are the standard (2 parameter Weibull and Gamma distributions. Reliability estimations and predictions are used to evaluate, when the estimation of distributionsparameters is done. To estimate good operating condition in a building, the reliability of the air conditioning system that supplies conditioned air to the several companies’ departments is checked. This air conditioning system is divided into two systems, namely the main chilled water system and the ten air handling systems that serves the ten departments. In a chilled-water system the air conditioner cools water down to 40 - 45oF (4 - 7oC. The chilled water is distributed throughout the building in a piping system and connected to air condition cooling units wherever needed. Data analysis has been done with support a computer aided reliability software, with the application of the Weibull and Gamma distributions it is indicated that the reliability for the systems equal to 86.012% and 77.7% respectively . A comparison between the two important families of distribution functions, namely, the Weibull and Gamma families is studied. It is found that Weibull method has performed well for decision making .

  12. Air-fuel ratio control of a lean burn Si engine using fuzzy self tuning method

    International Nuclear Information System (INIS)

    Reducing the exhaust emission of an spark ignition engine by means of engine modifications requires consideration of the effects of these modifications on the variations of crankshaft torque and the engine roughness respectively. Only if the roughness does not exceed a certain level the vehicle do not begin to surge. This paper presents a method for controlling the air-fuel ratio for a lean burn engine. Fuzzy rules and reasoning are utilized on-line to determine the control parameters. The main advantages of this method are simple structure and robust performance in a wide range of operating conditions. A non-linear model of an Si engine with the engine torque irregularity simulation is used in this study

  13. A DETAILED EXPERIMENTAL INVESTIGATION ON HOT AIR ASSISTED TURPENTINE DIRECT INJECTED COMPRESSION IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    KARTHIKEYAN.R,

    2010-10-01

    Full Text Available In the present investigation, a diesel engine modified for turpentine direct injection (TDI has been tested to study turpentine oil behavior in compression ignition engine. Since, turpentine possesses low cetane number fails to auto ignite while DI. Hence, the test engine was modified to supply hot air during suction stroke, whichhelps to auto-ignite the injected turpentine. The engine with this facility was operated using turpentine under various load conditions and at various intake temperatures. The results of the investigation were proved that turpentine could be direct injectable in a regular diesel engine after little engine modification. This method showed almost same BTE at full load compared to standard diesel operation. Except NOx emission other emissions were found closer to diesel baseline operation. This mode offered almost 50% smoke free operation at all loads compared to standard diesel operation. Also, this method successfully proved the complete replacement of diesel fuel by turpentine oil.

  14. Estimation of Engine Intake Air Mass Flow using a generic Speed-Density method

    Directory of Open Access Journals (Sweden)

    Vojtíšek Michal

    2014-10-01

    Full Text Available Measurement of real driving emissions (RDE from internal combustion engines under real-world operation using portable, onboard monitoring systems (PEMS is becoming an increasingly important tool aiding the assessment of the effects of new fuels and technologies on environment and human health. The knowledge of exhaust flow is one of the prerequisites for successful RDE measurement with PEMS. One of the simplest approaches for estimating the exhaust flow from virtually any engine is its computation from the intake air flow, which is calculated from measured engine rpm and intake manifold charge pressure and temperature using a generic speed-density algorithm, applicable to most contemporary four-cycle engines. In this work, a generic speed-density algorithm was compared against several reference methods on representative European production engines - a gasoline port-injected automobile engine, two turbocharged diesel automobile engines, and a heavy-duty turbocharged diesel engine. The overall results suggest that the uncertainty of the generic speed-density method is on the order of 10% throughout most of the engine operating range, but increasing to tens of percent where high-volume exhaust gas recirculation is used. For non-EGR engines, such uncertainty is acceptable for many simpler and screening measurements, and may be, where desired, reduced by engine-specific calibration.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Traditional technologies of fuels production for air-jet engines

    Directory of Open Access Journals (Sweden)

    Бойченко С. В.

    2013-07-01

    Full Text Available Available energy resources for various fuels, mainly for gas-turbine engines are presented in the given article. Traditional technologies for jet fuels production from nonrenewable raw materials, such as crude oil, coal, natural gas, oil-shales and others are analyzed in details. Cause and effect relationship between production and use of such fuels and their impact on natural environment is defined. The timeliness and necessity for development of alternative technologies of aviation biofuels production are determined in the given article.

  17. 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.

  18. An inventory of aeronautical ground research facilities. Volume 2: Air breathing engine test facilities

    Science.gov (United States)

    Pirrello, C. J.; Hardin, R. D.; Heckart, M. V.; Brown, K. R.

    1971-01-01

    The inventory covers free jet and direct connect altitude cells, sea level static thrust stands, sea level test cells with ram air, and propulsion wind tunnels. Free jet altitude cells and propulsion wind tunnels are used for evaluation of complete inlet-engine-exhaust nozzle propulsion systems under simulated flight conditions. These facilities are similar in principal of operation and differ primarily in test section concept. The propulsion wind tunnel provides a closed test section and restrains the flow around the test specimen while the free jet is allowed to expand freely. A chamber of large diameter about the free jet is provided in which desired operating pressure levels may be maintained. Sea level test cells with ram air provide controlled, conditioned air directly to the engine face for performance evaluation at low altitude flight conditions. Direct connect altitude cells provide a means of performance evaluation at simulated conditions of Mach number and altitude with air supplied to the flight altitude conditions. Sea level static thrust stands simply provide an instrumented engine mounting for measuring thrust at zero airspeed. While all of these facilities are used for integrated engine testing, a few provide engine component test capability.

  19. Simulation, experimental validation and kinematic optimization of a Stirling engine using air and helium

    International Nuclear Information System (INIS)

    A Stirling engine with nominal output power of 1 kW is tested using air and helium as working gases. The influence of working pressure, engine speed and temperature of the hot source is studied, analyzing instantaneous gas pressure as well as instantaneous and stationary temperature at different positions to derive the effective power. A zero dimensional finite-time thermodynamic, three zones model of a generic Stirling engine is developed and successfully validated against experimental gas temperature and pressure in each zone, providing the effective power. This validation underlines the interest of different working gases as well as different geometric configurations for different applications. Furthermore, the validated model allows parametric studies of the engine, with regard to geometry, working gas and engine kinematics. It is used in order to optimize the kinematic of a Stirling engine for different working points and gases. - Highlights: • A Stirling engine of 1 kW is tested using air and helium as working gas. • Effects of working pressure, speed and temperature on power are studied. • A zero dimensional finite-time thermodynamic, three zones model of it is validated. • The validated model is used for parametric studies and optimization of the engine

  20. Vibration survey of internal combustion engines for use on unmanned air vehicles

    International Nuclear Information System (INIS)

    This paper describes the method, the procedure and data results of engine vibration test which is carried out on engines for use on unmanned air vehicles. The paper focuses on the testing of rotating propulsion systems powered by an internal combustion engine which is composed of main rotating components such as the alternator, gearbox, propeller , dampers and couplings. Three measurement methods for measuring torsional and lateral vibrations are presented: a. Gear tooth pulse signal. b. Shaft Strain Gage. c. Laser Displacement Sensors The paper also presents data from tests which were performed using each method and discusses the applications, the advantages and disadvantages of each method

  1. Ambient air cooling arrangement having a pre-swirler for gas turbine engine blade cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ching-Pang; Tham, Kok-Mun; Schroeder, Eric; Meeroff, Jamie; Miller, Jr., Samuel R; Marra, John J

    2015-01-06

    A gas turbine engine including: an ambient-air cooling circuit (10) having a cooling channel (26) disposed in a turbine blade (22) and in fluid communication with a source (12) of ambient air: and an pre-swirler (18), the pre-swirler having: an inner shroud (38); an outer shroud (56); and a plurality of guide vanes (42), each spanning from the inner shroud to the outer shroud. Circumferentially adjacent guide vanes (46, 48) define respective nozzles (44) there between. Forces created by a rotation of the turbine blade motivate ambient air through the cooling circuit. The pre-swirler is configured to impart swirl to ambient air drawn through the nozzles and to direct the swirled ambient air toward a base of the turbine blade. The end walls (50, 54) of the pre-swirler may be contoured.

  2. Simulation of 3D Flow in Turbine Blade Rows including the Effects of Coolant Ejection

    Institute of Scientific and Technical Information of China (English)

    Jian-Jun LIU; Bai-Tao AN; Yun-Tao ZENG

    2008-01-01

    This paper describes the numerical simulation of three-dimensional viscous flows in air-cooled turbine blade rows with the effects of coolant ejection. A TVD Navier-Stokes flow solver incorporated with Baldwin-Lomax turbulence model and multi-grid convergence acceleration algorithm are used for the simulation. The influences of coolant ejection on the main flow are accounted by volumetric coolant source terms. Numerical results for a four-stage turbine are presented and discussed.

  3. Urban air quality improvement by using a CNG lean burn engine for city buses

    NARCIS (Netherlands)

    Merétei, T.; Ling, J.A.N. van; Havenith, C.

    1998-01-01

    The use of compressed natural gas (CNG)-fuelled lean-burn city bus engines has a significant potential for air quality improvement in urban areas. Particularly important is the reduction of NO, as well as particulate and non regulated HC-emissions. For this reason, a CNG-fuelled, lean-burn, turbocha

  4. The influence of air-fuel ratio on mixture parameters in port fuel injection engines

    Directory of Open Access Journals (Sweden)

    Adrian Irimescu

    2008-10-01

    Full Text Available Nowadays, research in the internal combustion engine field is focusing on detailed understanding of the processes that take place in certain parts of the aggregate, and can have a great influence on the engine’s performance and pollution levels. Such research is developed in this paper, in which using a numerical method based on the i-x air-fuel diagram, one can simulate a series of values for pressure, temperature and intake air humidity before and after mixture formation takes place in a spark ignition engine inlet port. The aim is to evaluate the final temperature of the air-fuel mixture near the inlet valve and evaluating the main factors of influence on the homogeneity of the mixture.

  5. Simulation and experimental study of electro-pneumatic valve used in air-powered engine

    Institute of Scientific and Technical Information of China (English)

    Ping-lu CHEN; Xiao-li YU; Lin LIU

    2009-01-01

    To evaluate the performance of newly designed electro-pneumatic valves (EPVs) for the air-powered engine (APE) and study laws of parameters affecting them, a simulation model was established based on the thermodynamics and mechanics theories. Experiments were set up to determine the instantaneous effective orifice area of solenoid valve by the constant volume discharge method. The simulation model was also validated by comparing the measured displacement curve with the simulated displacement curve of the valve in the pressure of 0.16 and 0.49 MPa. Simulation and experimental results showed that maximum working frequency of the designed EPV could reach 30 Hz corresponding to 2000 r/rain of engine rotating speed. Based on simulation results, impacts of temperature and pressure of control air on delay time, full opening/closing time and seating velocity of EPV were analyzed. The simulation model could also act as EPV simulation prototype in designing the air exchange control system of APE.

  6. Performance Investigation of Automobile Radiator Operated with ZnFe2O4 Nano Fluid based Coolant

    Directory of Open Access Journals (Sweden)

    Tripathi Ajay

    2015-01-01

    Full Text Available The cooling system of an Automobile plays an important role in its performance, consists of two main parts, known as radiator and fan. Improving thermal efficiency of engine leads to increase the engine's performance, decline the fuel consumption and decrease the pollution emissions. Water and ethylene glycol as conventional coolants have been widely used in radiators of an automotive industry for many years. These heat transfer fluids offer low thermal conductivity. With the advancement of nanotechnology, the new generation of heat transfer fluids called, “nanofluids” have been developed and researchers found that these fluids offer higher thermal conductivity compared to that of conventional coolants. This study focused on the preparation of Zinc based nanofluids (ZnFe2O4 using chemical co-precipitation method and its application in an automotive cooling system along with mixture of ethylene glycol and water (50:50. Relevant input data, nanofluids properties and empirical correlations were obtained from literatures to investigate the heat transfer enhancement of an automotive car radiator operated with nano fluid-based coolants. It was observed that, overall heat transfer coefficient and heat transfer rate in engine cooling system increased with the usage of nanofluids (with ethylene glycol the base-fluid compared to ethylene glycol (i.e. base-fluid alone. It is observed that, about 78% of heat transfer enhancement could be achieved with the addition of 1% ZnFe2O4 particles in a base fluid at the Reynolds number of 84.4x103 and 39.5x103 for air and coolant respectively

  7. AN ANALYSIS OF PETROL - COMPRESSED AIR POWERED INTERNAL COMBUSTION ENGINE: A HYBRID ENGINE CONCEPT

    OpenAIRE

    Lalit Kumar*, Dharmendra Patel, Vinod Sehrawat, Tarun Gupta

    2016-01-01

    Nowadays environment pollution becomes a much serious issue in the world. Vehicles’ exhaust product is one of the major source of environmental pollution. The engine combustion products are causing the greenhouse effect, acid rains, ozone layer depletion and some other pollution. On the other hand, many study research on fossil fuel in the previous years, observed that if the oil is consumed at this rates, 81% of the entire available resource will be consumed very soon. So now we begin ...

  8. Visualization of Air Particle Dynamics in an Engine Inertial Particle Separator

    Science.gov (United States)

    Wolf, Jason; Zhang, Wei

    2015-11-01

    Unmanned Aerial Vehicles (UAVs) are regularly deployed around the world in support of military, civilian and humanitarian efforts. Due to their unique mission profiles, these advanced UAVs utilize various internal combustion engines, which consume large quantities of air. Operating these UAVs in areas with high concentrations of sand and dust can be hazardous to the engines, especially during takeoff and landing. In such events, engine intake filters quickly become saturated and clogged with dust particles, causing a substantial decrease in the UAVs' engine performance and service life. Development of an Engine Air Particle Separator (EAPS) with high particle separation efficiency is necessary for maintaining satisfactory performance of the UAVs. Inertial Particle Separators (IPS) have been one common effective method but they experience complex internal particle-laden flows that are challenging to understand and model. This research employs an IPS test rig to simulate dust particle separation under different flow conditions. Soda lime glass spheres with a mean diameter of 35-45 microns are used in experiments as a surrogate for airborne particulates encountered during flight. We will present measurements of turbulent flow and particle dynamics using flow visualization techniques to understand the multiphase fluid dynamics in the IPS device. This knowledge can contribute to design better performing IPS systems for UAVs. Cleveland State University, Cleveland, Ohio, 44115.

  9. EVALUATION OF FILTRATION AND DISTILLATION METHODS FOR RECYCLING AUTOMOTIVE COOLANT.

    Science.gov (United States)

    This evaluation addresses the product quality, waste reduction, and economic issues involved in recycling automotive and heavy-duty engine coolants at a New Jersey Department of Transportation garage. The specific recycling units evaluated are based on the technologies of filtrat...

  10. Emissions of an AVCO Lycoming 0-320-DIAD air cooled light aircraft engine as a function of fuel-air ratio, timing, and air temperature and humidity

    Science.gov (United States)

    Meng, P. R.; Skorobatckyi, M.; Cosgrove, D. V.; Kempke, E. E., Jr.

    1976-01-01

    A carbureted aircraft engine was operated over a range of test conditions to establish the exhaust levels over the EPA seven-mode emissions cycle. Baseline (full rich production limit) exhaust emissions at an induction air temperature of 59 F and near zero relative humidity were 90 percent of the EPA standard for HC, 35 percent for NOx, and 161 percent for CO. Changes in ignition timing around the standard 25 deg BTDC from 30 deg BTDC to 20 deg BTDC had little effect on the exhaust emissions. Retarding the timing to 15 deg BTDC increased both the HC and CO emissions and decreased NOx emissions. HC and CO emissions decreased as the carburetor was leaned out, while NOx emissions increased. The EPA emission standards were marginally achieved at two leanout conditions. Variations in the quantity of cooling air flow over the engine had no effect on exhaust emissions. Temperature-humidity effects at the higher values of air temperature and relative humidity tested indicated that the HC and CO emissions increased significantly, while the NOx emissions decreased.

  11. Treatment of mixed waste coolant

    International Nuclear Information System (INIS)

    The primary processes used at Lawrence Livermore National Laboratory (LLNL) for treatment of radioactively contaminated machine coolants are industrial waste treatment and in situ carbon adsorption. These two processes simplify approaches to meeting the sanitary sewer discharge limits and subsequent Land Disposal Restriction criteria for hazardous and mixed wastes (40 CFR 268). Several relatively simple technologies are used in industrial water treatment. These technologies are considered Best Demonstrated Available Technologies, or BDAT, by the Environmental Protection Agency. The machine coolants are primarily aqueous and contain water soluble oil consisting of ethanol amine emulsifiers derived from fatty acids, both synthetic and natural. This emulsion carries away metal turnings from a part being machined on a lathe or other machining tool. When the coolant becomes spent, it contains chlorosolvents carried over from other cutting operations as well as a fair amount of tramp oil from machine bearings. This results in a multiphasic aqueous waste that requires treatment of metal and organic contaminants. During treatment, any dissolved metals are oxidized with hydrogen peroxide. Once oxidized, these metals are flocculated with ferric sulfate and precipitated with sodium hydroxide, and then the precipitate is filtered through diatomaceous earth. The emulsion is broken up by acidifying the coolant. Solvents and oils are adsorbed using powdered carbon. This carbon is easily separated from the remaining coolant by vacuum filtration

  12. Non-self-sustained microwave discharge and the concept of a microwave air jet engine

    International Nuclear Information System (INIS)

    A new type of microwave discharge - near-surface non-self-sustained discharge (NSND) - has been realized and investigated. A physical model of this discharge is presented. For the first time NSND application for microwave air jet engines has been proposed. Measurements under laboratory conditions modelling the microwave air jet engine operation shows the qualitative agreement between the model of NSND and actual processes near the target irradiated by a powerful microwave beam. Characteristic dependences of recoil momentum of target on the background pressure and microwave pulse duration obtained in experiments are presented. Measured cost of thrust produced by the NSND is no more than 3.0 kW N-1, which is close to the predicted values

  13. The aerodynamic effects of wheelspace coolant injection into the mainstream flow of a high pressure gas turbine

    Science.gov (United States)

    McLean, Christopher Elliot

    Modern gas turbine engines operate with mainstream gas temperatures exceeding 1450°C in the high-pressure turbine stage. Unlike turbine blades, rotor disks and other internal components are not designed to withstand the extreme temperatures found in mainstream flow. In modern gas turbines, cooling air is pumped into the wheelspace cavities to prevent mainstream gas ingestion and then exits through a seal between the rotor and the nozzle guide vane (NGV) thereby mixing with the mainstream flow. The primary purpose for the wheelspace cooling air is the cooling of the turbine wheelspace. However, secondary effects arise from the mixing of the spent cooling air with the mainstream flow. The exiting cooling air is mixed with the hot mainstream flow effecting the aerodynamic and performance characteristics of the turbine stage. The physics underlying this mixing process and its effects on stage performance are not yet fully understood. The relative aerodynamic and performance effects associated with rotor - NGV gap coolant injections were investigated in the Axial Flow Turbine Research Facility (AFTRF) of the Center for Gas Turbines and Power of The Pennsylvania State University. This study quantifies the secondary effects of the coolant injection on the aerodynamic and performance character of the turbines main stream flow for root injection, radial cooling, and impingement cooling. Measurement and analysis of the cooling effects were performed in both stationary and rotational frames of reference. The AFTRF is unique in its ability to perform long duration cooling measurements in the stationary and rotating frames. The effects of wheelspace coolant mixing with the mainstream flow on total-to-total efficiency, energy transport, three dimensional velocity field, and loading coefficient were investigated. Overall, it was found that a small quantity (1%) of cooling air can have significant effects on the performance character and exit conditions of the high pressure stage

  14. Pneumatic hybridization of a diesel engine using compressed air storage for wind-diesel energy generation

    International Nuclear Information System (INIS)

    In this paper, we are studying an innovative solution to reduce fuel consumption and production cost for electricity production by Diesel generators. The solution is particularly suitable for remote areas where the cost of energy is very high not only because of inherent cost of technology but also due to transportation costs. It has significant environmental benefits as the use of fossil fuels for electricity generation is a significant source of GHG (Greenhouse Gas) emissions. The use of hybrid systems that combine renewable sources, especially wind, and Diesel generators, reduces fuel consumption and operation cost and has environmental benefits. Adding a storage element to the hybrid system increases the penetration level of the renewable sources, that is the percentage of renewable energy in the overall production, and further improves fuel savings. In a previous work, we demonstrated that CAES (Compressed Air Energy Storage) has numerous advantages for hybrid wind-diesel systems due to its low cost, high power density and reliability. The pneumatic hybridization of the Diesel engine consists to introduce the CAES through the admission valve. We have proven that we can improve the combustion efficiency and therefore the fuel consumption by optimizing Air/Fuel ratio thanks to the CAES assistance. As a continuation of these previous analyses, we studied the effect of the intake pressure and temperature and the exhaust pressure on the thermodynamic cycle of the diesel engine and determined the values of these parameters that will optimize fuel consumption. -- Highlights: ► Fuel economy analysis of a simple pneumatic hybridization of the Diesel engine using stored compressed air. ► Thermodynamic analysis of the pneumatic hybridization of diesel engines for hybrid wind-diesel energy systems. ► Analysis of intake pressure and temperature of compressed air and exhaust pressure on pressure/temperature during Diesel thermodynamic cycle. ► Direct admission of

  15. Rotary engine cooling system

    Science.gov (United States)

    Jones, Charles (Inventor); Gigon, Richard M. (Inventor); Blum, Edward J. (Inventor)

    1985-01-01

    A rotary engine has a substantially trochoidal-shaped housing cavity in which a rotor planetates. A cooling system for the engine directs coolant along a single series path consisting of series connected groups of passages. Coolant enters near the intake port, passes downwardly and axially through the cooler regions of the engine, then passes upwardly and axially through the hotter regions. By first flowing through the coolest regions, coolant pressure is reduced, thus reducing the saturation temperature of the coolant and thereby enhancing the nucleate boiling heat transfer mechanism which predominates in the high heat flux region of the engine during high power level operation.

  16. Data center coolant switch

    Science.gov (United States)

    Iyengar, Madhusudan K.; Parida, Pritish R.; Schultz, Mark D.

    2015-10-06

    A data center cooling system is operated in a first mode; it has an indoor portion wherein heat is absorbed from components in the data center, and an outdoor heat exchanger portion wherein outside air is used to cool a first heat transfer fluid (e.g., water) present in at least the outdoor heat exchanger portion of the cooling system during the first mode. The first heat transfer fluid is a relatively high performance heat transfer fluid (as compared to the second fluid), and has a first heat transfer fluid freezing point. A determination is made that an appropriate time has been reached to switch from the first mode to a second mode. Based on this determination, the outdoor heat exchanger portion of the data cooling system is switched to a second heat transfer fluid, which is a relatively low performance heat transfer fluid, as compared to the first heat transfer fluid. It has a second heat transfer fluid freezing point lower than the first heat transfer fluid freezing point, and the second heat transfer fluid freezing point is sufficiently low to operate without freezing when the outdoor air temperature drops below a first predetermined relationship with the first heat transfer fluid freezing point.

  17. Adaptive critic learning techniques for engine torque and air-fuel ratio control.

    Science.gov (United States)

    Liu, Derong; Javaherian, Hossein; Kovalenko, Olesia; Huang, Ting

    2008-08-01

    A new approach for engine calibration and control is proposed. In this paper, we present our research results on the implementation of adaptive critic designs for self-learning control of automotive engines. A class of adaptive critic designs that can be classified as (model-free) action-dependent heuristic dynamic programming is used in this research project. The goals of the present learning control design for automotive engines include improved performance, reduced emissions, and maintained optimum performance under various operating conditions. Using the data from a test vehicle with a V8 engine, we developed a neural network model of the engine and neural network controllers based on the idea of approximate dynamic programming to achieve optimal control. We have developed and simulated self-learning neural network controllers for both engine torque (TRQ) and exhaust air-fuel ratio (AFR) control. The goal of TRQ control and AFR control is to track the commanded values. For both control problems, excellent neural network controller transient performance has been achieved. PMID:18632389

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

    International Nuclear Information System (INIS)

    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 oC to 24 oC. 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.

  19. Power generation from a new air-based Marnoch heat engine

    International Nuclear Information System (INIS)

    This paper examines the performance of a new Marnoch heat engine, which uses dry air and a pneumatic piston assembly to convert thermal energy to electricity. The system has unique capabilities of operating over temperature differentials less than 100 K. Unlike a common Stirling engine, the heat exchangers and piston assembly are not co-located, which is beneficial for positioning of heat exchangers in various configurations. This paper presents an operational laboratory-scale, proof-of-concept Marnoch heat engine (MHE), including its performance and power generation capabilities. It also presents a thermodynamic analysis of the system. Based on the MHE results, component modifications are made to improve its performance. The configuration has an efficiency of about thirty percent of a Carnot heat engine operating in the temperature range between 272 K and 372 K. Experimental data is acquired to provide verification of the predictive model, as well as demonstration of the MHE’s capabilities for efficient generation of electricity from waste heat sources. -- Highlights: ► This paper presents a thermodynamic analysis and experimental data for a Marnoch heat engine (MHE). ► The MHE has an efficiency of about thirty percent of a Carnot heat engine between 272 K and 372 K. ► Experimental data is successfully compared to the predictive model. ► The MHE shows promising performance for generation of electricity from waste heat sources.

  20. Study on Air Intake and Cooling System for Marine Diesel Engine

    Directory of Open Access Journals (Sweden)

    Su Shaohui

    2013-09-01

    Full Text Available Regarding the power, the efficiency and the discharge questions of the low-speed diesel engine, this article studied emphatically the Miller cycle, the analysis technology for the air intake system, and the matching technology for the intake and the exhaust. On the foundation of the twin inlet structure the paper analyzed the intake swirl control area and its influence to the gas charging efficiency, proposed the design scheme for the invariable intake swirl control system. By matching reasonably the intake, the exhaust, and the injection process of the diesel engine, the combustion process is further optimized to satisfy the target request for the complete machine’s power, fuel oil efficiency and emission. Aiming at the high-power low-speed marine diesel engine, the paper analyzes the impact of the diesel engine’s cooling to the power, economy and NOx’s emission, studies the variable flow control method and system of the diesel engine cooling water and proposes the scheme setting up the intercooler system and the body cooling system independently in the diesel engine. The results show that the methods and systems are better to improve the engine power, reduce the fuel consumption and NOx’s emission.    

  1. Air purging unit for an optical pyrometer of a gas turbine engine

    International Nuclear Information System (INIS)

    In order to measure the temperature of the mid-span first stage rotor blade of a gas turbine engine, an optical pyrometer is mounted in the inner casing of the gas turbine engine and includes an elongated sight tube extending from the optical lens of the pyrometer and through the wall of the engine separating the inner casing from the rotor. The sight tube includes an array of spaced apertures extending therethrough in the vicinity of the optical lens, with each aperture extending at an acute angle to the longitudinal axis of the sight tube away from the optical lens. Pressurized air within the inner casing passes through the array of apertures and effectively forms a conically-shaped fluid screen for preventing smoke, dust, fumes, or other contaminants from contaminating the optical lens. A second fluid screen may be provided by mounting the free end of the sight tube in an enlarged opening in the wall of the engine casing, whereby a secondary, generally cylindrical flow of air is developed for shielding the open end of the sight tube. The upstream edge of the sight tube may project into the flow path of the combustion gases flowing to the rotor stage whereby such combustion gases will be deflected and directed around the circumference of the sight tube to further inhibit contaminants from entering the sight tube and contaminating the optical lens

  2. Evaluation of core inlet coolant temperature of HTTR

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Research Institute (JAERI) has been planning the construction of High Temperature Engineering Test Reactor (HTTR) which in 30MW in thermal power, 850degC and 950degC in outlet coolant temperature and 40kg/cm2G in primary coolant pressure. In the HTTR, coolant flows upward in channels between core and Reactor Pressure Vessel (RPV), then mixed in the upper plenum and flows into the core. This report presents the evaluation results of the core inlet temperature, which is a fundamental value of maximum fuel temperature calculation. Temperature behavior at the core side channel is calculated by FEM code and temperature mixing characteristics is calculated by thermal-hydraulic code 'STREAM'. The evaluation error of core inlet temperature is one of the hot spot factors for the maximum fuel temperature calculation. (author)

  3. Coolant and ambient temperature control for chillerless liquid cooled data centers

    Science.gov (United States)

    Chainer, Timothy J.; David, Milnes P.; Iyengar, Madhusudan K.; Parida, Pritish R.; Simons, Robert E.

    2016-02-02

    Cooling control methods include measuring a temperature of air provided to a plurality of nodes by an air-to-liquid heat exchanger, measuring a temperature of at least one component of the plurality of nodes and finding a maximum component temperature across all such nodes, comparing the maximum component temperature to a first and second component threshold and comparing the air temperature to a first and second air threshold, and controlling a proportion of coolant flow and a coolant flow rate to the air-to-liquid heat exchanger and the plurality of nodes based on the comparisons.

  4. Direct Air Capture of CO2 - an Overview of Carbon Engineering's Technology and Pilot Plant Development

    Science.gov (United States)

    Holmes, G.; Corless, A.

    2014-12-01

    At Carbon Engineering, we are developing and commercializing technology to scrub CO2 directly from atmospheric air at industrial scale. By providing atmospheric CO2 for use in fuel production, we can enable production of transportation fuels with ultra-low carbon intensities, which command price premiums in the growing set of constrained fuels markets such as California's LCFS. We are a Calgary based startup founded in 2009 with 10 employees, and we are considered a global leader in the direct air capture (DAC) field. We will review CE's DAC technology, based on a wet-scrubbing "air contactor" which absorbs CO2 into aqueous solution, and a chemical looping "regeneration" component, which liberates pure CO2 from this aqueous solution while re-making the original absorption chemical. CE's DAC tecnology exports purified atmospheric CO2, combined with the combustion CO2 from plant energy usage, as the end product. We will also discuss CE's 2014-2015 end-to-end Pilot Demonstration Unit. This is a $7M technology demonstration plant that CE is building with the help of key industrial partners and equipment vendors. Vendor design and engineering requirements have been used to specify the pilot air contactor, pellet reactor, calciner, and slaker modules, as well as auxiliary systems. These modules will be run for several months to obtain the engineering and performance data needed for subsequent commercial plant design, as well as to test the residual integration risks associated with CE's process. By the time of the AGU conference, the pilot is expected to be in late stages of fabrication or early stages of site installation.

  5. Sodium as a reactor coolant

    International Nuclear Information System (INIS)

    This work is related to the use of sodium as a reactor coolant, to the advantages and problems related to its use, its mechanical, thermophysics, eletronical, magnetic and nuclear properties. It is mainly a bibliographic review, with the aim of gathering the necessary information to persons initiating in the study of sodium and also as reference source. (author)

  6. Original design of coal-bed gas/air control units for engine-generator sets

    Energy Technology Data Exchange (ETDEWEB)

    Qiao Anping [Taiyuan University of Technology, Shanxi Province (China); Li Yunqing; Gao Feng [Beijing University of Aeronautics and Astronautics (China)

    2006-07-01

    An original air/fuel automatic mixing control unit for a coal-bed gas internal combustion engine and its matching generator, which is different from the conventional one, is introduced. The basic design and calculation method of this novel unit are explained. On the basis of these, the units of the 12V190ZDT type engine-generator sets are calculated and designed, machined, and trial-produced. A year's service-test at the Centre of West Coal Mine Construction shows that the performances of these devices are stable and reliable, and that this method could solve many practical problems that the old unit could not; for instance, working with mid-low concentration of coal-seam gas. They also fill a gap in the field of design, calculation, development, and application of coal-bed gas devices; the economic and social benefits are also truly remarkable. Therefore, the design and calculation method obtained in this article are important for engineering applications. This paper also offers a theoretical basis for the design and development of coal-seam gas engines or sets of engine-generator. (author)

  7. Original design of coal-bed gas/air control units for engine-generator sets

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, A.P.; Li, Y.Q.; Gao, F. [Beijing University of Aeronautic & Astronautic, Beijing (China)

    2006-03-15

    An original air/fuel automatic mixing control unit for a coal-bed gas internal combustion engine and its matching generator, which is different from the conventional one, is introduced. The basic design and calculation method of this novel unit are explained. On the basis of these, the units of the 12V190ZDT type engine-generator sets are calculated and designed, machined, and trial-produced. A year's service-test at the Centre of West Coal Mine Construction shows that the performances of these devices are stable and reliable, and that this method could solve many practical problems that the old unit could not; for instance, working with mid-low concentration of coal-seam gas. They also fill a gap in the field of design, calculation, development, and application of coal-bed gas devices; the economic and social benefits are also truly remarkable. Therefore, the design and calculation method obtained in this article are important for engineering applications. This paper also offers a theoretical basis for the design and development of coal-seam gas engines or sets of engine-generator.

  8. STUDY OF FLOW IN AIR-INTAKE SYSTEM FOR A SINGLE-CYLINDER GO-KART ENGINE

    Directory of Open Access Journals (Sweden)

    S. A. Sulaiman

    2010-06-01

    Full Text Available Intake-air manifolds have a major effect on a vehicle’s engine performance and emission of noise and pollutants. Differences in engine outputs and applications require different designs of intake-air manifolds in order to achieve the best volumetric efficiency and thus the best engine performance. In the present work, the flow characteristics of air flowing in various designs of air-intake manifold of a 200-cc four-stroke Go-Kart engine are studied. The study is done by three dimensional simulations of the flow of air within six designs of air-intake manifold into the combustion chamber by using commercial CFD software, Fluent version 6.2. The simulation results are validated by an experimental study performed using a flow bench. The study reveals that the variations in the geometry of the air-intake system can result in a difference of up to 20% in the mass flow rate of air entering the combustion chamber.

  9. 76 FR 45011 - Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test...

    Science.gov (United States)

    2011-07-27

    ... Procedures for Aircraft;'' Final Rule, 38 FR 19088, July 17, 1973. \\12\\ U.S. EPA, ``Control of Air Pollution from Aircraft and Aircraft Engines; Emission Standards and Test Procedures;'' Final Rule, 62 FR 25356... Engines; Emission Standards and Test Procedures;'' Final Rule, 70 FR 2521, November 17, 2005. E....

  10. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review

    Science.gov (United States)

    Masiol, Mauro; Harrison, Roy M.

    2014-10-01

    Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.

  11. Los Alamos Controlled Air Incinerator for radioactive waste. Volume II. Engineering design reference manual

    International Nuclear Information System (INIS)

    This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities

  12. Controlled air incinerator for radioactive waste. Volume II. Engineering design references manual

    International Nuclear Information System (INIS)

    This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities

  13. Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Conover, D.R.

    1993-05-01

    In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

  14. EFFECT OF GASOLINE - ETHANOL BLENDS ON PERFORMANCE AND EMISSION CHARACTERISTICS OF A SINGLE CYLINDER AIR COOLED MOTOR BIKE SI ENGINE

    Directory of Open Access Journals (Sweden)

    A. SAMUEL RAJA

    2015-12-01

    Full Text Available This paper investigates the effect of using gasoline-ethanol (GE blends on performance and exhaust emission of a four stroke 150 cc single cylinder air cooled spark ignition (SI engine, without any modifications. Experiments were conducted at part load and different engine speeds ranging from 3000 to 5000 rpm, without and with catalytic converter. Ethanol content was varied from 5 percentage to 20 percentage by volume and four different blends (E5, E10, E15 and E20 were tested. Fuel consumption, engine speed, air fuel ratio, exhaust gas temperature and exhaust emissions were measured during each experiment. Brake thermal efficiency (ηb,th, volumetric efficiency (ηvol, brake specific fuel consumption (BSFC and excess air factor were calculated for each test run. Brake specific fuel consumption, volumetric efficiency and excess air factor increased with ethanol percentage in the blend. Carbon monoxide (CO, hydrocarbon (HC and oxides of nitrogen (NOx emissions decreased with blends.

  15. Study on a Closed-Loop Air-Fuel Control System of Gasoline Engines by Simulation

    Institute of Scientific and Technical Information of China (English)

    张付军; 赵长禄; 黄英; 郝利军

    2003-01-01

    In order to study the factors that influence the air-fuel ratio(A/F), the amplitude and frequency of A/F fluctuation, to reform the control strategy, and to improve the efficiency of three-way catalyst(TWC), a model of closed-loop control system including the engine, air-fuel mixing and transportation, oxygen sensor and controller, etc., is developed. Various factors that influence the A/F control are studied by simulation. The simulation results show that the reference voltage of oxygen sensor will influence the mean value of A/F ratio, the controller parameters will influence the amplitude of A/F fluctuation, and the operating conditions of the engine determine the frequency of A/F fluctuations, the amplitude of A/F fluctuation can be reduced to within demanded values by logical selection of the signal acquisition method and controller parameters. Higher A/F fluctuation frequency under high speed and load can be reduced through software delay in the controller. The A/F closed-loop control system based on the simulation results, accompanied with a rare-earth element TWC, gives a better efficiency of conversion against harmful emissions.

  16. Cardiac arrhythmogenesis in urban air pollution: Optical mapping in a tissue-engineered model

    Science.gov (United States)

    Bien, Harold H.

    Recent epidemiological evidence has implicated particulate matter air pollution in cardiovascular disease. We hypothesized that inflammatory mediators released from lung macrophages after exposure to particulate matter predisposes the heart to disturbances in rhythm. Using a rational design approach, a fluorescent optical mapping system was devised to image spatiotemporal patterns of excitation in a tissue engineered model of cardiac tissue. Algorithms for automated data analysis and characterization of rhythm stability were developed, implemented, and verified. Baseline evaluation of spatiotemporal instability patterns in normal cardiac tissue was performed for comparison to an in-vitro model of particulate matter air pollution exposure. Exposure to particulate-matter activated alveolar macrophage conditioned media resulted in paradoxical functional changes more consistent with improved growth. These findings might be indicative of a "stress" response to particulate-matter induced pulmonary inflammation, or may be specific to the animal model (neonatal rat) employed. In the pursuit of elucidating the proposed pathway, we have also furthered our understanding of fundamental behaviors of arrhythmias in general and established a model where further testing might ultimately reveal the mechanism for urban air pollution associated cardiovascular morbidity.

  17. System Design and Analysis of a Directly Air-Assisted Turbocharged SI Engine with Camshaft Driven Valves

    Directory of Open Access Journals (Sweden)

    Lino Guzzella

    2013-03-01

    Full Text Available The availability of compressed air in combination with downsizing and turbocharging is a promising approach to improve the fuel economy and the driveability of internal combustion engines. The compressed air is used to boost and start the engine. It is generated during deceleration phases by running the engine as a piston compressor. In this paper, a camshaft-driven valve is considered for the control of the air exchange between the tank and the combustion chamber. Such a valve system is cost-effective and robust. Each pneumatic engine mode is realized by a separate cam. The air mass transfer in each mode is analyzed. Special attention is paid to the tank pressure dependence. The air demand in the boost mode is found to increase with the tank pressure. However, the dependence on the tank pressure is small in the most relevant operating region. The air demand of the pneumatic start shows a piecewise continuous dependence on the tank pressure. Finally, a tank sizing method is proposed which uses a quasi-static simulation. It is applied to a compact class vehicle, for which a tank volume of less than 10 L is sufficient. A further reduction of the tank volume is limited by the specifications imposed on the pneumatic start.

  18. Loss-of-coolant accidents with impaired emergency coolant injection

    International Nuclear Information System (INIS)

    This report describes work on loss-of-coolant accidents in CANDU reactors in which emergency coolant injection is indefinitely delayed. Two situations are considered, one in which additional heat sinks (moderator, moderator cooling system, etc.) are available and effective and the other in which they are not. For the situation in which additional heat sinks are available, the computer program IMPECC has been used for the analysis. Certain corrections and modifications to IMPECC are described and recommendations on the maximum time steps to use are given. For CANDU reactors in which calandria tubes remain submerged, should local CHF occur when a pressure tube sags onto a calandria tube, which is highly improbable, the dry patch caused would not spread beyond 100 and rewetting would occur rapidly. Calandria tube and pressure tube integrity will almost certainly be maintained. This conclusion is not affected even if the contact strip between pressure and calandria tubes is very wide, which is unlikely. For the situation in which additional heat sinks are not available, a simplified event tree has been developed to examine possible accident sequences. Two accident sequences have been selected for study: loss of moderator cooling system and loss of moderator heat sink. A detailed description of the analytical steps for the loss of moderator cooling system accident sequence is given

  19. Thermodynamic modelling of PWR coolant

    International Nuclear Information System (INIS)

    Corrosion products released from PWR and VVER primary circuit surface oxides are transported in the coolant to the core, where they deposit and are activated to form radioactive corrosion products, which can be re-released to re-deposit on out-of-core surfaces. Spinel solubilities vary with the pH, temperature and sometimes the hydrogen concentration of the coolant. This paper describes the development of an equilibrium thermodynamic model to predict such changes, and discusses the extent of the available solubility data for Fe, Ni, Co and Zn oxides. Results are described on the relative solubility of Fe and Ni under both normal operating conditions and during shutdown/start-up, and on the relative stabilities of stoichiometric and non-stoichiometric zinc ferrite spinels. Comparison of the calculated corrosion product concentrations with reactor measurements indicates that, in reactors with low Ni content in the steam generator alloys, the concentration of Ni in the coolant is limited by its availability in the surface oxide. In reactors with high-Ni alloys, the circulating Ni concentrations may be dominated by colloidal material. The calculated changes in Ni and Fe concentrations during the acid-reducing phase of shutdown are in reasonable agreement with measurements from Sizewell B. The paper highlights the need for a more comprehensive open corrosion product data base, the need to consider both boiling and radiolysis in the core on corrosion product solubility in different parts of the primary circuit and, finally, the importance of kinetic factors at low temperature behaviour during shutdown and start-up. (author)

  20. Thermodynamic modelling of PWR coolant

    International Nuclear Information System (INIS)

    Spinel solubilities on PWR primary circuit surfaces vary with temperature, pH and coolant H2 concentration. The available solubility data are discussed for Fe, Ni, Co and Zn oxides, and species are identified where data are very limited or absent. An equilibrium thermodynamic model is described to predict the solubility, and results are described predicting relative Fe and Ni solubility under normal operating conditions and during shutdown/startup. The relative stabilities of stoichiometric and non-stoichiometric zinc ferrite spinels are also considered. (R.P.)

  1. Study on diesel cylinder-head cooling using nanofluid coolant with jet impingement

    Directory of Open Access Journals (Sweden)

    Su Zhong-Gen

    2015-01-01

    Full Text Available To improve the heat-transfer performance of a diesel-engine cylinder head, nanofluid coolant as a new fluid was investigated, and jet impingement technology was then used to study on how to better improve heat-transfer coefficient at the nose bridge area in the diesel-engine cylinder head. Computational fluid dynamic simulation and experiments results demonstrated that using the same jet impingement parameters, the different volume shares of nanofluids showed better cooling effect than traditional coolant, but the good effect of the new cooling method was unsuitable for high volume share of nanofluid. At the same volume share of nanofluid, different jet impingement parameters such as jet angles showed different heat-transfer performance. This result implies that a strong association exists between jet impingement parameters and heat-transfer coefficient. The increase in coolant viscosity of the nanofluid coolant using jet impingement requires the expense of more drive-power cost.

  2. Modeling and Control Systems Design for Air Intake System of Diesel Engines for Improvement of Transient Characteristic

    Science.gov (United States)

    Ejiri, Arata; Sasaki, Jun; Kinoshita, Yusuke; Fujimoto, Junya; Maruyama, Tsugito; Shimotani, Keiji

    For the purpose of contributing to global environment protection, several research studies have been conducted involving clean-burning diesel engines. In recent diesel engines with Exhaust Gas Recirculation (EGR) systems and a Variable Nozzle Turbocharger (VNT), mutual interference between EGR and VNT has been noted. Hence, designing and adjusting control of the conventional PID controller is particularly difficult at the transient state in which the engine speed and fuel injection rate change. In this paper, we formulate 1st principal model of air intake system of diesel engines and transform it to control oriented model including an engine steady state model and a transient model. And we propose a model-based control system with the LQR Controller, Saturation Compensator, the Dynamic Feed-forward and Disturbance Observer using a transient model. Using this method, we achieved precise reference tracking and emission reduction in transient mode test with the real engine evaluations.

  3. Increasing reliability of gas-air systems of piston and combined internal combustion engines by improving thermal and mechanic flow characteristics

    Science.gov (United States)

    Brodov, Yu. M.; Grigor'ev, N. I.; Zhilkin, B. P.; Plotnikov, L. V.; Shestakov, D. S.

    2015-12-01

    Results of experimental study of thermal and mechanical characteristics of gas exchange flow in piston and combined engines are presented. Ways for improving intake and exhaust processes to increase reliability of gas-air engine systems are proposed.

  4. Multi-dimensional modelling of spray, in-cylinder air motion and fuel–air mixing in a direct-injection engine

    Indian Academy of Sciences (India)

    N Abani; S Bakshi; R V Ravikrishna

    2007-10-01

    In this work, three-dimensional fuel–air mixing inside a conventional spark ignition engine cylinder is simulated under direct injection conditions. The motivation is to explore retrofitting of conventional engines for direct injection to take advantage of low emissions and high thermal efficiency of the direct injection concept. Fuel–air mixing is studied at different loads by developing and applying a model based on the Lagrangian-drop and Eulerian-fluid (LDEF) procedure for modelling the two-phase flow. The Taylor Analogy Breakup (TAB) model for modelling the hollow cone spray and appropriate models for droplet impingement, drag and evaporation are used. Moving boundary algorithm and two-way interaction between both phases are implemented. Fuel injection timing and quantity is varied with load. Results show that near-stoichiometric fuel–air ratio region is observed at different locations depending on the load. The model developed serves to predict the fuel–air mixing spatially and temporally, and hence is a useful tool in design and optimization of direct injection engines with regards to injector and spark plug locations. Simulations over a range of speed and load indicate the need for a novel ignition strategy involving dual spark plugs and also provide guidelines in deciding spark plug locations.

  5. Prediction of cold start hydrocarbon emissions of air cooled two wheeler spark ignition engines by simple fuzzy logic simulation

    Directory of Open Access Journals (Sweden)

    Samuel Raja Ayyanan

    2014-01-01

    Full Text Available The cold start hydrocarbon emission from the increasing population of two wheelers in countries like India is one of the research issues to be addressed. This work describes the prediction of cold start hydrocarbon emissions from air cooled spark ignition engines through fuzzy logic technique. Hydrocarbon emissions were experimentally measured from test engines of different cubic capacity, at different lubricating oil temperature and at different idling speeds with and without secondary air supply in exhaust. The experimental data were used as input for modeling average hydrocarbon emissions for 180 seconds counted from cold start and warm start of gasoline bike engines. In fuzzy logic simulation, member functions were assigned for input variables (cubic capacity and idling rpm and output variables (average hydrocarbon emission for first 180 seconds at cold start and warm start. The knowledge based rules were adopted from the analyzed experimental data and separate simulations were carried out for predicting hydrocarbon emissions from engines equipped with and without secondary air supply. The simulation yielded the average hydrocarbon emissions of air cooled gasoline engine for a set of given input data with accuracy over 90%.

  6. Liquid Metal Coolant Technology for Fast Reactors

    International Nuclear Information System (INIS)

    In the paper presented are results of comparative analysis and the choice of liquid metal coolants for fast reactors, the current status of studies on the physical chemistry and technology of sodium coolants for fast neutron reactors and heavy liquid metal coolants, namely, lead-bismuth and lead for fast reactors and accelerator driven systems. There are descriptions of devices designed for control of the impurities in sodium coolants and their removal as well as methods of heavy liquid metal coolant quality control, removal of impurities from heavy liquid metal coolants and the steel surface of components of nuclear power plants (NPPs) and relevant equipment. Attention is given to the issues of modelling of impurity mass transfer in liquid metal coolants and designing new liquid metal coolants for NPPs. Results of the analysis of NPP abnormal operating conditions are presented. The adopted design approaches assure reliable protection against accidents. Up to now, about 200 reactor-years of sodium cooled fast reactor operation and about 80 reactor-years of submarine reactor operation have been gained. The new goals for sodium and heavy liquid metal coolant technology have been formulated as applied to the new generation fast reactors. (author)

  7. Cleaning of aluminum after machining with coolants

    International Nuclear Information System (INIS)

    An x-ray photoemission spectroscopic study was undertaken to compare the cleaning of the Advanced Photon Source (APS) aluminum extrusion storage ring vacuum chambers after machining with and without water soluble coolants. While there was significant contamination left by the coolants, the cleaning process was capable of removing the residue. The variation of the surface and near surface composition of samples machined either dry or with coolants was negligible after cleaning. The use of such coolants in the machining process is therefore recommended

  8. CFD Analysis of in-Cylinder Flow and Air-Fuel Interaction on Different Combustion Chamber Geometry in DISI Engine

    OpenAIRE

    B. Harshavardhan; Mallikarjuna, J. M.

    2013-01-01

    In this investigation, a CFD analysis has been carried out on in-cylinder fluid flows and air-fuel interaction in Direct Injection Spark Ignition (DISI) engine by changing combustion chamber geometry during intake and compression stroke at an engine speed of 1500 rpm for four different types of piston profiles viz., flat piston, flat piston with centre bowl, dome piston with centre bowl and pentroof offset bowl piston. A polyhedral trimmed cell has been taken for meshing of the geometries usi...

  9. Conjugate Heat transfer Analysis of helical fins with airfoil crosssection and its comparison with existing circular fin design for air cooled engines employing constant rectangular cross-section

    OpenAIRE

    Ashwin Shridhar; Asokan Ram Deepak

    2015-01-01

    Air Cooled Engines have been used in a variety of applications, ranging from airplanes to motorbikes and even stationary or portable engines. Since modern automobiles and airplanes use engines delivering more power, they have to be cooled more efficiently due to which a more complex water cooling system is used for cooling engines with large displacements. Hence air cooling is becoming a thing of the past, especially in the aviation sector due to the advent of more efficient gas t...

  10. Indirect air cooling techniques for control rod drives in the high temperature engineering test reactor

    International Nuclear Information System (INIS)

    The high temperature engineering test reactor (HTTR) is the first high-temperature gas-cooled reactor in Japan with reactor outlet gas temperature of 950 deg. C and thermal power of 30 MW. Sixteen pairs of control rods are employed for controlling the reactivity change of the HTTR. Each standpipe for a pair of the control rods, which is placed on the top head dome of the reactor pressure vessel, contains one control rod drive mechanism. The control rod drive mechanism may malfunction because of reduction of the electrical insulation of the electromagnetic clutch when the temperature exceeds 180 deg. C. Because 31 standpipes stand close together in the standpipe room, 16 standpipes for the control rods, which are located at the center, should be cooled effectively. Therefore, the control rod drives are cooled indirectly by forced air circulation through a pair of ring-ducts with proper air outlet nozzles and inlets. Based on analytical results, a pair of the ring-ducts was installed as one of structures in the standpipe room. Evaluation results through the rise-to-power test of the HTTR showed that temperatures of the electromagnetic clutch and the ambient helium gas inside the control rod standpipe should be below the limits of 180 and 75 deg. C, respectively, at full power operation and at the scram from the operation.

  11. Gas Engine-Driven Heat Pump Chiller for Air-Conditioning and Hot Water Supply Systems

    Science.gov (United States)

    Fujita, Toshihiko; Mita, Nobuhiro; Moriyama, Tadashi; Hoshino, Norimasa; Kimura, Yoshihisa

    In Part 1 of this study, the performance characteristics of a 457kW gas engine-driven heat pump (GHP) chiller have been obtained from a simulation model analysis for both cooling and heating modes and it has been found that the part-load characteristics of the GHP chiller are fairly well. On the back of Part 1, a computer simulation program has been developed for the evaluation of GHP chiller systems to compare with the other types of heat source systems for air-conditioning and hot water supply applications. The simulation program can be used to estimate annual energy consumption, annual CO2 emission, etc. of the systems with the data of monthly and hourly thermal loads on various buildings, outdoor air conditions, and characteristics of various components comprising the systems. By applying this to some cases of medium-scale hotel, office, shop, and hospital buildings, it has been found that the GHP chiller systems have advantages particularly in the cases of hotels and hospitals where a lot of hot water demand exists. It has also been found that the combination of a GHP chiller and a direct-fired absorption water chiller boiler (hot and chilled water generator) appears promising.

  12. Responses to Small Break Loss of Coolant Accidents for SMART

    International Nuclear Information System (INIS)

    The SMART NSSS adopts the design characteristics of containing most of the primary circuit components, such as the reactor core, main coolant pumps (MCPs), steam generators (SGs), and N2 gas pressurizer (PZR) in a single leak-tight Reactor Pressure Vessel (RPV) with a relatively large ratio of the primary coolant inventory to the core power compared to the conventional loop-type PWR. Due to these design characteristics, the SMART can fundamentally eliminate the possibility of Large Break Loss of Coolant Accidents (LBLOCAs), improve the natural circulation capability, and assure a sufficient time to mitigate the possibility of core uncover. Also, SMART adopts inherent safety improving features and passive engineered safety systems such as the substantially large negative moderator temperature coefficients, passive residual heat removal system, emergency core cooling system, and a steel-made leak-tight Safeguard Vessel (SV) housing the RPV. This paper presents the results of the safety analyses using a MARS/SMR code for the instantaneous guillotine ruptures of the major pipelines penetrating the RPV. The analysis results, employing conservative initial/boundary conditions and assumptions, show that the safety systems of the SMART basic design adequately remove the core decay heat without causing core uncover for all the cases of the Small Break Loss of Coolant Accidents (SBLOCAs). The sensitivity study results with variable SV conditions show that the reduced SV net free volume can shorten the time for reaching the thermal and mechanical equilibrium condition between the RPV and SV. Under these boundary conditions, the primary system inventory loss can be minimized and the core remains covered for a longer period of time without any makeup of the coolant. (authors)

  13. A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Ronald [Chrysler Group LLC., Auburn Hills, MI (United States)

    2015-05-20

    FCA US LLC (formally known as Chrysler Group LLC, and hereinafter “Chrysler”) was awarded an American Recovery and Reinvestment Act (ARRA) funded project by the Department of Energy (DOE) titled “A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency” (hereinafter “project”). This award was issued after Chrysler submitted a proposal for Funding Opportunity Announcement DE-FOA- 0000079, “Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light-Duty Vehicles (ATP-LD).” Chrysler started work on this project on June 01, 2010 and completed testing activities on August 30, 2014. Overall objectives of this project were; Demonstrate a 25% improvement in combined Federal Test Procedure (FTP) City and Highway fuel economy over a 2009 Chrysler minivan; Accelerate the development of highly efficient engine and powertrain systems for light-duty vehicles, while meeting future emissions standards; and Create and retain jobs in accordance with the American Recovery and Reinvestment Act of 2009

  14. Control room dose analysis for Maanshan PWR plant during design basis loss of coolant accident

    International Nuclear Information System (INIS)

    To address the issue identified in USNRC's Generic Letter 2003-1 that the unfiltered air in-leakage rate through plant's control room during design basis accident may exceed that assumed in the licensing analysis and thus threat the control room habitability, the control room radiation dose analysis of Maanshan PWR plant has to be re-performed to determine the allowable unfiltered air in-leakage rate. The allowable unfiltered air in-leakage rate is to be determined in such a way that the calculated whole body dose in the control room during the most limiting design basis accident must meet the criteria set forth in 10 CFR 50 Appendix A General Design Criteria (GDC) 19. The determined allowable air in-leakage rate is then employed as an acceptable limit to be met by the control room in-leakage test. In this study, the Maanshan plant control room dose analysis model during loss of coolant accident (LOCA) has been established based on USNRC's RADTRAD computer code. Different release and transport paths have been incorporated in this model, including containment leakage, engineered safety feature (ESF) leakage, and control room filtered and un-filtered air in-leakage. The RADTRAD calculation results are compared with Final Safety Analysis Report (FSAR) results to assure that overall consistency is reached. Finally, considering the uncertainties and margin to be maintained between RADTRAD calculation results and GDC-19 dose limits, an allowable unfiltered air in-leakage rate for control room habitability application during LOCA has been well defined. (author)

  15. Health physics aspects of processing EBR-I coolant

    International Nuclear Information System (INIS)

    The sodium-potassium reactor coolant removed from the Experimental Breeder Reactor Number One after a partial reactor core meltdown had been stored at the Idaho National Engineering and Environmental Laboratory for 40 years. The State of Idaho considered this waste the most hazardous waste stored in the state and required its processing. The reactor coolant was processed in three phases. The first phase converted the alkali metal into a liquid sodium-potassium hydroxide. The second phase converted this caustic to a liquid sodium-potassium carbonate. The third phase solidified the sodium-potassium carbonate into a form acceptable for land disposal. Health physics aspects and dose received during each phase of the processing are discussed

  16. US LMFBR coolant system components

    International Nuclear Information System (INIS)

    Development and use of LMFBR coolant system components in the United States has progressed through more than two decades, with both the government and private sectors participating significantly in the support and conduct of the work. The purpose of this paper is to present the major functional requirements that these components are expected to meet, their current status and future direction of development, and recent test results. The components to be discussed are: (1) primary and intermediate system large sodium piping; (2) primary and intermediate system large sodium valves; (3) primary and intermediate main sodium pumps; (4) intermediate heat exchanger (IHX); and (5) sodium-heated steam generators. The major near-term activities associated with the above components are focused primarily on the Fast Flux Test Facility (FFTF), the Clinch River Breeder Reactor Plant (CRBRP), and the anticipated commercial LMFBR's

  17. Impact of Emissions of Marine Diesel Engines to Air Pollution on the Example of the Yugoslav River Shipping

    Directory of Open Access Journals (Sweden)

    Dragan Ljevaja

    2011-09-01

    Full Text Available The subject of this paper is the impact which marine diesel engines have on air pollution. The combustion of fossil fuels for marine diesel engines produces emission of various greenhouse gases; including carbon dioxide (CO2, methane (CH4, nitrous oxide (N2O, carbon monoxide (CO, oxides of nitrogen (NOx, non-methane volatile organic compounds (NMVOCs, and sulphur dioxide (SO2. Gas emission calculation is shown on the example of the Yugoslav river shipping with two methods for calculating harmful emissions of the marine diesel engines. Technologies for reduction of harmful emissions of marine diesel engines and other engines are also presented, as well as the implementation of those technologies, using the example of the Yugoslav river shipping. One of the objectives of this paper is to determine the actual condition of the fleet, as well as the impact it has on air pollution in Serbia, as a country which plans to become a member of the European Union. A measurement on diesel engines of different production date was done with a special device, in order to get the results that represent reality (about harmful emissions in Serbia. Final task of this paper is to collect information in order to reduce harmful emissions of the marine diesel engines, along with preservation of the environment.

  18. Durability of zirconia thermal-barrier ceramic coatings on air-cooled turbine blades in cyclic jet engine operation

    Science.gov (United States)

    Liebert, C. H.; Jacobs, R. E.; Stecura, S.; Morse, C. R.

    1976-01-01

    Thermal barrier ceramic coatings of stabilized zirconia over a bond coat of Ni Cr Al Y were tested for durability on air cooled turbine rotor blades in a research turbojet engine. Zirconia stabilized with either yttria, magnesia, or calcia was investigated. On the basis of durability and processing cost, the yttria stabilized zirconia was considered the best of the three coatings investigated.

  19. Organic coolant in Winnipeg riverbed sediments

    International Nuclear Information System (INIS)

    Between January and May 1977 a prolonged leak of organic coolant occurred from the Whiteshell Nuclear Research Establishment's nuclear reactor, and a minimum of 1450 kg of coolant entered the Winnipeg River and was deposited on the riverbed. The level of radioactivity associated with this coolant was low, contributing less than 0.2 μGy (0.02 mrad) a year to the natural background gamma radiation field from the riverbed. The concentration of coolant in the water samples never exceeded 0.02 mg/L, the lower limit of detection. The mortality of crayfish, held in cages where the riverbed was covered with the largest deposits of coolant, was not significantly different from that in the control cages upstream of the outfall. No evidence of fish kill was found. (author)

  20. Steam as coolant and lubricant in turning of metal matrix composites

    Institute of Scientific and Technical Information of China (English)

    Raviraj SHETTY; Raghuvir PAI; Vasanth KAMATH; Shrikanth S.RAO

    2008-01-01

    Green cutting has become focus of attention in ecological and environmental protection.Steam is cheap.pollution-free and eco-friendly,and then is a good and economical coolant and lubricant.Steam generator and steam feeding system were developed to generate and feed steam.Comparative experiments were carried out in cutting AA6061-15 v0l.%SiC(25 μm particle size),with cubic boron nitride(CBN)insert KB-90 grade under the conditions of compressed air,oil water emulsion,steam as coolant and lubricant,and dry cutting,respectively.The experimental results show that,with steam as coolant and lubricant,gradual reduction in the cutting force,friction coefficient,surface roughness and cutting temperature values were observed.Further,there was reduction in built up edge formation.1t is proved that use of water steam as coolant and lubricant is environmentally friendly.

  1. Design of Small Test Facility for Engineering Safety Feature Air Clean-up System

    International Nuclear Information System (INIS)

    USNRC (United State Nuclear Regulatory Committee) issued Regulatory Guide 1.52, Rev. 3 (RG. 1.52 Rev.3) in 2006, and the major changes of Rev. 3 with respect to Rev.2 are[1]: 1) the test time was reduced from 10 hours to 15 minutes, 2) instead of DOP (Dioctyl Phthalate) , an alternative challenge agent for the In-place aerosol leak tests of the HEPA (high-efficiency particulate air) filters is also viable, and 3) extension of the test period from 18 months to 24 months for the In-place aerosol leak tests. It is clear that the revised guideline can provide benefits for the licensees without degrading safety standards, and Korean nuclear industry initiated a project to accumulate the background information of these changes and examine if similar changes can be taken places in domestic plants since it is believed that the revised guidance can be applicable if sufficient justifications are provided. As a part of these activities manufacturing the small test facility and testing the performance of ESF ACS (Engineering Safety Feature Air Clean-up System) is required. This paper deals with the design principle and actual design methodology. At first the theoretical review on the filtration mechanism was carried out and then the substantial strategy for test facility design was setup. Actual verification for the goodness of test facility design was conducted using CFD (Computational Fluid Dynamic) analysis. These CFD analyses provide the flow field information both the plant ESF ACS and test facility, and these velocity fields are key parameters for the filtration efficiency

  2. Conceptual design and engineering studies of adiabatic compressed air energy storage (CAES) with thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Hobson, M. J.

    1981-11-01

    The objective of this study was to perform a conceptual engineering design and evaluation study and to develop a design for an adiabatic CAES system using water-compensated hard rock caverns for compressed air storage. The conceptual plant design was to feature underground containment for thermal energy storage and water-compensated hard rock caverns for high pressure air storage. Other design constraints included the selection of turbomachinery designs that would require little development and would therefore be available for near-term plant construction and demonstration. The design was to be based upon the DOE/EPRI/PEPCO-funded 231 MW/unit conventional CAES plant design prepared for a site in Maryland. This report summarizes the project, its findings, and the recommendations of the study team; presents the development and optimization of the plant heat cycle and the selection and thermal design of the thermal energy storage system; discusses the selection of turbomachinery and estimated plant performance and operational capability; describes the control system concept; and presents the conceptual design of the adiabatic CAES plant, the cost estimates and economic evaluation, and an assessment of technical and economic feasibility. Particular areas in the plant design requiring further development or investigation are discussed. It is concluded that the adiabatic concept appears to be the most attractive candidate for utility application in the near future. It is operationally viable, economically attractive compared with competing concerns, and will require relatively little development before the construction of a plant can be undertaken. It is estimated that a utility could start the design of a demonstration plant in 2 to 3 years if research regarding TES system design is undertaken in a timely manner. (LCL)

  3. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    Directory of Open Access Journals (Sweden)

    Nureddin Dinler

    2010-01-01

    Full Text Available Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion equations were solved. The k-e turbulence model was employed. The fuel mass fraction transport equation was used for modeling of the combustion. For this purpose a computational fluid dynamics code was developed by using the finite volume method with FORTRAN programming code. The moving mesh was utilized to simulate the piston motion. The developed code simulates four strokes of engine continuously. In the case of laminar flow combustion, Arrhenius type combustion equations were employed. In the case of turbulent flow combustion, eddy break-up model was employed. Results were given for rich, stoichiometric, and lean mixtures in contour graphs. Contour graphs showed that lean mixture (l = 1.1 has longer combustion duration.

  4. The impact of mass flow and masking on the pressure drop of air filter in heavy-duty diesel engine

    Science.gov (United States)

    Hoseeinzadeh, Sepideh; Gorji-Bandpy, Mofid

    2012-04-01

    This paper presents a computational fluid dynamics (CFD) calculation approach to predict and evaluate the impact of the mass-flow inlet on the pressure drop of turbocharger`s air filtfer in heavy-duty diesel engine. The numerical computations were carried out using a commercial CFD program whereas the inlet area of the air filter consisted of several holes connected to a channel. After entering through the channel, the air passes among the holes and enters the air filter. The effect of masking holes and hydraulic diameter is studied and investigated on pressure drop. The results indicate that pressure drop increase with decreasing of hydraulic diameter and masking of the holes has considerable affect on the pressure drop.

  5. The impact of mass flow and masking on the pressure drop of air filter in heavy-duty diesel engine

    Directory of Open Access Journals (Sweden)

    Gorji-Bandpy Mofid

    2012-04-01

    Full Text Available This paper presents a computational fluid dynamics (CFD calculation approach to predict and evaluate the impact of the mass-flow inlet on the pressure drop of turbocharger`s air filtfer in heavy-duty diesel engine. The numerical computations were carried out using a commercial CFD program whereas the inlet area of the air filter consisted of several holes connected to a channel. After entering through the channel, the air passes among the holes and enters the air filter. The effect of masking holes and hydraulic diameter is studied and investigated on pressure drop. The results indicate that pressure drop increase with decreasing of hydraulic diameter and masking of the holes has considerable affect on the pressure drop.

  6. Flow boiling test of GDP replacement coolants

    International Nuclear Information System (INIS)

    The tests were part of the CFC replacement program to identify and test alternate coolants to replace CFC-114 being used in the uranium enrichment plants at Paducah and Portsmouth. The coolants tested, C4F10 and C4F8, were selected based on their compatibility with the uranium hexafluoride process gas and how well the boiling temperature and vapor pressure matched that of CFC-114. However, the heat of vaporization of both coolants is lower than that of CFC-114 requiring larger coolant mass flow than CFC-114 to remove the same amount of heat. The vapor pressure of these coolants is higher than CFC-114 within the cascade operational range, and each coolant can be used as a replacement coolant with some limitation at 3,300 hp operation. The results of the CFC-114/C4F10 mixture tests show boiling heat transfer coefficient degraded to a minimum value with about 25% C4F10 weight mixture in CFC-114 and the degree of degradation is about 20% from that of CFC-114 boiling heat transfer coefficient. This report consists of the final reports from Cudo Technologies, Ltd

  7. Optimal Area Profiles for Ideal Single Nozzle Air-Breathing Pulse Detonation Engines

    Science.gov (United States)

    Paxson, Daniel E.

    2003-01-01

    The effects of cross-sectional area variation on idealized Pulse Detonation Engine performance are examined numerically. A quasi-one-dimensional, reacting, numerical code is used as the kernel of an algorithm that iteratively determines the correct sequencing of inlet air, inlet fuel, detonation initiation, and cycle time to achieve a limit cycle with specified fuel fraction, and volumetric purge fraction. The algorithm is exercised on a tube with a cross sectional area profile containing two degrees of freedom: overall exit-to-inlet area ratio, and the distance along the tube at which continuous transition from inlet to exit area begins. These two parameters are varied over three flight conditions (defined by inlet total temperature, inlet total pressure and ambient static pressure) and the performance is compared to a straight tube. It is shown that compared to straight tubes, increases of 20 to 35 percent in specific impulse and specific thrust are obtained with tubes of relatively modest area change. The iterative algorithm is described, and its limitations are noted and discussed. Optimized results are presented showing performance measurements, wave diagrams, and area profiles. Suggestions for future investigation are also discussed.

  8. Sodium coolant of fast reactors: Experience and problems

    International Nuclear Information System (INIS)

    In present report the following subjects are considered: state of the coolant and sodium systems under normal operating condition as well as under decommissioning, disclosing of sodium circuits and liquidation of its consequences, cleaning from sodium and decontamination under repairing works of equipment and circuits. Cleaning of coolant and sodium systems under normal operating conditions and under accident contamination. Cleaning of the equipment under repairing works and during decommissioning from sodium and products of its interaction with water and air. Treatment of sodium waste, taking into account a possibility of sodium fires. It is shown that the state of coolant, cover gas, surfaces of constructive materials which are in contact with them, cleaning systems, formed during installation operation require development of specific technologies. Developed technologies ensured safety operation of sodium cooled installations as in normal operating conditions so in abnormal situations. R and D activities in this field and experience gained provided a solid base for coping with problems arising during decommissioning. Prospective research problems are emphasized where the future efforts should be concentrated in order to improve characteristics of sodium cooled reactors and to make their decommissioning optimal and safe. (author)

  9. Novel Air Flow Meter for an Automobile Engine Using a Si Sensor with Porous Si Thermal Isolation

    Directory of Open Access Journals (Sweden)

    Androula G. Nassiopoulou

    2012-11-01

    Full Text Available An air flow meter for measuring the intake air of an automobile engine is presented. It is based on a miniaturized silicon thermal mass flow sensor using a thick porous Si (Po-Si layer for local thermal isolation from the Si substrate, on which the sensor active elements are integrated. The sensor is mounted on one side of a printed circuit board (PCB, on the other side of which the readout and control electronics of the meter are mounted. The PCB is fixed on a housing containing a semi-cylindrical flow tube, in the middle of which the sensor is situated. An important advantage of the present air flow meter is that it detects with equal sensitivity both forward and reverse flows. Two prototypes were fabricated, a laboratory prototype for flow calibration using mass flow controllers and a final demonstrator with the housing mounted in an automobile engine inlet tube. The final demonstrator was tested in real life conditions in the engine inlet tube of a truck. It shows an almost linear response in a large flow range between –6,500 kg/h and +6,500 kg/h, which is an order of magnitude larger than the ones usually encountered in an automobile engine.

  10. Novel air flow meter for an automobile engine using a Si sensor with porous Si thermal isolation.

    Science.gov (United States)

    Hourdakis, Emmanouel; Sarafis, Panagiotis; Nassiopoulou, Androula G

    2012-01-01

    An air flow meter for measuring the intake air of an automobile engine is presented. It is based on a miniaturized silicon thermal mass flow sensor using a thick porous Si (Po-Si) layer for local thermal isolation from the Si substrate, on which the sensor active elements are integrated. The sensor is mounted on one side of a printed circuit board (PCB), on the other side of which the readout and control electronics of the meter are mounted. The PCB is fixed on a housing containing a semi-cylindrical flow tube, in the middle of which the sensor is situated. An important advantage of the present air flow meter is that it detects with equal sensitivity both forward and reverse flows. Two prototypes were fabricated, a laboratory prototype for flow calibration using mass flow controllers and a final demonstrator with the housing mounted in an automobile engine inlet tube. The final demonstrator was tested in real life conditions in the engine inlet tube of a truck. It shows an almost linear response in a large flow range between –6,500 kg/h and +6,500 kg/h, which is an order of magnitude larger than the ones usually encountered in an automobile engine. PMID:23202189

  11. Cold Start Emissions of Spark-Ignition Engines at Low Ambient Temperatures as an Air Quality Risk

    Directory of Open Access Journals (Sweden)

    Bielaczyc Piotr

    2014-12-01

    Full Text Available SI engines are highly susceptible to excess emissions when started at low ambient temperatures. This phenomenon has multiple air quality and climate forcing implications. Direct injection petrol engines feature a markedly different fuelling strategy, and so their emissions behaviour is somewhat different from indirect injection petrol engines. The excess emissions of direct injection engines at low ambient temperatures should also differ. Additionally, the direct injection fuel delivery process leads to the formation of PM, and DISI engines should show greater PM emissions at low ambient temperatures. This study reports on laboratory experiments quantifying excess emissions of gaseous and solid pollutants over a legislative driving cycle following cold start at a low ambient temperature for both engine types. Over the legislative cycle for testing at -7°C (the UDC, emissions of HC, CO, NOx and CO2 were higher when tested at -7°C than at 24°C. Massive increases in emissions of HC and CO were observed, together with more modest increases in NOx and CO2 emissions. Results from the entire driving cycle showed excess emissions in both phases (though they were much larger for the UDC. The DISI vehicle showed lower increases in fuel consumption than the port injected vehicles, but greater increases in emission of HC and CO. DISI particle number emissions increased by around 50%; DISI particle mass by over 600%. The observed emissions deteriorations varied somewhat by engine type and from vehicle to vehicle. Excesses were greatest following start-up, but persisted, even after several hundred seconds’ driving. The temperature of the intake air appeared to have a limited but significant effect on emissions after the engine has been running for some time. All vehicles tested here comfortably met the relevant EU limits, providing further evidence that these limits are no longer challenging and need updating.

  12. An Investigation of Valve Lift Effect on Air Flow and Coefficient of Discharge of Four Stroke Engines Based on Experiment

    Directory of Open Access Journals (Sweden)

    Abdul R. Ismail

    2008-01-01

    Full Text Available The coefficient of discharge (CD is defined as the ratio of actual discharge to ideal discharge. In an engine environment, ideal discharge considers an ideal gas and the process to be free from friction, surface tension, etc. Coefficients of discharge are widely used to monitor the flow efficiency through various engine components and are quite useful in improving the performance of these components. The flow through engines it is equally important to have accurate values for coefficients of discharge through the combinations of valves, ports and ducts. In this experiment investigation of air flow and coefficient of discharge are desirable for inflow (reverse flow through the exhaust port using SuperFlow Flowbench. The coefficients of discharge the diesel engines can be quite measured under steady flow conditions for a range of pressures and flows. This paper presents experimental results for air flow and coefficient of discharge investigating the intake and exhaust flow of four stroke direct injection diesel engines. The CD measurements are shown for various pressures, valve lift per diameters (L/D ratio conditions at the intake port pipe to cylinder and cylinder to exhaust port pipe geometries.

  13. Novel Air Flow Meter for an Automobile Engine Using a Si Sensor with Porous Si Thermal Isolation

    OpenAIRE

    Androula G. Nassiopoulou; Panagiotis Sarafis; Emmanouel Hourdakis

    2012-01-01

    An air flow meter for measuring the intake air of an automobile engine is presented. It is based on a miniaturized silicon thermal mass flow sensor using a thick porous Si (Po-Si) layer for local thermal isolation from the Si substrate, on which the sensor active elements are integrated. The sensor is mounted on one side of a printed circuit board (PCB), on the other side of which the readout and control electronics of the meter are mounted. The PCB is fixed on a housing containing a semi-cyl...

  14. Reactor coolant pump seals: improving their performance

    International Nuclear Information System (INIS)

    Large CANDU plants are benefitting from transient-resistant four-year reliable reactor coolant pump seal lifetimes, a direct result of AECL's 20-year comprehensive seal improvement program involving R and D staff, manufacturers, and plant designers and operators. An overview of this program is presented, which covers seal modification design, testing, post-service examination, specialized maintenance and quality control. The relevancy of this technology to Light Water Reactor Coolant Pump Seals is also discussed

  15. Shutting down a reactor when coolant leaks

    International Nuclear Information System (INIS)

    A liquid metal cooled reactor construction is described in which the control rods are hydraulically supported by the coolant flow. Displacement of the reactor core support structure relative to the control rods is indicated by a change in the coolant flow. In the event of the displacement being excessive hydraulic support of the control rods is lost and the control rods are automatically released into the core to effect an immediate shut down. (U.K.)

  16. Coolant mixing in pressurized water reactors

    OpenAIRE

    Grunwald, G. (Guido); Rohde, Ulrich; Höhne, Thomas

    2010-01-01

    For the analysis of boron dilution transients and main steam line break scenarios the modelling of the coolant mixing inside the reactor vessel is important. The reactivity insertion due to overcooling or deboration depends strongly on the coolant temperature and boron concentration. The three-dimensional flow distribution in the downcomer and the lower plenum of PWR's was calculated with a computational fluid dynamics (CFD) code (CFX-4). Calculations were performed for the PWR's of SIEMENS K...

  17. TECHNOLOGIES TO ENHANCE THE OPERATION OF EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE - MANIFOLD DESIGN FOR CONTROLLING ENGINE AIR BALANCE

    Energy Technology Data Exchange (ETDEWEB)

    Gary D. Bourn; Ford A. Phillips; Ralph E. Harris

    2005-12-01

    This document provides results and conclusions for Task 15.0--Detailed Analysis of Air Balance & Conceptual Design of Improved Air Manifolds in the ''Technologies to Enhance the Operation of Existing Natural Gas Compression Infrastructure'' project. SwRI{reg_sign} is conducting this project for DOE in conjunction with Pipeline Research Council International, Gas Machinery Research Council, El Paso Pipeline, Cooper Compression, and Southern Star, under DOE contract number DE-FC26-02NT41646. The objective of Task 15.0 was to investigate the perceived imbalance in airflow between power cylinders in two-stroke integral compressor engines and develop solutions via manifold redesign. The overall project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity.

  18. Computational studies of the laminar burning velocity of a producer gas and air mixture under typical engine conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sridhar, G.; Paul, P.J.; Mukunda, H.S.

    2005-03-15

    This paper discusses computational results concerning the laminar burning velocity of a biomass-derived producer gas and air mixture at pressures and temperatures typical of the unburned mixture in a reciprocating engine. The computations are based on solving conservation equations describing laminar one-dimensional, multicomponent, chemically reacting, and ideal gas mixtures that have been formulated by earlier researchers. Based on a number of calculations at varying initial pressures and temperatures, and equivalence ratios, an expression for estimating the laminar burning velocity with the recycled gas mass fraction has been obtained. Also, the effect of varying amounts of recycled gas on the burning velocity has been determined. These data on laminar burning velocities will be useful in predicting the burn rate in a spark ignition (SI) engine fuelled with a producer gas and air mixture. (Author)

  19. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  20. Support of the launching of motor car air conditioning systems with the coolant CO{sub 2} (R744). Test bench measurements and practical trials; Unterstuetzung der Markteinfuehrung von Pkw-Klimaanlagen mit dem Kaeltemittel CO{sub 2} (R744). Pruefstandsmessungen und Praxistest

    Energy Technology Data Exchange (ETDEWEB)

    Lemke, Nicholas; Mildenberger, Julia [Technische Univ. Braunschweig (Germany); Graz, Martin [Obrist Engineering GmbH, Lustenau (Austria)

    2011-10-15

    In the research project two passenger car air-conditioning systems were analyzed with regard to cooling capacity and efficiency. The results were compared with one another. The first system was a standard air-conditioning unit using R134a as a refrigerant. As a second system a CO{sub 2} (R744) prototype HVAC unit was used. Both units were investigated on one hand installed in a car on a dynamometer by Obrist Engineering GmbH and on the other hand installed in a calorimetric test rig by Technische Universitaet Braunschweig, Institut fuer Thermodynamik. While the tests in the calorimetric test rig showed comparable efficiencies and cooling capacities for both setups, consumption advantages were determined for the R744- air-conditioning unit installed in the vehicle by the company Obrist. With CO{sub 2} (R744) as a refrigerant for mobile air-conditioning systems an environmental friendly solution is available. (orig.)

  1. Soils washing for removal of heavy oil: Naval Air Engineering Center, Lakehurst, NJ

    International Nuclear Information System (INIS)

    With the recognition that large tracts of land are currently unusable as a result of either accidental spills or past industrial practices (such as oil field development), the USEPA Office of Research and Development evaluated soil washing as an alternative remedial technology for heavy oil contaminated soil at a site located on the Naval Air Engineering Center (NAEC), Lakehurst, New Jersey. The researchers used a self-contained, 100-pound-per-hour soil washer. Electrical, pneumatic, and fluid-pumping capabilities were provided by the trailer-mounted system at a remote No. 6 type oil spill site at the Navy base. Chloroform extracts of the contaminated sandy soil recovered a 0.91 gram/milliliter, 950 centistoke viscosity, dark brown, non-PCB oil. By using a surfactant/solvent solution at ambient temperatures, contaminant levels on the soil were reduced from 3.8% (38,000 milligram/kilogram-RCRA hazardous waste designation) to as low as 0.035% (350 milligram/kilogram) oil concentration. Supplemental laboratory evaluations extending the pilot field evaluations showed at elevated temperatures (120F) that residual oil contamination was less than 0.01% (100 milligram/kilogram). This final oil concentration in the treated soil would be defined as clean under the New Jersey Environmental Cleanup and Responsibilities Act (ECRA). A continuous belt press filter was used to recover the oil in a 47% solids cake that could be used as a secondary fuel feed to a waste boiler. The wash water solution was treated and recycled permitting economical operations

  2. A New Family of Nonlinear Observers for SI Engine Air/Fuel Ratio Control

    DEFF Research Database (Denmark)

    Jensen, P. B.; Olsen, M. B.; Poulsen, J.;

    1997-01-01

    The paper treats a newly developed set of nonlinear observers for advanced spark ignition engine control.......The paper treats a newly developed set of nonlinear observers for advanced spark ignition engine control....

  3. Compatibility of structural materials with fusion reactor coolant and breeder fluids

    International Nuclear Information System (INIS)

    Fusion reactors are characterized by a lithium-containing blanket, a heat transfer medium that is integral with the blanket and first wall, and a heat engine that couples to the heat transfer medium. A variety of lithium-containing substances have been identified as potential blanket materials, including molten lithium metal, molten LiF--BeF2, Pb--Li alloys, and solid ceramic compounds such as Li2O. Potential heat transfer media include liquid lithium, liquid sodium, molten nitrates, water, and helium. Each of these coolants and blankets requires a particular set of chemical and mechanical properties with respect to the associated reactor and heat engine structural materials. This paper discusses the materials factors that underlie the selection of workable combinations of blankets and coolants. It also addresses the materials compatibility problems generic to those blanket-coolant combinations currently being considered in reactor design studies

  4. Dynamic heat transfer model for temperature drop analysis and heat exchange system design of the air-powered engine system

    International Nuclear Information System (INIS)

    In the operation process of an air-powered engine (APE) system, temperature drops happening in critical locations can influence the engine's performance negatively, and even lead to the ice blocking problem. To predict temperature drops during the operation, firstly, the thermodynamic model of the APE and a calculation method for equivalent air temperatures at intake and exhaust ports are described. The cooling mechanism of the pressure-reducing process is analyzed. Then a simplified calculation model of the throttling effect for dynamic temperature analysis is proposed. Furthermore, a complete dynamic model of the APE system is established, by considering models mentioned above and models of the pressure tank and the supply pipeline as well. The model's feasibility on the temperature drop analysis is verified by comparing with corresponding experiments. Simulation of a practical APE system is carried out. Under specific parameter settings, temperature drops of critical locations in the system are predicted. On this basis, the supply system of compressed air is modified and a principle structure of the heat exchange system for the APE system is proposed. The analysis results in this paper can provide a theoretical support for the design of the heat exchange system. - Highlights: • A simplified calculation method of throttling effect for dynamic temperature analysis is proved to be effective in a pressure range from 30 MPa to 1 MPa. • A thermodynamic model of the air powered engine(APE) and a calculation method for equivalent air temperatures are proposed. • Prediction method of the temperature drops of critical positions in the APE system are studied. • A principle structure of the heat exchange system for the APE system is proposed

  5. Gas turbine engine adapted for use in combination with an apparatus for separating a portion of oxygen from compressed air

    Science.gov (United States)

    Bland, Robert J.; Horazak, Dennis A.

    2012-03-06

    A gas turbine engine is provided comprising an outer shell, a compressor assembly, at least one combustor assembly, a turbine assembly and duct structure. The outer shell includes a compressor section, a combustor section, an intermediate section and a turbine section. The intermediate section includes at least one first opening and at least one second opening. The compressor assembly is located in the compressor section to define with the compressor section a compressor apparatus to compress air. The at least one combustor assembly is coupled to the combustor section to define with the combustor section a combustor apparatus. The turbine assembly is located in the turbine section to define with the turbine section a turbine apparatus. The duct structure is coupled to the intermediate section to receive at least a portion of the compressed air from the compressor apparatus through the at least one first opening in the intermediate section, pass the compressed air to an apparatus for separating a portion of oxygen from the compressed air to produced vitiated compressed air and return the vitiated compressed air to the intermediate section via the at least one second opening in the intermediate section.

  6. Conjugate Heat transfer Analysis of helical fins with airfoil crosssection and its comparison with existing circular fin design for air cooled engines employing constant rectangular cross-section

    Directory of Open Access Journals (Sweden)

    Ashwin Shridhar

    2015-06-01

    Full Text Available Air Cooled Engines have been used in a variety of applications, ranging from airplanes to motorbikes and even stationary or portable engines. Since modern automobiles and airplanes use engines delivering more power, they have to be cooled more efficiently due to which a more complex water cooling system is used for cooling engines with large displacements. Hence air cooling is becoming a thing of the past, especially in the aviation sector due to the advent of more efficient gas turbine engines. However air cooled internal combustion engines are still being used in a wide variety of two-wheelers ranging from small single cylinder engines to heavy duty liter class V-twins and Inline fours, due to the non-practicalities associated with the installment of a bulky water cooling system in two-wheelers. So one can ascertain that there is a scope for improving the efficiency of air cooled engines even further. The objective of this paper is to analyze currently existing fin design employed in most of the air cooled engines and improve it by changing the cross-section to a streamlined one and also making the fins in a helical orientation as opposed to the regular circular fins employed. Our analysis comprises of a computational fluid dynamics study of both the fin models with identical dimensions and simulated in the same environment using ANSYS FLUENT 15 software and we attempt to compare their performance using the temperature and heat transfer coefficient distribution plots obtained.

  7. More than Just Hot Air: How Hairdryers and Role Models Inspire Girls in Engineering

    Science.gov (United States)

    Kekelis, Linda; Larkin, Molly; Gomes, Lyn

    2014-01-01

    This article describes a reverse-engineering project where female students take a part a hair dryer--giving them an opportunity to see the many different kinds of engineering disciplines involved in making a hairdryer and that they work together. Mechanical Engineer, Lyn Gome, describes her experience leading a group of middle school girls through…

  8. Air toxics evaluation of ABB Combustion Engineering Low-Emission Boiler Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wesnor, J.D. [ABB/Combustion Engineering, Inc., Windsor, CT (United States)

    1993-10-26

    The specific goals of the program are to identify air toxic compounds that might be emmitted from the new boiler with its various Air Pollution Control device for APCD alternatives in levels of regulatory concern. For the compounds thought to be of concern, potential air toxic control methodologies will be suggested and a Test Protocol will be written to be used in the Proof of Concept and full scale tests. The following task was defined: Define Replations and Standards; Identify Air Toxic Pollutants of Interest to Interest to Utility Boilers; Assesment of Air Toxic By-Products; State of the Art Assessment of Toxic By-Product Control Technologies; and Test Protocol Definition.

  9. Clad-coolant chemical interaction

    International Nuclear Information System (INIS)

    This paper provides an overview of the kinetics for zircaloy clad oxidation behaviour in steam and air during reactor accident conditions. The generation of chemical heat from metal/water reaction is considered. Low-temperature oxidation of zircaloy due to water-side corrosion is further described. (authors)

  10. Virtual design and performance prediction of a silencing air cleaner used in an I.C. engine intake system

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper reports results of the authors' studies on the virtual design method used in the development of low noise intake system of I.C. engine. The resulting high pass-by noise at level above the legislative target at full throttle when engine speed was around 5200 r/min necessitated a BEM-aided redesign task, following the typical process of design and development of an intake system. During the initial design, based on the acoustic theory and the requirements (1. The air flux of the redesigned should equal to or exceed the value of the original flux; 2. The filtering area must not be degraded), and considering the constraint of space in the engine compartment, total volume and rough internal dimensions were determined. During the detailed design, the exact internal dimensions of the air cleaner were determined, and an effective method was applied to improve the acoustic performance at low frequency. The predicted sound power of the intake system indicated that the objective of reducing the overall engine noise by minimizing intake system noise was achieved.

  11. Robust Control of the Air to Fuel Ratio in Spark Ignition Engines with Delayed Measurements from a UEGO Sensor

    Directory of Open Access Journals (Sweden)

    Javier Espinoza-Jurado

    2015-01-01

    Full Text Available A precise control of the normalized air to fuel ratio in spark ignition engines is an essential task. To achieve this goal, in this work we take into consideration the time delay measurement presented by the universal exhaust gas oxygen sensor along with uncertainties in the volumetric efficiency. For that purpose, observers are designed by means of a super-twisting sliding mode estimation scheme. Also two control schemes based on a general nonlinear model and a similar nonlinear affine representation for the dynamics of the normalized air to fuel ratio were designed in this work by using the super-twisting sliding mode methodology. Such dynamics depends on the control input, that is, the injected fuel mass flow, its time derivative, and its reciprocal. The two latter terms are estimated by means of a robust sliding mode differentiator. The observers and controllers are designed based on an isothermal mean value engine model. Numeric and hardware in the loop simulations were carried out with such model, where parameters were taken from a real engine. The obtained results show a good output tracking and rejection of disturbances when the engine is closed loop with proposed control methods.

  12. Air

    International Nuclear Information System (INIS)

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  13. Prevention of nitrate formation in aqueous primary coolant circuits of nuclear power plants

    International Nuclear Information System (INIS)

    As nitrogen source for radiation-induced nitrate formation in air-saturated water of primary coolant circuits dissolved ammonia was identified. Since nitrate is supposed to cause corrosion its formation should be prevented. The addition of a small amount of ethanol prevents the nitrate formation for a long period as calculated from kinetic data obtained by pulse radiolysis. (author)

  14. Demonstration of Air-Power-Assist Engine Technology for Clean Combustion and Direct Energy Recovery in Heavy Duty Application

    Energy Technology Data Exchange (ETDEWEB)

    Hyungsuk Kang; Chun Tai

    2010-05-01

    The first phase of the project consists of four months of applied research, starting from September 1, 2005 and was completed by December 31, 2005. During this time, the project team heavily relied on highly detailed numerical modeling techniques to evaluate the feasibility of the APA technology. Specifically, (i) A GT-Power{sup TM}engine simulation model was constructed to predict engine efficiency at various operating conditions. Efficiency was defined based on the second-law thermodynamic availability. (ii) The engine efficiency map generated by the engine simulation was then fed into a simplified vehicle model, which was constructed in the Matlab/Simulink environment, to predict fuel consumption of a refuse truck on a simple collection cycle. (iii) Design and analysis work supporting the concept of retrofitting an existing Sturman Industries Hydraulic Valve Actuation (HVA) system with the modifications that are required to run the HVA system with Air Power Assist functionality. A Matlab/Simulink model was used to calculate the dynamic response of the HVA system. Computer aided design (CAD) was done in Solidworks for mechanical design and hydraulic layout. At the end of Phase I, 11% fuel economy improvement was predicted. During Phase II, the engine simulation group completed the engine mapping work. The air handling group made substantial progress in identifying suppliers and conducting 3D modelling design. Sturman Industries completed design modification of the HVA system, which was reviewed and accepted by Volvo Powertrain. In Phase II, the possibility of 15% fuel economy improvement was shown with new EGR cooler design by reducing EGR cooler outlet temperature with APA engine technology from Air Handling Group. In addition, Vehicle Simulation with APA technology estimated 4 -21% fuel economy improvement over a wide range of driving cycles. During Phase III, the engine experimental setup was initiated at VPTNA, Hagerstown, MD. Air Handling system and HVA

  15. Optimization of diesel engine performances for a hybrid wind-diesel system with compressed air energy storage

    International Nuclear Information System (INIS)

    Electricity supply in remote areas around the world is mostly guaranteed by diesel generators. This relatively inefficient and expensive method is responsible for 1.2 million tons of greenhouse gas (GHG) emission in Canada annually. Some low- and high-penetration wind-diesel hybrid systems (WDS) have been experimented in order to reduce the diesel consumption. We explore the re-engineering of current diesel power plants with the introduction of high-penetration wind systems together with compressed air energy storage (CAES). This is a viable alternative to major the overall percentage of renewable energy and reduce the cost of electricity. In this paper, we present the operative principle of this hybrid system, its economic benefits and advantages and we finally propose a numerical model of each of its components. Moreover, we are demonstrating the energy efficiency of the system, particularly in terms of the increase of the engine performance and the reduction of its fuel consumption illustrated and supported by a village in northern Quebec. -- Highlights: → The Wind-Diesel-Compressed Air Storage System (WDCAS) has a very important commercial potential for remote areas. → The WDCAS is conceived like the adaptation of the existing engines at the level of the intake system. → A wind turbine and an air compression and storage system are added on the diesel plant. → This study demonstrates the potential of WDCAS to reduce fuel consumption and increase the efficiency of the diesel engine. → This study demonstrates that we can expect savings which can reach 50%.

  16. Transient response of turbocharged diesel engine for transient operation using air injection assist system

    OpenAIRE

    Gilkes, Oliver S.; Mishra, Rakesh; John D. Fieldhouse; Rao, H.V.

    2008-01-01

    Great improvements have been made in engine performance and emission control due to recent intensive research on engine systems. Further improvements are still required and turbocharging is aiding further improvements in emissions, power and downsizing. Turbocharged vehicles, however, exhibit a weak point of poor drivability under transient running conditions. This poor drivability has a detrimental affect on the engines emission output during the transient phase. Various methods are be...

  17. Commissioning and Performance Analysis of WhisperGen Stirling Engine

    Science.gov (United States)

    Pradip, Prashant Kaliram

    Stirling engine based cogeneration systems have potential to reduce energy consumption and greenhouse gas emission, due to their high cogeneration efficiency and emission control due to steady external combustion. To date, most studies on this unit have focused on performance based on both experimentation and computer models, and lack experimental data for diversified operating ranges. This thesis starts with the commissioning of a WhisperGen Stirling engine with components and instrumentation to evaluate power and thermal performance of the system. Next, a parametric study on primary engine variables, including air, diesel, and coolant flowrate and temperature were carried out to further understand their effect on engine power and efficiency. Then, this trend was validated with the thermodynamic model developed for the energy analysis of a Stirling cycle. Finally, the energy balance of the Stirling engine was compared without and with heat recovery from the engine block and the combustion chamber exhaust.

  18. A methodology for the evaluation of the turbine jet engine fragment threat to generic air transportable containers

    International Nuclear Information System (INIS)

    Uncontained, high-energy gas turbine engine fragments are a potential threat to air-transportable containers carried aboard jet aircraft. The threat to a generic example container is evaluated by probability analyses and penetration testing to demonstrate the methodology to be used in the evaluation of a specific container/aircraft/engine combination. Fragment/container impact probability is the product of the uncontained fragment release rate and the geometric probability that a container is in the path of this fragment. The probability of a high-energy rotor burst fragment from four generic aircraft engines striking one of the containment vessels aboard a transport aircraft is approximately 1.2 x 10-9 strikes/hour. Finite element penetration analyses and tests can be performed to identify specific fragments which have the potential to penetrate a generic or specific containment vessel. The relatively low probability of engine fragment/container impacts is primarily due to the low release rate of uncontained, hazardous jet engine fragments

  19. Effects of biodiesel on emissions of regulated air pollutants and polycyclic aromatic hydrocarbons under engine durability testing

    International Nuclear Information System (INIS)

    An 80,000-km durability test was performed on two engines using diesel and biodiesel (methyl ester of waste cooking oil) as fuel in order to examine emissions resulting from the use of biodiesel. The test biodiesel (B20) was blended with 80% diesel and 20% methyl ester derived from waste cooking oil. Emissions of regulated air pollutants, including CO, HC, NOx, particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) were measured at 20,000-km intervals. The identical-model engines were installed on a standard dynamometer equipped with a dilution tunnel used to measure the pollutants. To simulate real-world driving conditions, emission measurements were made in accordance with the United States Environmental Protection Agency (USEPA) FTP transient cycle guidelines. At 0 km of the durability test, HC, CO and PM emission levels were lower for the B20 engine than those for diesel. After running for 20,000 km and longer, they were higher. However, the deterioration coefficients for these regulated air pollutants were not statistically higher than 1.0, implying that the emission factors do not increase significantly after 80,000 km of driving. Total (gaseous+particulate phase) PAH emission levels for both B20 and diesel decreased as the driving mileage accumulated. However, for the engine using B20 fuel, particulate PAH emissions increased as engine mileage increased. The average total PAH emission factors were 1097 and 1437 μg bhp h-1 for B20 and diesel, respectively. For B20, the benzo[a]pyrene equivalence emission factors were 0.77, 0.24, 0.20, 7.48, 5.43 and 14.1 μg bhp h-1 for 2-, 3-, 4-, 5-, 6-ringed and total PAHs. Results show that B20 use can reduce both PAH emission and its corresponding carcinogenic potency. (author)

  20. Lead Coolant Test Facility Development Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Paul A. Demkowicz

    2005-06-01

    A workshop was held at the Idaho National Laboratory on May 25, 2005, to discuss the development of a next generation lead or lead-alloy coolant test facility. Attendees included representatives from the Generation IV lead-cooled fast reactor (LFR) program, Advanced Fuel Cycle Initiative, and several universities. Several participants gave presentations on coolant technology, existing experimental facilities for lead and lead-alloy research, the current LFR design concept, and a design by Argonne National Laboratory for an integral heavy liquid metal test facility. Discussions were focused on the critical research and development requirements for deployment of an LFR demonstration test reactor, the experimental scope of the proposed coolant test facility, a review of the Argonne National Laboratory test facility design, and a brief assessment of the necessary path forward and schedule for the initial stages of this development project. This report provides a summary of the presentations and roundtable discussions.

  1. Study on diesel cylinder-head cooling using nanofluid coolant with jet impingement

    OpenAIRE

    Su Zhong-Gen; Zheng Wei; Zhang Zhen-Dong

    2015-01-01

    To improve the heat-transfer performance of a diesel-engine cylinder head, nanofluid coolant as a new fluid was investigated, and jet impingement technology was then used to study on how to better improve heat-transfer coefficient at the nose bridge area in the diesel-engine cylinder head. Computational fluid dynamic simulation and experiments results demonstrated that using the same jet impingement parameters, the different volume shares of nanofluids show...

  2. Secondary coolant purification system with demineralizer bypass

    International Nuclear Information System (INIS)

    Apparatus and method are provided for a nuclear stream supply system for adequately controlling the chemistry of the secondary coolant. The invention includes means for the addition of volatile chemicals, a full flow condensate demineralizer, continuous blowdown capability, radiation detection means, a condensate demineralizer bypass line, and an auxiliary demineralizer bypass line, and an auxiliary demineralizer sized to handle full blowdown flow. The auxiliary demineralizer is cut into the system and the steam generator feedwater flow is bypassed around the full flow condensate demineralizer whenever radioactivity is detected in the secondary coolant

  3. On-Line Coolant Chemistry Analysis

    Energy Technology Data Exchange (ETDEWEB)

    LM Bachman

    2006-07-19

    Impurities in the gas coolant of the space nuclear power plant (SNPP) can provide valuable indications of problems in the reactor and an overall view of system health. By monitoring the types and amounts of these impurities, much can be implied regarding the status of the reactor plant. However, a preliminary understanding of the expected impurities is important before evaluating prospective detection and monitoring systems. Currently, a spectroscopy system is judged to hold the greatest promise for monitoring the impurities of interest in the coolant because it minimizes the number of entry and exit points to the plant and provides the ability to detect impurities down to the 1 ppm level.

  4. On-Line Coolant Chemistry Analysis

    International Nuclear Information System (INIS)

    Impurities in the gas coolant of the space nuclear power plant (SNPP) can provide valuable indications of problems in the reactor and an overall view of system health. By monitoring the types and amounts of these impurities, much can be implied regarding the status of the reactor plant. However, a preliminary understanding of the expected impurities is important before evaluating prospective detection and monitoring systems. Currently, a spectroscopy system is judged to hold the greatest promise for monitoring the impurities of interest in the coolant because it minimizes the number of entry and exit points to the plant and provides the ability to detect impurities down to the 1 ppm level

  5. A fracture mechanics approach for estimating fatigue crack initiation in carbon and low-alloy steels in LWR coolant environments

    International Nuclear Information System (INIS)

    A fracture mechanics approach for elastic-plastic materials has been used to evaluate the effects of light water reactor (LWR) coolant environments on the fatigue lives of carbon and low-alloy steels. The fatigue life of such steel, defined as the number of cycles required to form an engineering-size crack, i.e., 3-mm deep, is considered to be composed of the growth of (a) microstructurally small cracks and (b) mechanically small cracks. The growth of the latter was characterized in terms of ΔJ and crack growth rate (da/dN) data in air and LWR environments; in water, the growth rates from long crack tests had to be decreased to match the rates from fatigue S-N data. The growth of microstructurally small cracks was expressed by a modified Hobson relationship in air and by a slip dissolution/oxidation model in water. The crack length for transition from a microstructurally small crack to a mechanically small crack was based on studies on small crack growth. The estimated fatigue S-N curves show good agreement with the experimental data for these steels in air and water environments. At low strain amplitudes, the predicted lives in water can be significantly lower than the experimental values

  6. Air cargo: An Integrated Systems View. 1978 Summer Faculty Fellowship Program in Engineering Systems Design

    Science.gov (United States)

    Keaton, A. (Editor); Eastman, R. (Editor); Hargrove, A. (Editor); Rabiega, W. (Editor); Olsen, R. (Editor); Soberick, M. (Editor)

    1978-01-01

    The national air cargo system is analyzed and how it should be in 1990 is prescribed in order to operate successfully through 2015; that is through one equipment cycle. Elements of the system which are largely under control of the airlines and the aircraft manufacturers are discussed. The discussion deals with aircraft, networks, facilities, and procedures. The regulations which govern the movement of air freight are considered. The larger public policy interests which must be served by the kind of system proposed, the air cargo integrated system (ACIS), are addressed. The possible social, economical, political, and environment impacts of the system are considered. Recommendations are also given.

  7. Affordable High Power Density Engine Designs for Personal Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Next generation General Aviation (GA) Sport Class air vehicles limited to 1200lbs, represent the first opportunity to overhaul the FAA certification process...

  8. Performance and evaluation of gas-engine-driven split-system cooling equipment at the Willow Grove Naval Air Station

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Schmelzer, J.R.

    1997-01-01

    DOE`s Federal Energy Management Program supports efforts to reduce energy use and associated expenditures within the federal sector; one such effort, the New Technology Demonstration Program (NTDP)(formerly the Test Bed Demonstration program), seeks to evaluate new energy saving US technologies and secure their more timely adoption by the federal government. This report describes the field evaluation conducted to examine the performance of a 15-ton natural-gas-engine- driven, split-system, air-conditioning unit. The unit was installed at a multiple-use building at Willow Grove Naval Air Station, a regular and reserve training facility north of Philadelphia, and its performance was monitored under the NTDP.

  9. Hot air engines: Study of a Stirling engine and of an Ericsson engine; Moteurs thermiques a apport de chaleur externe: etude d'un moteur stirling et d'un moteur ericsson

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, S.

    2005-11-15

    In the current energy context, we attend the development of technologies of production of 'clean' energy. Thus, news prospects like thermodynamic solar energy conversion or waste energy conversion are offered to research on 'renewable energies'. Within this framework, we are interested in hot air engines: Stirling and Ericsson engines. First of all, this thesis concerns the study of a small Stirling engine on which we measured the fluid instantaneous temperature and pressure in various points. The original results obtained are compared to results from two different analyses. We conclude that these models are not suitable to explain the experimental results. Then, we study a micro-cogeneration system based on an Ericsson engine coupled with a system of natural gas combustion. An Ericsson engine is a reciprocating engine working on a JOULE cycle. The objective of this plant is to produce 11 kW of electric output as well as useful heat. In order to design this system, we carried out energetic, exergetic and exergo-economic studies. (author)

  10. Performance and evaluation of gas-engine-driven rooftop air conditioning equipment at the Willow Grove Naval Air Station. Final report (revised October 21, 1996)

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Katipamula, S.

    1996-10-01

    The performance was evaluated of a new US cooling technology that has been installed for the first time at a federal facility. The technology is a 15-ton natural gas-engine-driven rooftop air conditioning unit made by Thermo King. Two units were installed to serve the Navy Exchange at Willow Grove. The savings potential at Willow Grove is described and that in the federal sector estimated. Conditions for implementation are discussed. In summary, the new technology is generally cost-effective at sites where marginal electricity cost (per MBtu at the meter) is more than 4 times the marginal gas cost (per MBtu at the meter) and annual full-load-equivalent cooling hours exceed 2,000.

  11. The conference of Russian Association of Engineers for Heating, Ventilation, Air-Conditioning, Heat Supply and Building Thermal Physics (ABOK

    Directory of Open Access Journals (Sweden)

    V.M. Yakubson

    2014-04-01

    Full Text Available On April, 11th, in Lenexpo the XVI conference of Russian Association of Engineers for Heating, Ventilation, Air-Conditioning, Heat Supply and Building Thermal Physics (ABOK “Effective HVAC and Heat Supply Systems” took place. There were a lot of presentations of new equipment for building systems and networks. All these reports were dedicated to the ways to make buildings more comfortable for people, to increase the energy efficiency, to reduce expenses and to improve the production efficiency. But besides the specific equipment, there were some reports dedicated to more general problems in design, installation and maintenance of building systems and networks

  12. An Integrated Heavy Fuel Piston Engine Ducted Fan Propulsion Unit for Personal Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed PAVE propulsion system technology demonstration combines an innovative high-speed aero-diesel engine with a novel ducted fan assembly resulting in a...

  13. Nonlinear torque and air-to-fuel ratio control of spark ignition engines using neuro-sliding mode techniques.

    Science.gov (United States)

    Huang, Ting; Javaherian, Hossein; Liu, Derong

    2011-06-01

    This paper presents a new approach for the calibration and control of spark ignition engines using a combination of neural networks and sliding mode control technique. Two parallel neural networks are utilized to realize a neuro-sliding mode control (NSLMC) for self-learning control of automotive engines. The equivalent control and the corrective control terms are the outputs of the neural networks. Instead of using error backpropagation algorithm, the network weights of equivalent control are updated using the Levenberg-Marquardt algorithm. Moreover, a new approach is utilized to update the gain of corrective control. Both modifications of the NSLMC are aimed at improving the transient performance and speed of convergence. Using the data from a test vehicle with a V8 engine, we built neural network models for the engine torque (TRQ) and the air-to-fuel ratio (AFR) dynamics and developed NSLMC controllers to achieve tracking control. The goal of TRQ control and AFR control is to track the commanded values under various operating conditions. From simulation studies, the feasibility and efficiency of the approach are illustrated. For both control problems, excellent tracking performance has been achieved. PMID:21656924

  14. Heavy-duty diesel engine NO{sub x} reduction with nitrogen-enriched combustion air. Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, S.; Energy Systems

    2010-07-28

    The concept of engine emissions control by modifying intake combustion gas composition from that of ambient air using gas separation membranes has been developed during several programs undertaken at Argonne. These have led to the current program which is targeted at heavy-duty diesel truck engines. The specific objective is reduction of NO{sub x} emissions by the target engine to meet anticipated 2007 standards while extracting a maximum of 5 percent power loss and allowing implementation within commercial constraints of size, weight, and cost. This report includes a brief review of related past programs, describes work completed to date during the current program, and presents interim conclusions. Following a work schedule adjustment in August 2002 to accommodate problems in module procurement and data analysis, activities are now on schedule and planned work is expected to be completed in September, 2004. Currently, we believe that the stated program requirements for the target engine can be met, based upon extrapolation of the work completed. Planned project work is designed to experimentally confirm these projections and result in a specification for a module package that will meet program objectives.

  15. Mock-up experiment of radiation streaming through coolant pipe penetration

    International Nuclear Information System (INIS)

    The pressure vessel of Mutsu is enclosed by a primary shield consisting of a laminated iron-water shield padded with lead (lower primary shield), atop which is placed concrete shields (middle and upper primary shield). Between the primary shield and the pressure vessel, there is an air gap through which coolant piping of 23.1 cm outside diameter padded with thermal insulation penetrates from the pressure vessel into and through the concrete shield. The radiation from the reactor core streams into the air gap, and then into the coolant pipe. A mock-up experiment to examine the radiation attenuation along the coolant pipe penetration through the pressure vessel wall and concrete shield was performed in the JRR-4 swimming pool reactor. The radiation was measured along the air gap and along the coolant pipe. Neutron measurements were made in terms of the reaction rates of 58Ni(n,p) 58Co and 197Au(n,γ)198Au. Lithium fluoride thermoluminescence dosimeters were also used to obtain neutron flux and gamma-ray dose rates. For analyzing the experimental results, radiation transport calculations were performed by means of the S/sub n/ code TWOTRAN. The annular air gap around the pressure vessel was treated in two dimensions. The resulting angular flux was adapted to calculations covering the coolant pipe, through conversion of coordinates accompanied to bootstrap treatment. Comparisons made between calculated results and experimental data indicated that the preset data and design method are adequate for estimating the radiation leakage with satisfactory accuracy

  16. Exhaust Emission Characteristics of Heavy Duty Diesel Engine During Cold and Warm Start

    Directory of Open Access Journals (Sweden)

    YANG Rong

    2014-07-01

    Full Text Available Through experiment conducted on a six cylinder direct injection diesel engine with SCR catalyst, effects of coolant temperature on rail pressure, injection quantity, excess air coefficient and emissions characteristics during cold and warm start were investigated. The results showed that, the maximum injection quantity during a starting event was several times higher than idling operation mode, so was the maximal opacity in the cold and warm starting process. When coolant temperature rose up to above 20℃, NOX emissions in the starting process exhibited peculiar rise which was times higher than idling mode. Compared with engine warm start, rail pressure, cycle fuel quantity, opacity, CO and HC emissions during engine cold start were higher in the course from their transient maximal values towards stabilized idling status. NOX in the same transient course, however, were lower in cold start. As coolant temperature rose, the maximal and the idling value of rail pressure and cycle fuel injection quantity during diesel engine starting process decreased gradually, the excess air coefficient increased to a certain degree, and the maximal and idling values of NOX increased gradually.

  17. Effect of Air Temperature and Relative Humidity at Various Fuel-Air Ratios on Exhaust Emissions on a Per-Mode Basis of an AVCO Lycoming 0-320 Diad Light Aircraft Engine: Volume 1: Results and Plotted Data

    Science.gov (United States)

    Skorobatckyi, M.; Cosgrove, D. V.; Meng, P. R.; Kempe, E. E., Jr.

    1978-01-01

    A carbureted four cylinder air cooled 0-320 DIAD Lycoming aircraft engine was tested to establish the effects of air temperature and humidity at various fuel-air ratios on the exhaust emissions on a per-mode basis. The test conditions include carburetor lean out at air temperatures of 50, 59, 80, and 100 F at relative humidities of 0, 30, 60, and 80 percent. Temperature humidity effects at the higher values of air temperature and relative humidity tested indicated that the HC and CO emissions increased significantly, while the NOx emissions decreased. Even at a fixed fuel air ratio, the HC emissions increase and the NOx emissions decrease at the higher values of air temperature and humidity.

  18. Effect of air temperature and relative humidity at various fuel-air ratios on exhaust emissions on a per-mode basis of an Avco Lycoming 0-320 DIAD light aircraft engine. Volume 2: Individual data points

    Science.gov (United States)

    Skorobatckyi, M.; Cosgrove, D. V.; Meng, P. R.; Kempke, E. R.

    1976-01-01

    A carbureted four cylinder air cooled 0-320 DIAD Lycoming aircraft engine was tested to establish the effects of air temperature and humidity at various fuel-air ratios on the exhaust emissions on a per-mode basis. The test conditions included carburetor lean-out at air temperatures of 50, 59, 80, and 100 F at relative humidities of 0, 30, 60, and 80 percent. Temperature-humidity effects at the higher values of air temperature and relative humidity tested indicated that the HC and CO emissions increased significantly, while the NOx emissions decreased. Even at a fixed fuel-air ratio, the HC emissions increase and the NOx emissions decrease at the higher values of air temperature and humidity. Volume II contains the data taken at each of the individual test points.

  19. Performance evaluation of an advanced air-fuel ratio controller on a stationary, rich-burn natural gas engine

    Science.gov (United States)

    Kochuparampil, Roshan Joseph

    The advent of an era of abundant natural gas is making it an increasingly economical fuel source against incumbents such as crude oil and coal, in end-use sectors such as power generation, transportation and industrial chemical production, while also offering significant environmental benefits over these incumbents. Equipment manufacturers, in turn, are responding to widespread demand for power plants optimized for operation with natural gas. In several applications such as distributed power generation, gas transmission, and water pumping, stationary, spark-ignited, natural gas fueled internal combustion engines (ICEs) are the power plant of choice (over turbines) owing to their lower equipment and operational costs, higher thermal efficiencies across a wide load range, and the flexibility afforded to end-users when building fine-resolution horsepower topologies: modular size increments ranging from 100 kW -- 2 MW per ICE power plant compared to 2 -- 5 MW per turbine power plant. Under the U.S. Environment Protection Agency's (EPA) New Source Performance Standards (NSPS) and Reciprocating Internal Combustion Engine National Emission Standards for Hazardous Air Pollutants (RICE NESHAP) air quality regulations, these natural gas power plants are required to comply with stringent emission limits, with several states mandating even stricter emissions norms. In the case of rich-burn or stoichiometric natural gas ICEs, very high levels of sustained emissions reduction can be achieved through exhaust after-treatment that utilizes Non Selective Catalyst Reduction (NSCR) systems. The primary operational constraint with these systems is the tight air-fuel ratio (AFR) window of operation that needs to be maintained if the NSCR system is to achieve simultaneous reduction of carbon monoxide (CO), nitrogen oxides (NOx), total hydrocarbons (THC), volatile organic compounds (VOCs), and formaldehyde (CH 2O). Most commercially available AFR controllers utilizing lambda (oxygen

  20. Fuel-coolant chemical interaction

    International Nuclear Information System (INIS)

    A thermodynamic analysis of the uranium-oxygen system is used to determine the equilibrium state of oxidised fuel as a function of the atmospheric oxygen potential (i.e., hydrogen-to-steam partial pressure ratio) as required for the development of fuel-oxidation kinetics models. Annealing experiments have been performed to investigate the oxidation kinetics of fuel in a steam atmosphere at high temperature as well as the fuel-reduction kinetics. Mathematical treatments of these phenomena, coupled with heat and mass transport theory, can be used to describe the oxidation behaviour of uranium dioxide fuel in operating defective rods for water-cooled nuclear reactors. Model predictions are consistent with the observed oxygen-to-metal ratios seen in commercial defective rods as measured post-test using a coulometric titration technique. Such models can be further extended to higher temperature using a phase-field approach to simulate centreline melting in defective fuel. Fuel oxidation effects in air and water at low temperature are also discussed. (authors)

  1. NGNP Reactor Coolant Chemistry Control Study

    Energy Technology Data Exchange (ETDEWEB)

    Brian Castle

    2010-11-01

    The main focus of this paper is to identify the most desirable ranges of impurity levels in the primary coolant to optimize component life in the primary circuit of the Next Generation Nuclear Plant (NGNP), which will either be a prismatic block or pebble bed reactor.

  2. Proposal for evaluation methods of reactor outlet coolant temperature in HTGRs

    International Nuclear Information System (INIS)

    The High Temperature engineering Test Reactor (HTTR) is a graphite moderated and gas cooled reactor with the thermal power of 30 MW and the reactor outlet coolant temperature of 850degC/950degC. Rise-to-power test in the HTTR was performed from March 31th to May 1st in 2004 as phase 5 test up to 30 MW in the high temperature test operation mode. It was confirmed that the thermal reactor power and the reactor outlet coolant temperature reached to 30 MW and 950degC respectively on April 19th. Achievement of the reactor outlet coolant temperature of 950degC outside of the reactor pressure vessel is the first time in Japan as well as the world. It means to extend the HTGR use to various heat utilizations such as highly effective power generation with a high-temperature gas turbine and hydrogen production from water with a high-temperature. This report describes proposal for evaluation methods of reactor outlet coolant temperature in the HTGRs through the HTTR operation experiments. The equation is derived from relationships among PRM reading values, reactor outlet coolant temperature, reactor thermal power and heat removal by VCS. The deliberation processes in this study will be applicable to the research and developments of HTGRs in the future. (author)

  3. Storage of HLW in engineered structures: air-cooled and water-cooled concepts

    International Nuclear Information System (INIS)

    A comparative study on an air-cooled and a water-cooled intermediate storage of vitrified, highly radioactive waste (HLW) in overground installations has been performed by Nukem and Belgonucleaire respectively. In the air-cooled storage concept the decay heat from the storage area will be removed using natural convection. In the water-cooled storage concept the decay heat is carried off by a primary and secondary forced-cooling system with redundant and diverse devices. The safety study carried out by Nukem used a fault tree method. It shows that the reliability of the designed water-cooled system is very high and comparable to the inherent, safe, air-cooled system. The impact for both concepts on the environment is determined by the release route, but even during accident conditions the release is far below permissible limits. The economic analysis carried out by Belgonucleaire shows that the construction costs for both systems do not differ very much, but the operation and maintenance costs for the water-cooled facility are higher than for the air cooled facility. The result of the safety and economic analysis and the discussions with the members of the working group have shown some possible significant modifications for both systems, which are included in this report. The whole study has been carried out using certain national criteria which, in certain Member States at least, would lead to a higher standard of safety than can be justified on any social, political or economic grounds

  4. 78 FR 56622 - Airworthiness Directives; Continental Motors, Inc. Reciprocating Engines With Superior Air Parts...

    Science.gov (United States)

    2013-09-13

    ... in AD 2009-16-03 (74 FR 38896, August 5, 2009), to include the CMI 470 series reciprocating engines...-16-03, Amendment 39-15986 (74 FR 38896, August 5, 2009), for certain Teledyne Continental Motors... (74 FR 38896, August 5, 2009), we became aware of supplemental type certificates (STCs) that...

  5. Under actuated air path control of diesel engines for low emissions and high efficiency

    NARCIS (Netherlands)

    Criens, C.; Willems, F.P.T.; Steinbuch, M.

    2013-01-01

    This paper presents a new method for feedback control using the Exhaust Gas Recirculation (EGR) valve and Variable Geometry Turbine (VGT) of a diesel engine. The controller effectively counteracts disturbances in NOx and PM emissions while maintaining the fuel efficiency. It is shown that by using a

  6. Rapid fabrication of poly(DL-lactide) nanofiber scaffolds with tunable degradation for tissue engineering applications by air-brushing.

    Science.gov (United States)

    Behrens, Adam M; Kim, Jeffrey; Hotaling, Nathan; Seppala, Jonathan E; Kofinas, Peter; Tutak, Wojtek

    2016-01-01

    Polymer nanofiber based materials have been widely investigated for use as tissue engineering scaffolds. While promising, these materials are typically fabricated through techniques that require significant time or cost. Here we report a rapid and cost effective air-brushing method for fabricating nanofiber scaffolds using a simple handheld apparatus, compressed air, and a polymer solution. Air-brushing also facilities control over the scaffold degradation rate without adversely impacting architecture. This was accomplished through a one step blending process of high (M w  ≈  100 000 g mol(-1)) and low (M w  ≈  25 000 g mol(-1)) molecular weight poly(DL-lactide) (PDLLA) polymers at various ratios (100:0, 70:30 and 50:50). Through this approach, we were able to control fiber scaffold degradation rate while maintaining similar fiber morphology, scaffold porosity, and bulk mechanical properties across all of the tested compositions. The impact of altered degradation rates was biologically evaluated in human bone marrow stromal cell (hBMSC) cultures for up to 16 days and demonstrated degradation rate dependence of both total DNA concentration and gene regulation. PMID:27121660

  7. Rapid fabrication of poly(DL-lactide) nanofiber scaffolds with tunable degradation for tissue engineering applications by air-brushing

    Science.gov (United States)

    Behrens, Adam M; Kim, Jeffrey; Hotaling, Nathan; Seppala, Jonathan E; Kofinas, Peter; Tutak, Wojtek

    2016-01-01

    Polymer nanofiber based materials have been widely investigated for use as tissue engineering scaffolds. While promising, these materials are typically fabricated through techniques that require significant time or cost. Here we report a rapid and cost effective air-brushing method for fabricating nanofiber scaffolds using a simple handheld apparatus, compressed air, and a polymer solution. Air-brushing also facilities control over the scaffold degradation rate without adversely impacting architecture. This was accomplished through a one step blending process of high (Mw ≈ 100 000 g mol−1) and low (Mw ≈ 25 000 g mol−1) molecular weight poly(DL-lactide) (PDLLA) polymers at various ratios (100:0, 70:30 and 50:50). Through this approach, we were able to control fiber scaffold degradation rate while maintaining similar fiber morphology, scaffold porosity, and bulk mechanical properties across all of the tested compositions. The impact of altered degradation rates was biologically evaluated in human bone marrow stromal cell (hBMSC) cultures for up to 16 days and demonstrated degradation rate dependence of both total DNA concentration and gene regulation. PMID:27121660

  8. Effect of flooding of annulus space between CT and PT with light water coolant and heavy water moderator on AHWR reactor physics parameters

    International Nuclear Information System (INIS)

    In AHWR lattice, the pressure tube (PT) contains light water coolant which carries away heat generated in the fuel pins. The pressure tube (PT) and calandria tube (CT) are separated by air (density=0.0014 g/cc) of wall thickness 1.79 cm. Air between pressure tube and calandria tube acts as insulator and minimize the heat transfer from coolant to moderator which is outside the calandria tube. In case of flooding or under any unforeseeable circumstances, the air gap between the coolant tube and calandria tube may be filled with the light water coolant or heavy water moderator. This paper gives the details of effect of filling the annulus space between CT and PT with light water or heavy water moderator on reactor physics parameters. (author)

  9. Failure probability of PWR reactor coolant loop piping

    International Nuclear Information System (INIS)

    This paper describes the results of assessments performed on the PWR coolant loop piping of Westinghouse and Combustion Engineering plants. For direct double-ended guillotine break (DEGB), consideration was given to crack existence probability, initial crack size distribution, hydrostatic proof test, preservice inspection, leak detection probability, crack growth characteristics, and failure criteria based on the net section stress failure and tearing modulus stability concept. For indirect DEGB, fragilities of major component supports were estimated. The system level fragility was then calculated based on the Boolean expression involving these fragilities. Indirect DEGB due to seismic effects was calculated by convolving the system level fragility and the seismic hazard curve. The results indicate that the probability of occurrence of both direct and indirect DEGB is extremely small, thus, postulation of DEGB in design should be eliminated and replaced by more realistic criteria

  10. Air oxidation behavior of fuel for the high temperature engineering test reactor (HTTR)

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Hironobu; Hayashi, Kimio; Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

    1992-08-01

    The oxidation behavior of the HTTR fuel was studied with respect to the scenario of an air ingress accident which had been assessed in the HTTR safety analysis. The coated fuel particles were heated under a sufficient air flow in the temperature range of 900-1400degC for maximum duration of 600 h (at 1300degC). Failure fractions of the SiC coating layer after the heat treatments remained within the fraction at the fuel production. And the failure behavior of the SiC layer did not depend on such heating conditions as the temperature and the duration in the present experiment. It was confirmed by scanning electron microscopy (SEM), X-ray diffraction and laser Raman spectroscopy that a thin oxide film was formed on the SiC layer by the heat treatments. (author).

  11. Air oxidation behavior of fuel for the high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    The oxidation behavior of the HTTR fuel was studied with respect to the scenario of an air ingress accident which had been assessed in the HTTR safety analysis. The coated fuel particles were heated under a sufficient air flow in the temperature range of 900-1400degC for maximum duration of 600 h (at 1300degC). Failure fractions of the SiC coating layer after the heat treatments remained within the fraction at the fuel production. And the failure behavior of the SiC layer did not depend on such heating conditions as the temperature and the duration in the present experiment. It was confirmed by scanning electron microscopy (SEM), X-ray diffraction and laser Raman spectroscopy that a thin oxide film was formed on the SiC layer by the heat treatments. (author)

  12. Usage of liquid metals in nuclear, thermonuclear engineering and other innovative technologies

    International Nuclear Information System (INIS)

    The physicochemical properties of liquid metal coolants (alkali metals, lead, bismuth and their eutectics) are described. These coolants are used in various nuclear power facilities, including that for submarines and spaceships. It is pointed out that lithium and its alloy with lead are perspective for using in thermonuclear power engineering where they may be not only coolants but also may be tritium breeding media. The practical experience of liquid metal coolants use in nuclear, thermonuclear power engineering and innovation technologies is under consideration

  13. Thermohydraulic al analysis of the loss of coolant accident at research reactor of Atomic Energy Organization of Iran

    International Nuclear Information System (INIS)

    Hydraulic analyzing of loss of coolant in Tehran University Research Reactor is considered. The water around the reactor core is for biological and thermal shielding. Whenever any accident causing the discharge of water of the pool occurred, the reactor core is exposed to air and the temperature of fuel rods raised due to residual heat; therefore, there is the possibility of melting fuel rods and releasing radioactive materials in air. Evaluating the safety of this research reactor, the failure of coolant system was analyzed. The most probability of occurring the accident of loss of coolant and exposing core to air is related to the rupture of output pipelines at the junction to pool. The failure probability was estimated 2.295*10-6 (fault/year). Then, the maximum inflation of fuel, the maximum fission product I131, at reactor core (1.21*10+5), thermal stress, the possibility of releasing radioactive gases from fuel, radiation effect on mechanical properties of fuel and maximum corrosion of fuel can is investigated. Calculation and investigations show that the probability of releasing radioactive materials due to loss of coolant is 1.974*10-8 (fault/year) which is according to international standards on base of Farmer diagram, acceptable. In the loss of coolant accident, time of discharging the water of pool depends on pump function and the situation of fracture. As less as the time of discharge fuel temperature will raise more. The time of discharging water is calculated

  14. Combustion Velocity of Benzine-Benzol-Air Mixtures in High-Speed Internal-Combustion Engines

    Science.gov (United States)

    Schnauffer, Kurt

    1932-01-01

    The present paper describes a device whereby rapid flame movement within an internal-combustion engine cylinder may be recorded and determined. By the aid of a simple cylindrical contact and an oscillograph the rate of combustion within the cylinder of an airplane engine during its normal operation may be measured for gas intake velocities of from 30 to 35 m/s and for velocities within the cylinder of from 20 to 25 m/s. With it the influence of mixture ratios, of turbulence, of compression ratio and kind of fuel on combustion velocity may be determined. Besides the determination of the influence of the above factors on combustion velocity, the degree of turbulence may also be determined. As a unit of reference in estimating the degree of turbulence, the intake velocity of the charge is chosen.

  15. Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station. Interim report, 1992 cooling season

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Conover, D.R.

    1993-05-01

    In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

  16. Laser air-jet engine: the action of shock waves at low laser pulse repetition rates

    International Nuclear Information System (INIS)

    The impact and thermal action of laser sparks on the reflector of a laser engine in which the propulsion is produced by repetitively pulsed radiation is estimated. It is shown that for a low pulse repetition rate, the thermal contact of a plasma with the reflector and strong dynamic resonance loads are inevitable. These difficulties can be surmounted by using the method based on the merging of shock waves at a high pulse repetition rate. (laser applications)

  17. Improving CANDU safety with organic coolant

    International Nuclear Information System (INIS)

    The AECL study of an organic-cooled CANDU reactor was terminated in 1973 when the capital cost advantage of about 10 to 15% and the operational advantage of low primary circuit activity were judged as being insufficient to warrant the diversion of effort from the commercially successful PHWR program. However the OCR has certain safety advantages that take on more significance now than in 1973. The main characteristics of organic coolant that lead to safety advantages are the absence of an exothermic chemical reaction with zirconium, the compatibility with high conductivity uranium carbide fuel and the low vapour pressure. These characteristics lead to considerable simplifications in the safety systems and in the safety analysis. For example, a change to organic coolant could remove the need for emergency core cooling, shutdown cooling and crash cooldown in order to protect the public from the release of fission products (Author) 6 refs., fig

  18. CAREM-25: considerations about primary coolant chemistry

    International Nuclear Information System (INIS)

    World operating experience, in conjunction with basic studies has been modifying chemistry specifications for the primary coolant of water cooled nuclear reactors along with the reactor type and structural materials involved in the design. For the reactor CAREM-25, the following sources of information have been used: 1) Experience gained by the Chemistry Department of the National Atomic Energy Commission (CNEA, Argentina); 2) Participation of the Chemistry Department (CNEA) in international cooperation projects; 3) Guidelines given by EPRI, Siemens-KWU, AECL, etc. Given the main objectives: materials integrity, low radiation levels and personnel safety, which are in turn a balance between the lowest corrosion and activity transport achievable and considering that the CAREM-25 is a pressurized vessel integrated reactor, a group of guidelines for the chemistry and additives for the primary coolant have been given in the present work. (author)

  19. Recovery studies for plutonium machining oil coolant

    Energy Technology Data Exchange (ETDEWEB)

    Navratil, J. D.; Baldwin, C. E.

    1977-04-27

    Lathe coolant oil, contaminated with plutonium and having a carbon tetrachloride diluent, is generated in plutonium machining areas at Rocky Flats. A research program was initiated to determine the nature of plutonium in this mixture of oil and carbon tetrachloride. Appropriate methods then could be developed to remove the plutonium and to recycle the oil and carbon tetrachloride. Studies showed that the mixtures of spent oil and carbon tetrachloride contained particulate plutonium and plutonium species that are soluble in water or in oil and carbon tetrachloride. The particulate plutonium was removed by filtration; the nonfilterable plutonium was removed by adsorption on various materials. Laboratory-scale tests indicated the lathe-coolant oil mixture could be separated by distilling the carbon tetrachloride to yield recyclable products.

  20. MICROSTRUCTURAL CHARACTERIZATION OF PRIMARY COOLANT PIPE STEEL

    OpenAIRE

    Miller, M; Bentley, J.

    1986-01-01

    Atom probe field-ion microscopy, analytical electron microscopy, and optical microscopy have been used to investigate the changes that occur in the microstructure of cast CF 8 primary coolant pipe stainless steel long term thermal aging. The cast duplex microstructure consisted of austenite with 15% δ-ferrite. Investigation of the aged material revealed that the ferrite spinodally decomposed into a fine scaled network of α and α'. A fine G-phase precipitate was also observed in the ferrite. T...

  1. Analysis of reactor coolant pump trip

    International Nuclear Information System (INIS)

    The trip of one reactor coolant pump accident is simulated with using the IAEA-developed WWER-1000 simulation computer software (IAEA-Code) in this article. The results are compared with the information presented for Bushehr Nuclear Power Plant for the same scenario (analyzed by the code Dynamika-97). The obtained results are compatible with the Bushehr Nuclear Power Plant's given data and show a good overall agreement between them

  2. Enhancing resistance to burnout via coolant chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Tu, J. P.; Dinh, T. N.; Theofanous, T. G. [Univ. of California, Santa Barbara (United States)

    2003-07-01

    Boiling Crisis (BC) on horizontal, upwards-facing copper and steel surfaces under the influence of various coolant chemistries relevant to reactor containment waters is considered. In addition to Boric Acid (BA) and TriSodium Phosphate (TSP), pure De-Ionized Water (DIW) and Tap Water (TW) are included in experiments carried out in the BETA facility. The results are related to a companion paper on the large scale ULPU facility.

  3. Permeability and compression of fibrous porous media generated from dilute suspensions of fiberglass debris during a loss of coolant accident

    International Nuclear Information System (INIS)

    Highlights: • Experimental investigation on fibrous debris buildup was conducted. • Head loss through fibrous media was recorded at different approach velocities. • A head loss model through fibrous media was proposed for high porosity (>0.99). • A compression model of fibrous media was developed. - Abstract: Permeability of fibrous porous media has been studied for decades in various engineering applications, including liquid purifications, air filters, and textiles. In nuclear engineering, fiberglass has been found to be a hazard during a Loss-of-Coolant Accident. The high energy steam jet from a break impinges on surrounding fiberglass insulation materials, producing a large amount of fibrous debris. The fibrous debris is then transported through the reactor containment and reaches the sump strainers. Accumulation of such debris on the surface of the strainers produces a fibrous bed, which is a fibrous porous medium that can undermine reactor core cooling. The present study investigated the buildup of fibrous porous media on two types of perforated plate and the pressure drop through the fibrous porous media without chemical effect. The development of the fibrous bed was visually recorded in order to correlate the pressure drop, the approach velocity, and the thickness of the fibrous porous media. The experimental results were compared to semi-theoretical models and theoretical models proposed by other researchers. Additionally, a compression model was developed to predict the thickness and the local porosity of a fibrous bed as a function of pressure

  4. Minimizing secondary coolant blowdown in HANARO

    International Nuclear Information System (INIS)

    There is about 80m3/h loss of the secondary cooling water by evaporation, windage and blowdown during the operation of HANARO, 30MW research reactor. The evaporation and the windage is necessary loss to maintain the performance of cooling tower, but the blowdown is artificial lose to get rid of the foreign material and to maintain the quality of the secondary cooling water. Therefore, minimizing the blowdown loss was studied. It was confirmed, through the relation of the number of cycle and the loss rate of secondary coolant, that the number of cycle is saturated to 12 without blowdown because of the windage loss. When the secondary coolant is treated by high Ca-hardness treatment program (the number of cycle > 10) to maintain the number of cycle around 12 without blowdown, only the turbidity exceeds the limit. By adding filtering system it was confirmed, through the relation of turbidity and filtering rate of secondary cooling water, that the turbidity is reduced below the limit (5 deg.) by 2% of filtering rate without blowdown. And it was verified, through the performance test of back-flow filtering unit, that this unit gets rid of foreign material up to 95% of the back-flow and that the water can be reused as coolant. Therefore, the secondary cooling water can be treated by the high Ca-hardness program and filter system without blowdown

  5. CANDU with supercritical water coolant: conceptual design features

    International Nuclear Information System (INIS)

    An advanced CANDU reactor, with supercritical water as coolant, has many attractive design features. The pressure exceeds 22 MPa but coolant temperatures in excess of 370 degrees C can be reached without encountering the two-phase region with its associated fuel-dry-out and flow-instability problems. Increased coolant temperature leads to increased plant thermodynamic efficiency reducing unit energy cost through reduced specific capital cost and reduced fueling cost. Increased coolant temperature leads to reduced void reactivity via reduced coolant in-core density. Light water becomes a coolant option. To preserve neutron economy, an advanced fuel channel is needed and is described below. A supercritical-water-cooled CANDU can evolve as fuel capabilities evolve to withstand increasing coolant temperatures. (author)

  6. The QED engine spectrum - Fusion-electric propulsion for air-breathing to interstellar flight

    Science.gov (United States)

    Bussard, Robert W.; Jameson, Lorin W.

    1993-01-01

    A new inertial-electrostatic-fusion direct electric power source can be used to drive a relativistic e-beam to heat propellant. The resulting system is shown to yield specific impulse and thrust/mass ratio 2-3 orders of magnitude larger than from other advanced propulsion concepts. This QED system can be applied to aerospace vehicles from air-breathing to near-interstellar flight. Examples are given for Earth/Mars flight missions, that show transit times of 40 d with 20 percent payload in single-stage vehicles.

  7. Adsorption onto activated carbons in environmental engineering: some trends in water and air treatment processes

    Energy Technology Data Exchange (ETDEWEB)

    Le Cloirec, P. [Ecole des Mines de Nantes, UMR CNRS 6144 GEPEA, 44 (France)

    2005-07-01

    Full text of publication follows: Adsorption is commonly used in environmental protection processes and particularly in water and air treatment systems. Organic pollutants in aqueous or gaseous phases are transferred and adsorbed onto porous materials. Activated carbon (powder, grains) treatment is usually carried out and filters are used to eliminate volatile organic compounds (VOC), odors or micropollutants. The main objectives of this paper are to present examples of classical or new activated carbon processes used in drinking water production, wastewater purification or in air treatment in terms of processes, performances and modeling. - Water treatment: Micropollutants such as pesticides, herbicides... are classically removed by activated carbon granular systems in drinking water treatment plants. In order to get a good water quality and to safe money, the breakthrough time has to be accurately determined. Models with mass balance and transfer equations are proposed. However, some difficulties are found especially for complex solutions to get good agreement between experimental data and calculated values. A statistical approach using neural networks is proposed to simulate breakthrough curves. Examples are presented and compared to deterministic models. In order to intensify processes, a combination of ultrafiltration and activated carbon fiber cloth (ACFC) is presented to remove the large spectra of particles and organic molecules present in water. Systems (UF/ACFC) for surface water and industrial colored wastewater are applied and performances are determined as a function of operating conditions. - Air treatment: Activated carbon grain filters are used to control VOC emissions. Due to an exothermic reaction, an increase of local temperature in the reactor is noted and some fire accidents have been reported. For safety technologies, this temperature has to be previously determined. A model is proposed to simulate the breakthrough curves and temperatures

  8. Exploring new coolants for nuclear breeder reactors

    International Nuclear Information System (INIS)

    Breeder reactors are considered a unique tool for fully exploiting natural nuclear resources. In current Light Water Reactors (LWR), only 0.5% of the primary energy contained in the nuclei removed from a mine is converted into useful heat. The rest remains in the depleted uranium or spent fuel. The need to improve resource-efficiency has stimulated interest in Fast-Reactor-based fuel cycles, which can exploit a much higher fraction of the energy content of mined uranium by burning U-238, mainly after conversion into Pu-239. Thorium fuel cycles also offer several potential advantages over a uranium fuel cycle. The coolant initially selected for most of the FBR programs launched in the 1960s was sodium, which is still considered the best candidate for these reactors. However, Na-cooled FBRs have a positive void reactivity coefficient. Among other factors, this fundamental drawback has resulted in the canceled deployment of these reactors. Therefore, it seems reasonable to explore new options for breeder coolants. In this paper, a proposal is presented for a new molten salt (F2Be) coolant that could overcome the safety issues related to the positive void reactivity coefficient of molten metal coolants. Although it is a very innovative proposal that would require an extensive R and D program, this paper presents the very appealing properties of this salt when using a specific type of fuel that is similar to that of pebble bed reactors. The F2Be concept was studied over a typical MOX composition and extended to a thorium-based cycle. The general analysis took into account the requirements for criticality (opening the option of hybrid subcritical systems); the requirements for breeding; and the safety requirement of having a negative coolant void reactivity coefficient. A design window was found in the definition of a F2Be cooled reactor where the safety requirement was met, unlike for molten metal-cooled reactors, which always have positive void reactivity coefficients

  9. 1997 Idaho National Engineering and Environmental Laboratory (INEEL) National Emission Standard for Hazardous Air Pollutants - Radionuclides. Annual report

    International Nuclear Information System (INIS)

    Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1997. Section 1 of this report provides an overview of the INEEL facilities and a brief description of the radioactive materials and processes at the facilities. Section 2 identifies radioactive air effluent release points and diffuse sources at the INEEL and actual releases during 1997. Section 2 also describes the effluent control systems for each potential release point. Section 3 provides the methodology and EDE calculations for 1997 INEEL radioactive emissions

  10. Numerical simulation of nanosecond pulsed DBD in lean methane–air mixture for typical conditions in internal engines

    International Nuclear Information System (INIS)

    Detailed two-dimensional numerical simulations of a high energy loading nanosecond dc pulse DBD in a lean methane–air mixture were conducted for plasma-assisted combustion by integrating individual models of plasma chemistry, photoionization and energy loading. The DBD streamer propagation process with radical productions was clarified at 10 atm and 600 K as under the condition of actual internal engines at ignition. Energy is loaded to the streamer first by the formation of plasma channel and then ceased due to the self-shielding effect. Because of the inversed electric field in a discharge space during decrease in applied voltage, energy is loaded to the discharge again. It was found that higher energy is loaded to the DBD streamer for larger dielectric constant even at lower applied voltage, and higher number density of oxygen radical is produced at almost the same radical production efficiency. (paper)

  11. Modelling Transient Air-water Flows in Civil and Environmental Engineering

    OpenAIRE

    Kerger, François

    2010-01-01

    The present text, submitted to the University of Liège in fulfillment of the requirements for the degree of “Docteur en Sciences de l’Ingénieur”, aims at improving the understanding and description of air‐water interactions in transient flows. A particular emphasis is set on phenomena relevant in civil and environmental engineering, like rivers, pipes, and hydraulic structures. Theoretical results of this doctoral research may be summarized in two main propositions. First, I show that any...

  12. Improvement of emissions and performance by using of air jet, exhaust gas re-circulation and insulation methods in a direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Jafarmadara S.

    2013-01-01

    Full Text Available This article investigates the improvement of operation characteristics and emissions reduction by means of creating an air-cell inside the piston body, exhaust gases recirculating and insulating combustion chamber in a direct injection diesel engine simultaneously. The engine considered is a caterpillar 3401 which was modeled with an air-cell included as part of the piston geometry. This air-cell demonstrates that air injection in late combustion period can be effective in a significant reduction of Soot emission while cold EGR can be effective in reduction of NOx emission. Also for increasing of performance parameters, combustion chamber with air-cell is insulated. The analyses are carried out at part (75% of full load and full load conditions at the same engine speed 1600 rpm. The obtained results indicate that creating the air-cell has a slight effect on improvement of performance parameters and it has significantly effect on Soot reduction. The air-cell decreases the Soot pollutant as a factor of two at both part and full load conditions. Also, the adding 5% of cold EGR in inlet air decreases NOx by about half and insulating the engine increases the power and IMEP by about 7.7% and 8.5% and decreases the ISFC by about 7.5% at part load and increases power and IMEP by 8.5%, 8.5% and decreases ISFC by 8% at full load condition, respectively. Using this method, it was possible to control emissions formation and increase performance parameters simultaneously. The predicted results for mean in-cylinder pressure and emissions are compared to the corresponding experimental results and show good agreements.

  13. Engineering of air-stable Fe/C/Pd composite nanoparticles for environmental remediation applications

    Science.gov (United States)

    Haham, Hai; Grinblat, Judith; Sougrati, Moulay-Tahar; Stievano, Lorenzo; Margel, Shlomo

    2015-09-01

    The present manuscript presents a convenient method for the synthesis of iron/carbon (Fe/C) nanoparticles (NPs) coated with much smaller Pd NPs for the removal of halogenated organic pollutants. For this purpose, iron oxide/polyvinylpyrrolidone (IO/PVP) NPs were first prepared by the thermal decomposition of ferrocene mixed with PVP at 350 °C under an inert atmosphere. IO,Fe/C and Fe/C NPs coated with graphitic and amorphous carbon layers were then produced by annealing the IO/PVP NPs at 500 and 600 °C, respectively, under an inert atmosphere. The effect of the annealing temperature on the chemical composition, shape, crystallinity, surface area and magnetic properties of the IO/PVP, IO,Fe/C and Fe/C NPs has been elucidated. Air-stable Fe/C/Pd NPs were produced by mixing the precursor palladium acetate with the air-stable Fe/C NPs in ethanol. The obtained Fe/C/Pd NPs demonstrated significantly higher environmental activity than the Fe/C NPs on eosin Y, a model halogenated organic pollutant. The environmental activity of the Fe/C/Pd NPs also increased with their increasing Pd content.

  14. Effects of fuel and air mixing on WOT output in direct injection gasoline engine; Chokufun gasoline kikan ni okeru nenryo to kuki no kongo to shutsuryoku seino

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T.; Iriya, Y.; Naito, K.; Mitsumoto, H.; Iiyama, A. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    The effects of in-cylinder charge motion and the characteristics of the fuel spray and piston crown shape on WOT output in a direct injection gasoline engine are investigated. The fuel and air mixing process in a cylinder is analyzed by computer simulation and LIF method visualization. As a result, the technical factors to achieve enough mixing in a DI gasoline engine equipped with bowl in piston optimized for stratified combustion are clarified. 7 refs., 9 figs., 1 tab.

  15. Tracer-based laser-induced fluorescence measurement technique for quantitative fuel/air-ratio measurements in a hydrogen internal combustion engine.

    Science.gov (United States)

    Blotevogel, Thomas; Hartmann, Matthias; Rottengruber, Hermann; Leipertz, Alfred

    2008-12-10

    A measurement technique for the quantitative investigation of mixture formation processes in hydrogen internal combustion engines (ICEs) has been developed using tracer-based laser-induced fluorescence (TLIF). This technique can be employed to fired and motored engine operation. The quantitative TLIF fuel/air-ratio results have been verified by means of linear Raman scattering measurements. Exemplary results of the simultaneous investigation of mixture formation and combustion obtained at an optical accessible hydrogen ICE are shown. PMID:19079454

  16. New Application of Seawater and Electrolyzed Seawater in Air Pollution Control of Marine Diesel Engine

    Science.gov (United States)

    An, Sukheon; Nishida, Osami

    It is the purpose of this paper to introduce the usage of seawater and its electrolysis for the exhaust emission control in marine diesel engines. First, with using only seawater that is naturally alkaline (pH typically around 8.1), the SO2 and SO3 are absorbed by relatively high solubility compared to other components of exhaust pollutants, and PMs (Particulate Matter) are removed through direct contact with the sprayed seawater droplets. Besides, the electrolyzed alkaline seawater by electrolysis, which contains mainly NaOH together with alkali metal ions (i. e. Na+, Mg2+, Ca2+), is used as the absorption medium of NOx and CO2. Conditionally, before the NOx absorption treatment with using the alkaline seawater, nitric oxide (NO) must be adequately oxidized to nitrogen dioxide (NO2) by the acidic seawater in order to increase NOx absorption rate into the alkaline seawater. Because NOx absorption is the most suited to conditions when both volume fractions (NO: NO2 ratio) are of equal portions. Finally, this research would also plan to treat the effluent by applying electro-dialysis and electro-flotation techniques in the future. The way to reduce emissions from the marine diesel engines is to make it attractive from an operating perspective, as well as an environmental perspective.

  17. In Vitro Deposition of Ca-P Nanoparticles on Air Jet Spinning Nylon 6 Nanofibers Scaffold For Bone Tissue Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Abdal-hay, Abdalla, E-mail: abda_55@jbnu.ac.kr [Dept. of Computer Science, Faculty of Engineering, Universidad de Cuenca, Cuenca 01.01.168 (Ecuador); Dept. of Bionano System Engineering, College of Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Dept. of Engineering Materials and Mechanical Design, Faculty of Engineering, South Valley University, Qena 83523 (Egypt); Oh, Yi Seul [Dept. of Mechanical Design Engineering, Advanced Wind Power System Research Institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Yousef, Ayman; Pant, Hem Raj [Dept. of Bionano System Engineering, College of Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Vanegas, Pablo [Dept. of Computer Science, Faculty of Engineering, Universidad de Cuenca, Cuenca 01.01.168 (Ecuador); Lim, Jae Kyoo, E-mail: jklim@jbnu.ac.kr [Dept. of Mechanical Design Engineering, Advanced Wind Power System Research Institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2014-07-01

    Microporous, non-woven nylon 6 (N6) scaffolds were prepared with an air jet spinning (AJS) approach. In this process, polymer fibers with diameters down to the nanometer range (nanofibers) were formed by subjecting a fluid jet to high pressure air. The effects of the solution conditions on the morphological appearance and average diameter of the as-spun N6 fibers and crystal structure were investigated. The morphological properties of the AJS membrane mats could easily be tailored by adjusting the concentration of the polymer solution. Solutions at high concentrations were necessary to form well-defined fibers without beads. The production rate (viz. solvent evaporation rate) had the greatest effect on the chain structure conformation of N6. The predominant structure phase of the N6 fibers fabricated by AJS was a thermodynamically stable α-form while the electrospinning fibers induced the metastable γ-form. AJS significantly enhanced the mechanical properties of the N6 mat. The bone formation ability of AJS fibers was evaluated by incubating the fibers in biomimetic simulated body fluid for 5 and 10 days at 37 °C. Overall, the new AJS approach developed for membrane structures has great potential for the fabrication of hard and soft tissue engineering scaffolds.

  18. In Vitro Deposition of Ca-P Nanoparticles on Air Jet Spinning Nylon 6 Nanofibers Scaffold For Bone Tissue Engineering

    International Nuclear Information System (INIS)

    Microporous, non-woven nylon 6 (N6) scaffolds were prepared with an air jet spinning (AJS) approach. In this process, polymer fibers with diameters down to the nanometer range (nanofibers) were formed by subjecting a fluid jet to high pressure air. The effects of the solution conditions on the morphological appearance and average diameter of the as-spun N6 fibers and crystal structure were investigated. The morphological properties of the AJS membrane mats could easily be tailored by adjusting the concentration of the polymer solution. Solutions at high concentrations were necessary to form well-defined fibers without beads. The production rate (viz. solvent evaporation rate) had the greatest effect on the chain structure conformation of N6. The predominant structure phase of the N6 fibers fabricated by AJS was a thermodynamically stable α-form while the electrospinning fibers induced the metastable γ-form. AJS significantly enhanced the mechanical properties of the N6 mat. The bone formation ability of AJS fibers was evaluated by incubating the fibers in biomimetic simulated body fluid for 5 and 10 days at 37 °C. Overall, the new AJS approach developed for membrane structures has great potential for the fabrication of hard and soft tissue engineering scaffolds.

  19. Experimental Investigation of Nozzle Effects on Thrust and Inlet Pressure of an Air-breathing Pulse Detonation Engine

    Institute of Scientific and Technical Information of China (English)

    CHEN Wenjuan; FAN Wei; ZHANG Quan; PENG Changxin; YUAN Cheng; YAN Chuanjun

    2012-01-01

    Nozzle effects on thrust and inlet pressure of a multi-cycle air-breathing pulse detonation engine (APDE) are investigated experimentally.An APDE with 68 mm in diameter and 2 050 mm in length is operated using gasoline/air mixture.Straight nozzle,converging nozzle,converging-diverging nozzle and diverging nozzle are tested.The results show that thrust augmentation of converging-diverging nozzle,diverging nozzle or straight nozzle is better than that of converging nozzle on the whole.Thrust augmentation of straight nozzle is worse than those of converging-diverging nozzle and diverging nozzle.Thrust augmentations of diverging nozzle with larger expansion ratio and converging-diverging nozzle with larger throat area range from 20% to 40%on tested frequencies and are bener than those of congeneric other nozzles respectively.Nozzle effects on inlet pressure are also researched.At each frequency it is indicated that filling pressures and average peak pressures of inlet with diverging nozzle and converging-diverging nozzle with large throat cross section area are higher than those with straight nozzle and converging nozzle.Pressures near thrust wall increase in an increase order from without nozzle,with diverging nozzle,straight nozzle and converging-diverging nozzle to converging nozzle.

  20. Characterization of solid debris transported in the coolant during the first two severe fuel damage tests

    International Nuclear Information System (INIS)

    This paper presents the results of the characterization of solid debris collected from the coolant during the Severe Fuel Damage Scoping Test and the Severe Fuel Damage Test 1-1 conducted by EG and G Idaho Inc., at the Idaho National Engineering Laboratory. A variety of analytical techniques were used to characterize the debris samples. Fission product release fractions and particle size distributions were measured, and the probable chemical forms in the debris were identified

  1. Flow distribution due to multiple loop seal venting during a small break loss of coolant accident

    International Nuclear Information System (INIS)

    Calculations of a postulated small break Loss-of-Coolant-Accident (LOCA) have been performed using the NOTRUMP computer code for a typical Combustion Engineering pressurized water reactor (PWR). Evaluation Model initial conditions and assumptions were used in the analysis to examine a 0.1016 m (4.0 in.) equivalent diameter cold leg break. The behavior of the loop seals, and their effects on the overall system hydraulics is discussed

  2. Air and blood fluid dynamics: at the interface between engineering and medicine

    International Nuclear Information System (INIS)

    The flows in the human upper airway and human heart during open heart surgery are considered. Beginning with idealized models of the human upper airway, current methods to extract realistic airway geometries using a novel implementation of optical coherent tomography modality are introduced. Complementary direct numerical simulations are considered that will assist in pre-surgery planning for obstructive sleep apnea. Cardiac air bubbles often arise during open heart surgery. These bubbles are potential emboli that can cause neurological impairment and even death. An experimental programme is outlined that uses acoustic sound to instil bubble surface oscillations that result in bubble breakup. A novel algorithm is introduced that enables a surgical team to obtain real-time in-vivo bubble data to aid cardiac de-airation procedures.

  3. Air and blood fluid dynamics: at the interface between engineering and medicine

    Science.gov (United States)

    Pollard, A.; Secretain, F.; Milne, B.

    2014-08-01

    The flows in the human upper airway and human heart during open heart surgery are considered. Beginning with idealized models of the human upper airway, current methods to extract realistic airway geometries using a novel implementation of optical coherent tomography modality are introduced. Complementary direct numerical simulations are considered that will assist in pre-surgery planning for obstructive sleep apnea. Cardiac air bubbles often arise during open heart surgery. These bubbles are potential emboli that can cause neurological impairment and even death. An experimental programme is outlined that uses acoustic sound to instil bubble surface oscillations that result in bubble breakup. A novel algorithm is introduced that enables a surgical team to obtain real-time in-vivo bubble data to aid cardiac de-airation procedures.

  4. Engineering of air-stable Fe/C/Pd composite nanoparticles for environmental remediation applications

    International Nuclear Information System (INIS)

    The present manuscript presents a convenient method for the synthesis of iron/carbon (Fe/C) nanoparticles (NPs) coated with much smaller Pd NPs for the removal of halogenated organic pollutants. For this purpose, iron oxide/polyvinylpyrrolidone (IO/PVP) NPs were first prepared by the thermal decomposition of ferrocene mixed with PVP at 350 °C under an inert atmosphere. IO,Fe/C and Fe/C NPs coated with graphitic and amorphous carbon layers were then produced by annealing the IO/PVP NPs at 500 and 600 °C, respectively, under an inert atmosphere. The effect of the annealing temperature on the chemical composition, shape, crystallinity, surface area and magnetic properties of the IO/PVP, IO,Fe/C and Fe/C NPs has been elucidated. Air-stable Fe/C/Pd NPs were produced by mixing the precursor palladium acetate with the air-stable Fe/C NPs in ethanol. The obtained Fe/C/Pd NPs demonstrated significantly higher environmental activity than the Fe/C NPs on eosin Y, a model halogenated organic pollutant. The environmental activity of the Fe/C/Pd NPs also increased with their increasing Pd content. - Highlights: • Fe/C NPs were produced by thermal annealing of iron oxide/PVP NPs under Ar atmosphere. • Fe/C NPs were coated with a thin layer of smaller Pd NPs by reduction of a Pd precursor. • The environmental activity of the Fe/C/Pd NPs was demonstrated

  5. Engineering of air-stable Fe/C/Pd composite nanoparticles for environmental remediation applications

    Energy Technology Data Exchange (ETDEWEB)

    Haham, Hai; Grinblat, Judith [Institute of Nanotechnology and Advanced Materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900 (Israel); Sougrati, Moulay-Tahar; Stievano, Lorenzo [Institute Charles Gerhardt (UMR 5253 CNRS), Université Montpellier 2, CC 1502, Place E. Bataillon, 34095 Montpellier, Cedex 5 (France); Margel, Shlomo, E-mail: shlomo.margel@mail.biu.ac.il [Institute of Nanotechnology and Advanced Materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900 (Israel)

    2015-09-01

    The present manuscript presents a convenient method for the synthesis of iron/carbon (Fe/C) nanoparticles (NPs) coated with much smaller Pd NPs for the removal of halogenated organic pollutants. For this purpose, iron oxide/polyvinylpyrrolidone (IO/PVP) NPs were first prepared by the thermal decomposition of ferrocene mixed with PVP at 350 °C under an inert atmosphere. IO,Fe/C and Fe/C NPs coated with graphitic and amorphous carbon layers were then produced by annealing the IO/PVP NPs at 500 and 600 °C, respectively, under an inert atmosphere. The effect of the annealing temperature on the chemical composition, shape, crystallinity, surface area and magnetic properties of the IO/PVP, IO,Fe/C and Fe/C NPs has been elucidated. Air-stable Fe/C/Pd NPs were produced by mixing the precursor palladium acetate with the air-stable Fe/C NPs in ethanol. The obtained Fe/C/Pd NPs demonstrated significantly higher environmental activity than the Fe/C NPs on eosin Y, a model halogenated organic pollutant. The environmental activity of the Fe/C/Pd NPs also increased with their increasing Pd content. - Highlights: • Fe/C NPs were produced by thermal annealing of iron oxide/PVP NPs under Ar atmosphere. • Fe/C NPs were coated with a thin layer of smaller Pd NPs by reduction of a Pd precursor. • The environmental activity of the Fe/C/Pd NPs was demonstrated.

  6. Analysis of reactor coolant pump transient performance in primary coolant system during start-up period

    International Nuclear Information System (INIS)

    Highlights: ► Relationships between pump heads and the parameters of a system are established. ► Relationships between pump torques and the parameters of a system are established. ► The variables are non-dimensionlized in order to design a new system and pump. ► All variables are solved analytically. Pump characteristics are not required. ► Mechanism of reactor coolant pump start-up is mathematically solved and clarified. - Abstract: The reactor coolant pump is “the heart” of a nuclear reactor and the only high-speed revolving equipment in a pressurized water reactor primary cooling loop system. The accurate prediction of flow and pump transient performance, during start-up transients, is a very important factor in the reactor coolant pumps design and the nuclear reactor design. Based on the momentum conservation equation of the primary coolant and the moment balance relation of the reactor coolant pump, the transient pump total head, the acceleration head and the overcoming friction head during a pump start up are derived. The relationship between the above heads and the parameters of the system fluid and pump is established too. Furthermore, the transient torques during a pump start-up are also derived. They include the torques required to accelerate the coolant fluid, to accelerate the pump rotating parts and to overcome friction of coolant fluid in the pipes system. The relation between the above three transient torques and the parameters of the coolant fluid and the pump is respectively established. In addition, the above variables are all non-dimensionlized in order to design a new system. The transient flow rate and pump speed are solved analytically. The detailed information of the centrifugal pump characteristics is not required. The analytical non-dimensional flow rate, the pump speed, heads and torques are all affected by an energy ratio β. The effects of β on the three transient heads and the three transient torques are discussed

  7. Coupled reactor physics and coolant dynamics of heavy liquid metal coolant systems

    International Nuclear Information System (INIS)

    Cooling of advanced nuclear designs with heavy liquid metals such as lead or lead-bismuth eutectic offers the potential for plant simplifications and higher operating efficiencies compared to previously considered liquid metal coolants such as sodium or NaK. Such applications would however also introduce additional safety concerns and design challenges, therefore necessitating a verifiable computational tool for transient design-basis analysis of heavy liquid metal coolant (HLMC) systems. This capability would enable analysts to compare operational and safety characteristics of design alternatives, and to evaluate relative performance advantages with a consistent, deterministic measure

  8. Fuel-coolant interactions: preliminary experiments on the effect of gases dissolved in the 'coolant'

    International Nuclear Information System (INIS)

    A simple apparatus has been used to study fuel-coolant interactions under reasonably well controlled conditions. Preliminary experiments have used water as the 'coolant' and molten tin at 8000C as the 'fuel' and have investigated how the violence of the interaction is affected by dissolving gases (oxygen, nitrogen, carbon dioxide and nitrous oxide) in the water. It was found that saturating the water with carbon dioxide or nitrous oxide completely suppresses the violent interaction. Experiments in which the concentrations of these gases were varied showed that a certain critical concentration was needed; below this concentration the dissolved gas has no significant effect but above it the suppression is

  9. Nuclear fuel assembly with large coolant conducting tube

    International Nuclear Information System (INIS)

    This patent describes a fuel assembly for a nuclear reactor comprising elongated fuel rods each containing a column of nuclear fuel; support means providing support positions for retaining the fuel rods in spaced array including a lower tie plate engaging the lower ends of the fuel rods; a nose piece extending from the lower tie plate and forming a coolant receiving chamber; a large diameter elongated coolant conducting tube extending upward through the assembly and occupying the space of the fuel rods, the coolant conducting tube having an opening at its lower end for receiving coolant and an opening at its upper end for discharging coolant; at least one space axially positioned intermediate between the upper and lower ends of the fuel rods for laterally supporting the fuel rods and the coolant conducting tube; and a mounting member for the large diameter coolant conducting tube. The lower end of the mounting member engaging the lower tie plate and the upper end of the mounting member is secured to the lower end of the coolant conducting tube. The mounting member has a relatively small diameter and is relatively flexible compared to the large diameter coolant conducting tube. In the event of lateral displacement of the upper end of the large diameter coolant conducting tube, excessive lateral forces on the spacer are avoided

  10. Nuclear fuel assembly with large coolant conducting tube

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, H.L.; Dunlap, T.G.; Johnson, E.B.; Matzner, B.

    1987-06-23

    This patent describes a fuel assembly for a nuclear reactor comprising elongated fuel rods each containing a column of nuclear fuel; support means providing support positions for retaining the fuel rods in spaced array including a lower tie plate engaging the lower ends of the fuel rods; a nose piece extending from the lower tie plate and forming a coolant receiving chamber; a large diameter elongated coolant conducting tube extending upward through the assembly and occupying the space of the fuel rods, the coolant conducting tube having an opening at its lower end for receiving coolant and an opening at its upper end for discharging coolant; at least one space axially positioned intermediate between the upper and lower ends of the fuel rods for laterally supporting the fuel rods and the coolant conducting tube; and a mounting member for the large diameter coolant conducting tube. The lower end of the mounting member engaging the lower tie plate and the upper end of the mounting member is secured to the lower end of the coolant conducting tube. The mounting member has a relatively small diameter and is relatively flexible compared to the large diameter coolant conducting tube. In the event of lateral displacement of the upper end of the large diameter coolant conducting tube, excessive lateral forces on the spacer are avoided.

  11. Analysis and Design of a Dish/Stirling System for Solar Electric Generation with a 2.7 kW Air-Cooled Engine

    OpenAIRE

    Beltrán-Chacón R.; Velázquez-Limón N.; Sauceda-Carvajal D.

    2012-01-01

    This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, ...

  12. Mid-section of a can-annular gas turbine engine with an improved rotation of air flow from the compressor to the turbine

    Science.gov (United States)

    Little, David A.; Schilp, Reinhard; Ross, Christopher W.

    2016-03-22

    A midframe portion (313) of a gas turbine engine (310) is presented and includes a compressor section with a last stage blade to orient an air flow (311) at a first angle (372). The midframe portion (313) further includes a turbine section with a first stage blade to receive the air flow (311) oriented at a second angle (374). The midframe portion (313) further includes a manifold (314) to directly couple the air flow (311) from the compressor section to a combustor head (318) upstream of the turbine section. The combustor head (318) introduces an offset angle in the air flow (311) from the first angle (372) to the second angle (374) to discharge the air flow (311) from the combustor head (318) at the second angle (374). While introducing the offset angle, the combustor head (318) at least maintains or augments the first angle (372).

  13. Multirods burst tests under loss-of-coolant conditions

    International Nuclear Information System (INIS)

    In order to know the upper limit of coolant flow area restriction in a fuel assembly under loss-of-coolant accidents in LWRs, burst tests of fuel bundles were performed. Each bundle consisted of 49 rods(7x7 rods), and bursts were conducted in flowing steam. In some cases, 4 rods were replaced by control rods with guide tubes in a bundle. After the burst, the ballooning behavior of each rod and the degree of coolant flow area restriction in the bundle were measured. Ballooning behavior of rods and degree of coolant flow channel restriction in bundles with control rods were not different from those without control rods. The upper limit of coolant flow channel restriction under loss-of-coolant conditions was estimated to be about 80%. (author)

  14. Meeting 2006, outdoor noise directive (OND) noise levels for a diesel engine driven air compressor: A case study in noise reduction

    Science.gov (United States)

    Rowe, David F.

    2005-09-01

    In January 2006, the noise limits for many products in the European Union will drop by 2-3 dBA, as directed by 2000/14/EC ``Noise Emission in the Environment by Equipment Used Outdoors,'' commonly called the ``Outdoor Noise Directive,'' or ``OND.'' Air compressors are among the products addressed by this directive. At Ingersoll-Rand, significant effort has been directed at meeting the challenge of reducing noise on a variety of diesel engine driven air compressor platforms, ranging from 15 to 350 kW diesel engine power ratings. This paper presents a case study of the noise reduction on a 750 cfm (21 m3/min) air compressor operating at 300 psig (21 bar), to meet the 2006 OND noise limit of 100 LwA.

  15. Theoretical and experimental study of flow through turbine cascades with coolant flow injection

    Science.gov (United States)

    Tabakoff, W.; Hamed, A.

    1975-01-01

    An analytical study is presented which deals with the change in the outlet flow conditions from a turbine blade row due to coolant air injection through slots. The analysis applies to small secondary to primary mass flow ratios, taking into consideration the change in boundary layer development resulting from injection. The effects of injection location, injection flow angle and injected air momentum flux are investigated. The results of the present analysis are compared with the values obtained using the mixing theory method and experimental data from cold flow tests in a turbine cascade tunnel.

  16. Requirements of coolants in nuclear reactors

    International Nuclear Information System (INIS)

    This study discussed the purposes and types of coolants in nuclear reactors to generate electricity. The major systems and components associated with nuclear reactors are cooling system. There are two major cooling systems utilized to convert the heat generated in the fuel into electrical power. The primary system transfers the heat from the fuel to the steam generator, where the secondary system begins. The steam formed in the steam generator is transferred by the secondary system to the main turbine generator, where it s converted into electricity after passing through the low pressure turbine. There are various coolants used in nuclear reactors-light water, heavy water and liquid metal. The two major types of water-cooled reactors are pressurized water reactors (PWR) and boiling water reactors (BWR) but pressurized water reactors are more in the world. Also discusses this study the reactors and impact of the major nuclear accidents, in the April 1986 disaster at the Chernobyl nuclear power plant in Ukraine was the product operators, and in the March 2011 at the Fukushima nuclear power plant in Japan was the product of earthquake of magnitude 9.0, the accidents caused the largest uncontrolled radioactive release into the environment.(Author)

  17. Cycle-by-cycle Variations in a Direct Injection Hydrogen Enriched Compressed Natural Gas Engine Employing EGR at Relative Air-Fuel Ratios.

    Directory of Open Access Journals (Sweden)

    Olalekan Wasiu Saheed

    2014-07-01

    Full Text Available Since the pressure development in a combustion chamber is uniquely related to the combustion process, substantial variations in the combustion process on a cycle-by-cycle basis are occurring. To this end, an experimental study of cycle-by-cycle variation in a direct injection spark ignition engine fueled with natural gas-hydrogen blends combined with exhaust gas recirculation at relative air-fuel ratios was conducted. The impacts of relative air-fuel ratios (i.e. λ = 1.0, 1.2, 1.3 and 1.4 which represent stoichiometric, moderately lean, lean and very lean mixtures respectively, hydrogen fractions and EGR rates were studied. The results showed that increasing the relative air-fuel ratio increases the COVIMEP. The behavior is more pronounced at the larger relative air-fuel ratios. More so, for a specified EGR rate; increasing the hydrogen fractions decreases the maximum COVIMEP value just as increasing in EGR rates increases the maximum COVIMEP value. (i.e. When percentage EGR rates is increased from 0% to 17% and 20% respectively. The maximum COVIMEP value increases from 6.25% to 6.56% and 8.30% respectively. Since the introduction of hydrogen gas reduces the cycle-by-cycle combustion variation in engine cylinder; thus it can be concluded that addition of hydrogen into direct injection compressed natural gas engine employing EGR at various relative air-fuel ratios is a viable approach to obtain an improved combustion quality which correspond to lower coefficient of variation in imep, (COVIMEP in a direct injection compressed natural gas engine employing EGR at relative air-fuel ratios.

  18. Influence of water–air ratio on the heat transfer and creep life of a high pressure gas turbine blade

    International Nuclear Information System (INIS)

    An analytical model to investigate the influence of Water–Air Ratio (WAR) on turbine blade heat transfer and cooling processes (and thus the blade creep life) of industrial gas turbines is presented. The effects of WAR are emphasised for the modelling of the gas properties and the subsequent heat transfer process. The approach considers convective/film cooling and includes the influence of a thermal barrier coating. In addition, the approach is based on the thermodynamic outputs of a gas turbine performance simulation, heat transfer model, as well as a method that accounts for the changes in the properties of moist air as a function of WAR. For a given off-design point, the variation of WAR (0.0–0.10) was investigated using the heat transfer model. Results showed that with increasing WAR the blade inlet coolant temperature reduced along the blade span. The blade metal temperature at each section was reduced as WAR increased, which in turn increased the blade creep life. The increase in WAR increased the specific heat of the coolant and increased the heat transfer capacity of the coolant air flow. The model can be implemented by using the thermodynamic cycle of the engine, without knowing the turbine cooling details in the conceptual design stage. Also, this generic method assists the end user to understand the effect of operating conditions and design parameter on the creep life of a high pressure turbine blade. -- Highlights: • The influence of WAR on gas turbine blade heat transfer and creep life is examined. • Coolant specific heat capacity is the key property affected by changes in WAR. • Increase in WAR reduces the coolant and metal temperature along the blade span. • Creep life increases with increase in WAR even if ambient temperature is increased

  19. Modeling of melt-coolant mixing by bottom injection

    International Nuclear Information System (INIS)

    In this paper, the flow characteristics during the coolant injection, with submerged nozzles, at the bottom of a molten pool are studied. The flow pattern developed by the rising coolant is considered for the case of complete coolant vaporization, and the pool-coolant phase distributions are assessed by a modeling approach delivered from literature for a heterogeneous turbulent jet. To calculate the basic characteristics of such flow, integral relationships are proposed for the two-phase boundary layer. The results of numerical computations and approximate solution are compared with the experimental data obtained in the low temperature experiments, conducted in the DECOBI (debris coolability by bottom injection) facility. (authors)

  20. Design of a molten heavy-metal coolant and target for fast-thermal accelerator driven sub-critical system (ADS)

    International Nuclear Information System (INIS)

    Reactor physics design of a 750 MWth one way coupled fast-thermal ADS was evolved in BARC earlier. This indicated that a fairly large thermal power output was possible with a proton beam of 1 GeV and current 2-3 mA. We also carried out preliminary studies on the molten Pb/Pb-Bi coolant and spallation-target system in the fast zone of this ADS. The thermal power in this zone was estimated to be about 109 MW. In these studies, analyses related to thermal hydraulics have been carried out for a buoyancy driven system to determine the coolant parameters for both lead as well as lead-bismuth eutectic. This design is similar to the passive lead coolant system design of CERN-EA. Appropriate equations for buoyancy pressure head, pressure drop in the reactor core; coolant velocity, heat transport etc. have been solved for different coolant inlet and outlet temperatures, fuel-pin pitch distances, fuel-power densities etc. The analyses show that coolant height required for generating buoyancy pressure head is a very strong function of power density of the fuel-pin and ΔT (difference between outlet and inlet temperature) of the coolant. Main advantage of lead-bismuth eutectic comes from the inlet temperature that can be significantly lower than that of lead; thus larger ΔT can be obtained which in turn will reduce required coolant height. This will result in saving of coolant inventory and cost. In this paper, preliminary engineering design of coolant and target for the 109 MW fast reactor zone is presented. In addition, the proposed Indian programmes to study thermal-hydraulics and materials for the technology development are discussed. (author)

  1. Performance Investigation of Automobile Radiator Operated with ZnFe2O4 Nano Fluid based Coolant

    OpenAIRE

    Tripathi Ajay; Chandra H

    2015-01-01

    The cooling system of an Automobile plays an important role in its performance, consists of two main parts, known as radiator and fan. Improving thermal efficiency of engine leads to increase the engine's performance, decline the fuel consumption and decrease the pollution emissions. Water and ethylene glycol as conventional coolants have been widely used in radiators of an automotive industry for many years. These heat transfer fluids offer low thermal conductivity. With the advancement of n...

  2. Energetic optimization of the performances of a hot air engine for micro-CHP systems working with a Joule or an Ericsson cycle

    International Nuclear Information System (INIS)

    The micro combined heat and electrical power systems (micro-CHP) with hot air engines are well adapted for solid biomass upgrading, in particular, the Ericsson engines working with an open cycle and an external combustion. This paper presents a model of an Ericsson engine with a compression and an expansion cylinder which allows a thermodynamic optimization of the engine performances in a global approach. A sensitive analysis on the influent parameters is carried out in order to determine the optimal working conditions of the engine: temperature and pressure range, expansion cycle shape with a late intake valve closing or an early exhaust valve closing, heat transfers through the wall of the cylinders. This study, focused on thermodynamic aspects, is a first step in the design of an Ericsson engine. -- Highlights: ► A model of Ericsson engine working with a Joule or Ericsson cycle is presented. ► Influent factors on the engine performances are investigated. ► The heat exchanges in the cylinder wall must be avoided to improve the performances. ► Closing the intake valve late and the exhaust valve early enhances the performances. ► Efficiency, indicated mean pressure, specific work are thermodynamically optimized.

  3. 14C Behaviour in PWR coolant

    International Nuclear Information System (INIS)

    Although 14C is produced in relatively small amounts in PWR coolant, it is important to know its fate, for example whether it is released by gaseous discharge, removed by absorption on ion exchange (IX) resins or deposited on the fuel pin surfaces. 14C can exist in a range of possible chemical forms: inorganic carbon compounds (probably mainly CO2), elemental carbon, and organic compounds such as hydrocarbons. This paper presents results from a preliminary survey of the possible reactions of 14C in PWR coolant. The main conclusions of the study are: - A combination of thermal and radiolytic reactions controls the chemistry of 14C in reactor coolant. A simple chemical kinetic model predicts that CH3OH would be the initial product from radiolytic reactions of 14C following its formation from 17O. CH3OH is predicted to arise as a result of reactions of OH. with CH4 and CH3, and it persists because there is no known radiation chemical reduction mechanism. - Thermodynamic considerations show that CH3OH can be thermally reduced to CH4 in PWR conditions, although formation of CO2 from small organics is the most thermodynamically favourable outcome. Such reactions could be catalysed on active nickel surfaces in the primary circuit. - Limited plant data would suggest that CH4 is the dominant form in PWR and CO2 in BWR. This implies that radiation chemistry may be important in determining the speciation. - Addition of acetate does not affect the amount of 14C formed, but the addition of large amounts of stable carbon would lead to a large range of additional products, some of which would be expected to deposit on fuel pin surfaces as high molecular weight hydrocarbons. However, the subsequent thermal decomposition reactions of these products are not known. - Acetate addition may represent a small input of 12C compared with organic material released from CVCS resins, although the importance of this may depend on whether that is predominantly soluble material or suspended

  4. 1996 Idaho National Engineering and Environmental Laboratory (INEEL) National Emissions Standards for Hazardous Air Pollutants (NESHAPs) -- Radionuclides. Annual report

    International Nuclear Information System (INIS)

    Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, ''National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities,'' each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1996. The Idaho Operations Office of the DOE is the primary contact concerning compliance with the National Emission Standards for Hazardous Air Pollutants (NESHAPs) at the INEEL. For calendar year 1996, airborne radionuclide emissions from the INEEL operations were calculated to result in a maximum individual dose to a member of the public of 3.14E-02 mrem (3.14E-07 Sievert). This effective dose equivalent (EDE) is well below the 40 CFR 61, Subpart H, regulatory standard of 10 mrem per year (1.0E-04 Sievert per year)

  5. Engineering Schottky contacts in open-air fabricated heterojunction solar cells to enable high performance and ohmic charge transport.

    Science.gov (United States)

    Hoye, Robert L Z; Heffernan, Shane; Ievskaya, Yulia; Sadhanala, Aditya; Flewitt, Andrew; Friend, Richard H; MacManus-Driscoll, Judith L; Musselman, Kevin P

    2014-12-24

    The efficiencies of open-air processed Cu2O/Zn(1-x)Mg(x)O heterojunction solar cells are doubled by reducing the effect of the Schottky barrier between Zn(1-x)Mg(x)O and the indium tin oxide (ITO) top contact. By depositing Zn(1-x)Mg(x)O with a long band-tail, charge flows through the Zn(1-x)Mg(x)O/ITO Schottky barrier without rectification by hopping between the sub-bandgap states. High current densities are obtained by controlling the Zn(1-x)Mg(x)O thickness to ensure that the Schottky barrier is spatially removed from the p-n junction, allowing the full built-in potential to form, in addition to taking advantage of the increased electrical conductivity of the Zn(1-x)Mg(x)O films with increasing thickness. This work therefore shows that the Zn(1-x)Mg(x)O window layer sub-bandgap state density and thickness are critical parameters that can be engineered to minimize the effect of Schottky barriers on device performance. More generally, these findings show how to improve the performance of other photovoltaic system reliant on transparent top contacts, e.g., CZTS and CIGS. PMID:25418326

  6. Validation on the lead coolant technology for BREST reactors

    International Nuclear Information System (INIS)

    The operating experience of reactor facilities with a lead-bismuth coolant and a complex of R and D work done to validate facilities with a lead coolant convince that the coolant technology issues require urgent solution also for the BREST-OD-300 facility. The coolant technology issues include a complex of measures, processes and devices to be developed to ensure the cleanliness of the reactor and heat exchanging surfaces and ensure anti-corrosion protection of materials. In the long run, the coolant technology relates the most important list of issues that determine the preservation of the reactor facility's design thermal-hydraulic characteristics and its trouble-free operation. The coolant technology priorities and capabilities for implementing this technology have been determined for the BREST-OD-300 reactor facility. With regard for the quantitative prediction of all impurity sources for the BREST-OD-300 conditions, key technical concepts for the coolant technology systems have been proposed and validated, including the following: 1. To clean the coolant and the circuit surfaces at the BREST-OD-300 facility, it is proposed to use a hydrogen recovery process based on hydrogen reduction of the lead oxide impurities to lead and its return to the coolant. The hydrogen recovery process in the BREST-OD-300 facility is implemented through introduction of a hydrogen-containing gas mixture immediately to the circulating alloy flow. To exclude negative hydrogen effects on protective passivating films of structural materials, water vapour is added to the reduction gas mixture. 2. To clean the coolant of impurities other than reduced by hydrogen, the BREST-OD-300 facility includes filters. They are used to clean the coolant of oxidized impurities of structural materials that enter the coolant through diffusion, erosion or other processes. 3. To prevent the primary circuit gas volume making dusty in the BREST-OD-300 facility, it will have a special aerosol cleaning system

  7. Analysis and Design of a Dish/Stirling System for Solar Electric Generation with a 2.7 kW Air-Cooled Engine

    Directory of Open Access Journals (Sweden)

    Beltrán-Chacón R.

    2012-01-01

    Full Text Available This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, since the design of the cooler needs greater amounts of heat removal by increasing the air flow without affecting the internal conditions of the process (mass flow of working gas and internal dimensions of the same. The system was optimized and achieves an overall efficiency of solar to electric energy conversion of 26.7%. This study shows that the use of an air-cooled Stirling engine is potentially attractive for power generation at low capacities.

  8. Analysis of coolant flow and heat transfer in the SSME HPOTP Number 4 bearing assembly

    Science.gov (United States)

    Owens, S. F.; Costes, N. C.

    1990-01-01

    The PHOENICS code has been applied to simulate the flow of liquid oxygen through the number 4 ball bearing assembly of the Space Shuttle Main Engine High-Pressure Oxidizer Turbopump. The Body-Fitted Coordinate system capability of PHOENICS was utilized to create a geometrically accurate model. Effects accounted for by the model include the rotation rate of the calculation domain, viscous heating in the liquid oxygen and two-phase effects due to LOX boiling. A separation program was used to account for conduction within a ball bearing element which was coupled with the PHOENICS flow and heat transfer analysis. Solutions have been obtained for the velocity and temperature fields within the LOX coolant and the temperature within the ball element. The predicted ball temperatures indicate that the coolant is boiling in the region near the ball surface.

  9. Coolant mixing in pressurized water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hoehne, T.; Grunwald, G.

    1998-10-01

    The behavior of PWRs during cold water or boron dilution transients is strongly influenced by the distribution of coolant temperature and boron concentration at the core inlet. This distribution is the needed input to 3-dimensional neutron kinetics to calculate the power distribution in the core. It mainly depends on how the plugs of cold or unborated water formed in a single loop are mixed in the downcomer and in the lower plenum. To simulate such mixture phenomena requires the application of 3-dimensional CFD (computational fluid dynamics) codes. The results of the simulation have to be validated against mixture experiments at scaled facilities. Therefore, in the framework of a research project funded by BMBF, the institute creates a 1:5 mixture facility representing first the geometry of a German pressurized water reactor and later the European Pressurized Water Reactor (EPR) geometry. The calculations are based on the CFD Code CFX-4. (orig.)

  10. Coolant sampling device for a reactor

    International Nuclear Information System (INIS)

    Purpose: To enable accurate measurement of fine quantity of metal impurity in primary coolant by removing unneccessary impurity adhered to a collecting tube when the metal impurity is detected. Constitution: A sampling device is mounted at a recirculating system pipe in a BWR type reactor, a collecting tube is connected to the pipe, a sampled water collecting nozzle is also mounted, and a sluice valve for flowing and shutting off the sampled water is disposed in the vicinity of the nozzle. Acid cleaning liquid which is bubbled by inert gas from a tube provided at the downstream side of the valve cleans the inner surface of the collecting tube over the entire length, thereby effectively removing impurity adhered onto the inner surface of the tube. (Kamimura, M.)

  11. Power module assemblies with staggered coolant channels

    Science.gov (United States)

    Herron, Nicholas Hayden; Mann, Brooks S; Korich, Mark D

    2013-07-16

    A manifold is provided for supporting a power module assembly with a plurality of power modules. The manifold includes a first manifold section. The first face of the first manifold section is configured to receive the first power module, and the second face of the first manifold section defines a first cavity with a first baseplate thermally coupled to the first power module. The first face of the second manifold section is configured to receive the second power module, and the second face of the second manifold section defines a second cavity with a second baseplate thermally coupled to the second power module. The second face of the first manifold section and the second face of the second manifold section are coupled together such that the first cavity and the second cavity form a coolant channel. The first cavity is at least partially staggered with respect to second cavity.

  12. Corrosion products in nuclear reactor coolants

    International Nuclear Information System (INIS)

    In the primary coolant systems of water-cooled nuclear reactors, corrosion products play important roles in controlling the behaviour of structural materials and in determining the optimum conditions for operation. An obvious example in BWRs is the addition of trace elements to the reactor water to control activity transport. Zinc is such an additive that is now well established, and it is clear that its beneficial action depends upon the ability of zinc ions to be incorporated into protective oxides and to make them even more compact and adherent while inhibiting the incorporation of unwanted radio nuclides such as 60Co. In PHWRs and PWRs also, zinc additions should reduce activity transport because the predominant corrosion-product oxides on system surfaces, the chromites and ferrites, are the constituents of BWR oxides that are modified by zinc ions. (author). 32 refs., 5 figs., 6 tabs

  13. Small break loss of coolant accident analysis for the international reactor innovative and secure (IRIS)

    International Nuclear Information System (INIS)

    The pressurized light water cooled, medium power (1000 MWt) IRIS (International Reactor Innovative and Secure) has been under development for four years by an international consortium of over 21 organizations from ten countries. The plant conceptual design was completed in 2001 and the preliminary design is nearing completion. The pre-application licensing process with NRC started in October, 2002 and IRIS is one of the designs considered by US utilities as part of the ESP (Early Site Permit) process. IRIS has been primarily focused on establishing a design with innovative safety characteristics. The first line of defense in IRIS is to eliminate event initiators that could potentially lead to core damage. In IRIS, this concept is implemented through the safety by design approach, briefly discussed in this paper. Because of the safety by design approach, the number and complexity of the safety systems and required operator actions can be minimized in IRIS. The net result is a design with significantly reduced complexity and improved operability, and extensive plant simplifications to enhance construction. This paper focus is on the IRIS response to a small break loss of coolant accident (LOCA). Note that in IRIS large break LOCA events are eliminated by the use of an integral layout configuration in which the reactor vessel contains all the reactor coolant system components including the core, control rod drive mechanisms, pressurizer, steam generators, and coolant pumps. Thus the IRIS integral configuration has no large loop piping; also, no pipes with a diameter greater than 0.1 meters are part of the reactor coolant system boundary. For small break LOCAs, IRIS features an innovative mitigation approach that is based on maintaining coolant inventory rather than providing high and low pressure injection systems to provide makeup coolant to the reactor to maintain core cooling. A brief overview of the IRIS safety concept, describing the simplified engineered

  14. Coolant rate distribution in horizontal steam generator under natural circulation

    Energy Technology Data Exchange (ETDEWEB)

    Blagovechtchenski, A.; Leontieva, V.; Mitrioukhin, A. [St. Petersburg State Technical Univ. (Russian Federation)

    1997-12-31

    In the presentation the major factors determining the conditions of NCC (Natural Coolant Circulation) in the primary circuit and in particular conditions of coolant rate distribution on the horizontal tubes of PGV-1000 in NPP with VVER-1000 under NCC are considered. 5 refs.

  15. Study of neutron noise physical model for reactor coolant boiling

    International Nuclear Information System (INIS)

    The neutron noise method has been used to monitoring reactor coolant boiling. Wach-Kosaly model has been used to interpret the neutron noise induced by coolant boiling. The equation based on the model is got and used for calculation. The physical variable with the relation of bubble's velocity is got from the calculated result (autopower spectral density)

  16. Fuel element transport container with a liquid coolant

    International Nuclear Information System (INIS)

    The transport containers have an inlet duct leading inside and an outlet duct for connecting to coolant pipes. A spray nozzle is connected to the inlet duct, which is directed against the outlet duct. The sensitive parts are therefore protected against overheating when removing the hot coolant. (orig./HP)

  17. Cycle-by-cycle Variations in a Direct Injection Hydrogen Enriched Compressed Natural Gas Engine Employing EGR at Relative Air-Fuel Ratios.

    OpenAIRE

    Olalekan Wasiu Saheed; Rashid A.A.; Baharom Masri

    2014-01-01

    Since the pressure development in a combustion chamber is uniquely related to the combustion process, substantial variations in the combustion process on a cycle-by-cycle basis are occurring. To this end, an experimental study of cycle-by-cycle variation in a direct injection spark ignition engine fueled with natural gas-hydrogen blends combined with exhaust gas recirculation at relative air-fuel ratios was conducted. The impacts of relative air-fuel ratios (i.e. λ = 1.0, 1.2, 1.3 and 1.4 whi...

  18. Dissociated coolant technology and application to experimental installations

    International Nuclear Information System (INIS)

    Thermophysical properties of nitrogen tetroxide used as a coolant in a gas cooled nuclear reactor allow a high specific power density in the core, about 800 to 1200 kW/dm3. Good physical and thermophysical characteristics of the reactor are obtained only for a low volume fraction of coolant in the core, i.e. if the length of heat transfer is minimized. In consequence any deposit on the surface of heat transfer of fuel element is to be avoided. The main parts of the study programme for the use of nitrogen tetroxide as a coolant are the choice of corrosion resistant materials, optimization of coolant composition and inexpensive coolant purification methods

  19. Molten Fuel-Coolant Interactions induced by coolant injection into molten fuel

    International Nuclear Information System (INIS)

    To investigate Molten Fuel-Coolant Interactions (MFCIs) in various contact geometries, an experimental program, called MUSE (MUlti-configurations in Steam Explosions), has been initiated under the ALPHA program at JAERI in Japan. The first series of MUSE test has been focused on the coolant injection (CI) and stratified modes of FCIs using water as coolant and molten thermite as molten fuel. The effects of water jet subcooling, jet dynamics, jet shape and system constraint on FCIs energetic in these modes were experimentally investigated by precisely measuring their mechanical energy release in the MUSE facility. It was observed that measured mechanical energy increased with increasing of jet subcooling in a weakly constraint system but decreased in a strongly constraint system. FCI energetic also increased with increasing of water jet velocity. These results suggested that the penetration and dispersion phenomena of a water jet inside a melt determined the mixing conditions of FCIs in these contact modes and consequently played important roles on FCI energetics. To understand fundamental physics of these phenomena and possible mixing conditions in the MUSE tests, a set of visualization tests with several pairs of jet-pool liquids in non-boiling and isothermal conditions were carried out. Numerical simulations of a water jet penetrating into a water pool at non-boiling conditions showed similar behaviors to those observed in the visualization tests. (author)

  20. Analysis of accidental loss of pool coolant due to leakage in a PWR SFP

    International Nuclear Information System (INIS)

    Highlights: • Accidental loss of pool coolant due to leakage in a PWR SFP was studied using MAAP5. • The effect of emergency ventilation on the accident progression was investigated. • The effect of emergency injection on the accident progression was discussed. - Abstract: A large loss of pool coolant/water accident may be caused by extreme accidents such as the pool wall or bottom floor punctures due to a large aircraft strike. The safety of SFP under this circumstance is very important. Large amounts of radioactive materials would be easily released into the environment if a severe accident happened in the SFP, because the spent fuel pool (SFP) in a PWR nuclear power station (NPS) is often located in the fuel handing building outside the reactor containment. To gain insight into the loss of pool coolant accident progression for a pressurized water reactor (PWR) SFP, a computational model was established by using the Modular Accident Analysis Program (MAAP5). Important factors such as Zr oxidation by air, air natural circulation and thermal radiation were considered for partial and complete drainage accidents without mitigation measures. The calculation indicated that even if the residual water level was in the active fuel region, there was a chance to effectively remove the decay heat through axial heat conduction (if the pool cooling system failed) or steam cooling (if the pool cooling system was working). For sensitivity study, the effects of emergency ventilation and water injection on the accident progression were analyzed. The analysis showed that for the current configuration of high-density storage racks, it was difficult to cool the spent fuels by air natural circulation. Enlarging the space between the adjacent assemblies was a way of increasing air natural circulation flow rate and maintaining the coolability of SFP. Water injection to the bottom of the SFP helped to recover water inventory, quenching the high temperature assemblies to prevent

  1. Experimental and theoretical analysis of effects of N2, O2 and Ar in excess air on combustion and NOx emissions of a turbocharged NG engine

    International Nuclear Information System (INIS)

    Highlights: • We defined 7 effects of excess air and quantitative indicators on NOx emissions. • Contributions of N2, O2 and Ar on the thermal effect are separately 85%, 14% and 1%. • Contributions of N2 and Ar on the dilution effect are 98.8% and 1.2%, respectively. • The high level of N2 in air is the main reason why NOx emissions decrease with λ. - Abstract: This paper presents the effects of N2, O2 and Ar in excess air on combustion and NOx emissions of a natural gas spark-ignition engine. Based on Arrhenius Law and Zeldovich Mechanism, seven different kinds of effects were defined as well as their quantitative indicators. Excess air and N2 were separately added into the intake charge with fuel remaining unchanged in a 6-cylinder turbocharged natural gas engine. The results show that the essential reason why NOx emissions vary with increasing excess air ratio (λ) is that the oxidation effect of O2 varies with the in-cylinder temperature, which is controlled by the thermal effect of excess air. The contributions of N2, O2 and Ar on the thermal effect are 82.6–86.1%, 13.3–16.7% and 0.6–0.7%, respectively. The chemical effect of O2 is fully offset by the dilution effect of N2 and Ar. The contributions of N2 and Ar on the dilution effect are 98.31% and 1.69%, respectively. The increase of NOx emissions caused by O2 is found to be increased first and then decreased with increasing λ. From the view of the composition of air, the high level of N2 is the main reason why NOx emissions decrease significantly with increasing λ

  2. Statistical analysis of the Ft. Calhoun reactor coolant pump system

    International Nuclear Information System (INIS)

    In engineering science, statistical quality control techniques have traditionally been applied to control manufacturing processes. An application to commercial nuclear power plant maintenance and control is presented that can greatly improve plant safety. As a demonstration of such an approach to plant maintenance and control, a specific system is analyzed: the reactor coolant pumps (RCPs) of the Ft. Calhoun nuclear power plant. This research uses capability analysis, Shewhart X-bar, R-charts, canonical correlation methods, and design of experiments to analyze the process for the state of statistical control. The results obtained show that six out of ten parameters are under control specifications limits and four parameters are not in the state of statistical control. The analysis shows that statistical process control methods can be applied as an early warning system capable of identifying significant equipment problems well in advance of traditional control room alarm indicators Such a system would provide operators with ample time to respond to possible emergency situations and thus improve plant safety and reliability. (author)

  3. Reactor water chemistry relevant to coolant-cladding interaction

    International Nuclear Information System (INIS)

    The report is a summary of the work performed in a frame of a Coordinated Research Program organized by the IAEA and carried out from 1981 till 1986. It consists of a survey on our knowledge on coolant-cladding interaction: the basic phenomena, the relevant parameters, their control and the modelling techniques implemented for their assessment. Based upon the results of this Coordinated Research Program, the following topics are reviewed on the report: role of water chemistry in reliable operation of nuclear power plants; water chemistry specifications and their control; behaviour of fuel cladding materials; corrosion product behaviour and crud build-up in reactor circuits; modelling of corrosion product behaviour. This report should be of interest to water chemistry supervisors at the power plants, to experts in utility engineering departments, to fuel designers, to R and D institutes active in the field and to the consultants of these organizations. A separate abstract was prepared for each of the 3 papers included in the Annex of this document. Refs, figs, tabs

  4. DBD Plasma Actuators for Flow Control in Air Vehicles and Jet Engines - Simulation of Flight Conditions in Test Chambers by Density Matching

    Science.gov (United States)

    Ashpis, David E.; Thurman, Douglas R.

    2011-01-01

    Dielectric Barrier Discharge (DBD) Plasma actuators for active flow control in aircraft and jet engines need to be tested in the laboratory to characterize their performance at flight operating conditions. DBD plasma actuators generate a wall-jet electronically by creating weakly ionized plasma, therefore their performance is affected by gas discharge properties, which, in turn, depend on the pressure and temperature at the actuator placement location. Characterization of actuators is initially performed in a laboratory chamber without external flow. The pressure and temperature at the actuator flight operation conditions need to be simultaneously set in the chamber. A simplified approach is desired. It is assumed that the plasma discharge depends only on the gas density, while other temperature effects are assumed to be negligible. Therefore, tests can be performed at room temperature with chamber pressure set to yield the same density as in operating flight conditions. The needed chamber pressures are shown for altitude flight of an air vehicle and for jet engines at sea-level takeoff and altitude cruise conditions. Atmospheric flight conditions are calculated from standard atmosphere with and without shock waves. The engine data was obtained from four generic engine models; 300-, 150-, and 50-passenger (PAX) aircraft engines, and a military jet-fighter engine. The static and total pressure, temperature, and density distributions along the engine were calculated for sea-level takeoff and for altitude cruise conditions. The corresponding chamber pressures needed to test the actuators were calculated. The results show that, to simulate engine component flows at in-flight conditions, plasma actuator should be tested over a wide range of pressures. For the four model engines the range is from 12.4 to 0.03 atm, depending on the placement of the actuator in the engine. For example, if a DBD plasma actuator is to be placed at the compressor exit of a 300 PAX engine, it

  5. Evaluation of alternate secondary (and tertiary) coolants for the molten-salt breeder reactor

    International Nuclear Information System (INIS)

    The three most promising coolant selections for an MSBR have been identified and evaluated in detail from the many coolants considered for application either as a secondary coolant in 1000-MW(e) MSBR configurations using only one coolant, or as secondary and tertiary coolants in an MSBR dual coolant configuration employing two different coolants. These are, as single secondary coolants: (1) a ternary sodium--lithium--beryllium fluoride melt; (2) the sodium fluoroborate--sodium fluoride eutectic melt, the present reference design secondary coolant. In the case of the dual coolant configuration, the preferred system is molten lithium--beryllium fluoride (Li2BeF4) as the secondary coolant and helium gas as the tertiary coolant

  6. Characterization of air/fuel mixture and combustion processes in a DISI engine through advanced optical and X-ray based diagnostics

    OpenAIRE

    Marchitto, Luca

    2015-01-01

    The present dissertation has investigated the influence of injection parameters on air/fuel mixture and combustion processes in a DISI engine, through advanced diagnostics. It is possible to distinguish three parts of the work: the spray macroscopic parameters characterization, the spray break-up investigation and the study of the effects of injection timing and duration on the combustion process. In the first stage, the influence of injection pressure and duration on the fuel mass rate a...

  7. The start-up of a gas turbine engine using compressed air tangentially fed onto the blades of the basic turbine

    Science.gov (United States)

    Slobodyanyuk, L. K.; Dayneko, V. I.

    1983-01-01

    The use of compressed air was suggested to increase the reliability and motor lifetime of a gas turbine engine. Experiments were carried out and the results are shown in the form of the variation in circumferential force as a function of the entry angle of the working jet onto the turbine blade. The described start-up method is recommended for use with massive rotors.

  8. 77 FR 36341 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Science.gov (United States)

    2012-06-18

    ...EPA is adopting several new aircraft engine emission standards for oxides of nitrogen (NOX), compliance flexibilities, and other regulatory requirements for aircraft turbofan or turbojet engines with rated thrusts greater than 26.7 kilonewtons (kN). We also are adopting certain other requirements for gas turbine engines that are subject to exhaust emission standards as follows.......

  9. ISS Internal Active Thermal Control System (IATCS) Coolant Remediation Project

    Science.gov (United States)

    Morrison, Russell H.; Holt, Mike

    2005-01-01

    The IATCS coolant has experienced a number of anomalies in the time since the US Lab was first activated on Flight 5A in February 2001. These have included: 1) a decrease in coolant pH, 2) increases in inorganic carbon, 3) a reduction in phosphate buffer concentration, 4) an increase in dissolved nickel and precipitation of nickel salts, and 5) increases in microbial concentration. These anomalies represent some risk to the system, have been implicated in some hardware failures and are suspect in others. The ISS program has conducted extensive investigations of the causes and effects of these anomalies and has developed a comprehensive program to remediate the coolant chemistry of the on-orbit system as well as provide a robust and compatible coolant solution for the hardware yet to be delivered. The remediation steps include changes in the coolant chemistry specification, development of a suite of new antimicrobial additives, and development of devices for the removal of nickel and phosphate ions from the coolant. This paper presents an overview of the anomalies, their known and suspected system effects, their causes, and the actions being taken to remediate the coolant.

  10. MATLAB/Simulink Framework for Modeling Complex Coolant Flow Configurations of Advanced Automotive Thermal Management Systems

    Energy Technology Data Exchange (ETDEWEB)

    Titov, Gene; Lustbader, Jason; Leighton, Daniel; Kiss, Tibor

    2016-04-05

    The National Renewable Energy Laboratory's (NREL's) CoolSim MATLAB/Simulink modeling framework was extended by including a newly developed coolant loop solution method aimed at reducing the simulation effort for arbitrarily complex thermal management systems. The new approach does not require the user to identify specific coolant loops and their flow. The user only needs to connect the fluid network elements in a manner consistent with the desired schematic. Using the new solution method, a model of NREL's advanced combined coolant loop system for electric vehicles was created that reflected the test system architecture. This system was built using components provided by the MAHLE Group and included both air conditioning and heat pump modes. Validation with test bench data and verification with the previous solution method were performed for 10 operating points spanning a range of ambient temperatures between -2 degrees C and 43 degrees C. The largest root mean square difference between pressure, temperature, energy and mass flow rate data and simulation results was less than 7%.

  11. Chemistry of liquid metal coolants and matrices for radioactive waste immobilization

    International Nuclear Information System (INIS)

    Liquid sodium is used as coolant in fast breeder reactors. Heavy liquid metals, namely lead- and lead-bismuth eutectic alloys are used as coolant in accelerator driven systems (ADS) wherein the minor actinides are burnt with simultaneous generation of electrical power. The structural materials that contain these coolants in the heat transport circuits are special grade steels that meet the requirements of high temperature mechanical properties. While liquid sodium in its pure state is quite compatible with structural steels, enhanced corrosion and mass transport occur when dissolved oxygen level in sodium increases demanding a precise control of this impurity in sodium. In the liquid lead based coolant systems, corrosion owing to high solubility of the alloying elements of steels in the coolants is significant. But, this is mitigated by forming a passive oxide layer on the surface of the steel by a careful control of dissolved oxygen in the liquid metal coolant. Understanding the thermochemical and kinetic aspects of the chemical reactions that occur in these coolant circuits is essential for successful exploitation of oxygen control in these reactor systems. Studies on Na-M-O, Pb-M-O and Bi-M-O systems are of relevance for this purpose. Sensors for continuous on-line monitoring of dissolved oxygen in these high temperature liquid metal coolant circuits are also needed. In fast breeder reactors, sensors for on-line monitoring of hydrogen in liquid sodium and in the argon cover gas are required to detect a possible steam leak at the steam generator section of the coolant circuit. High temperature electrochemical cells based on hydride ion conductors are candidates for the application in liquid sodium. Thermochemical and electrical properties of the hydride ion conducting systems are therefore explored. Compact sensors for monitoring trace levels of hydrogen impurity in the argon cover gas are also being developed. By suitable choice of material and their

  12. Dose reduction in NRU reactor coolant

    Energy Technology Data Exchange (ETDEWEB)

    Gubbala, N.P.; Stuart, C.R.; Rudzinski, H. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2011-07-01

    The reduction of radiation dose exposure to operations and maintenance personnel is an important objective for an operating nuclear reactor. The National Research Universal (NRU) is a heavy-water cooled and moderated research reactor that uses aluminum clad fuel in an aluminum reactor vessel. The tramp uranium and activated corrosion products of aluminum, {sup 28}Al, characterized as non-ionic particulates, provide the largest contributions to radiation fields during reactor operation. The heavy water coolant purification system consists of an evaporator, mechanical filters, and mixed bed ion exchange (IX) columns. The evaporator alone provides a purification half-life of 12 days. However, the existing mechanical filters and the mixed bed ion exchange columns are not effective at removing the non-ionic particulates and reducing the radiation fields. Operation with a modified ion exchange column in parallel with the evaporator has resulted in a reduction in the concentration of uranium from 10.0 to 1.5 μg/kg in four and half months. Over the same period, the radiation field has decreased to 2.0 R/h, one half of the historical value. (author)

  13. Dose reduction in NRU reactor coolant

    International Nuclear Information System (INIS)

    The reduction of radiation dose exposure to operations and maintenance personnel is an important objective for an operating nuclear reactor. The National Research Universal (NRU) is a heavy-water cooled and moderated research reactor that uses aluminum clad fuel in an aluminum reactor vessel. The tramp uranium and activated corrosion products of aluminum, 28Al, characterized as non-ionic particulates, provide the largest contributions to radiation fields during reactor operation. The heavy water coolant purification system consists of an evaporator, mechanical filters, and mixed bed ion exchange (IX) columns. The evaporator alone provides a purification half-life of 12 days. However, the existing mechanical filters and the mixed bed ion exchange columns are not effective at removing the non-ionic particulates and reducing the radiation fields. Operation with a modified ion exchange column in parallel with the evaporator has resulted in a reduction in the concentration of uranium from 10.0 to 1.5 μg/kg in four and half months. Over the same period, the radiation field has decreased to 2.0 R/h, one half of the historical value. (author)

  14. Characterization of reactor coolant by XRF

    International Nuclear Information System (INIS)

    The analyzes of membrane filters is of utmost importance in characterizing the coolant chemistry in nuclear power plants. Traditional analyzes of filters includes oxidative digestion followed by instrumental analyzes. XRF (X-ray Fluorescence spectrometry) can analyze without digestion of the filters. The method is much faster and demands only a cutting step as sample preparation. By use of XRF the analytical laboratory at the Halden Reactor Project will get increased capacity, which makes it possible to analyze more samples and improve the characterization of the water. The method has shown to give more stable results than other methods in use, and has proved to have good precision. New calibration methods have been developed and tested successfully against other methods. A round robin test, attending seven laboratories from nuclear power plants, was initiated by the Halden Project to verify the instrument. The test of standard cation exchange filters showed that conventional filter digestion results in too low values. The XRF methodology shows very good agreement with the standard values. The round robin test for particle filters could not confirm that filter digestion results in too low values. This was mainly due to lack of standard particle filters and large scatter in the reported data. (author)

  15. Corrosion problems with aqueous coolants, final report

    Energy Technology Data Exchange (ETDEWEB)

    Diegle, R B; Beavers, J A; Clifford, J E

    1980-04-11

    The results of a one year program to characterize corrosion of solar collector alloys in aqueous heat-transfer media are summarized. The program involved a literature review and a laboratory investigation of corrosion in uninhibited solutions. It consisted of three separate tasks, as follows: review of the state-of-the-art of solar collector corrosion processes; study of corrosion in multimetallic systems; and determination of interaction between different waters and chemical antifreeze additives. Task 1 involved a comprehensive review of published literature concerning corrosion under solar collector operating conditions. The reivew also incorporated data from related technologies, specifically, from research performed on automotive cooling systems, cooling towers, and heat exchangers. Task 2 consisted of determining the corrosion behavior of candidate alloys of construction for solar collectors in different types of aqueous coolants containing various concentrations of corrosive ionic species. Task 3 involved measuring the degradation rates of glycol-based heat-transfer media, and also evaluating the effects of degradation on the corrosion behavior of metallic collector materials.

  16. Reactor coolant pump monitoring and diagnostic system

    International Nuclear Information System (INIS)

    In order to reliably and safely operate a nuclear power plant, it is necessary to continuously monitor the performance of numerous subsystems to confirm that the plant state is within its prescribed limits. An important function of a properly designed monitoring system is the detection of incipient faults in all subsystems (with the avoidance of false alarms) coupled with an information system that provides the operators with fault diagnosis, prognosis of fault progression and recommended (either automatic or prescriptive) corrective action. In this paper, such a system is described that has been applied to reactor coolant pumps. This system includes a sensitive pattern-recognition technique based upon the sequential probability ratio test (SPRT) that detects incipient faults from validated signals, an expert system embodying knowledge bases on pump and sensor performance, extensive hypertext files containing operating and emergency procedures as well as pump and sensor information and a graphical interface providing the operator with easily perceived information on the location and character of the fault as well as recommended corrective action. This system is in the prototype stage and is currently being validated utilizing data from a liquid-metal cooled fast reactor (EBR-II). 3 refs., 4 figs

  17. Low-activation lead coolant for advanced small modular NPP

    International Nuclear Information System (INIS)

    The purpose of the paper is in studying perspectives of a new heavy liquid metal coolant for a small fast reactor (FR) concept. To reduce the post irradiation activity of the coolant the using of lead isotope, Pb-206, instead of natural lead, Pb-nat, is offered. In this case the accumulation of such hazardous radionuclides, as Po-210, Bi-208, Bi-207, essentially decreases. The interval of the lead-206 coolant cost which does not exceed 20% of the overall FR cost is estimated. The possibility of lead-206 obtaining for FR needs with the centrifugal separation technique is pointed out. (author)

  18. Effect of coolant vapor quality on rewetting phenomena

    International Nuclear Information System (INIS)

    The effect of the coolant vapor quality on the rewetting process in bottom flooding has been experimentally studied. The flow visualization showed that when the coolant vapor quality was greater than about 1%, a completely different flow pattern was noted from that observed when the coolant had no vapor quality. For a given test condition, an increasing vapor quality was accompanied by an increasing rewetting velocity. The results from the experiment are discussed in terms of the deduced heat transfer coefficient distribution and rewetting temperature. (author)

  19. The first CAGR coolant experiment using instrumented fuel

    International Nuclear Information System (INIS)

    Small additions of carbon monoxide and methane to the AGR carbon dioxide coolant inhibit the corrosion of the moderator. In sufficient quantities these will cause carbon deposits on the fuel pins, with unacceptable deterioration of heat transfer. This paper describes the first experiment using instrumented stringers in a programme to find coolants allowing adequate moderator life with minimal deposition. It is shown that it is possible, albeit with considerable effort, to perform a successful experiment in a commercial operating reactor. The first coolant tested was non-depositing, within the errors, giving a potential six year increase in moderator life. (author)

  20. Recent developments in coolant systems for Indus Accelerator Complex at RRCAT, Indore

    International Nuclear Information System (INIS)

    Scarcity of fresh water forces mankind to explore other possible water sources that can meet the increasing demand of coolants in industries, R and D sectors and other establishments where water is used as coolant. It also becomes a challenge for water chemist to control water chemistry to keep the equipments/devices intact during its operation using water as coolant. Deionised (DI) and soft water have been used as coolants for Indus Accelerator Complex, RRCAT, Indore. DI water is produced and its quality is maintained either by conventional ion exchange method or a hybrid method of membrane separation and ion exchange technique. This requires handling of corrosive chemicals, manpower, space for plant installation, and a long array of water treatment units. CSL has implemented the idea of rain water harvesting to produce DI water after systematic studies in laboratory. The concerning issues are reduced to almost one-fourth by using rain water to produce DI water. The harvesting system has been in use for last three years. Heat is dissipated into air by evaporation of soft water in cooling tower. Requirement of soft water makeup has been estimated to be about 40,000 ltrs. / day (max.) if the machine is operated at its designed specifications. Non-availability of soft water (which circulates in open loop) may lead to shut down like situation and looking for alternate source becomes quite essential. Laboratory studies (water analysis and treatment) on sewage water (available 1,00,000 ltrs/day) from RRCAT colony as a possible source of producing soft water show promising result. (author)

  1. Lead Coolant Test Facility Technical and Functional Requirements, Conceptual Design, Cost and Construction Schedule

    Energy Technology Data Exchange (ETDEWEB)

    Soli T. Khericha

    2006-09-01

    This report presents preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic. Based on review of current world lead or lead-bismuth test facilities and research need listed in the Generation IV Roadmap, five broad areas of requirements of basis are identified: Develop and Demonstrate Prototype Lead/Lead-Bismuth Liquid Metal Flow Loop Develop and Demonstrate Feasibility of Submerged Heat Exchanger Develop and Demonstrate Open-lattice Flow in Electrically Heated Core Develop and Demonstrate Chemistry Control Demonstrate Safe Operation and Provision for Future Testing. These five broad areas are divided into twenty-one (21) specific requirements ranging from coolant temperature to design lifetime. An overview of project engineering requirements, design requirements, QA and environmental requirements are also presented. The purpose of this T&FRs is to focus the lead fast reactor community domestically on the requirements for the next unique state of the art test facility. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 420oC. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M. It is also estimated that the facility will require two years to be constructed and ready for operation.

  2. PFI 氢内燃机的氢-空气混合特性%Hydrogen-air Mixture Characteristics of PFI Hydrogen Internal Combustion Engine

    Institute of Scientific and Technical Information of China (English)

    段俊法; 刘福水; 孙柏刚

    2014-01-01

    以1台4缸进气道燃料喷射内燃机为基础,建立了包含进气管道和气缸的氢内燃机进气系统三维仿真模型。提出用混合气不均匀性系数来评价氢-空气混合状况,仿真研究了氢内燃机边界条件下的进气气流运动规律和混合过程,发现氢-空气混合状况主要取决于气流的搬运作用和扩散面积。探讨了氢气喷射相位和喷射压力对氢-空气混合速度和混合均匀性的影响,并以不均匀性系数为指标优化了 PFI氢内燃机不同转速和当量比下的喷射相位与喷射压力。%A 3D simulation model of air intake system including intake pipe and cylinder was built based on a 4-cylinder and in-take port fuel injection hydrogen internal combustion engine .The non-uniformity coefficient was put forward to evaluate the mixing condition of hydrogen-air mixture .The intake air flow movement and mixing process of hydrogen internal combustion engine in the boundary conditions was simulated and researched with the model .It was found that the key factors for mixing condition were airflow carrying function and diffusion area .In addition ,the influence of hydrogen injection pressure and timing on hydrogen-air mixing velocity and uniformity was investigated and the injection timing and pressure of different engine speed and equivalent ratio were optimized according to the non-uniformity coefficients .

  3. Effects of Scavenging System Configuration on In-Cylinder Air Flow Organization of an Opposed-Piston Two-Stroke Engine

    Directory of Open Access Journals (Sweden)

    Fukang Ma

    2015-06-01

    Full Text Available In-cylinder air flow is very important from the point of view of mixture formation and combustion. In this direction, intake chamber structure and piston crown shape play a very crucial role for in-cylinder air pattern of opposed-piston two-stroke (OP2S engines. This study is concerned with the three-dimensional (3D computational fluid dynamics (CFD analysis of in-cylinder air motion coupled with the comparison of predicted results with the zero-dimensional (0D parametric model. Three configurations viz., a flat piston uniform scavenging chamber, a flat piston non-uniform scavenging chamber and a pit piston non-uniform scavenging chamber have been studied. 0D model analysis of in-cylinder air flow is consistent with 3D CFD simulation. It is concluded that a pit piston non-uniform scavenging chamber is the best design from the point of view of tumble ratio, turbulent kinetic energy and turbulent intensity, which play very important roles in imparting proper air motion. Meanwhile a flat piston uniform scavenging chamber can organize a higher swirl ratio and lower tumble ratio which is important to improve the scavenging process.

  4. Transient two-phase performance of LOFT reactor coolant pumps

    International Nuclear Information System (INIS)

    Performance characteristics of Loss-of-Fluid Test (LOFT) reactor coolant pumps under transient two-phase flow conditions were obtained based on the analysis of two large and small break loss-of-coolant experiments conducted at the LOFT facility. Emphasis is placed on the evaluation of the transient two-phase flow effects on the LOFT reactor coolant pump performance during the first quadrant operation. The measured pump characteristics are presented as functions of pump void fraction which was determined based on the measured density. The calculated pump characteristics such as pump head, torque (or hydraulic torque), and efficiency are also determined as functions of pump void fractions. The importance of accurate modeling of the reactor coolant pump performance under two-phase conditions is addressed. The analytical pump model, currently used in most reactor analysis codes to predict transient two-phase pump behavior, is assessed

  5. Liquid metal coolants for space nuclear power units

    International Nuclear Information System (INIS)

    The consideration is given to the results of investigations conducting in IPPE from the 1950s on the technology and heat transfer of liquid metal coolants (lithium and sodium-potassium eutectic alloy) of space nuclear power plants (SNPP). The advantage of lithium coolant is its low density, splendid heat-transfer properties, high boiling point, low saturated vapor pressure, low activation when passing through reactor core, etc. Its disadvantage is high melting point and the higher corrosion activity than sodium-potassium alloy one. Prospects of lithium coolant use in developing current powerful SNPP are shown. Reliable operation of liquid metal part (with sodium-potassium coolant) of SNPP of low power and limited life at satellites launching in the USSR in 1970-80s is pointed out

  6. Simulation of a loss of coolant accident

    International Nuclear Information System (INIS)

    An essential component of nuclear safety activities is the analysis of postulated accidents which are taken as a design basis for a facility. This analysis is usually carried out by using complex computer codes to simulate the behaviour of the plant and to calculate vital plant parameters, which are then compared with the design limits. Since these simulations cannot be verified at the plant itself, computer codes must be validated by comparing the results of calculations with experimental data obtained in test facilities. With this objective in mind, the Central Research Institute for Physics (CRIP) of the Hungarian Academy of Sciences designed and constructed the PMK-NVH (Paks Model Circuit) test facility, a scaled down model of the WWER-440 Paks nuclear power plant. Hungary with the aim of strengthening the international co-operation on nuclear safety, made the PMK-NVH facility available to the IAEA to conduct a standard problem exercise. In this exercise, experimental data from the simulation of a 7.4% break loss of coolant accident were compared with analytical predictions of the behaviour of the facility calculated with computer codes. This document presents a complete overview of the Standard Problem Exercise, including description of the facility, the experiment, the codes and models used by the participants and a detailed intercomparison of calculated and experimental results. It is recognized that code assessment is a long process which involves many inter-related steps, therefore, no general conclusion on optimum code or best model was reached. However, the exercise was recognized as an important contributor to code validation

  7. Performance analysis of waste heat recovery with a dual loop organic Rankine cycle (ORC) system for diesel engine under various operating conditions

    International Nuclear Information System (INIS)

    Highlights: • Dual loop ORC system is designed to recover waste heat from a diesel engine. • R245fa is used as working fluid for the dual loop ORC system. • Waste heat characteristic under engine various operating conditions is analyzed. • Performance of the combined system under various operating conditions is studied. • The waste heat from coolant and intake air has considerable potential for recovery. - Abstract: To take full advantage of the waste heat from a diesel engine, a set of dual loop organic Rankine cycle (ORC) system is designed to recover exhaust energy, waste heat from the coolant system, and released heat from turbocharged air in the intercooler of a six-cylinder diesel engine. The dual loop ORC system consists of a high temperature loop ORC system and a low temperature loop ORC system. R245fa is selected as the working fluid for both loops. Through the engine test, based on the first and second laws of thermodynamics, the performance of the dual loop ORC system for waste heat recovery is discussed based on the analysis of its waste heat characteristics under engine various operating conditions. Subsequently, the diesel engine-dual loop ORC combined system is presented, and the effective thermal efficiency and the brake specific fuel consumption (BSFC) are chosen to evaluate the operating performances of the diesel engine-dual loop ORC combined system. The results show that, the maximum waste heat recovery efficiency (WHRE) of the dual loop ORC system can reach 5.4% under engine various operating conditions. At the engine rated condition, the dual loop ORC system achieves the largest net power output at 27.85 kW. Compared with the diesel engine, the thermal efficiency of the combined system can be increased by 13%. When the diesel engine is operating at the high load region, the BSFC can be reduced by a maximum 4%

  8. Nuclear reactor coolant pump impeller/shaft assembly

    International Nuclear Information System (INIS)

    A nuclear reactor coolant pump including an impeller and impeller mounting bolt with a plurality of passages formed in the impeller mounting bolt adjacent a portion of the shaft in such a manner that the coolant is effectively pumped through the passegeways to heat the shaft to a temperature approximately equal to that of the impeller, thus creating thermal balance of the pump's component parts and providing improved pump efficiency

  9. Lead-bismuth coolant cleaning from solid impurities using filtration

    International Nuclear Information System (INIS)

    The factors, influencing the efficiency of the circuit cleaning of the lead-bismuth coolant from the solid phase impurities through filtration, are analyzed. The choice of the filtration material is substantiated proceeding from the properties of the given coolant as a dispersion system. The results of the experiments on determining the efficiency of cleaning capacity by retained impurities, throughput and regeneration made it possible to develop the industrial filters for the NPU needs

  10. Adiabatic boiling of two-phase coolant in upward flow

    International Nuclear Information System (INIS)

    A mathematical model of the process of adiabatic boiling (self-condensation) of a two-phase coolant in upward (downward) flow is developed. The model takes account of changes in phase properties with static pressure decrease. The process is investigated numerically. Approximate analytical formulas for design calculations are obtained. It is shown that effects of adiabatic boiling (self-condensation) should be taken into account when calculating two-phase coolant flow in stretched vertical channels

  11. Nuclear modular power stations with lead-based coolant reactors

    International Nuclear Information System (INIS)

    In the present report, the projects of reactors with the lead-based coolant are considered. This class of reactors has the advantages and limitations. The main of advantages is enhanced safety and the main of restrictions is the limitation on power, both originate from natural properties of lead-based coolants. This limitation uniquely determines lead-technology reactors as medium - and small-power systems. (author)

  12. Comparative assessment of thermophysical and thermohydraulic characteristics of lead, lead-bismuth and sodium coolants for fast reactors

    International Nuclear Information System (INIS)

    All prototype, demonstration and commercial liquid metal cooled fast reactors (LMFRs) have used liquid sodium as a coolant. Sodium cooled systems, operating at low pressure, are characterised by very large thermal margins relative to the coolant boiling temperature and a very low structural material corrosion rate. In spite of the negligible thermal energy stored in the liquid sodium available for release in case of leakage, there is some safety concern because of its chemical reactivity with respect to air and water. Lead, lead-bismuth or other alloys of lead, appear to eliminate these concerns because the chemical reactivity of these coolants with respect to air and water is very low. Some experts believe that conceptually, these systems could be attractive if high corrosion activity inherent in lead, long term materials compatibility and other problems will be resolved. Extensive research and development work is required to meet this goal. Preliminary studies on lead-bismuth and lead cooled reactors and ADS (accelerator driven systems) have been initiated in France, Japan, the United States of America, Italy, and other countries. Considerable experience has been gained in the Russian Federation in the course of development and operation of reactors cooled with lead-bismuth eutectic, in particular, propulsion reactors. Studies on lead cooled fast reactors are also under way in this country. The need to exchange information on alternative fast reactor coolants was a major consideration in the recommendation by the Technical Working Group on Fast Reactors (TWGFRs) to collect, review and document the information on lead and lead-bismuth alloy coolants: technology, thermohydraulics, physical and chemical properties, as well as to make an assessment and comparison with respective sodium characteristics

  13. Comparative analysis of coolants for FBR of future nuclear power

    International Nuclear Information System (INIS)

    Selection of a fast reactor (FR) coolant for future nuclear reactors is a complex task that has not a single solution. Safety requirements are expected to grow in the future. The requirements to FR are reconsidered. Gradual transition from the FR as a builder up of plutonium to the FR as an economically effective energy source, is taking place. Among all types of coolants viable for FR, LMC (light molten salt coolants) cover the most complete range of requirements to advanced reactors and have a complete database. Sodium and lead-bismuth coolant (LBC) are selected because there is a complete package of technologies for their handling. Heavy liquid metal coolant (HLMC), being at a disadvantage of heat transfer rate in relation to sodium, make it possible to give the inherent safety properties to the reactor and, as a result, to simplify essentially the reactor design and its safety systems. This results in capital and costs reduction. Neutronic characteristics of HLMC cooled reactors make possible to transmute their own minor actinides (MA) safely, and LBC cooled reactors are able to transmute LWR'MA with high safety characteristics. Basing on the comparison carried out, it can be concluded, that both LBC and sodium are perspective coolants for future FR

  14. Coolant radiologic gas production in SP-100 class reactors

    International Nuclear Information System (INIS)

    Coolant radiologic helium gas production rates were calculated for an SP-100 type reactor using the discrete ordinates code TWODANT. Neutron cross sections were developed from ENDF/B-V data via the MATXS6s master cross section library. Calculations were performed using an S4/P1 approximation and 80 neutron energy groups. Results indicate that the primary helium production reactions in a reactor utilizing 0.1 at. pct Li-6 coolant are (Li-7)(n, n-prime t) (82 percent) followed by (Li-6)(n,t) (16 percent), and (Li-7)(n,gamma) (1 percent). A reactor operating at 2.5 MWt for 7.3 years using 0.1 at. pct Li-6 coolant is predicted to produce approximately 0.16 moles of helium gas in the coolant. For a reactor using natural lithium coolant, gas production is increased to 1.4 moles. A parametric study was conducted which enabled the development of an empirical correlation to predict helium production as a function of coolant Li-6 at. pct and void fraction. 9 refs

  15. Control system of boric acid concentration in coolants or moderators

    International Nuclear Information System (INIS)

    Purpose: To control the boric acid concentration in coolants or the likes in a short time and effectively from the viewpoint of changes in the adsorption amount of ion exchange resins relative to the temperature of the coolants or the likes. Constitution: For the increase of the concentration of boric acid dissolved in coolants or the likes for the control of the reactivity in PWR type reactor, high concentration boric acid is supplied to coolants or the likes recycled through the reactor by a concentration regulation pump to thereby regulate the boric acid concentration. For the decrease of the concentration of boric acid, the coolants or the likes are supplied to a boric acid removing column in an saturated state, where boric acid dissolved in the coolants or the likes are adsorbed and removed by ion exchange resins in the column to thereby regulate the boric acid concentration. The boric acid adsorbed to the ion exchange resins in the column is introduced into a boric acid concentration tank, where the ion exchange resins are regenerated by warm purified water, and the warm purified water and high concentration boric acid are regenerated by the evaporation and condensation of the regenerating liquid. (Moriyama, K.)

  16. Basic knowledge of environmental engineering. Water, air, waste, noise, environmental law. 5. tot. new rev. ed.; Basiswissen Umwelttechnik. Wasser, Luft, Abfall, Laerm und Umweltrecht

    Energy Technology Data Exchange (ETDEWEB)

    Bank, M.

    2007-07-01

    The author is a teacher in Germany's first high school of environmental engineering at Frankenberg/Eder. He was involved in the development of syllabuses in water supply, waste water removal, air pollution abatement, waste prevention and disposal, and noise protection. In teaching practice, it was found that most textbooks were insufficient or outdated, so he decided to write this new textbook. It presents a compact introduction to the technical and legal fundamentals of the four above fields of environmental engineering. Special attention was given to interdependences and interdisciplinary aspects, e.g. waste incineration and air pollution abatement, waste disposal in landfills and leachate treatment, waste resulting from successful water and air purification measures. Cross-references facilitate access to these issues. The book is in four sections, in accordance with its four main subjects. Legal aspects are presented in each chapter. In the fifth section, the four subjects are supplemented by information on general administrative law (licensing procedures.), interdisciplinary legal aspects, and general aspects of environmental management (e.g. eco-audits). (orig.)

  17. Multi-Dimensional Modeling of the Effects of Air Jet and Split Injection on Combustion and Emission of DirectInjection Diesel Engine

    Directory of Open Access Journals (Sweden)

    Mehdi Mansury

    2016-01-01

    Full Text Available One of the most important problems in reducing the emissions of diesel engines is to exchange between the oxides of nitrogen and soot emissions. Fuel multiple injection and air injection into combustion chamber are among the most powerful tools to concurrent reduction of these two emissions. In this research, the effect of multiple injection and air injection on combustion and emission parameters has been studied by AVL fire computational fluid dynamic software. Six states of base and modified combustion chamber have been studied in two different injection patterns including 90 (25 10 and 75 (25 25 mods. Results show that concurrent applying of both multiple injection and air injection methods has resulted in simultaneous reduction of oxide nitrogen and soot pollutants and a negligible loss is seen in the operational parameters of engine. Compression between six studied cases show that the 90 (25 10 mode of injection with modified combustion chamber is the optimum mode by decreasing of soot and oxides of nitrogen emissions about 29% and 20% respectively and 6% indicated power loss in compression to the base combustion chamber and single injection mode. The obtained results from the computational fluid dynamic code have been compared with the existing results in the technical literature and show acceptable behavior.

  18. NANODEVICE: Novel Concepts, Methods, and Technologies for the Production of Portable, Easy-to-use Devices for the Measurement and Analysis of Airborne Engineered Nanoparticles in Workplace Air

    International Nuclear Information System (INIS)

    NANODEVICE is a research project funded by the European Commission in the context of the 7th Framework Programme. The duration is 48 months starting 1st of April 2009. Due to their unique properties, engineered nanoparticles (ENP) are now used for a myriad of novel applications, and have a great economic and technological importance. However, some of these properties, especially their surface reactivity, have raised health concerns due to their potential health effects. There is currently a shortage of field-worthy, cost-effective ways - especially in real time - for reliable assessment of exposure levels to ENP in workplace air. NANODEVICE will provide new information on the physico-chemical properties of engineered nanoparticles (ENP) and information about their toxicology. The main emphasis of the project is in the development of novel measuring devices to assess the exposure to ENP's from workplace air. The purpose of the project is also to promote the safe use of ENP through guidance, standards and education, implementing of safety objectives in ENP production and handling, and promotion of safety related collaborations through an international nanosafety forum. The main project goal is to develop innovative concepts and reliable methods for characterizing ENP in workplace air with novel, portable and easy-to-use devices suitable for workplaces.

  19. NANODEVICE: Novel Concepts, Methods, and Technologies for the Production of Portable, Easy-to-use Devices for the Measurement and Analysis of Airborne Engineered Nanoparticles in Workplace Air

    Science.gov (United States)

    Sirviö, Sari; Savolainen, Kai

    2011-07-01

    NANODEVICE is a research project funded by the European Commission in the context of the 7th Framework Programme. The duration is 48 months starting 1st of April 2009. Due to their unique properties, engineered nanoparticles (ENP) are now used for a myriad of novel applications, and have a great economic and technological importance. However, some of these properties, especially their surface reactivity, have raised health concerns due to their potential health effects. There is currently a shortage of field-worthy, cost-effective ways - especially in real time - for reliable assessment of exposure levels to ENP in workplace air. NANODEVICE will provide new information on the physico-chemical properties of engineered nanoparticles (ENP) and information about their toxicology. The main emphasis of the project is in the development of novel measuring devices to assess the exposure to ENP's from workplace air. The purpose of the project is also to promote the safe use of ENP through guidance, standards and education, implementing of safety objectives in ENP production and handling, and promotion of safety related collaborations through an international nanosafety forum. The main project goal is to develop innovative concepts and reliable methods for characterizing ENP in workplace air with novel, portable and easy-to-use devices suitable for workplaces.

  20. INVESTIGATION OF COMBUSTION, PERFORMANCE AND EMISSION CHARACTERISTICS OF SPARK IGNITION ENGINE FUELLED WITH BUTHANOL – GASOLINE MIXTURE AND A HYDROGEN ENRICHED AIR

    Directory of Open Access Journals (Sweden)

    Alfredas Rimkus

    2016-09-01

    Full Text Available In this study, spark ignition engine fuelled with buthanol-gasoline mixture and a hydrogen-enriched air was investigated. Engine performance, emissions and combustion characteristics were investigated with different buthanol (10% and 20% by volume gasoline mixtures and additionally supplied oxygen and hydrogen (HHO gas mixture (3.6 l/min in the sucked air. Hydrogen, which is in the HHO gas, improves gasoline and gasoline-buthanol mixture combustion, increases indicated pressure during combustion phase and decreases effective specific fuel consumption. Buthanol addition decreases the rate of heat release, the combustion temperature and pressure are lower which have an influence on lower nitrous oxide (NOx emission in exhaust gases. Buthanol lowers hydrocarbon (HC formation, but it increases carbon monoxide (CO concentration and fuel consumption. Combustion process analysis was carried out using AVL BOOST software. Experimental research and combustion process numerical simulation showed that using balanced buthanol and hydrogen addition, optimal efficient and ecological parameters could be achieved when engine is working with optimal spark timing, as it would work on gasoline fuel.

  1. CFD analysis of air ingress distribution during mid-loop accident sequences

    International Nuclear Information System (INIS)

    The accident management approach affects nuclear technology and safety with a new formulation of basic hypotheses for the evaluation of the Source Term and radiological impact on the population due to Fission Product release following Severe Accidents. Considering also the wide spectrum of hypothetical and low probability accident scenarios having these kind of consequences, the sequences having potential for air ingress into the reactor coolant system or involving the interaction between fuel and air, which can flow into the reactor coolant system from the containment, have recently gained more and more interest. The research activities summarised in this paper have been carried out at the Department of Mechanical, Nuclear and Production Engineering of Pisa University, in the frame of an international Project of the IV European Community Framework Programme. The activity included a review of the spectrum of accident sequences to be considered for the investigation of the air ingress probability, the behaviour and the effects of air ingress into the reactor core. Two classes of scenarios were identified for a more in-depth analysis: (a) mid-loop sequences, and (b) scenarios including vessel melt-through. In this frame, mid-loop sequences, having more probabilistic interest than vessel melt-through scenarios, have been investigated by using 3D analytical tools (i.e. Fluent V5.0 fluid-dynamic code). (author)

  2. Line focus by the ellipsoidal and hyperbolic mirrors, and the fabrication of the new type`s heated air engine. 1; Daenmenkyo to sokyokumenkyo ni yoru line focus to shingata netsu kuki engine no shisaku. 1

    Energy Technology Data Exchange (ETDEWEB)

    Shishido, K.; Kazimierski, Z.; Shoji, T. [Tohoku Gakuin University, Sendai (Japan). Faculty of Engineering; Sugiura, M. [Tohoku Gakuin Tsutsujigaoka High School, Sendai (Japan); Kobayashi, Y. [Tokyo Special Glass Co. Ltd., Tokyo (Japan)

    1996-10-27

    Line focusing by ellipsoidal and hyperbolic mirrors was devised for solar heat collection, and the new prototype heated air engine is under fabrication based on such focusing. Ellipse is a locus of the point at which the distance from the 2nd focus is equal to that from the circle with the 1st focus as a center and the major axis as a radius. Hyperbola can be also figured under similar geometric conditions. The link mechanism possible to machine quadratic surfaces based on the above principle has been developed. High-precision quadratic surface mirrors can be fabricated by the link mechanism for convergent solar heat power generation, achieving line focusing of light. The new prototype heated air engine is also proposed which is composed of the heating part by line focusing, cylinder, piston and cooling column. This engine is featured by simple function, light weight, compact body, high efficiency and safety, and is under fabrication. Although conventional converging mirrors use all the mirror surface, the new line focusing uses only the upper part of the mirror, and the lower part is turned over for protection of the mirror from strong wind. 9 figs.

  3. Design study of an air pump and integral lift engine ALF-504 using the Lycoming 502 core

    Science.gov (United States)

    Rauch, D.

    1972-01-01

    Design studies were conducted for an integral lift fan engine utilizing the Lycoming 502 fan core with the final MQT power turbine. The fan is designed for a 12.5 bypass ratio and 1.25:1 pressure ratio, and provides supercharging for the core. Maximum sea level static thrust is 8370 pounds with a specific fuel consumption of 0.302 lb/hr-lb. The dry engine weight without starter is 1419 pounds including full-length duct and sound-attenuating rings. The engine envelope including duct treatment but not localized accessory protrusion is 53.25 inches in diameter and 59.2 inches long from exhaust nozzle exit to fan inlet flange. Detailed analyses include fan aerodynamics, fan and reduction gear mechanical design, fan dynamic analysis, engine noise analysis, engine performance, and weight analysis.

  4. Evaluation of heat exchange performance for air-cooler in HTTR

    International Nuclear Information System (INIS)

    In High Temperature Engineering Test Reactor (HTTR) of 30MW, the generated heat at reactor core is finally dissipated at the air-cooler (ACL) by way of the heat exchangers of the primary pressurized water cooler and the intermediate heat exchanger. To remove generated hear at reactor core and to hold reactor inlet coolant temperature to specified temperature, heat exchangers in main cooling system of HTTR should have designed heat exchange performance. In this report, heat exchange performance for ACL in main cooling system is evaluated with previous operation data, and evaluated values are compared with designed value. Moreover, heat exchange performance at full power operation is estimated for the air temperature. As the result, ACL has heat exchange performance removing generated heat at reactor core under the ACL inlet air temperature of 33 degC. (author)

  5. Analysis of actual status of works on technology of heavy liquid metal coolants

    International Nuclear Information System (INIS)

    Principle duties in heavy liquid metal coolant technology (HLMC) are provision of the purity of coolant and surfaces of circulation loop for maintenance of design thermohydraulic characteristics, prevention of structural materials corrosion and erosion during long service life and present-day safety precautions on different stages of reactor facility operation. For this reason, current HLMC (Pb-Bi, Pb) technology must include coolant pre-operation and charging; monitoring and regulating of coolant oxygen potential; hydrogen purification of coolant and surfaces of circulation loop from lead oxides-based slags; coolant filtration; reactor cover gas purification from coolant aerosols. The current topical problem is personnel training on the questions of HLMC technology

  6. Waste Heat Recovery from the Advanced Test Reactor Secondary Coolant Loop

    Energy Technology Data Exchange (ETDEWEB)

    Donna Post Guillen

    2012-11-01

    This study investigated the feasibility of using a waste heat recovery system (WHRS) to recover heat from the Advanced Test Reactor (ATR) secondary coolant system (SCS). This heat would be used to preheat air for space heating of the reactor building, thus reducing energy consumption, carbon footprint, and energy costs. Currently, the waste heat from the reactor is rejected to the atmosphere via a four-cell, induced-draft cooling tower. Potential energy and cost savings are 929 kW and $285K/yr. The WHRS would extract a tertiary coolant stream from the SCS loop and pump it to a new plate and frame heat exchanger, from which the heat would be transferred to a glycol loop for preheating outdoor air supplied to the heating and ventilation system. The use of glycol was proposed to avoid the freezing issues that plagued and ultimately caused the failure of a WHRS installed at the ATR in the 1980s. This study assessed the potential installation of a new WHRS for technical, logistical, and economic feasibility.

  7. ANALYSIS OF THE IMPACT PROPERTIES OF THE COOLANT RECOVERY SYSTEM HEAT LOSSES OF COMBINED COMPRESSOR-POWER PLANT ON ITS CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Yusha V.L.

    2012-12-01

    Full Text Available The paper presents results of theoretical analysis of the effectiveness of an ideal thermodynamic cycle internal combustion engine combined with an external utilization of exhaust heat. The influence of the properties of the coolant circuit of utilization on its operational parameters and characteristics of the power plant.

  8. Modeling of Coolant Flow in the Fuel Assembly of the Reactor of a Floating Nuclear Power Plant Using the Logos CFD Program

    Science.gov (United States)

    Dmitriev, S. M.; Dobrov, A. A.; Legchanov, M. A.; Khrobostov, A. E.

    2015-09-01

    Results of computer modeling of coolant flow in the fuel assembly of the reactor of a floating nuclear power plant using the LOGOS CFD programs have been given. The possibility of using the obtained results to improve models built into the engineering programs of thermohydraulic calculation of nuclear-reactor cores has been considered.

  9. Engineering Strategies and Methods for Avoiding Air-Quality Externalities: Dispersion Modeling, Home Energy Conservation, and Scenario Planning

    Science.gov (United States)

    Knox, Andrew James

    Energy conservation can improve air quality by reducing emissions from fuel combustion. The human health value retained through better air quality can then offset the cost of energy conservation. Through this thesis' innovative yet widely-accessible combination of air pollution dispersion modeling and atmospheric chemistry, it is estimated that the health value retained by avoiding emissions from Ontario's former coal-fired generating stations is 5.74/MWh (using an upper-bound value of 265,000 per year of life lost). This value is combined with energy modeling of homes in the first-ever assessment of the air-quality health benefits of low-energy buildings. It is shown that avoided health damages can equal 7% of additional construction costs of energy efficient buildings in Ontario. At 7%, health savings are a significant item in the cost analysis of efficient buildings. Looking to energy efficiency in the context of likely future low-resource natural gas scenarios, building efficient buildings today is shown to be more economically efficient than any building retrofit option. Considering future natural gas scarcity in the context of Ontario's Long-Term Energy Plan reveals that Ontario may be forced to return to coal-fired electricity. Projected coal use would result in externalities greater than $600 million/year; 80% more than air-quality externalities from Ontario's electricity in 1985. Radically aggressive investment in electricity conservation (75% reduction per capita by 2075) is one promising path forward that keeps air-quality externalities below 1985 levels. Non-health externalities are an additional concern, the quantification, and ultimately monetization, of which could be practical using emerging air pollution monitoring technologies. Energy, conservation, energy planning, and energy's externalities form a complex situation in which today's decisions are critical to a successful future. It is clear that reducing the demand for energy is essential and

  10. Continuous analysis of radioiodine isotopes in the primary coolant of NPP Paks, Hungary

    International Nuclear Information System (INIS)

    The radioiodine analyser has been installed at the Paks-3 reactor unit. The analyser is based on an efficient and simple method of radioiodine separation: the iodine compound is converted to elementary iodine quantitatively by oxidation with potassium iodate in acid medium. Owing to its volatility, iodine is evaporated quantitatively from the primary coolant (desorption) using air flow. The air is bubbled through a solution of a reducer, and iodine is absorbed in a form which is ready for measurement. A simple NaI(Tl) detector is used for the measurement of gamma spectra. The system is controlled and data are processed by a computer. The analyser displays activity concentration data of the five iodine isotopes periodically every 15 minutes. (M.D.)

  11. Investigations on coolant boiling in research reactors. 2

    International Nuclear Information System (INIS)

    Subcooled boiling has been investigated systematically at the Rossendorf Research Reactor in the range between boiling onset and boiling crisis. This is of particular interest because in the core the direction of the coolant flow is opposite to the bubble buoyance of the bubbles - in contrast to power reactors. For this reason an experimental fuel assembly equipped with a throttle valve for coolant flow reduction and different detectors was built up and installed in the reactor core. Measurements of thermohydraulic parameters and noise signals from temperature, neutron flux and acoustic sources were subject of the investigations. Besides other results fluctuations of the void fraction induced by a standing wave of the two-phase flow in the coolant channel and the 24-Hz pressure fluctuations of the circulation pumps have been observed. It has been shown that the frequency of the standing wave is determined by the size of the boiling volume in the coolant channel and that this frequency therefore depends on the outlet temperature of the coolant. (author)

  12. Coolant mixing and distribution in a transparent reactor model

    International Nuclear Information System (INIS)

    Following a small break loss-of-coolant accident in a pressurized water reactor, coolant water may be injected at high pressure to help cool the core. This paper reports the results of tests which determined the mixing and distribution of the coolant in a 1/5-scale transparent model of the reactor. The model components included the reactor vessel, cold leg pipe, pump, and loop seal with steam generator and hot leg simulators completing the flow loop. Tests were conducted for a no-refill condition with constant liquid inventory in the facility and zero flow of the primary water. Salt water, dyed red was used for the coolant water to create prototypical density differences in this atmospheric facility. Steady state fluid distribution was determined from flow and density measurements and complete mass balances. Interpretation of the quantitative results was aided by extensive flow visualization studies which include still photographs and motion picture films for all tests. The test parameters included the fluid density ratio, the flow rate of coolant water, and the flow rate of primary water injected in the vessel downcomer to simulate a natural circulation flow through vent valves between the reactor core and the downcomer. Four locations of the small break were tested

  13. Nature and behaviour of particulates in PWR coolants

    International Nuclear Information System (INIS)

    Corrosion product species transported by PWR coolants are present in both soluble and insoluble form. Whereas many comparative studies of corrosion products and their activated species refer to the total concentration carried by the coolant, few specifically address the nature and behavior of the insoluble component. The information summarised here is from five Belgian PWRs where continuous-flow capillary samplers were installed as a modification to installed coolant sampling facilities. A series of sampling campaigns were undertaken covering all phases of reactor operations and transient conditions. Particulate populations can vary widely from reactor to reactor and also under steady operational conditions in the same system. Some variation of particle size is apparent with reactor age. During commissioning nickel-rich particles were dominant whereas iron was the major constituent during power operation. It was found that filterable material above 0.1 μm in size could account for between 50 and 90% of total coolant borne activity due to cobalt-58 and 60. Other characteristics of coolant particulates are considered. (author)

  14. The installation welding of pressure water reactor coolant piping

    International Nuclear Information System (INIS)

    Large pressure water reactor nuclear power plants are constructing in our country. There are three symmetry standard loops in reactor coolant system. Each loop possesses a steam generator and a primary poop, in which one of the loops is equipped with a pressurizer. These components are connected with reactor pressure vessel by installation welding of the coolant piping. The integrity of reactor coolant pressure boundary is the second barrier to protect the radioactive substance from release to outside, so the safe operation of nuclear power plant is closely related to the quality of coolant piping installation welding. The heavy tube with super low carbon content austenitic stainless steel is selected for coolant piping. This kind of material has good welding behavior, but the poor thermal conductivity, the big liner expansion coefficient and the big welding deformation will cause bigger welding stress. To reduce the welding deformation, to control the dimension precision, to reduce the residual stress and to ensure the welding quality the installation sequence should be properly designed and the welding technology should be properly controlled. (authors)

  15. Variable cooling circuit for thermoelectric generator and engine and method of control

    Science.gov (United States)

    Prior, Gregory P

    2012-10-30

    An apparatus is provided that includes an engine, an exhaust system, and a thermoelectric generator (TEG) operatively connected to the exhaust system and configured to allow exhaust gas flow therethrough. A first radiator is operatively connected to the engine. An openable and closable engine valve is configured to open to permit coolant to circulate through the engine and the first radiator when coolant temperature is greater than a predetermined minimum coolant temperature. A first and a second valve are controllable to route cooling fluid from the TEG to the engine through coolant passages under a first set of operating conditions to establish a first cooling circuit, and from the TEG to a second radiator through at least some other coolant passages under a second set of operating conditions to establish a second cooling circuit. A method of controlling a cooling circuit is also provided.

  16. Detection of primary coolant leaks in NPP

    International Nuclear Information System (INIS)

    The thermo-hydraulic analyses of the SG box behaviour of Kozloduy NPP units 3 and 4 in case of small primary circuit leaks and during normal operation of the existing ventilation systems in order to determine the detectable leakages from the primary circuit by analysing different parameters used for the purposes of 'Leak before break' concept, performed by ENPRO Consult Ltd. are presented. The following methods for leak detection: measurement of relative air humidity in SG box (can be used for detection of leaks with flow rate 3.78 l/min within one hour at ambient parameters - temperature 400 - 600C and relative humidity form 30% to 60%); measurement of water level in SG box sumps (can not be used for reliable detection of small primary circuit leakages with flow rate about 3.78 l/min); measurement of gaseous radioactivity in SG box( can be used as a general global indication for detection of small leakages from the primary circuit); measurement of condensate flow after the air coolers of P-1 venting system (can be used for primary circuit leak detection) are considered. For determination of the confinement behaviour, a model used with computer code MELCOR has been developed by ENPRO Consult Ltd. A brief summary based on the capabilities of the different methods of leak detection, from the point of view of the applicability of a particular method is given. For both Units 3 and 4 of Kozloduy NPP a qualified complex system for small leak detection is planned to be constructed. Such a system has to unite the following systems: acoustic system for leak detection 'ALUS'; system for control of the tightness of the main primary circuit pipelines by monitoring the local humidity; system for primary circuit leakage detection by measuring condensate run-off in collecting tank after ventilation system P-1 air coolers

  17. Method and apparatus for controlling hybrid powertrain system in response to engine temperature

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Ryan D; Spohn, Brian L; Lehmen, Allen J; Cerbolles, Teresa L

    2014-10-07

    A method for controlling a hybrid powertrain system including an internal combustion engine includes controlling operation of the hybrid powertrain system in response to a preferred minimum coolant temperature trajectory for the internal combustion engine.

  18. Study on protective facility information price management of civil air defense engineering%人防工程防护设备信息价格管理研究

    Institute of Scientific and Technical Information of China (English)

    张桂萍

    2015-01-01

    论述了人防工程防护设备价格信息管理存在的主要问题,对产生各种问题的原因进行了分析,提出了进一步开放市场、建立全国性的人防工程防护设备信息价网络系统、加强质量监督等对策,以维护防护设备市场的稳定性。%The paper discusses protective facility information price management problems of civil air defense engineering,analyzes various cau-ses,puts forward a series of countermeasures,such as opening market,establishing national civil air defense engineering protecting facility infor-mation price network system,and strengthening quality supervision and so on,with a view to maintain the stability of protective facility market.

  19. Estimation of the in-cylinder air/fuel ratio of an internal combustion engine by the use of pressure sensors

    Energy Technology Data Exchange (ETDEWEB)

    Tunestaal, Per

    2000-03-01

    This thesis investigates the use of cylinder pressure measurements for estimation of the in-cylinder air/fuel ratio in a spark ignited internal combustion engine. An estimation model which uses the net heat release profile for estimating the cylinder air/fuel ratio of a spark ignition engine is developed. The net heat release profile is computed from the cylinder pressure trace and quantifies the conversion of chemical energy of the reactants in the charge into thermal energy. The net heat release profile does not take heat- or mass transfer into account. Cycle-averaged air/fuel ratio estimates over a range of engine speeds and loads show an RMS error of 4.1% compared to measurements in the exhaust. A thermochemical model of the combustion process in an internal combustion engine is developed. It uses a simple chemical combustion reaction, polynominal fits of internal energy as function of temperature, and the first law of thermodynamics to derive a relationship between measured cylinder pressure and the progress of the combustion process. Simplifying assumptions are made to arrive at an equation which relates the net heat release to the cylinder pressure. Two methods for estimating the sensor offset of a cylinder pressure transducer are developed. Both methods fit the pressure data during the pre-combustion phase of the compression stroke to a polytropic curve. The first method assumes a known polytropic exponent, and the other estimates the polytropic exponent. The first method results in a linear least-squares problem, and the second method results in a nonlinear least-squares problem. The nonlinear least-squares problem is solved by separating out the nonlinear dependence and solving the single-variable minimization problem. For this, a finite difference Newton method is derived. Using this method, the cost of solving the nonlinear least-squares problem is only slightly higher than solving the linear least-squares problem. Both methods show good statistical

  20. A study on the characteristics of alternative coolants

    International Nuclear Information System (INIS)

    The role of the coolant in liquid metal fast breeder reactor is very important for reasons of system safety. Recently, it has revealed that lead and lead-bismuth alloy show good safety characteristics as a fast reactor coolant compared to the sodium, such as low chemical activity, high boiling temperature and more negative void coefficient. So many countries take interest in these metals. The objectives of this project are to study the characteristics of heavy liquid metals(lead, lead-bismuth alloy) and to provide valuble information useful for the estimate the possibilities of its as the alternative coolant materials. An intensive research was performed into the global development status, basic properties, safety assurance methods, and direction of research in the futures and so on

  1. A study on the characteristics of alternative coolants

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ji Young; Kim, B. H.; Kim, T. J.; Jeong, K. C.; Choi, Y. D.; Choi, J. H.; Hwang, S. T

    2000-12-01

    The role of the coolant in liquid metal fast breeder reactor is very important for reasons of system safety. Recently, it has revealed that lead and lead-bismuth alloy show good safety characteristics as a fast reactor coolant compared to the sodium, such as low chemical activity, high boiling temperature and more negative void coefficient. So many countries take interest in these metals. The objectives of this project are to study the characteristics of heavy liquid metals(lead, lead-bismuth alloy) and to provide valuble information useful for the estimate the possibilities of its as the alternative coolant materials. An intensive research was performed into the global development status, basic properties, safety assurance methods, and direction of research in the futures and so on.

  2. Influence of coolant motion on structure of hardened steel element

    Directory of Open Access Journals (Sweden)

    A. Kulawik

    2008-08-01

    Full Text Available Presented paper is focused on volumetric hardening process using liquid low melting point metal as a coolant. Effect of convective motion of the coolant on material structure after hardening is investigated. Comparison with results obtained for model neglecting motion of liquid is executed. Mathematical and numerical model based on Finite Element Metod is described. Characteristic Based Split (CBS method is used to uncouple velocities and pressure and finally to solve Navier-Stokes equation. Petrov-Galerkin formulation is employed to stabilize convective term in heat transport equation. Phase transformations model is created on the basis of Johnson-Mehl and Avrami laws. Continuous cooling diagram (CTPc for C45 steel is exploited in presented model of phase transformations. Temporary temperatures, phases participation, thermal and structural strains in hardening element and coolant velocities are shown and discussed.

  3. The auxiliary system design retrofits of the different coolant pump

    International Nuclear Information System (INIS)

    The coolant pump auxiliary systems retrofits are introduced in detail according to the different type of coolant pumps. The retrofit reasons of the chemical and volume control system, component cooling water system, Nuclear Nitrogen Storage and Distribution System, Vent and drain system, etc. are investigated. The most extraordinary change takes place in the chemical and volume control system and cooling water system. The charging flow temperature of re- generative heat exchanger and discharge flow of charging pump will be changed according to the difference coolant pump seal flow distribution. The commercial CFD software Flow master is employed to validate the charging capability. The other auxiliary systems' retrofits are also introduced in the end of this paper. (authors)

  4. Coolant clean-up method in PWR type reactors

    International Nuclear Information System (INIS)

    Purpose: To perform coolant clean-up while climinating the need of replacing boric acid with plant primary coolants and using anionic exchange resins in which the amount of Cl anionic exchange resins as impurities is decreased. Method: OH type anionic exchange resins are previously treated with an aqueous boric acid not containing radioactivity at a place other than the equipment for use (that is desalting tower) into boric acid type anionic ion exchange resins and, thereafter, the boric acid type anionic exchange resins are filled into a desalting tower of the clean-up system to perform primary coolant clean-up. In this case, since the resins can be used directly for the purpose without performing boric acid replacement after charging into the equipment for use, the procedures in the plant being in operation can be saved. (Yoshino, Y.)

  5. Design and development of remotely operated coolant channel cutting machine

    International Nuclear Information System (INIS)

    One of the coolant tubes of Narora Atomic Power Station (NAPS) reactor needs to be removed. To remove a coolant tube, four cutting operations, (liner tube cutting, end-fitting cutting, machining of seal weld of bellow ring and finally coolant tube cutting) are required to be carried out. A remotely operated cutting machine to carry out all these operations has been designed and developed by Central Workshops. This machine is able to cut at the exact location because of numerically controlled axial and radial travel of tool. Only by changing the tool head and tool holder, same machine can be used for various types of cutting/machining operations. This report details the design, manufacture, assembly and testing work done on the machine. (author). 4 figs

  6. Fracture mechanics evaluation for at typical PWR primary coolant pipe

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T. [Kansai Electric Power Company, Osaka (Japan); Shimizu, S.; Ogata, Y. [Mitsubishi Heavy Industries, Ltd., Kobe (Japan)

    1997-04-01

    For the primary coolant piping of PWRs in Japan, cast duplex stainless steel which is excellent in terms of strength, corrosion resistance, and weldability has conventionally been used. The cast duplex stainless steel contains the ferrite phase in the austenite matrix and thermal aging after long term service is known to change its material characteristics. It is considered appropriate to apply the methodology of elastic plastic fracture mechanics for an evaluation of the integrity of the primary coolant piping after thermal aging. Therefore we evaluated the integrity of the primary coolant piping for an initial PWR plant in Japan by means of elastic plastic fracture mechanics. The evaluation results show that the crack will not grow into an unstable fracture and the integrity of the piping will be secured, even when such through wall crack length is assumed to equal the fatigue crack growth length for a service period of up to 60 years.

  7. Integrated Fuel-Coolant Interaction (IFCI 6.0) code

    International Nuclear Information System (INIS)

    The integrated Fuel-Coolant interaction (IFCI) computer code is being developed at Sandia National Laboratories to investigate the fuel-coolant interaction (FCI) problem at large scale using a two-dimensional, four-field hydrodynamic framework and physically based models. IFCI will be capable of treating all major FCI processes in an integrated manner. This document is a product of the effort to generate a stand-alone version of IFCI, IFCI 6.0. The User's Manual describes in detail the hydrodynamic method and physical models used in IFCI 6.0. Appendix A is an input manual, provided for the creation of working decks

  8. Spectrophotometric Procedure for Fast Reactor Advanced Coolant Manufacture Control

    Science.gov (United States)

    Andrienko, O. S.; Egorov, N. B.; Zherin, I. I.; Indyk, D. V.

    2016-01-01

    The paper describes a spectrophotometric procedure for fast reactor advanced coolant manufacture control. The molar absorption coefficient of dimethyllead dibromide with dithizone was defined as equal to 68864 ± 795 l·mole-1·cm-1, limit of detection as equal to 0.583 · 10-6 g/ml. The spectrophotometric procedure application range was found to be equal to 37.88 - 196.3 g. of dimethyllead dibromide in the sample. The procedure was used within the framework of the development of the method of synthesis of the advanced coolant for fast reactors.

  9. Assessment of size aspects in modelling molten fuel coolant interaction.

    OpenAIRE

    Pla Freixa, Patricia

    2004-01-01

    Severe accidents in light water nuclear reactors occur when reactor vessel water inventory decreases and there is no available additional water coolant to be delivered into the core. In general, during an extended severe accident sequence a period exists in which the reactor core, after a partial or total melt down, is poured into the lower plenum that can have some water present. The study of the interaction of the melt fuel with the water is the objective of MFCI (Melt Fuel Coolant Interact...

  10. Impedance calculations for power cables to primary coolant pump motors

    International Nuclear Information System (INIS)

    The LOFT primary system motor generator sets are located in Room B-239 and are connected to the primary coolant pumps by means of a power cable. The calculated average impedance of this cable is 0.005323 ohms per unit resistance and 0.006025 ohms per unit reactance based on 369.6 kVA and 480 volts. The report was written to show the development of power cable parameters that are to be used in the SICLOPS (Simulation of LOFT Reactor Coolant Loop Pumping System) digital computer program as written in LTR 1142-16 and also used in the pump coastdowns for the FSAR Analysis

  11. Choice of coolant in commercial tokamak power plants

    International Nuclear Information System (INIS)

    The STARFIRE design study focused on solid tritium breeder blankets in order to minimize the stored chemical energy. The most suitable coolant candidates with solid tritium breeders are water and helium. This paper presents the results of a comparative study of the two coolants. The study shows clear advantages for the choice of pressurized water for the conditions of the STARFIRE tokamak power plant design. The study also identifies those areas where development is required in order to utilize the potential advantages of helium

  12. Secondary Coolant Management for HANARO (First Half of 2009)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. S.; Jung, H. S.; Park, Y. S.

    2009-11-15

    The water for the secondary cooling system of HANARO research reactor removes heat generated from the reactor core and other facilities using heat exchangers and cooling towers. The quality of the coolant effects the lifetime of the components and the efficiency of heat removal by resulting corrosion, slime, and fouling in the system. So to maintain the quality of the coolant as a optimal condition the periodic sampling and analysis are performed on the several parameter. According to the analysis results countermeasures are implemented. This report describes activities and analysis results during first half of the year 2009.

  13. Feasibility study on naturally safe HTGR (NSHTR) for air ingress accident

    International Nuclear Information System (INIS)

    A new design activity for an advanced reactor, referred to as a naturally safe high temperature gas-cooled reactor (NSHTR), has been launched by authors after the accident at the Fukushima Daiichi Nuclear Power Station. The concept of NSHTR is that the release of radioactive materials is kept at very low level and no harmful effect on people and the environment is ensured by only physical phenomena even in the absence of engineered safety features. At an air ingress accident, possible physical events that lead to the loss or degradation of the confinement function of the fuel-coating layers are the crack of the coatings caused by the explosion of carbon monoxide (CO) produced by the graphite oxidation and failure of the coatings by melting or sublimation caused by core heat up due to the reaction heat of the graphite oxidation. In this study, the CO concentration and the heat generated by graphite oxidation inside the circular tube were evaluated parametrically using a steady-state one-dimensional model to confirm the feasibility of NSHTR at a severe condition of the air ingress accident (i.e., a massive air ingress by simultaneous rupture of two primary pipes). It was confirmed that the CO concentration at the outlet of coolant channel can be maintained below the explosion limit due to the reaction with oxygen in the air, and the reaction heat can be removed with the decay heat by physical phenomena under certain conditions of the coolant channel geometry without any engineered safety features. The results revealed that the design of NSHTR is technically feasible in terms of the suppression of the CO explosion and the heat removal of the reaction heat at the air ingress accident

  14. Adaptive Control Using Fully Online Sequential-Extreme Learning Machine and a Case Study on Engine Air-Fuel Ratio Regulation

    Directory of Open Access Journals (Sweden)

    Pak Kin Wong

    2014-01-01

    Full Text Available Most adaptive neural control schemes are based on stochastic gradient-descent backpropagation (SGBP, which suffers from local minima problem. Although the recently proposed regularized online sequential-extreme learning machine (ReOS-ELM can overcome this issue, it requires a batch of representative initial training data to construct a base model before online learning. The initial data is usually difficult to collect in adaptive control applications. Therefore, this paper proposes an improved version of ReOS-ELM, entitled fully online sequential-extreme learning machine (FOS-ELM. While retaining the advantages of ReOS-ELM, FOS-ELM discards the initial training phase, and hence becomes suitable for adaptive control applications. To demonstrate its effectiveness, FOS-ELM was applied to the adaptive control of engine air-fuel ratio based on a simulated engine model. Besides, controller parameters were also analyzed, in which it is found that large hidden node number with small regularization parameter leads to the best performance. A comparison among FOS-ELM and SGBP was also conducted. The result indicates that FOS-ELM achieves better tracking and convergence performance than SGBP, since FOS-ELM tends to learn the unknown engine model globally whereas SGBP tends to “forget” what it has learnt. This implies that FOS-ELM is more preferable for adaptive control applications.

  15. Transient two-phase two-component flow in NPP with WWER premises during loss-of coolant-accident

    International Nuclear Information System (INIS)

    The work objective was the development of a model describing processes in the premises of a NPP with water cooled reactor within the first second during lost-of-coolant-accident with the main circulation pipeline rupture. Two-phase two-component flow of water-steam-air mixture has been studied. An attempt has been made to obtain a hyperbolic set of partial differential equations in a canonical form suitable for application of the method of charakteristics in any modification. The two-phase two-component critical flow theory is considered as well as the sonic velocity corresponding to the calculated sonic velocity value as a function of the true volumetric gas contant. A calculation example is presented of the pressure history in a 1000 m3 box wherein the NPP with WWER primary circulating loop coolant is flowing (the main circulation pipeline cold branch rupture)

  16. A Mobile Solution to Enhance Training and Execution of Troubleshooting Techniques of the Engine Air Bleed System on Boeing 737

    OpenAIRE

    Rios, Horacio; Gonzalez, Eduardo; Rodriguez, Ciro; Siller, Hector R.; Contero, Manuel

    2013-01-01

    The process of troubleshooting an aircraft engine requires highly skilled and trained personnel who must be able to respond effectively to any circumstance; therefore, new methods of training to accelerate the cognitive processes of technicians must be integrated in the industry. In this matter the Augmented Reality technology represents an innovative tool that can ensure the efficient and correct transfer of knowledge. The numbers of errors during maintenance tasks can be reduced, AR provide...

  17. Automatización de un Secador Convectivo de Aire Caliente para fines de Docencia en Ingeniería de Alimentos Automation of a Convective Hot Air Dryer for Teaching in Food Engineering

    Directory of Open Access Journals (Sweden)

    Jorge A Saavedra

    2008-01-01

    Full Text Available El presente trabajo describe el diseño y montaje de un dispositivo experimental para la automatización de un secador de aire caliente con flujo paralelo en co-corriente para realizar estudios de secado. El desarrollo del trabajo se dividió en dos actividades principales: (i diseño del sistema de automatización y (ii la validación de los datos entregados por el equipo. Se obtuvo un dispositivo capaz de registrar las variables del proceso de secado y de la imagen de la muestra deshidratada en tiempo real, como así mismo transmitir dicha información a través de Internet. Los datos procesados por el sistema automático comparados con experiencias manuales tradicionales (no automatizadas se validaron estadísticamente. Se concluye finalmente que la propuesta es viable, fiable y atractiva para el usuario por lo que facilita el proceso de enseñanza-aprendizaje en un área de especial importancia en Ingeniería de Alimentos.This paper describes the design and installation of an automated experimental device applied to a parallel co-current hot air dryer to perform drying studies in the field of food engineering. The development of this work was divided into two main activities: (i design of the automation system and (ii validation of automatically collected data. A device capable of collecting and registering real time data and images from drying processes, and transmitting them through Internet was obtained. The data processed by the automatic device was statistically validated. It is concluded that the proposed automation device is feasible, reliable and attractive for the users, facilitating the teaching-learning process in an important area of Food Engineering.

  18. Progress in materials, including spallation targets and coolants

    International Nuclear Information System (INIS)

    A summary on R and D activities performed in Europe, partly with the support of the European Commission, to study materials for transmutation systems and their associated technologies is given. Emphasis has been placed on structural materials selection/development, their assessment under representative conditions for spallation target and core, and the impact of the coolant technology on the materials' performance. (authors)

  19. Reactor coolant and associated systems in nuclear power plants

    International Nuclear Information System (INIS)

    This Safety Guide outlines the design requirements for the reactor coolant and associated systems (RCAS) and the features required in order to achieve their safety functions. It covers design considerations for various reactor types and encompasses the safety aspects of the functions of the RCAS both during normal operation and following postulated initiating events, and to some extent also for decommissioning

  20. Low temperature overpressure analysis of reactor coolant system

    International Nuclear Information System (INIS)

    The low temperature overpressure of reactor coolant system was analyzed for Pakistan Chashma Nuclear Power Plant Unit-2 by using the code Relap5/Mod3. The result of RCS peaking pressure shows that the RCS would not be over pressurized under low temperature transient. (authors)

  1. Thermal explosions resulting from fuel-coolant interactions

    International Nuclear Information System (INIS)

    High-speed photographic data and pressure traces of thermal explosions from the contact of single drops of ion oxide with water were analyzed according to models describing underwater chemical explosion and cavitation bubbles. The objective was to develop a simple method for analyzing the microscale hydrodynamics of fuel-coolant interactions (FCI). For a given external pressure and liquid density essentially all the features of the radial motion of the explosion bubble, including the total energy release, are uniquely determined by a single parameter - the bubble period. Nearly all of the heat transfer from fuel to coolant occurs during the 10-5 to 10-4 sec timespan of coolant vapor film collapse during which the fuel fragments. The features of the resulting explosion bubble are not significantly affected by the degree of heat transfer from vapor to coolant liquid and the bubble can be modeled as an empty cavity. The method developed during this study should facilitate investigations on FCI by simplifying the analyses of thermal explosion data. Further attention can be given to experiments on the effects of fuel parameters, e.g., surface tension and viscosity, on fragmentation, heat transfer, and explosive yield

  2. Corrosion of structural materials by lead based reactor coolants

    International Nuclear Information System (INIS)

    Advanced nuclear reactor design has, in recent years, focused increasingly on the use of heavy-liquid-metal coolants, such as lead and lead-bismuth eutectic. Similarly, programs on accelerator-based transmutation systems have also considered the use of such coolants. Russian experience with heavy-metal coolants for nuclear reactors has lent credence to the validity of this approach. Of significant concern is the compatibility of structural materials with these coolants. We have used a thermal convection-based test method to allow exposure of candidate materials to molten lead and lead-bismuth flowing under a temperature gradient. The gradient was deemed essential in evaluating the behavior of the test materials in that should preferential dissolution of components of the test material occur we would expect dissolution in the hotter regions and deposition in the colder regions, thus promoting material transport. Results from the interactions of a Si-rich mild steel alloy, AISI S5, and a ferritic-martensitic stainless steel, HT-9, with the molten lead-bismuth are presented. (author)

  3. Verification of computer code for calculation of coolant radiolysis in the VVER reactor core with regard for boiling in its upper part

    International Nuclear Information System (INIS)

    Code Bora for WWER coolant radiolysis calculation considering single jets boiling in the reactor core top part is developed on the basis of computer codes MOPABA-H2 (radiolysis of aqueous solutions) and SteamRad (radiolysis of vapor). Physico-chemical processes taking place in boiling core coolant are complex and diversified. Still, for the solution of certain problems their simulation can be simplified. The approach of reasonable simplification was used for development of code Bora: mathematical model assumed is purposed for simulation of phenomena only in the area of interest; the number of simulated chemical reactions and particles shall be reasonably minimum; complexity of interphase mass transfer calculation procedure shall be adequate to actually available accuracy of modeling. The analysis of new experimental initial yields of water radiolysis products data and kinetic parameters of elementary chemical reactions with their participation has been carried out. Some changes have been introduced in the mechanism of liquid water and aqueous solutions of ammonia radiolysis have been significantly revised on the basis of this analysis. Examples of the calculations provided for code Bora verification are presented. Despite of very simple simulation of interphase mass transfer, Bora allows to obtain average chemical composition of two-phase coolant at BWR core outlet with the accuracy sufficient for engineering calculations. The report also presents the results of two-phase coolant chemical composition test calculation for reactor core top part coolant boiling in pressurized water reactor. (author)

  4. Research work on coolant technology in China

    International Nuclear Information System (INIS)

    In the Peoples Republic of China, research is being carried out in order to provide water chemistry data for design, construction and operation of small and medium size NPs in China. The nuclear program in China has some national features: the projects to study the water chemistry aspects reflects the requirements of China's NPS engineering and design. The structural materials made in China such as fuel cladding materials, steam generator heat transfer tubes and ion exchange reins are not the same as those made in other countries. We have learnt from other countries and we have actively adopted their successful experiences in all aspects, besides, we have carried out a series of experiments on water chemistry problems concerning design and operation of NPs in China. The preparation of nuclear grade resins, control of boron and lithium in dynamic water loop, determination of impurities (O2, Cl-, F- and other metallic species) in primary circuit and monitoring on-line the thermal breakdown of resins in high temperature, high pressure water loop, study of decontamination processes and study on Zircaloy and steam generator heat transfer tubes corrosion are some of the studies being carried out in the field of water chemistry. The project 'investigation on water chemistry of primary circuit for PWR unit' is essentially a fundamental study on water chemistry which is related to the three tasks of ''WACOLIN''. (author)

  5. Methods for incorporating effects of LWR coolant environment into ASME code fatigue evaluations.

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, O. K.

    1999-04-15

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Appendix I to Section HI of the Code specifies design fatigue curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Recent test data illustrate potentially significant effects of LWR environments on the fatigue resistance of carbon and low-alloy steels and austenitic stainless steels (SSs). Under certain loading and environmental conditions, fatigue lives of carbon and low-alloy steels can be a factor of {approx}70 lower in an LWR environment than in air. These results raise the issue of whether the design fatigue curves in Section III are appropriate for the intended purpose. This paper presents the two methods that have been proposed for incorporating the effects of LWR coolant environments into the ASME Code fatigue evaluations. The mechanisms of fatigue crack initiation in carbon and low-alloy steels and austenitic SSs in LWR environments are discussed.

  6. Methods for incorporating effects of LWR coolant environment into ASME code fatigue evaluations

    International Nuclear Information System (INIS)

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Appendix I to Section HI of the Code specifies design fatigue curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Recent test data illustrate potentially significant effects of LWR environments on the fatigue resistance of carbon and low-alloy steels and austenitic stainless steels (SSs). Under certain loading and environmental conditions, fatigue lives of carbon and low-alloy steels can be a factor of ∼70 lower in an LWR environment than in air. These results raise the issue of whether the design fatigue curves in Section III are appropriate for the intended purpose. This paper presents the two methods that have been proposed for incorporating the effects of LWR coolant environments into the ASME Code fatigue evaluations. The mechanisms of fatigue crack initiation in carbon and low-alloy steels and austenitic SSs in LWR environments are discussed

  7. Effect of reactor coolant radioactivity upon configuration feasibility for a nuclear electric propulsion vehicle

    Science.gov (United States)

    Soffer, L.; Wright, G. N.

    1973-01-01

    A preliminary shielding analysis was carried out for a conceptual nuclear electric propulsion vehicle designed to transport payloads from low earth orbit to synchronous orbit. The vehicle employed a thermionic nuclear reactor operating at 1575 kilowatts and generated 120 kilowatts of electricity for a round-trip mission time of 2000 hours. Propulsion was via axially directed ion engines employing 3300 pounds of mercury as a propellant. The vehicle configuration permitted a reactor shadow shield geometry using LiH and the mercury propellant for shielding. However, much of the radioactive NaK reactor coolant was unshielded and in close proximity to the power conditioning electronics. An estimate of the radioactivity of the NaK coolant was made and its unshielded dose rate to the power conditioning equipment calculated. It was found that the activated NaK contributed about three-fourths of the gamma dose constraint. The NaK dose was considered a sufficiently high fraction of the allowable gamma dose to necessitate modifications in configuration.

  8. Organic coolants and their applications to fusion reactors

    International Nuclear Information System (INIS)

    Organic coolants offer a unique set of characteristics for fusion applications. Their advantages include high-temperature (670 K or 400 degrees C) but low-pressure (2 MPa) operation, limited reactivity with lithium and lithium-lead, reduced corrosion and activation, good heat-transfer capabilities, no magnetohydrodynamic (MHD) effects, and an operating temperature range that extends to room temperature. The major disadvantages are decomposition and flammability. However, organic coolants have been extensively studied in Canada, including nineteen years with an operating 60-MW organic-cooled reactor. Proper attention to design and coolant chemistry controlled these potential problems to acceptable levels. This experience provides an extensive data base for design under fusion conditions. The organic fluid characteristics are described in sufficient detail to allow fusion system designers to evaluate organic coolants for specific applications. To illustrate and assess the potential applications, analyses are presented for organic-cooled blankets, first walls, high heat flux components and thermal power cycles. Designs are identified that take advantage of organic coolant features, yet have fluid decomposition related costs that are a small fraction of the overall cost of electricity. For example, organic-cooled first walls make lithium/ferritic steel blankets possible in high-field, high-surface-heat-flux tokamaks, and organic-cooled limiters (up to about 8 MW/m2 surface heating) are a safer alternative to water cooling for liquid metal blanket concept. Organics can also be used in intermediate heat exchanger loops to provide efficient heat transfer with low reactivity and a large tritium barrier. 55 refs

  9. Physical Model and Calculation Code for Fuel Coolant Interactions

    International Nuclear Information System (INIS)

    The base of the physical model of the FCI in discussion are the shock tube experiments performed with UO2 and Na. The experiments demonstrated that the process of 'vapour explosion' in constrained configurations consists of successive cycles. According to the experimental results, the interaction model described here divides each cycle into three phases: Fuel-Coolant-Contact (Phase A), Ejection and reentry of the coolant (Phase B), Impact and Fragmentation (Phase C). The results of some calculations, performed for different values of the system pressure resp. of the coolant bulk temperature, are compiled in plots displaying the series of successive ejection events of an interaction; the plots represent the ejection height and the corresponding pressure in the vapour volume versus time. The pressure peaks mark the impact pressure pulse resp. the vapour pressure immediately after contact, which-ever is greater; the acoustic pressure peak of Phase A has not been plotted. The third and the following cycles reveal the oscillating reentry behaviour. A physical model has been proposed to describe fuel coolant interactions in shock-tube geometry. The corresponding code is presently in an advanced state of development. A principal feature, of the code is the consistent application of the Fourier-equation throughout the whole interaction process; this reveals some peculiarities which do not become evident otherwise. The two dimensional representation of the coolant flow provides the basis for a fragmentation mechanism, thus relieving from the necessity to introduce the fragmentation as an input parameter. These features may indicate a step towards a more realistic comprehension of the subject

  10. Development of a New Type of Green Switch Air Entraining Agent for Wet-Mix Shotcrete and Its Engineering Application

    Directory of Open Access Journals (Sweden)

    Guoming Liu

    2016-01-01

    Full Text Available Air entraining agent (AEA can bring a lot of microbubbles into fresh concrete for improving its fluidity; however, high fluidity has adverse effect on the shootability of wet-mix shotcrete. In order to solve the contradictory issue, the paper developed a new type of green switch air entraining agent (GSAE that can improve both the pumpability and shootability. The single-admixture and combination tests containing foaming ability and surface tension were performed with Deer agitator and automatic tension meter. The new AEA was developed with two constituents A and B. A was prepared with Sapindus mukorossi(S-1, dodecyl trimethyl ammonium chloride(1231, and polyacrylamide. B was prepared with lauryl sodium sulfate (K12 and silicone oil. The mass mix proportion was S-1 : 1231 : polyacrylamide : K12 : silicone oil = 1 : 0.33 : 0.2 : 0.33 : 0.47. The application method of GSAE proposed that A was premixed with fresh concrete and then B was added at nozzle. Experimental investigation showed that the optimal mixing amount of GSAE was 0.1%–0.2% relative to cement. All performance measured of wet-mix shotcrete with 0.12% GSAE met the first-grade product requirements of the China National Standard. Compared with the conventional type of AEA, the proposed GSAE is capable of effectively improving pumpability and shootability.

  11. Numerical study with experimental comparison of pressure waves in the air intake system of an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Falcao, Carlos E.G.; Vielmo, Horacio A. [Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Mechanical Engineering Dept.], E-mails: vielmoh@mecanica.ufrgs.br; Hanriot, Sergio M. [Pontifical Catholic University of Minas Gerais (PUC-Minas), Belo Horizonte, MG (Brazil). Mechanical Engineering Dept.], E-mail: hanriot@pucminas.br

    2010-07-01

    The work investigates the pressure waves behavior in the intake system of an internal combustion engine. For the purpose of examining this problem, it was chosen an experimental study in order to validate the results of the present simulation. At the literature there are several experimental studies, and some numerical simulations, but the most of the numerical studies treat the problem only in one dimension in practical problems, or two dimensions in specific problems. Using a CFD code it is possible to analyze more complex systems, including tridimensional effects. The pulsating phenomenon is originated from the periodic movement of the intake valve, and produces waves that propagate within the system. The intake system studied was composed by a straight pipe connected to a 1000 cc engine with a single operating cylinder. The experiments were carried out in a flow bench. In the present work, the governing equations was discretized by Finite Volumes Method with an explicit formulation, and the time integration was made using the multi-stage Runge-Kutta time stepping scheme. The solution is independent of mesh or time step. The numerical analysis presents a good agreement with the experimental results. (author)

  12. 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.

  13. Loss-of-coolant accident analysis of the Savannah River new production reactor design

    International Nuclear Information System (INIS)

    This document contains the loss-of-coolant accident analysis of the representative design for the Savannah River heavy water new production reactor. Included in this document are descriptions of the primary system, reactor vessel, and loss-of-coolant accident computer input models, the results of the cold leg and hot leg loss-of-coolant accident analyses, and the results of sensitivity calculations for the cold leg loss-of-coolant accident. 5 refs., 50 figs., 4 tabs

  14. Engineering Schottky Contacts in Open-Air Fabricated Heterojunction Solar Cells to Enable High Performance and Ohmic Charge Transport

    OpenAIRE

    Hoye, Robert L.Z.; Heffernan, Shane; Ievskaya, Yulia; Sadhanala, Aditya; Flewitt, Andrew; Friend, Richard H.; MacManus-Driscoll, Judith L; Musselman, Kevin P.

    2014-01-01

    The efficiencies of open-air processed Cu2O/Zn1–x Mg x O heterojunction solar cells are doubled by reducing the effect of the Schottky barrier between Zn1–x Mg x O and the indium tin oxide (ITO) top contact. By depositing Zn1–x Mg x O with a long band-tail, charge flows through the Zn1–x Mg x O/ITO Schottky barrier without rectification by hopping between the sub-bandgap states. High current densities are obtained by controlling the Zn1–x Mg x O thickness to ensure that the Schottky barrier i...

  15. Air Pollution and Industry.

    Science.gov (United States)

    Ross, R. D., Ed.

    This book is an authoritative reference and practical guide designed to help the plant engineer identify and solve industrial air pollution problems in order to be able to meet current air pollution regulations. Prepared under the editorial supervision of an experienced chemical engineer, with each chapter contributed by an expert in his field,…

  16. Failure probability of PWR reactor coolant loop piping. [Double-ended guillotine break

    Energy Technology Data Exchange (ETDEWEB)

    Lo, T.; Woo, H.H.; Holman, G.S.; Chou, C.K.

    1984-02-01

    This paper describes the results of assessments performed on the PWR coolant loop piping of Westinghouse and Combustion Engineering plants. For direct double-ended guillotine break (DEGB), consideration was given to crack existence probability, initial crack size distribution, hydrostatic proof test, preservice inspection, leak detection probability, crack growth characteristics, and failure criteria based on the net section stress failure and tearing modulus stability concept. For indirect DEGB, fragilities of major component supports were estimated. The system level fragility was then calculated based on the Boolean expression involving these fragilities. Indirect DEGB due to seismic effects was calculated by convolving the system level fragility and the seismic hazard curve. The results indicate that the probability of occurrence of both direct and indirect DEGB is extremely small, thus, postulation of DEGB in design should be eliminated and replaced by more realistic criteria.

  17. Thermohydraulic investigation in justification of fast reactor core with liquid metal coolants

    International Nuclear Information System (INIS)

    Thermohydraulic analysis of fast reactor (FR) cores is a component of the complex of interrelated problems on FR parameters justification. These problems concern reactor physics, thermal mechanics, failure theory and other components. Thermohydraulic analysis includes determination of temperature mode of core elements, hydraulic characteristics of fuel assemblies, their nominal and maximal capacitance. The present state of the art of problem-oriented, pilot and applied thermohydraulic studies of FR cores with liquid metal coolants (LMC) is under consideration. The experimental and calculating data on thermal hydraulics of LMC reactors gathered in the Institute for Physics and Power Engineering is analyzed and generalized when comparing different calculating procedures, problem solution techniques. The methods and codes of numerical simulation of thermohydraulic processes in LMC FR core are considered. The problems and aims of further investigations are formulated

  18. MATLAB/Simulink Framework for Modeling Complex Coolant Flow Configurations of Advanced Automotive Thermal Management Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Titov, Eugene; Lustbader, Jason; Leighton, Daniel; Kiss, Tibor

    2016-03-22

    The National Renewable Energy Laboratory's (NREL's) CoolSim MATLAB/Simulink modeling framework was extended by including a newly developed coolant loop solution method aimed at reducing the simulation effort for arbitrarily complex thermal management systems. The new approach does not require the user to identify specific coolant loops and their flow. The user only needs to connect the fluid network elements in a manner consistent with the desired schematic. Using the new solution method, a model of NREL's advanced combined coolant loop system for electric vehicles was created that reflected the test system architecture. This system was built using components provided by the MAHLE Group and included both air conditioning and heat pump modes. Validation with test bench data and verification with the previous solution method were performed for 10 operating points spanning a range of ambient temperatures between -2 degrees C and 43 degrees C. The largest root mean square difference between pressure, temperature, energy and mass flow rate data and simulation results was less than 7%.

  19. An introduction to the engineering of fast nuclear reactors

    CERN Document Server

    Judd, Anthony M

    2014-01-01

    An invaluable resource for both graduate-level engineering students and practising nuclear engineers who want to expand their knowledge of fast nuclear reactors, the reactors of the future! This book is a concise yet comprehensive introduction to all aspects of fast reactor engineering. It covers topics including neutron physics; neutron flux spectra; flux distribution; Doppler and coolant temperature coefficients; the performance of ceramic and metal fuels under irradiation, structural changes, and fission-product migration; the effects of irradiation and corrosion on structural materials, irradiation swelling; heat transfer in the reactor core and its effect on core design; coolants including sodium and lead-bismuth alloy; coolant circuits; pumps; heat exchangers and steam generators; and plant control. The book includes new discussions on lead-alloy and gas coolants, metal fuel, the use of reactors to consume radioactive waste, and accelerator-driven subcritical systems.

  20. Helium chemistry in high temperature gas cooled reactors - chemical impurity behaviour in the secondary helium coolant of the HTTR

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency (JAEA) constructed High Temperature Engineering Test Reactor (HTTR) in order to establish and upgrade the technology basis for the high-temperature gas-cooled reactors (HTGRs) and to develop the technology for high-temperature heat applications. The HTTR attained its maximum reactor-outlet coolant temperature of 950 Degrees C in 2004. The intermediate heat exchanger (IHX), which is a helium-helium heat exchanger and installed to the HTTR primary cooling system, is planned to be utilized for the hydrogen production system in the near future. Secondary coolant helium receives heat from primary helium at the heat exchanger pipes made by high-temperature super alloy Hastelloy XR. The secondary pressurized water cooler, which is a helium-water heat exchanger and installed to the secondary cooling system, will replace to the hydrogen production system. The thermochemical water-splitting IS process is a progressive candidate for the hydrogen production system. Chemistry control is necessary in order to avoid oxidation of core graphite and corrosions of high-temperature material of Hastelloy XR, e.g. carbon deposits, carburising and decarburising. The chemical impurity is reduced and monitored by helium purification system and helium sampling system installed primary and secondary helium cooling system, respectively. This report describes impurity behaviour of secondary coolant during the initial 950 operation of the HTTR

  1. Channel-type nuclear reactor with a boiling coolant

    International Nuclear Information System (INIS)

    The invention is aimed at increasing the channel-type reactor safety, in particular, RBMK-type reactors, during accidents resulting in the coolant circulation discontinuation. The reactor core is assembled of vertial technological channels connected in parallel between distributing group collectors and drum-separator. Each technological channel contains a high pressure tube, a fuel assembly with fuel elements and a storage vessel located above the fuel assembly which is filled with water at saturation temperature in the normal operation regime. After dehydration of channels in the course of accident the boiling water from storage vessel is ejected into them. So the device described allows one to reduce the fuel element can temperature in the course of accidents connected with the coolant circulation discontinuation and so to increase the plant safety level

  2. Nonlinear dynamic analysis of nuclear reactor primary coolant systems

    International Nuclear Information System (INIS)

    The ADINA computer code is utilized to perform mechanical response analysis of pressurized reactor primary coolant systems subjected to postulated loss-of-coolant accident (LOCA) loadings. Specifically, three plant analyses are performed utilizing the geometric and material nonlinear analysis capabilities of ADINA. Each reactor system finite element model represents the reactor vessel and internals, piping, major components, and component supports in a single coupled model. Material and geometric nonlinear capabilities of the beam and truss elements are employed in the formulation of each finite element model. Loadings applied to each plant for LOCA dynamic analysis include steady-state pressure, dead weight, strain energy release, transient piping hydraulic forces, and reactor vessel cavity pressurization. Representative results are presented with some suggestions for consideration in future ADINA code development

  3. LMFRs R and D knowledge preservation: Sodium coolant (viewgraphs)

    International Nuclear Information System (INIS)

    Within the principles of the study it was demanded to select the major documents to keep the knowledge on sodium for the next thirty years. In order to do so, it was necessary ro have a small presentation text, and a limited number of references. This study must be performed in a limited time. Experts for different item were selected among CEA, EDF and Framatome staff. The main item treated were: general knowledge on sodium, primary sodium, secondary sodium Experimental feedback from Phenix and Superphenix, Argon cover gas, future coolants compared to sodium, books and general conferences on sodium. The selection on sodium coolant is ready for the future: the knowledge preservation is on the way, but it is considered as very convenient for the present as well

  4. Primary coolant pump measurement for ICC trend analysis

    International Nuclear Information System (INIS)

    Reactor coolant pump motor power and temperature measurements are used by Babcock and Wilcox (BandW) plant owners to calculate void fraction for trending ICC conditions while the pumps are running. This new measurement technology satisfies NUREG 0737, Item II.F.2, ''. . . licensees shall provide . . . additional instrumentation . . . to supplement existing instrumentation in order to provide a unambiguous, easy-to-interpret indication of inadequate core cooling.'' System accuracy, capability, and limitations are compared to measurement requirements using small break test data and full scale plant analytical studies. Small break experimental data shows that ICC void fraction calculations are conservative compared to gamma densitometer void fraction measurements in the pipe just upstream of the pumps and liquid level conductivity probes in the reactor vessel. Analytical studies verify that a measure of void fraction at the pumps is conservative relative to the desired coolant inventory trend conditions in the reactor vessel

  5. Primary coolant pump measurement for ICC trend analysis

    International Nuclear Information System (INIS)

    Reactor coolant pump motor power and temperature measurements are used by Babcock and Wilcock (B and W) plant owners to calculate void fraction for trending ICC conditions while the pumps are running. This new measurement technology satisfies NUREG 0737, Item II.F.2, ''...licensees shall provide...additional instrumentation...to supplement existing instrumentation in order to provide a unambiguous, easy-to-interpret indication of inadequate core cooling. System accuracy, capability, and limitations are compared to measurement requirements using small break test data and full scale plant analytical studies. Small break experimental data shows that ICC void fraction calculations are conservative compared to gamma densitometer void fraction measurements in the pipe just upstream of the pumps and liquid level conductivity probes in the reactor vessel. Analytical studies verify that a measure of void fraction at the pumps is conservative relative to the desired coolant inventory trend conditions in the reactor vessel

  6. Experimental study into stratified coolant flow in power plant elements

    International Nuclear Information System (INIS)

    The article presents the results of investigations into temperature field and coolant flow structures using the models of mixing chambers, pipelines, annular gaps of vessel-type reactors under stationary and dynamic operation conditions. The results of experimental investigation of coolant temperature stratification using the models of the FBR upper mixing chamber, pipeline and annular gap of WWER-type reactor are given. Frude critical number is determined for occurrence of temperature stratification in pipelines, and dependences are derived for calculating the height of cold liquid jet penetration in a warmer medium and hot liquid wedge length in pipelines. The investigation results show that stratification changes drastically the dynamics and structure of thermohydraulic processes. Time and space scales of different types of secondary flows, their stability are related to averaged flow characteristics and flow microstructure as well. 5 refs.; 6 figs

  7. Nuclear reactor coolant pump impeller/shaft assembly

    International Nuclear Information System (INIS)

    A pump is described comprising: (a) a casing having an inlet and an outlet in fluid communication for circulating fluid coolant through the pump; (b) a shaft positioned in the casing; (c) an impeller nut connected to the shaft; (d) a lockbolt fixedly connecting the impeller nut relative to the shaft; (e) passageway means with first and second ends for directing fluid from the lockbolt to the shaft; (f) first conduit means formed in the impeller nut in fluid communication with the first end of the passageway means and the inlet of the casing; and (g) second conduit means formed in the impeller nut in fluid communication with the second end of the passageway means and the outlet of the casing. A portion of the fluid coolant circulating through the inlet of the casing is pumped through the first conduit means, through the passageway means, out the second conduit means and into the outlet of the casing

  8. Fuel cladding interaction with water coolant in power reactors

    International Nuclear Information System (INIS)

    Water coolant chemistry and corrosion processes are important factors in reliable operation of NPP's, as at elevated temperatures water is aggressive towards structural materials. Water regimes for commercial Pressurized Water Reactors and Boiling Water Reactors were developed and proved to be satisfactory. Nevertheless, studies of operation experience continue and an amount of new Research and Development work is being conducted for further improvements of technology and better understanding of the physicochemical nature of those processes. In this report information is presented on the IAEA programme on fuel element cladding interaction with water coolant. Some results of this survey and recommendations made by the group of consultants who participated in this work are given as well as recommendations for continuation of this study. Separate abstracts were prepared for 6 papers of this report

  9. Power release monitoring in the WWER by the coolant activation

    International Nuclear Information System (INIS)

    A possibility to use a systeme based on detecting the 16N activity in a primary coolant circuit and designed for measuring the coolant flow rate, for determinine the power release distribution in the WWER core is studied. The measurements were carried out at the first unit of the Armyanskaya NPP using transducers with Geiger-Mueller Counters as the main elements. On the basis of the analysis of the obtained results and their comparison with the results of measurements ausing the thermal balance method and dta calculated according to the BIPR-FN computer code the conclusion is made on compatibility of the above radiometric technique for monitoring the power release in different WWER core areas. The radiation method accuracy is higher than that of the thermal balance method and it to a less degree depends on the reactor power level

  10. Radiological engineering evaluation of the delay time line air scrubber located at the Clinton P. Anderson Meson Physics Facility (LAMPF)

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the effects of the addition of an air scrubber to an already existing delay line and whether it would scrub 11CO2. There were three main objectives of this study. The first objective was to determine the scrubbing efficiency of the scrubber. The scrubbing efficiency was then used to predict the dose rates in the scrubber area and compare those values with measurements from radiological surveys. The third objective was to determine if the shield blocks were effective in reducing the dose rates in the scrubber area. The activities were measured before and during scrubber operation and this information was used to calculate the scrubbing efficiency and the efficiency of 11CO2 removal was determined to be around 50%. Microshield was then used to predict dose rates and compared those values with measurements from radiological surveys. This was also used to determine the that the shield blocks around the scrubber were effective in reducing the dose rates from the radiation field produced by the radionuclides in the scrubber

  11. Application of damage function analysis to reactor coolant circuits

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, D.D. [Center for Electrochemical Science and Technology, Pennsylvania State Univ., University Park, PA (United States)

    2002-07-01

    The application of deterministic models for simulating stress corrosion cracking phenomena in Boiling Water Reactor primary coolant circuits is described. The first generation code, DAMAGE-PREDICTOR, has been used to model the radiolysis of the coolant, to estimate the electrochemical corrosion potential (ECP), and to calculate the crack growth rate (CGR) at fixed state points during reactor operation in about a dozen plants worldwide. This code has been validated in ''double-blind'' comparisons between the calculated and measured hydrogen concentration, oxygen concentration, and ECP in the recirculation system of the Leibstadt BWR in Switzerland, as well as through less formal comparisons with data from other plants. Second generation codes have now been developed, including REMAIN for simulating BWRs with internal coolant pumps and the ALERT series for modeling reactors with external pumps. One of this series, ALERT, yields the integrated damage function (IDF), which is the crack length versus time, on a component-by-component basis for a specified future operating scenario. This code therefore allows one to explore proposed future operating protocols, with the objective of identifying those that are most cost-effective and which minimizes the risk of failure of components in the coolant circuit by stress corrosion cracking. The application of this code is illustrated by exploring the benefits of partial hydrogen water chemistry (HWC) for an actual reactor, in which hydrogen is added to the feedwater over only limited periods during operation. The simulations show that the benefits, in terms of reduction in the IDFs for various components, are sensitive to when HWC was initiated in the plant life and to the length of time over which it is applied. (author)

  12. Experimental investigations of thermal interaction between corium and coolants

    Science.gov (United States)

    Zagorul'ko, Yu. I.; Zhmurin, V. G.; Volov, A. N.; Kovalev, Yu. P.

    2008-03-01

    We present a generalized analysis of the experimental results from investigations of thermal interaction in corium simulators (melts of thermite mixtures U + Mo3 and Zr + Fe2O3)-coolant (Na and H2O) systems. We also present the results from experimental assessments of the kinematic characteristics pertinent to the displacement of materials during the thermal interaction process and the coefficients for conversion of the corium thermal energy into mechanical work.

  13. Application of damage function analysis to reactor coolant circuits

    International Nuclear Information System (INIS)

    The application of deterministic models for simulating stress corrosion cracking phenomena in Boiling Water Reactor primary coolant circuits is described. The first generation code, DAMAGE-PREDICTOR, has been used to model the radiolysis of the coolant, to estimate the electrochemical corrosion potential (ECP), and to calculate the crack growth rate (CGR) at fixed state points during reactor operation in about a dozen plants worldwide. This code has been validated in ''double-blind'' comparisons between the calculated and measured hydrogen concentration, oxygen concentration, and ECP in the recirculation system of the Leibstadt BWR in Switzerland, as well as through less formal comparisons with data from other plants. Second generation codes have now been developed, including REMAIN for simulating BWRs with internal coolant pumps and the ALERT series for modeling reactors with external pumps. One of this series, ALERT, yields the integrated damage function (IDF), which is the crack length versus time, on a component-by-component basis for a specified future operating scenario. This code therefore allows one to explore proposed future operating protocols, with the objective of identifying those that are most cost-effective and which minimizes the risk of failure of components in the coolant circuit by stress corrosion cracking. The application of this code is illustrated by exploring the benefits of partial hydrogen water chemistry (HWC) for an actual reactor, in which hydrogen is added to the feedwater over only limited periods during operation. The simulations show that the benefits, in terms of reduction in the IDFs for various components, are sensitive to when HWC was initiated in the plant life and to the length of time over which it is applied. (author)

  14. Inside story: inspecting RCP [reactor coolant pump] impellers in situ

    International Nuclear Information System (INIS)

    Using a specially developed robot, Pipe Walker, R Brooks Associates, Inc (Brooks) performed ground-breaking visual inspections of the four reactor coolant pump impellers at unit 1 of the Three Mile Island (TMI) plant. This is the first time that inspections of this type have been performed without any disassembly or removal of the pumps, resulting in considerable savings of outage time and cost. (Author)

  15. Coolant chemistry of the advanced carbon dioxide cooled reactor

    International Nuclear Information System (INIS)

    The large scale production of electricity by uranium fission has been achieved in the United Kingdom exclusively by reactors which are gas cooled and moderated by graphite. In this way the use of uranium with close to the natural isotopic content was possible. Once the choice of graphite as moderator had been made then the selection of a suitable gas to transport heat from the core to the steam generating equipment was limited and, in fact, only two have been identified as having suitable chemical and nuclear properties, namely helium and carbon dioxide. The first of these has the disadvantage of being expensive but has a high heat transfer capability and is fundamentally inert, its reactivity being controlled entirely by the level of impurities such as hydrogen and water. With the closure of the OECD Dragon High Temperature Reactor Project interest in helium cooling for nuclear plant has faded in the UK. The alternative coolant, carbon dioxide, which is cheap but chemically reactive is used in the first generation Magnox power stations and in the Commercial Advanced Gas Cooled Reactor (CAGR) design. In the more highly rated CAGR design the fuel consists of enriched uranium in the form of dioxide encased in stainless steel; the gas outlet temperature of the core is increased to around 6000C. The purpose of this paper is to provide an insight into the current thinking about the nature of the complex chemistry associated with the CAGR coolant and how this chemistry influences the rate of deposition onto the fuel pin surfaces and the rate of graphite moderator oxidation. The application of these ideas to the prediction of the behaviour of a CAGR core with particular reference to the calculation of coolant composition within the porous moderator structure at points remote from the surface, is outlined and the use of all this information to define a satisfactory range of coolant composition is also described

  16. Determining water chemistry conditions in nuclear reactor coolants

    International Nuclear Information System (INIS)

    The chemistry of the process and coolant systems in water-cooled nuclear reactors is tightly controlled to minimise material degradation and, for some systems, to regulate reactor power. Tight control entails monitoring the systems and making appropriate adjustments. Online monitoring can be utilised where instruments are available but otherwise samples must be taken and measurements made offline. This paper reviews the current technologies for monitoring and sampling. (author)

  17. The benefits of zinc addition to primary side coolant

    International Nuclear Information System (INIS)

    The addition of soluble zinc to simulated CANDU PHWR primary coolant substantially reduced corrosion rates and corrosion product release rates for carbon steel and stainless steel. Soluble zinc addition reduced the affinity of carbon steel for Co-60 by a factor of 3 to 5, and reduced the affinity of 410 SS for Co-60 by a factor of 60. Decontamination benefits were seen for 410 SS exposed to zinc. (authors). 9 figs., 6 refs

  18. Attempt of lean burn of a 4 cycle gasoline engine by the aid of low pressure air assisted in-cylinder injection; Tonai kuki nenryo funsha ni yoru lean burn no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, S.; Kondo, M.; Sekiya, Y.; Murayama, T. [Hokkaido Automotive Engineering College, Hokkaido (Japan)

    1997-10-01

    Comparable performance and exhaust emission with conventional carburetor was obtained by a low Pressure air assisted in-cylinder injection system. And lean burn of idling and light load operation till A/F=70 was realized by installing a spark Plug and a reed type injection nozzle in a divided combustion chambaer of a 4 cycle gasoline engine. 2 refs., 10 figs.

  19. Corrosion fatigue studies on F82H mod. martensitic steel in reducing water coolant environments

    Energy Technology Data Exchange (ETDEWEB)

    Maday, M.F.; Masci, A. [ENEA, Casaccia (Italy). Centro Ricerche Energia

    1998-03-01

    Load-controlled low cycle fatigue tests have been carried out on F82H martensitic steel in 240degC oxygen-free water with and without dissolved hydrogen, in order to simulate realistic coolant boundary conditions to be approached in DEMO. It was found that water independently of its hydrogen content, determined the same fatigue life reduction compared to the base-line air results. Water cracks exhibited in their first propagation stages similar fracture morphologies which were completely missing on the air cracks, and were attributed to the action of an environment related component. Lowering frequency gave rise to an increase in F82H fatigue lifetimes without any change in cracking mode in air, and to fatigue life reduction by microvoid coalescence alone in water. The data were discussed in terms of (i) frequency dependent concurrent processes for crack initiation and (ii) frequency-dependent competitive mechanisms for crack propagation induced by cathodic hydrogen from F82H corrosion. (author)

  20. Analysis of fuel-coolant quenching phenomena by COMETA code

    International Nuclear Information System (INIS)

    Severe accidents in light water nuclear reactors occur when reactor vessel water inventory decreases and there is no available additional water coolant to be delivered into the core. In general during an extended severe accident sequence a period exists in which the reactor core, after a partial or total melt down, is poured into the lower plenum that can have some water present. The study of the interaction of the melt fuel with the water is the objective of MFCI (Melt Fuel Coolant Interaction) activities. MFCI phenomena are of great safety interest for two main reasons: a) as precursory to possible steam explosions; b) as initial conditions for the lower plenum debris coolability problem. For the first reason, it is important to determine the melt-coolant mixture conditions in order to evaluate if an explosion is conceivable or not. For the second one, it is important to check which is the physical state of the molten fuel when reaching the lower plenum bottom since it can seriously affect the possibility of coolability and vessel failure. In order to study the phenomenological behaviour of the thermal hydraulic system, our work has been focused in the simulation (with COMETA thermalhydraulic code) of an extended MFCI accident in a hypothetical reactor with arbitrary geometry. The objective was to correlate the initial conditions of the reactor with the phenomena evolution. (Author)

  1. Acceptance criteria for reactor coolant pumps and valves

    International Nuclear Information System (INIS)

    Each of the six primary coolant loop systems of the Savannah River Site (SRS) production reactors contains one reactor coolant pump, one PUMP suction side motor operated valve, and other smaller valves. The pumps me double suction, double volute, and radially split type pumps. The valves are different size shutoff and control valves rated from ANSI B16.5 construction class 150 to class 300. The reactor coolant system components, also known as the process water system (PWS), are classified as nuclear Safety Class I components. These components were constructed in the 1950's in accordance with the then prevailing industry practices. No uniform construction codes were used for design and analysis of these components. However, no pressure boundary failures or bolting failures have ever been recorded throughout their operating history. Over the years, the in-service inspection (ISI) was limited to visual inspection of the pressure boundaries, and surface and volumetric examination of the pressure retaining bolts. Efforts are now underway to implement ISI requirements similar to the ASME Section XI requirements for pumps and valves. This report discusses the new ISI requirements which also call for volumetric examination of the pump casing and valve body welds

  2. Investigation of steam explosion in stratified melt-coolant configuration

    International Nuclear Information System (INIS)

    We consider steam explosion in stratified melt–coolant configuration. Such configuration, with a liquid corium layer covered by water on top, can be formed in severe accident scenarios (1) with vessel failure and release and spreading of superheated corium melt on a floor of a shallow water pool; (2) with melt release and spreading in initially dry cavity later flooded with water from the top. In several previous assessments of stratified steam explosion energetics, it was assumed that melt-coolant interface is initially stable and there is no premixing prior to the shock wave propagation. This assumption was instrumental for the conclusion that amount of energy released in stratified steam explosion is limited and steam explosion in such configuration is not of safety importance. However, several recent experiments carried out in Pouring and Under-water Liquid Met Spreading (PULiMS) facility with up to 80 kg of superheated, binary oxidic corium simulants mixtures have resulted in spontaneous explosions with relatively high conversion ratios (about one percent). In apparent contradiction with the previous assumptions, the instability of the melt interface and formation of premixing layer were regularly observed in the tests. In this work we presents results of the recent experiments carried out in Steam Explosion in Stratified melt-coolant configuration (SES) facility in order to shed some light on the phenomena and assess the influence of test conditions on the steam explosion energetics. (author)

  3. A open-quotes zero wasteclose quotes coolant management strategy

    International Nuclear Information System (INIS)

    In June of 1992 the Waste Minimization Program at Rocky Flats Plant (RFP) began a study to determine the best methods of managing water-based industrial metalworking fluids in the plant's Tool Manufacturing Shop. The shop was faced with the challenge of managing fluids that could no longer be disposed of in the traditional manner, through the plant's liquid process waste drains, due to a problem they, were having causing in the Liquid Waste Operations Evaporator. The study's goal was to reduce the waste coolants being generated and to reduce worker exposure to a serious health risk. Results of this study and those of a subsequent study to determine relative compatibilities of various coolants and metals, led to the application of a open-quotes zero wasteclose quotes machine coolant management program. This program is currently saving the generation of 10,000 gallons of liquid waste annually, has eliminated worker exposure to harmful bacteria and biocides, and should result in extended machine tool life, increased product quality, fewer rejected parts, and decreases labor costs

  4. Crack stability analysis of low alloy steel primary coolant pipe

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.; Kameyama, M. [Kansai Electric Power Company, Osaka (Japan); Urabe, Y. [Mitsubishi Heavy Industries, Ltd., Takasago (Japan)] [and others

    1997-04-01

    At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

  5. The operating reliability of the reactor coolant pump

    International Nuclear Information System (INIS)

    There is a strong tendency among operating companies and manufacturers of nuclear power stations to further increase safety and operating availability of the plant and of its components. This applies also and particularly to reactor coolant pumps for the primary circuit of nuclear power stations of the type PWR. For 3 decades, ANDRITZ has developed and built such pumps and has attached great importance to the design of the complete pump rotor and of its essential surrounding elements, such as bearing and shaft seal. Apart from questions connected with design functioning of the pump there is one question of top priority: the operating reliability of the reactor coolant pump. The pump rotor (together with the rotor of the drive motor) is the only component within the primary system that permanently rotates at high speed during operation of the reactor plant. Many questions concerning design and configuration of such components cannot be answered purely theoretically, or they can only be answered partly. Therefore comprehensive development work and testing was necessary to increase the operating reliability of the pump rotor itself and of its surrounding elements. This contribution describes the current status of development and, as a focal point, discusses shaft sealing solutions elaborated so far. In this connection also a sealing system will be presented which aims for the first time at using a two-stage mechanical seal in reactor coolant pumps

  6. Radiolytic reactions in the coolant of helium cooled reactors

    International Nuclear Information System (INIS)

    The success of helium cooled reactors is dependent upon the ability to prevent significant reaction between the coolant and the other components in the reactor primary circuit. Since the thermal reaction of graphite with oxidizing gases is rapid at temperatures of interest, the thermal reactions are limited primarily by the concentration of impurity gases in the helium coolant. On the other hand, the rates of radiolytic reactions in helium are shown to be independent of reactive gas concentration until that concentration reaches a very low level. Calculated steady-state concentrations of reactive species in the reactor coolant and core burnoff rates are presented for current U. S. designed, helium cooled reactors. Since precise base data are not currently available for radiolytic rates of some reactions and thermal reaction rate data are often variable, the accuracy of the predicted gas composition is being compared with the actual gas compositions measured during startup tests of the Fort Saint Vrain high temperature gas-cooled reactor. The current status of these confirmatory tests is discussed. 12 references

  7. 进气掺水降低柴油机排放的实验研究%Experimental Study of Emission Reduction of Diesel Engine with Water Induction through Air Intake

    Institute of Scientific and Technical Information of China (English)

    李宏刚; 韩锐; 杨荣海; 张邢磊; 王娜

    2012-01-01

    在485QB柴油发动机上进行进气加湿降排的实验研究,实验采用超声雾化的方法产生微小的水颗粒,通过进气加入不同水量的排放实验,研究进气加湿对柴油机排放的影响。实验分析表明:对柴油发动机进气工质加湿可以有效地降低NOX的排放,一定程度上降低发动机的油耗,同时可以提高发动机的性能。%An experiment of decreasing emission of diesel engine with water induction through air intake was conducted in a 485QB engine.Tiny water particles were produced by ultrasonic atomizers.Through the emission experiments of adding different amount of water,the influence of water induction through air intake on diesel engine emissions was analyzed.Analysis of the experiment showed that water induction through the engine air intake can reduce NOx emissions effectively and reduce oil consumption to some extent,as well as improve the performance of the engine.

  8. The effect of air humidity of the combustion temperature and emission of harmful substances of supercharged internal combustion engines; Einfluss der Luftfeuchtigkeit auf die Verbrennungstemperatur und Schadstoffemission von aufgeladenen Verbrennungsmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Postrzednik, S.

    1993-12-31

    The purpose of the investigation in this work is the cooling process of the compressed combustion air, using a water injection process. An analysis of the effect of air humidity of the density of the combustion air (the degree of engine filling), on the combustion temperature and the associated emission of harmful substances is carried out. It was found theoretically and confirmed experimentally that the water injection process can lead to increasing the degree of engine filling and can simultaneously reduce the combustion temperature and emission of harmful substances. (orig.) [Deutsch] Der Untersuchungsgegenstand in dieser Arbeit ist der Abkuehlungsprozess der komprimierten Verbrennungsluft, mit der Anwendung vom Wassereinspritzverfahren. Es ist eine Analyse des Einflusses der Luftfeuchtigkeit auf die Dichte der Verbrennungsluft (den Motorfuellungsgrad), auf die Verbrennungstemperatur und damit verbundener Schadstoffemissionen durchgefuehrt. Theoretisch wurde es festgestellt und experimental bestaetigt, dass die realisierte Wassereinspritzverfahren zur Erhoehung des Motorfuellungsgrades und gleichzeitig zur Senkung der Verbrennungstemperatur und Schadstoffemission fuehren kann. (orig.)

  9. Air Conditioning Does Reduce Air Pollution Indoors

    Science.gov (United States)

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  10. A Real-Time Implementable NMPC Output Feedback for a Diesel Engine Air Path Commande prédictive non linéaire avec retour de sortie implémentable en temps-réel pour un circuit d’air d’un moteur Diesel

    Directory of Open Access Journals (Sweden)

    Murilo A.

    2011-09-01

    Full Text Available In this paper, an experimental validation of a parameterized Nonlinear Model Predictive Control (NMPC scheme with a Moving Horizon Observer (MHO is presented for a Diesel engine air path. The control design based on the parameterized approach leads to a low dimensional optimization problem which makes the proposed controller real-time implementable. An attractive feature of this control strategy lies in its compatibility with more elaborated and fully nonlinear models since it uses the model as a black box predictor. Dans cet article, une validation expérimentale d’un schéma de commande prédictive non linéaire (CPNL paramétrique avec un observateur à horizon glissant a été proposé pour le circuit d’air d’un moteur Diesel. La stratégie de commande basée sur l’approche paramétrique à faible dimension s’est montrée implémentable en temps réel et peut être utilisée aussi en tant qu’une solution du type boîte noire indépendamment de la structure du modèle non linéaire.

  11. Experimental investigations of BWR pressure suppression pool behavior under loss of coolant accident conditions

    International Nuclear Information System (INIS)

    The experiments discussed in this paper look into different processes which may occur during a loss-of-coolant accident in the pressure suppression pool of a Boiling Water Reactor (BWR). These processes include: a) development of a thermal stratification, b) bubble dynamics and related water flow during continuous release of air and c) air blowdown and associated water slug phenomenon in the water pool. The experiments have been performed in the THAI test facility, which is a cylindrical vessel of 9.2 m height, 3.2 m diameter and with a gas volume of 60 m3. The variation in the investigated test parameters included, steam and air mass flux, initial water pool temperature, blowdown pressures, downcomer submergence, etc. A systematic variation of the test parameters allowed better understanding of the phenomena. Experiments discussed in this paper were performed with a vertical downcomer of 0.1 m diameter and 2 m submergence depth in the water pool. For the blowdown experiments, a separate interconnecting vessel of 1 m3 volume was used to inject air at pressures between 3 bar and 10 bar. A high speed camera (1000 fps) was installed to visualize the formation and propagation of air bubbles in the suppression pool and the resulting pool swelling phenomena. Customized instrumentation applied during the tests included grids of densely spaced thermocouples and of pressure transducers at various locations in order to capture the temperature distribution in the pool and the water slug induced pressure loadings, respectively. The present paper discusses the main outcome of the selected experiments. On the whole the experimental data may be very useful for code validation. (authors)

  12. Process analysis of pressurized oxy-coal power cycle for carbon capture application integrated with liquid air power generation and binary cycle engines

    International Nuclear Information System (INIS)

    Highlights: • We model a 573 MW pressurized oxy-coal combustion with supercritical steam cycle. • A 126 MW liquid air power plant was integrated to utilize the nitrogen stream. • We used organic Rankine cycle to recover heat from compressors. • The model was analysed for with and without carbon capture consideration. • Efficiency increase of 12–15% was achieved due to integration and heat recovery. - Abstract: In this paper, the thermodynamic advantage of integrating liquid air power generation (LAPG) process and binary cycle waste heat recovery technology to a standalone pressurized oxy-coal combustion supercritical steam power generation cycle is investigated through modeling and simulation using Aspen Plus® simulation software version 8.4. The study shows that the integration of LAPG process and the use of binary cycle heat engine which convert waste heat from compressor exhaust to electricity, in a standalone pressurized oxy-coal combustion supercritical steam power generation cycle improves the thermodynamic efficiency of the pressurized oxy-coal process. The analysis indicates that such integration can give about 12–15% increase in thermodynamic efficiency when compared with a standalone pressurized oxy-coal process with or without CO2 capture. It was also found that in a pressurized oxy-coal process, it is better to pump the liquid oxygen from the cryogenic ASU to a very high pressure prior to vapourization in the cryogenic ASU main heat exchanger and subsequently expand the gaseous oxygen to the required combustor pressure than either compressing the atmospheric gaseous oxygen produced from the cryogenic ASU directly to the combustor pressure or pumping the liquid oxygen to the combustor pressure prior to vapourization in the cryogenic ASU main heat exchanger. The power generated from the compressor heat in the flue gas purification, carbon capture and compression unit using binary cycle heat engine was also found to offset about 65% of the

  13. Biofabrication and in vitro study of hydroxyapatite/mPEG–PCL–mPEG scaffolds for bone tissue engineering using air pressure-aided deposition technology

    International Nuclear Information System (INIS)

    The aims of this study were to fabricate biopolymer and biocomposite scaffolds for bone tissue engineering by an air pressure-aided deposition system and to carry out osteoblast cell culture tests to validate the biocompatibility of fabricated scaffolds. A mPEG–PCL–mPEG triblock copolymer was synthesized as a biopolymer material. Biocomposite material was composed of synthesized biopolymer and hydroxyapatite (HA) with a mean diameter of 100 μm. The weight ratio of HA added to the synthesized biopolymer was 0.1, 0.25, 0.5 and 1. The experimental results show that the maximum average compressive strength of biocomposite scaffolds, made of weight ratio 0.5, with mean pore size of 410 μm (porosity 81%) is 18.38 MPa which is two times stronger than that of biopolymer scaffolds. Osteoblast cells, MC3T3-E1, were seeded on both types of fabricated scaffolds to validate the biocompatibility using methylthianzol tetrazolium (MTT) assay and cell morphology observation. After 28 days of in vitro culturing, the seeded osteoblasts were well distributed in the interior of both types of scaffolds. Furthermore, MTT experimental results show that the cell viability of the biocomposite scaffold is higher than that of the biopolymer scaffold. This indicates that adding HA into synthesized biopolymer can enhance compressive strength and the proliferation of the osteoblast cell. Highlights: ► A mPEG-PCL-mPEG copolymer was synthesized as a biopolymer. ► Biocomposite was made of adding hydroxyapatite (HA) in biopolymer. ► Biopolyer and biocomposite scaffolds were made by an air pressure-aided deposition system. ► Average compressive strength of biocomposite scaffold is 18.38 MPa. ► After 28 days in vitro cell culturing, adding HA into biopolymer can enhance the proliferation.

  14. Biofabrication and in vitro study of hydroxyapatite/mPEG-PCL-mPEG scaffolds for bone tissue engineering using air pressure-aided deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Cho-Pei, E-mail: cpjiang@nfu.edu.tw [Department of Power Mechanical Engineering, National Formosa University, Yunlin County, Taiwan (China); Chen, Yo-Yu, E-mail: f90125@hotmail.com [Institute of Mechanical and Electro-Mechanical Engineering, National Formosa University, Yunlin County, Taiwan (China); Hsieh, Min-Fa, E-mail: mfhsieh@cycu.edu.tw [Department of Biomedical Engineering, Chung Yuan Christian University, Chung Li, Taiwan (China)

    2013-03-01

    The aims of this study were to fabricate biopolymer and biocomposite scaffolds for bone tissue engineering by an air pressure-aided deposition system and to carry out osteoblast cell culture tests to validate the biocompatibility of fabricated scaffolds. A mPEG-PCL-mPEG triblock copolymer was synthesized as a biopolymer material. Biocomposite material was composed of synthesized biopolymer and hydroxyapatite (HA) with a mean diameter of 100 {mu}m. The weight ratio of HA added to the synthesized biopolymer was 0.1, 0.25, 0.5 and 1. The experimental results show that the maximum average compressive strength of biocomposite scaffolds, made of weight ratio 0.5, with mean pore size of 410 {mu}m (porosity 81%) is 18.38 MPa which is two times stronger than that of biopolymer scaffolds. Osteoblast cells, MC3T3-E1, were seeded on both types of fabricated scaffolds to validate the biocompatibility using methylthianzol tetrazolium (MTT) assay and cell morphology observation. After 28 days of in vitro culturing, the seeded osteoblasts were well distributed in the interior of both types of scaffolds. Furthermore, MTT experimental results show that the cell viability of the biocomposite scaffold is higher than that of the biopolymer scaffold. This indicates that adding HA into synthesized biopolymer can enhance compressive strength and the proliferation of the osteoblast cell. Highlights: Black-Right-Pointing-Pointer A mPEG-PCL-mPEG copolymer was synthesized as a biopolymer. Black-Right-Pointing-Pointer Biocomposite was made of adding hydroxyapatite (HA) in biopolymer. Black-Right-Pointing-Pointer Biopolyer and biocomposite scaffolds were made by an air pressure-aided deposition system. Black-Right-Pointing-Pointer Average compressive strength of biocomposite scaffold is 18.38 MPa. Black-Right-Pointing-Pointer After 28 days in vitro cell culturing, adding HA into biopolymer can enhance the proliferation.

  15. Outline of cooling measures for enabling the operation of high-pressure coolant injection system among tsunami countermeasures at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Chubu Electric Power is now carrying out various Tsunami countermeasures works at Hamaoka Nuclear Power Station. This report is a summary of the air-cooled heat exchanger which is being set as alternative cooling measures for enabling operation of high-pressure coolant injection system at 'Loss of all AC power' and 'Loss of seawater cooling function' situation. (author)

  16. Loss-of-coolant and loss-of-flow accident in the ITER-EDA first wall/blanket cooling system

    International Nuclear Information System (INIS)

    This report presents the analysis of the transient thermal-hydraulic system behaviour inside the first wall/blanket cooling system and the resulting temperature response inside the first wall and blanket of the ITER-EDA (International Thermonuclear Experimental Reactor - Engineering Design Activities) reactor design during a: - Loss-of-coolant accident caused by a reputure of the pump suction pipe; - loss-of-flow accident caused by a trip of the recirculation pump. (orig.)

  17. Loss-of-coolant and loss-of-flow accident in the ITER-EDA first wall/blanket cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Komen, E.M.J.; Koning, H.

    1995-05-01

    This report presents the analysis of the transient thermal-hydraulic system behaviour inside the first wall/blanket cooling system and the resulting temperature response inside the first wall and blanket of the ITER-EDA (International Thermonuclear Experimental Reactor - Engineering Design Activities) reactor design during a: - Loss-of-coolant accident caused by a reputure of the pump suction pipe; - loss-of-flow accident caused by a trip of the recirculation pump. (orig.).

  18. COTELS fuel coolant interaction tests of UO2 debris dropping into water pool

    International Nuclear Information System (INIS)

    COTELS project aims at the investigation of ex-vessel debris coolability using a mixture of UO2, Zr, ZrO2 and stainless steel as simulant debris. The project consists of three types of test: Test A to focus on the investigation of a fuel coolant interaction (FCI) phenomena when a molten debris falls into coolant pool on the containment floor, Test B and Test C to focus on FCI and molten core concrete interaction (MCCI), respectively, when coolant is injected onto the molten debris as a severe accident management. This paper presents the results of the first test series, Test A. The test facility mainly consists of an electrical melting furnace (EMF) and a test vessel which receives the falling debris. EMF has a capability to melt 60 kg of UO2 mixture by induction heating and has a debris falling device to make a 5 cm diameter hole at the bottom of crucible instantaneously. The vessel is 0.8 m inner diameter and about 2.5 m height, and the design pressure is 10 MPa. A concrete floor of 5 cm thickness is used on the melt catcher in order to correctly simulate the effect of the interaction among debris, concrete and water. The observation of the molten debris jet behavior falling from EMF by high speed cameras showed that it was a continuous jet flow and little break-up to be occurred during falling process in air space. The debris jet velocity at pool surface was estimated to be about 6 m/s. In Test A, 60 kg of UO2 mixture dropped into water pool under around 0.2 MPa condition. The pool depth ranged from 0.4 m to 0.9 m and water subcooling was from zero to 20 K. Major findings from the experiments are as follows: (1) No pressure spike typical of violent steam explosion was observed in all the experiments. (2) The size of fragmented debris particles was large and ranged from 0.5 to 7 mm. (3) Solidified debris was easily removed from the concrete floor and no ablation was observed on the concrete surface. (author)

  19. 进气加湿对柴油机燃用不同牌号柴油NOx排放性能的影响%Influence of Water Induction on NOx Emission of Diesel Engine through Air Intake

    Institute of Scientific and Technical Information of China (English)

    韩锐; 李宏刚; 杨荣海; 张邢磊; 王娜

    2013-01-01

    在485QB型柴油发动机上进行了不同牌号柴油的进气加湿降排NOx的实验研究.实验采用超声波水雾化的方法对柴油发动机的进气进行加湿,通过湿空气与燃油的混合燃烧,研究NOx的排放性能,实验研究表明,不同牌号的柴油掺水燃烧均可以有效地降低NOx的排放浓度,能够在一定程度上降低发动机的燃油消耗率而且对发动机功率影响不大.%An experiment of NOx emission of diesel engine with water induction through air intake was conductea in 485QB engine.Humid air produced by ultrasonic atomizers is introduced through air intake and mixed with diesel oil.The results show that different types of diesels burning with humid air can reduce NOx emissions effectively with reduced oil consumption and a little impact to engine power.

  20. Numerical FEM Analyses of primary coolant system at NPP Temelin

    International Nuclear Information System (INIS)

    The main goal of this paper is to inform about the beginning and first steps of implementation of an aging management system at the Temelin NPP. The aging management system is important not only for achieving the current safety level but also for reaching operational reliability of a production unit equipment above the life time assumed by the original design, typically over 40 years. A method to locate the most prominent degradation regions is described. A global shell model of the primary coolant system including all loops and their components - reactor pressure vessel (RPV), steam generator (SG), main coolant pump (MCP), pressurizer, feed water and steam pipelines system is presented. The results of stress-strain analysis on the measured service parameters base are given. Validation of the results is very important and the method to compare the service measurement data with the numerical results is described. The global/local approach is mentioned and discussed. The effects of the complete global system on the individual components under monitoring are transformed into more accurate local spatial models. The local spatial models are used to analyze the gradual lifetime exhaustion of a facility during its service operation. Two spatial local models are presented, viz. feed water nozzle of SG and main coolant piping system T-brunch. The results of analysis of the local spatial models are processed by the neural network computing method, which is also described. The actual gradual damage of the material of the components under monitoring can be obtained based on the analyses performed and on the results from the neural network in combination with the knowledge of the real material characteristics. The procedures applied are included in the DIALIFE diagnostic system

  1. Fission product iodine behaviour in Sizewell B coolant

    International Nuclear Information System (INIS)

    Iodine concentrations in the primary coolant have been measured throughout the operational lifetime of Sizewell B. Fuel failures occurred in cycles 3 and 4, releasing fuel particulate which has been monitored by measuring 134I activity levels. The level of 134I was observed to increase during each reactor cycle after the fuel failures, as tramp fuel transferred either from out-of-core surfaces on to fuel or from low rated re-use fuel to higher rated fresh fuel. After each shutdown, however, the level of 134I decreases because fuel is removed, which leads to a gradual clean-up of the circuit. The rate of increase of 134I increased during cycle 10, indicating that there were fresh fuel failures. 131I and 132I are the most important isotopes and they behave quite differently during shut-down. 131I is removed from the circuit at the CVCS let-down flow rate although during one shut-down with the highest coolant concentrations there was evidence of reaction of iodine with surfaces and re-release after oxidising conditions were established. This suggests that hot reducing conditions should be maintained in order to ensure the efficient removal of the majority of the iodine. 132I is largely controlled by release from its parent 132Te, and this appears to be temperature dependent. Only a small fraction of 132Te is found in the coolant showing that it must be present on surfaces. This paper summarises the behaviour of iodine during normal operation and shut-down over the first 10 cycles of Sizewell B, and compares the data with those from other reactors. (author)

  2. The coolant void reactivity program in ZED-2

    International Nuclear Information System (INIS)

    The coolant void reactivity program at Chalk River produces reactor physics data for validating cell codes, in particular WIMS-AECL. One type of data provides detailed spectrum information within the various regions of a lattice cell. Most often however, the experiments are designed to provide the material buckling of a specific fuel type in a specific cell environment. Experiments are performed in the ZED-2 reactor. Fuel rod assemblies are positioned vertically, and the reactor is brought to criticality by reducing the neutron leakage from its top surface. This is done by raising the level of the heavy water moderator. The moderator height at the critical condition represents a key measurement in most experiments. The challenge is to covert this measurement, along with other supporting information such as foil activation data and moderator temperature, into the desired nuclear property of the test fuel - usually its material buckling. Since it's inception, the program has attempted to make measurements at conditions that are as close as possible to those in a power reactor. Most of the previous data available was for natural uranium at room temperature, the so called 'cold-clean' condition, and for the extreme ends of the coolant density range. Extending these conditions necessitated including effects of fuel burnup and the temperature of the fuel and coolant. A major component of the program has been to develop techniques for acquiring as much of that information as possible while operating within the constraints of a limited budget and the capabilities of a zero-energy critical facility. In the following sections, the progress made in developing some of the techniques necessary for generating data at power reactor conditions will be reviewed. A limited comparison with WIMS-AECL calculated values will also be made where appropriate. (author)

  3. Cold neutron tomography of annular coolant flow in a double subchannel model of a boiling water reactor

    International Nuclear Information System (INIS)

    Dryout of the liquid coolant film on fuel pins at the top of boiling water reactor (BWR) cores constitutes the type of heat transfer crisis relevant for the conditions of high void fractions. It is a limiting factor in the thermal power, and therefore the economy, of BWRs. Ongoing research on multiphase annular flow, specifically the liquid film thickness, is fundamental not only to nuclear reactor safety and operation but also to that of evaporators, condensers, and pipelines in a general industrial context. We have performed cold neutron tomography of adiabatic air water annular flow in a scaled up model of the subchannel geometry found in BWR fuel assemblies today. All imaging has been performed at the ICON beamline at the neutron spallation source SINQ at the Paul Scherrer Institut in Switzerland. Neutron tomography is shown to excel in investigating the interactions of air water two phase flows with spacer vanes of different geometry. The high resolution, high contrast measurements provide spatial distributions of the coolant on top of the surfaces of the spacer, including the vanes, and in the subchannel downstream of the spacers.

  4. Modelling the transient pressurisation during a molten fuel coolant interaction

    International Nuclear Information System (INIS)

    Model predictions of the transient pressurisation produced during a molten fuel coolant interaction using two different assumptions about loading mechanisms are compared. The two types of loading examined are inertial loading, where a Newtonian model is applied and acoustic loading, where the compressibility of water is taken into account. Computational results show that these two models produce significantly different transient pressurisation during the heat transfer stage. It is concluded that any transient pressurisation model should take the compressibility of water into account until the system has had sufficient time for acoustic relief to occur. (author)

  5. System Study: High-Pressure Coolant Injection 1998-2014

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2015-12-01

    This report presents an unreliability evaluation of the high-pressure coolant injection system (HPCI) at 25 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCI results.

  6. System Study: High-Pressure Coolant Injection 1998–2013

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2015-01-31

    This report presents an unreliability evaluation of the high-pressure coolant injection system (HPCI) at 25 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCI results.

  7. Maximum likelihood factor analysis of the reactor coolant pump system

    International Nuclear Information System (INIS)

    In today's operating environment of nuclear power plants, setpoints are established for key plant parameters, such as temperature, pressure, and flow rate. Reducing excursions beyond these setpoints would save millions of dollars as a result of improved plant availability and improve plant safety as well. The statistical method of maximum likelihood factor analysis is presented, and the results of two computer runs are given. The results of the statistical analysis indicate that it is possible to consistently rank order the eleven tracked variables of the reactor coolant system. Implementation of the maximum likelihood factor method would permit the decision maker to predict unanticipated transients and reduce plant unavailability

  8. Nuclear reactor coolant pump having a tooling boom

    International Nuclear Information System (INIS)

    A reactor coolant pump having a tooling boom mounted on the periphery of the motor stand of the pump for transferring pump components through openings in the motor stand during performance of maintenance on the pump are described. The tooling boom comprises an articulated arm mounted on the periphery of the motor stand with a gripping mechanism attached to the arm at the end opposite the arm's attachement to the motor stand. The gripping mechanism is capable of having pump components firmly attached thereto so that when the articulated arm is swung in the horizontal plane, the pump components may be transferred between the inside and outside of the motor stand

  9. Loss of coolant accident at boiling water reactors

    International Nuclear Information System (INIS)

    A revision is made with regard to the methods of thermohydraulic analysis which are used at present in order to determine the efficiency of the safety systems against loss of coolant at boiling water reactors. The object is to establish a program of work in the INEN so that the personnel in charge of the safety of the nuclear plants in Mexico, be able to make in a near future, independent valuations of the safety systems which mitigate the consequences of the above mentioned accident. (author)

  10. Dynamic analysis of the rotor of SMART main coolant pump

    International Nuclear Information System (INIS)

    A main coolant pump(MCP) is an essential device of the SMART integral reactor and required to be used in high temperature and high pressure working fluid during 10 more years. Therefore, t is needed to reflect considerations in the design of MCP structure and component from the early design phase to keep enough stability margin by obtaining the dynamic characteristics of the MCP rotor. Especially, excessive vibration can be escaped by allocating natural frequencies propertly from running speeds to get maximum critical speed margin. In this paper, modeling and analysis utlizing FEM and ESDM to optimize the size and configuration of MCP rotor is accomplished

  11. Coordinated research programs on loss of coolant problems

    International Nuclear Information System (INIS)

    The hypothetical primary coolant loss accident in pressurized water reactors is the object of many studies between the CEA, EDF and Framatome. The builder must perform calculations for safety reports, bearing on emergency core cooling, mechanical resistance of the core and primary circuit component structures, mechanical and thermal stresses in the containment vessel and post-accident chemical reactions. The safety studies concern emergency core cooling, flows, heat exchanges, steam-cold water interactions, behaviour of the pumps and pressurization of the containment vessel. France has also set up agreements with several countries for the exchange of informations

  12. Modelling transient energy release from molten fuel coolant interaction debris

    International Nuclear Information System (INIS)

    A simple model of transient energy release in a Molten Fuel Coolant Interaction is presented. A distributed heat transfer model is used to examine the effect of heat transfer coefficient, time available for rapid energy heat transfer and particle size on transient energy release. The debris is assumed to have an Upper Limit Lognormal distribution. Model predictions are compared with results from the SUW series of experiments which used thermite-generated uranium dioxide molybdenum melts released below the surface of a pool of water. Uncertainties in the physical principles involved in the calculation of energy transfer rates are discussed. (author)

  13. Reactor coolant pump shaft seal stability during station blackout

    International Nuclear Information System (INIS)

    Results are presented from an investigation into the behavior of Reactor Coolant Pump shaft seals during a potential station blackout (loss of all ac power) at a nuclear power plant. The investigation assumes loss of cooling to the seals and focuses on the effect of high temperature on polymer seals located in the shaft seal assemblies, and the identification of parameters having the most influence on overall hydraulic seal performance. Predicted seal failure thresholds are presented for a range of station blackout conditions and shaft seal geometries

  14. Definition of loss-of-coolant accident radiation source

    International Nuclear Information System (INIS)

    Meaningful qualification testing of nuclear reactor components requires a knowledge of the radiation fields expected in a loss-of-coolant accident (LOCA). The overall objective of this program is to define the LOCA source terms and compare these with the output of various simulators employed for radiation qualification testing. The basis for comparison will be the energy deposition in a model reactor component. The results of the calculations are presented and some interpretation of the results given. The energy release rates and spectra were validated by comparison with other calculations using different codes since experimental data appropriate to these calculations do not exist

  15. PUMP: analog-hybrid reactor coolant hydraulic transient model

    International Nuclear Information System (INIS)

    The PUMP hybrid computer code simulates flow and pressure distribution; it is used to determine real time response to starting and tripping all combinations of PWR reactor coolant pumps in a closed, pressurized, four-pump, two-loop primary system. The simulation includes the description of flow, pressure, speed, and torque relationships derived through pump affinity laws and from vendor-supplied pump zone maps to describe pump dynamic characteristics. The program affords great flexibility in the type of transients that can be simulated

  16. Improvement of TRAC-BF1 code to analyze the Ingress of Coolant Event (ICE)

    International Nuclear Information System (INIS)

    JAERI is performing the Ingress of Coolant Event (ICE) preliminary experiment as one of the technology R and D tasks for the International Thermonuclear Experimental Reactor (ITER). The Transient Reactor Analysis Code (TRAC) was improved and arranged as the ICE experimental analysis code. The TRAC-BF1 code was originally developed for the thermal hydraulics safety analysis of the boiling water reactor (BWR) at the Idaho National Engineering Laboratory (INEL) in USA. We partially modified the code to be applicable for the ICE analysis such as adding the heat transfer model in the VESSEL element plane surface, individual appointment of thermal transfer calculation mesh in VESSEL element. Moreover, the IPLOT program and the GCONV program was introduced to the engineering workstation (EWS) for plotting calculation outputs of TRAC-BF1 code. This paper describes a summary of the improved TRAC-BF1 code, and verification results of the modification of the TRAC-BF1 code, and ICE experimental analyzed result. (author)

  17. Investigations of Air-cooled Turbine Rotors for Turbojet Engines II : Mechanical Design, Stress Analysis, and Burst Test of Modified J33 Split-disk Rotor / Richard H. Kemp and Merland L. Moseson

    Science.gov (United States)

    Kemp, Richard H; Moseson, Merland L

    1952-01-01

    A full-scale J33 air-cooled split turbine rotor was designed and spin-pit tested to destruction. Stress analysis and spin-pit results indicated that the rotor in a J33 turbojet engine, however, showed that the rear disk of the rotor operated at temperatures substantially higher than the forward disk. An extension of the stress analysis to include the temperature difference between the two disks indicated that engine modifications are required to permit operation of the two disks at more nearly the same temperature level.

  18. Dry storage systems with free convection air cooling

    International Nuclear Information System (INIS)

    Several design principles to remove heat from the spent fuel by free air convection are illustrated and described. The key safety considerations were felt to be: loss of coolant is impossible as the passive system uses air as a coolant; overheating is precluded because as the temperatures of the containers rises the coolant flow rate increases; mass of the storage building provides a large heat sink and therefore a rapid temperature rise is impossible; and lack of any active external support requirements makes the cooling process less likely to equipment or operator failures. An example of this type of storage already exists. The German HTGR is operated with spherical graphite fuel elements which are stored in canister and in storage cells. The concept is a double cooling system with free convection inside the cells and heat exchange via two side walls of the cell to the ambient air in the cooling ducts. Technical description of the TN 1300 cask is also presented

  19. Degradation Analyses Of The Primary Water Coolant Quality Reactor TRIGA Mark II Bandung

    International Nuclear Information System (INIS)

    Analysis has been determine by considering the primary water coolant quality data. There for the degradation of the primary water coolant quality has been indicated by increasing concentration of Si O sub.2. The increasing Si O sub.2 concentration on the primary water coolant reactor caused by corrosion material internal reactor, flay ask, water purification system, interaction high energy neutron with aluminium alloy and reactor ventilation system

  20. An advanced CANDU reactor with supercritical water coolant: conceptual design features

    International Nuclear Information System (INIS)

    AECL is studying an advanced CANDU reactor concept, with supercritical steam as coolant. The coolant, being a high density gas, at a pressure above 22 MPa and temperatures above 370 deg C, does not encounter the two-phase region with its associated fuel-dryout and flow-instability problems. Increased coolant temperature leads directly to increased plant thermodynamic efficiency, thereby reducing unit energy cost through reduced specific capital cost and reduced fueling cost. The reduced coolant in-core density leads to sufficiently reduced void reactivity, so that light water becomes a coolant option. The use of supercritical water coolant also opens up the possibility of enhanced safety with a natural circulation primary flow, taking advantage of the gas expansion coefficient. To preserve neutron economy, especially at high coolant temperatures, a fuel channel that is currently being developed has a pressure tube that is thermally insulated from high-temperature coolant and is in contact with the cold heavy-water moderator. Two stages of development of a supercritical-cooled CANDU reactor were identified. The first uses conventional or near-conventional zirconium-alloy fuel cladding with coolant core-mean temperatures near 400 deg C, and the second uses advanced high-temperature fuel cladding at coolant core-mean temperatures near 500 deg C. A first-stage cost reduction of 20% from the CANDU 6 design is estimated as a result of improved thermodynamic efficiency. A large change in coolant density across the core leads to a factor 3 or 4 reduction in heavy-water inventory and a corresponding reduction in coolant void reactivity. The latter leads to improved fuel burnup and reduced demands on the safety shutdown systems. (author)