WorldWideScience

Sample records for exhaust gas heat

  1. Low-pressure-ratio regenerative exhaust-heated gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

    1991-01-01

    A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

  2. Performance and Reliability of Exhaust Gas Waste Heat Recovery Units

    Science.gov (United States)

    2014-09-01

    Khalil, Zohir, and Farid (2010) investigated heat transfer related to swirling and non- swirling flows through sudden pipe expansions at constant pumping... swirl in air flow in a tube for a concentric double- pipe heat exchanger. The use of a snail entrance feature increased the Nusselt number in the...exhaust gas WHRU. 14. SUBJECT TERMS waste heat recovery, heat recovery performance, swirling flow , pressure drop penalty, temperature

  3. Gas turbine cogeneration: the use of heat pipes to recover exhaust gas energy

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, J. L.; Perella Balestieri, J. A.; Masanobu Tanisho, P.; Araujo Zanardi, M.; Murcia, N. [Paulista State University, Guaratingueta (Brazil)

    1996-12-31

    Heat pipe heat exchangers for the recovery of exhaust gas heat from gas turbines for the simultaneous cogeneration of electricity were described. Technical and economic implications were reviewed. The overall conclusion was that cogeneration systems using heat pipe heat exchanger technology could be a useful alternative in the supply and use of energy, of particular interest for application in industrial, hospital, hotel or other large building system environment. 8 refs., 3 tabs., 5 figs.

  4. Low-pressure-ratio regenerative exhaust-heated gas turbine. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

    1991-01-01

    A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

  5. Study on heat pipe assisted thermoelectric power generation system from exhaust gas

    Science.gov (United States)

    Chi, Ri-Guang; Park, Jong-Chan; Rhi, Seok-Ho; Lee, Kye-Bock

    2017-11-01

    Currently, most fuel consumed by vehicles is released to the environment as thermal energy through the exhaust pipe. Environmentally friendly vehicle technology needs new methods to increase the recycling efficiency of waste exhaust thermal energy. The present study investigated how to improve the maximum power output of a TEG (Thermoelectric generator) system assisted with a heat pipe. Conventionally, the driving energy efficiency of an internal combustion engine is approximately less than 35%. TEG with Seebeck elements is a new idea for recycling waste exhaust heat energy. The TEG system can efficiently utilize low temperature waste heat, such as industrial waste heat and solar energy. In addition, the heat pipe can transfer heat from the automobile's exhaust gas to a TEG. To improve the efficiency of the thermal power generation system with a heat pipe, effects of various parameters, such as inclination angle, charged amount of the heat pipe, condenser temperature, and size of the TEM (thermoelectric element), were investigated. Experimental studies, CFD simulation, and the theoretical approach to thermoelectric modules were carried out, and the TEG system with heat pipe (15-20% charged, 20°-30° inclined configuration) showed the best performance.

  6. Study on heat pipe assisted thermoelectric power generation system from exhaust gas

    Science.gov (United States)

    Chi, Ri-Guang; Park, Jong-Chan; Rhi, Seok-Ho; Lee, Kye-Bock

    2017-04-01

    Currently, most fuel consumed by vehicles is released to the environment as thermal energy through the exhaust pipe. Environmentally friendly vehicle technology needs new methods to increase the recycling efficiency of waste exhaust thermal energy. The present study investigated how to improve the maximum power output of a TEG (Thermoelectric generator) system assisted with a heat pipe. Conventionally, the driving energy efficiency of an internal combustion engine is approximately less than 35%. TEG with Seebeck elements is a new idea for recycling waste exhaust heat energy. The TEG system can efficiently utilize low temperature waste heat, such as industrial waste heat and solar energy. In addition, the heat pipe can transfer heat from the automobile's exhaust gas to a TEG. To improve the efficiency of the thermal power generation system with a heat pipe, effects of various parameters, such as inclination angle, charged amount of the heat pipe, condenser temperature, and size of the TEM (thermoelectric element), were investigated. Experimental studies, CFD simulation, and the theoretical approach to thermoelectric modules were carried out, and the TEG system with heat pipe (15-20% charged, 20°-30° inclined configuration) showed the best performance.

  7. Exhaust bypass flow control for exhaust heat recovery

    Science.gov (United States)

    Reynolds, Michael G.

    2015-09-22

    An exhaust system for an engine comprises an exhaust heat recovery apparatus configured to receive exhaust gas from the engine and comprises a first flow passage in fluid communication with the exhaust gas and a second flow passage in fluid communication with the exhaust gas. A heat exchanger/energy recovery unit is disposed in the second flow passage and has a working fluid circulating therethrough for exchange of heat from the exhaust gas to the working fluid. A control valve is disposed downstream of the first and the second flow passages in a low temperature region of the exhaust heat recovery apparatus to direct exhaust gas through the first flow passage or the second flow passage.

  8. Exhaust gas heat recovery through secondary expansion cylinder and water injection in an internal combustion engine

    Directory of Open Access Journals (Sweden)

    Nassiri Toosi Ali

    2017-01-01

    Full Text Available To enhance thermal efficiency and increase performance of an internal combustion engine, a novel concept of coupling a conventional engine with a secondary 4-stroke cylinder and direct water injection process is proposed. The burned gases after working in a traditional 4-stroke combustion cylinder are transferred to a secondary cylinder and expanded even more. After re-compression of the exhaust gases, pre-heated water is injected at top dead center. The evaporation of injected water not only recovers heat from exhaust gases, but also increases the mass of working gas inside the cylinder, therefore improves the overall thermal efficiency. A 0-D/1-D model is used to numerically simulate the idea. The simulations outputs showed that the bottoming cycle will be more efficient at higher engines speeds, specifically in a supercharged/turbocharged engine, which have higher exhaust gas pressure that can reproduce more positive work. In the modeled supercharged engine, results showed that brake thermal efficiency can be improved by about 17%, and brake power by about 17.4%.

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

    DEFF Research Database (Denmark)

    Kyriakidis, Fotis; Sørensen, Kim; Singh, Shobhana

    2017-01-01

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

  10. Devise of an exhaust gas heat exchanger for a thermal oil heater in a palm oil refinery plant

    Science.gov (United States)

    Chucherd, Panom; Kittisupakorn, Paisan

    2017-08-01

    This paper presents the devise of an exhaust gas heat exchanger for waste heat recovery of the exhausted flue gas of palm oil refinery plant. This waste heat can be recovered by installing an economizer to heat the feed water which can save the fuel consumption of the coal fired steam boiler and the outlet temperature of flue gas will be controlled in order to avoid the acid dew point temperature and protect the filter bag. The decrease of energy used leads to the reduction of CO2 emission. Two designed economizer studied in this paper are gas in tube and water in tube. The gas in tube exchanger refers to the shell and tube heat exchanger which the flue gas flows in tube; this designed exchanger is used in the existing unit. The new designed water in tube refers to the shell and tube heat exchanger which the water flows in the tube; this designed exchanger is proposed for new implementation. New economizer has the overall coefficient of heat transfer of 19.03 W/m2.K and the surface heat transfer area of 122 m2 in the optimized case. Experimental results show that it is feasible to install economizer in the exhaust flue gas system between the air preheater and the bag filter, which has slightly disadvantage effect in the system. The system can raise the feed water temperature from 40 to 104°C and flow rate 3.31 m3/h, the outlet temperature of flue gas is maintained about 130 °C.

  11. The production of electrical and thermal energy from the exhaust gas heat of preheater kilns

    Energy Technology Data Exchange (ETDEWEB)

    Lang, T.A.; Mosimann, P.

    1984-05-01

    It is shown, by means of an example, i.e., a 1600-ton/day four-stage suspension preheater kiln of a cement factory, that the waste heat present in the exhaust gases can be converted into useful electrical and thermal energy. This is possible even though the exhaust gases are heavily loaded with dust. The heat recovery system installed in 1981/1982 in a Swiss cement plant and the respective production line are described in detail. A comprehensive explanation is given concerning the experience of the first operating year, the interaction of the new plant with the existing production facilities, and the current measured technical data. The performance limits for economic operation are explained and the decision criteria quoted. Further applications of the successfully tested heat recovery system can be expected wherever heat sources in the form of heavily loaded gases are available.

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

    DEFF Research Database (Denmark)

    Kyriakidis, Fotis; Sørensen, Kim; Singh, Shobhana

    2017-01-01

    is optimized to utilize the maximum waste heat recovery. The Genetic algorithm and fmincon active-set algorithm are used to optimize the design and operation parameters for the two steam cycles. The optimization aims to find the theoretically optimal combination of the pressure levels and pinch......Waste heat recovery combined with exhaust gas recirculation is a promising technology that can address both the issue of NOx (nitrogen oxides) reduction and fuel savings by including a pressurized boiler. In the present study, a theoretical optimization of the performance of two different...... configurations of steam Rankine cycles, with integrated exhaust gas recirculation for a marine diesel engine, is presented. The first configuration employs two pressure levels and the second is configured with three-pressure levels. The models are developed in MATLAB based on the typical data of a large two...

  13. Cogeneration with gas turbines. Use of heat pipe type exchangers for the energy recuperation of exhausted gases; Cogeracao com turbinas a gas. O uso de trocador tipo tubos de calor (heat pipe) para a recuperacao energetica dos gases de exaustao

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Jose Luz; Balestieri, Jose A.P.; Tanisho, Petronio Masanobu; Zanardi, Mauricio Araujo; Murcia, Nelson [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Energia

    1995-07-01

    Gas turbine cogeneration systems are being widely used in the simultaneous production of electricity and useful heat. Several devices can be indicated to the recovery of exhaust gas heat from gas turbine systems, for example heat recovery steam generators, boiling-water heaters, absorption refrigerating systems (cooled water), drying systems (heated air), each one indicated for a specific use of recovery heat. In this paper it is proposed the use of heat pipes exchangers in the recovery of exhaust gas heat to produce heated water to be used in a process. Heat pipes are devices that has high thermal conductance that can be used to reduce thermal losses to the environment. The use of heat pipes in these types of equipment can provide heat recoveries of high efficiency since both fluid flows are external and there are less contamination risks between the hot and cold streams. (author)

  14. Brayton cycle for internal combustion engine exhaust gas waste heat recovery

    Directory of Open Access Journals (Sweden)

    J Galindo

    2015-06-01

    Full Text Available An average passenger car engine effectively uses about one-third of the fuel combustion energy, while the two-thirds are wasted through exhaust gases and engine cooling. It is of great interest to automotive industry to recover some of this wasted energy, thus increasing the engine efficiency and lowering fuel consumption and contamination. Waste heat recovery for internal combustion engine exhaust gases using Brayton cycle machine was investigated. The principle problems of application of such a system in a passenger car were considered: compressor and expander machine selection, machine size for packaging under the hood, efficiency of the cycle, and improvement of engine efficiency. Important parameters of machines design have been determined and analyzed. An average 2-L turbocharged gasoline engine’s New European Driving Cycle points were taken as inlet points for waste heat recovery system. It is theoretically estimated that the recuperated power of 1515 W can be achieved along with 5.7% improvement in engine efficiency, at the point where engine power is 26550 W.

  15. Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat

    Science.gov (United States)

    Pak, Pyong Sik

    A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.

  16. Study on waste heat recovery from exhaust gas spark ignition (S.I. engine using steam turbine mechanism

    Directory of Open Access Journals (Sweden)

    Talib Kamarulhelmy

    2017-01-01

    Full Text Available The issue of global warming has pushed the effort of researchers not only to find alternative renewable energy, but also to improve the machine’s energy efficiency. This includes the utilization of waste energy into ‘useful energy’. For a vehicle using internal combustion engine (ICE, the waste energy produce by exhaust gas can be utilize to ‘useful energy’ up to 34%. The energy from the automotive exhaust can be harness by implementing heat pipe heat exchanger in the automotive system. In order to maximize the amount of waste energy that can be turned to ‘useful energy’, the used of appropriate fluid in the heat exchanger is important. In this study, the fluid used is water, thus converting the fluid into steam and thus drive the turbine that coupling with generator. The paper will explore the performance of a naturally aspirated spark ignition (S.I. engine equipped with waste heat recovery mechanism (WHRM that used water as the heat absorption medium. The experimental and simulation test suggest that the concept is thermodynamically feasible and could significantly enhance the system performance depending on the load applied to the engine.

  17. EHMS: Exhaust Heat Management System

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, T.; Schmidt, M.; Weinbrenner, M.; Geskes, P. [Behr GmbH und Co. KG, Stuttgart (Germany)

    2006-07-01

    Pollutant concentrations in diesel engines are reduced by cooling of the recirculated exhaust. This reduces emissions and particulate matter. The cooler technology can also be used for heating the passenger compartment faster and more economically. The authors present a model ready for seral production, including an exhaust flap for bypass control for use as auxiliary heating system. Further applications in gasoline engines are pointed out. (orig.)

  18. Heat Exhaustion and Heatstroke

    Science.gov (United States)

    ... of salt contribute to heat-related illnesses. Some sports drinks can help replenish the salt in your body ... temperature.Drink fluids, such as water or a sports drink. Do not guzzle them, but take sips. Do ...

  19. Implementation of Exhaust Gas Recirculation for Double Stage Waste Heat Recovery System on Large Container Vessel

    DEFF Research Database (Denmark)

    Andreasen, Morten; Marissal, Matthieu; Sørensen, Kim

    2014-01-01

    Concerned to push ships to have a lower impact on the environment, the International Maritime Organization are implementing stricter regulation of NOx and SOx emissions, called Tier III, within emission control areas (ECAs). Waste Heat Recovery Systems (WHRS) on container ships consist...

  20. Concept of Heat Recovery from Exhaust Gases

    Science.gov (United States)

    Bukowska, Maria; Nowak, Krzysztof; Proszak-Miąsik, Danuta; Rabczak, Sławomir

    2017-10-01

    The theme of the article is to determine the possibility of waste heat recovery and use it to prepare hot water. The scope includes a description of the existing sample of coal-fired boiler plant, the analysis of working condition and heat recovery proposals. For this purpose, a series of calculations necessary to identify the energy effect of exhaust temperature decreasing and transferring recovery heat to hot water processing. Heat recover solutions from the exhaust gases channel between boiler and chimney section were proposed. Estimation for the cost-effectiveness of such a solution was made. All calculations and analysis were performed for typical Polish conditions, for coal-fired boiler plant. Typicality of this solution is manifested by the volatility of the load during the year, due to distribution of heat for heating and hot water, determining the load variation during the day. Analysed system of three boilers in case of load variation allows to operational flexibility and adaptation of the boilers load to the current heat demand. This adaptation requires changes in the operating conditions of boilers and in particular assurance of properly conditions for the combustion of fuel. These conditions have an impact on the existing thermal loss and the overall efficiency of the boiler plant. On the boiler plant efficiency affects particularly exhaust gas temperature and the excess air factor. Increasing the efficiency of boilers plant is possible to reach by following actions: limiting the excess air factor in coal combustion process in boilers and using an additional heat exchanger in the exhaust gas channel outside of boilers (economizer) intended to preheat the hot water.

  1. Motor Vehicle Exhaust Gas Suicide.

    Science.gov (United States)

    Routley, Virginia

    2007-01-01

    In many motorized countries, inhalation of carbon monoxide from motor vehicle exhaust gas (MVEG) has been one of the leading methods of suicide. In some countries it remains so (e.g., Australia 16.0% of suicides in 2005). Relative to other methods it is a planned method and one often used by middle-aged males. The study provides a review of countermeasures aimed at restricting this method of suicide. The prevention measures identified were catalytic converters (introduced to reduce carbon monoxide for environmental reasons); in-cabin sensors; exhaust pipe modification; automatic idling stops; and helpline signage at suicide "hotspots." Catalytic converters are now in 90% of new vehicles worldwide and literature supports them being associated with a reduction in exhaust-gassing suicides. There remain, however, accounts of exhaust-gas fatalities in modern vehicles, whether accidentally or by suicide. These deaths and also crashes from fatigue could potentially be prevented by in-cabin multi-gas sensors, these having been developed to the prototype stage. Helpline signage at an exhaust-gassing suicide "hotspot" had some success in reducing suicides. The evidence on method substitution and whether a reduction in MVEG suicides causes a reduction in total suicides is inconsistent.

  2. Exhaust Gas Scrubber Washwater Effluent

    Science.gov (United States)

    2011-11-01

    10 Sulfur Content of Certain Liquid Fuels Exhaust Gas Scrubber Washwater Effluent...diesel and gasoline components DIN Dissolved inorganic nitrogen THC Total hydrocarbon TKN Total Kjeldahl nitrogen HEM Hexane extractable...Benefit Analysis to support the impact assessment accompanying the revision of Directive 1999/32/EC on the sulfur content of certain liquid fuels

  3. Ship exhaust gas plume cooling

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Neele, P.P.

    2004-01-01

    The exhaust gas plume is an important and sometimes dominating contributor to the infrared signature of ships. Suppression of the infrared ship signatures has been studied by TNO for the Royal Netherlands Navy over considerable time. This study deals with the suppression effects, which can be

  4. Low exhaust temperature electrically heated particulate matter filter system

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J.; Bhatia, Garima [Bangalore, IN

    2012-02-14

    A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.

  5. Heat pipes and use of heat pipes in furnace exhaust

    Science.gov (United States)

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  6. Exhaust gas recirculation system for an internal combustion engine

    Science.gov (United States)

    Wu, Ko-Jen

    2013-05-21

    An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

  7. 14 CFR 29.1125 - Exhaust heat exchangers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust heat exchangers. 29.1125 Section 29... exchangers. For reciprocating engine powered rotorcraft the following apply: (a) Each exhaust heat exchanger... is subject to contact with exhaust gases; and (4) No exhaust heat exchanger or muff may have stagnant...

  8. 14 CFR 25.1125 - Exhaust heat exchangers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust heat exchangers. 25.1125 Section 25... exchangers. For reciprocating engine powered airplanes, the following apply: (a) Each exhaust heat exchanger... provisions wherever it is subject to contact with exhaust gases; and (4) No exhaust heat exchanger or muff...

  9. [Poisoning by exhaust gas of the imperfect combustion of natural gas: 22 cases study].

    Science.gov (United States)

    Dong, Li-Min; Zhao, Hai; Zhang, Ming-Chang; He, Meng

    2014-10-01

    To analyze the case characteristics of poisoning by exhaust gas of the imperfect combustion of natural gas and provide references for forensic identification and prevention of such accidents. Twenty-two cases of poisoning by exhaust gas of the imperfect combustion of natural gas in Minhang District during 2004 to 2013 were collected. Some aspects such as general conditions of deaths, incidence time, weather, field investigation, and autopsy were retrospectively analyzed. In the 22 cases, there were 15 males and 16 females. The age range was between 2 and 82 years old. The major occurring time was in January or February (8 cases in each) and the cases almost occurred in small area room (21 cases). There was wide crack next to the exhaust port when the gas water heater was been used in all cases. There are more prone to occurrence of exhaust gas poisoning of imperfect combustion of natural gas in small area room with a ventilation window near the exhaust port of gas water heated. It shows that the scene of combustion exhaust gas poisoning should be more concerned in the cold season.

  10. 14 CFR 23.1125 - Exhaust heat exchangers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust heat exchangers. 23.1125 Section 23... § 23.1125 Exhaust heat exchangers. For reciprocating engine powered airplanes the following apply: (a) Each exhaust heat exchanger must be constructed and installed to withstand the vibration, inertia, and...

  11. Heat recovery from Diesel exhausts by means of a fluidized bed heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Carlomagno, G.M.; Festa, R.; Massimilla, L.

    1983-01-01

    A fluidized bed heat exchanger, equipped with a specially designed manifold gas distributor, is conveniently used to recover heat from exhausts of a 60 kW Diesel engine. The sensitivity of the bed to tube heat transfer coefficient to soot fouling and the sensitivity of the exchanger efficiency to variations of such coefficients are analyzed. Procedures for in-operation tube defouling are described.

  12. Experimental Design of Compact Heat Exchanger for Waste Heat Recovery of Diesel Engine Exhaust Gases for Grain Dryers

    OpenAIRE

    Aziz, Nasruddin

    2016-01-01

    Abstract??? In diesel engine cycle, 35% of energy losses through the exhaust gases, the heat is an energy potential that can still be reused for various purposes. This research aims to design a heat exchanger, based of diesel engine exhaust gases integrated with rice milling unit for drying agricultural products. The exhaust gas is derived from 6D16 diesel engine of 120 kVA as a power generator for rice milling unit at South Sulawesi. Exhaust gas temperature reaches 357oC with the mass flow r...

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

    OpenAIRE

    Wail Aladayleh; Ali Alahmer

    2015-01-01

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

  14. Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2017-01-01

    Full Text Available The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG of combined-cycle gas turbine (CCGT. Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion products and the amount of water vapor produced according to a given composition of the burned gas and determine the amount of moisture that will be obtained as a result of condensation at a given temperature of the flue gases at the outlet of the condensation heat exchanger (CHE. To calculate the efficiency of the HRSG taking into account the heat of condensation of moisture in the CHE an equation is derived.

  15. 40 CFR 89.416 - Raw exhaust gas flow.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Raw exhaust gas flow. 89.416 Section... Procedures § 89.416 Raw exhaust gas flow. The exhaust gas flow shall be determined by one of the methods...) Measurement of the air flow and the fuel flow by suitable metering systems (for details see SAE J244. This...

  16. The exhaust heat management system; Das Abgaswaerme-Management

    Energy Technology Data Exchange (ETDEWEB)

    Geskes, P.; Strauss, T. [Behr GmbH und Co., Stuttgart (Germany)

    2006-10-15

    Behr uses EGR coolers in its Exhaust Heat Management System (EHMS) to obtain exhaust enthalpy, helping to heat up the vehicle cabin faster, or to reduce the power train warm-up phase. In today's DI diesel and DI gasoline engines, auxiliary heating is essential to ensure thermal comfort, since fuel-efficient vehicles no longer transmit sufficient heat to the coolant. By modifying the internal engine combustion, which produces much higher exhaust temperatures, auxiliary heating by th exhaust heat can provide extremely high thermal output in conjunction with just a slight increase in fuel consumption. (orig.)

  17. Boosting devices with integral features for recirculating exhaust gas

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ko-Jen

    2015-12-22

    According to one embodiment of the invention, a turbine housing includes a turbine inlet in fluid communication with a turbine volute configured to house a turbine wheel, the turbine inlet configured to direct an exhaust gas flow from an engine to the turbine wheel. The turbine housing also includes a turbine outlet in fluid communication with the turbine volute, the turbine outlet configured to direct the exhaust gas flow to an exhaust gas conduit and a first exhaust gas recirculation supply port located on and in fluid communication with the turbine outlet, the first exhaust gas recirculation supply port being configured to direct a portion of the exhaust gas flow to an exhaust gas recirculation supply conduit.

  18. Exhaust gas recirculation in a homogeneous charge compression ignition engine

    Science.gov (United States)

    Duffy, Kevin P [Metamora, IL; Kieser, Andrew J [Morton, IL; Rodman, Anthony [Chillicothe, IL; Liechty, Michael P [Chillicothe, IL; Hergart, Carl-Anders [Peoria, IL; Hardy, William L [Peoria, IL

    2008-05-27

    A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

  19. Capture of Heat Energy from Diesel Engine Exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Chuen-Sen Lin

    2008-12-31

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

  20. Engine with exhaust gas recirculation system and variable geometry turbocharger

    Science.gov (United States)

    Keating, Edward J.

    2015-11-03

    An engine assembly includes an intake assembly, an internal combustion engine defining a plurality of cylinders and configured to combust a fuel and produce exhaust gas, and an exhaust assembly in fluid communication with a first subset of the plurality of cylinders. Each of the plurality of cylinders are provided in fluid communication with the intake assembly. The exhaust assembly is provided in fluid communication with a first subset of the plurality of cylinders, and a dedicated exhaust gas recirculation system in fluid communication with both a second subset of the plurality of cylinders and with the intake assembly. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the second subset of the plurality of cylinders to the intake assembly. Finally, the engine assembly includes a turbocharger having a variable geometry turbine in fluid communication with the exhaust assembly.

  1. Investigation of Diesel Exhaust Gas Toxicity on Transient Modes

    Directory of Open Access Journals (Sweden)

    Ivashchenko Nikolay Antonovich

    2014-12-01

    Full Text Available Currently, the generation of heat engines and their control systems are based on ecological indices such as the toxicity of the fulfilled gases. When designing motors, software packages are widely used. These software packages provide the ability to calculate the workflow of engine at steady-state conditions. The definition of indicators emissions is a difficult task. The distribution statistics of the modes shows that the engines of the transport units work on unsteady modes most of the time. The calculation of toxicity indicators is even less developed. In this article experimental and numeric study of the diesel engine with turbocharger exhaust toxicity was considered. As a result of the experimental study, which was conducted with single-cylinder diesel engine compartment simulated work on the transient state, working process characteristics of a diesel engine were obtained, including carbon and nitrogen oxides concentrations. Functional dependencies of concentrations of toxic exhaust components, such as carbon and nitrogen oxides, on excess air ratio and exhaust temperature were obtained. Diesel engine transient processes were simulated using developed mathematical dynamic model of combined engine in locomotive power plant with a change in control signal (position of locomotive driver’s controller and external influence signal (resistance moment. The analysis of exhaust gas toxicity was conducted.

  2. Effect of EGR on the exhaust gas temperature and exhaust opacity ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Hence, in order to meet the envi- ronmental legislations, it is highly desirable to reduce the amount of NOx in the exhaust gas. 275 .... (i) Hot EGR: Exhaust gas is recirculated without being cooled, resulting in increased intake ... is mounted on the inlet pipe between the air filter and the inlet manifold of the engine as shown in ...

  3. 46 CFR 63.25-7 - Exhaust gas boilers.

    Science.gov (United States)

    2010-10-01

    ... drum type exhaust gas steam boiler must have a feed water control system. The system must automatically... 46 Shipping 2 2010-10-01 2010-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS...

  4. 40 CFR 86.211-94 - Exhaust gas analytical system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas analytical system. 86.211-94 Section 86.211-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.211-94 Exhaust gas...

  5. Workshop on an Assessment of Gas-Side Fouling in Fossil Fuel Exhaust Environments

    Science.gov (United States)

    Marner, W. J. (Editor); Webb, R. L. (Editor)

    1982-01-01

    The state of the art of gas side fouling in fossil fuel exhaust environments was assessed. Heat recovery applications were emphasized. The deleterious effects of gas side fouling including increased energy consumption, increased material losses, and loss of production were identified.

  6. Boosting devices with integral features for recirculating exhaust gas

    Science.gov (United States)

    Wu, Ko -Jen

    2015-09-15

    According to one embodiment of the invention, a compressor housing includes a compressor inlet in fluid communication with a compressor volute configured to house a compressor wheel, the compressor inlet configured to provide a first air flow to the compressor wheel and a compressor outlet in fluid communication with the compressor volute, the compressor outlet configured to direct a compressed gas to an intake manifold. The compressor housing further includes an exhaust gas recirculation inlet port in fluid communication with the compressor volute, the exhaust gas recirculation inlet port being configured to combine an exhaust gas flow with the air flow to the compressor wheel.

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

    Directory of Open Access Journals (Sweden)

    Wail Aladayleh

    2015-01-01

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

  8. Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity

    Science.gov (United States)

    Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

    2002-01-01

    A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

  9. Thermoelectric generators incorporating phase-change materials for waste heat recovery from engine exhaust

    Science.gov (United States)

    Meisner, Gregory P; Yang, Jihui

    2014-02-11

    Thermoelectric devices, intended for placement in the exhaust of a hydrocarbon fuelled combustion device and particularly suited for use in the exhaust gas stream of an internal combustion engine propelling a vehicle, are described. Exhaust gas passing through the device is in thermal communication with one side of a thermoelectric module while the other side of the thermoelectric module is in thermal communication with a lower temperature environment. The heat extracted from the exhaust gasses is converted to electrical energy by the thermoelectric module. The performance of the generator is enhanced by thermally coupling the hot and cold junctions of the thermoelectric modules to phase-change materials which transform at a temperature compatible with the preferred operating temperatures of the thermoelectric modules. In a second embodiment, a plurality of thermoelectric modules, each with a preferred operating temperature and each with a uniquely-matched phase-change material may be used to compensate for the progressive lowering of the exhaust gas temperature as it traverses the length of the exhaust pipe.

  10. Development of heat-resistant cast steel for exhaust manifolds. Exhaust manifold yo tainetsu chuko no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ike, M.; Akiyama, K. (Nissan Motor Co. Ltd., Tokyo (Japan)); Otsuka, K.; Ito, K. (Hitachi Metals, Ltd., Tokyo (Japan))

    1991-07-01

    Any exhaust manifold is exposed to the severer thermal cycle condition by exhasut gas of the maximum temperature reaching near 1273K and therefore the thermal resistance reliability should be improved. A new cast heat resistant steel for the exhaust manifold which had better thermal fatigue resistance and oxidation resistance than conventional Ni-resist cast iron was developed this time. The developed material was based on the 18Cr ferritic heat resistant steel of low coefficent of thermal expansion and the oxidation resistance was improved, and further the thermal fatigue life was improved by aiming at the structural stability through elevating the transformation point to the upper limit of service temperature or more. These requirements were achieved by grasping the above mentioned characteristics of the part material and by studying the effect of main composing elements, C, N, Cr, Nb, Mo, on these characteristics. The cheaper exhaust manifold of higher thermal resistant reliability than conventional one could be put into practical use by using a newly developed casting process in addition to the use of this developed material. 7 refs., 11 figs., 5 tabs.

  11. Model Tests of Multiple Nozzle Exhaust Gas Eductor Systems for Gas Turbine Powered Ships

    Science.gov (United States)

    1977-06-01

    of Mechanical Engineering Dean of Science and Engineering 2 NAVAL POSTGRADUATE SCHOOL Monterey, California Rear Admiral Isham Linder J. R. Borsting...impingement on mast-mounted equipment within the exhaust gas plume and the infra-red signature of the hot exhaust gas. An effective means of reducing

  12. Considerations over the effects caused by a heat recovery system for exhaust gases, adapted to gas turbines originally designed for the operation in a simple cycle; Consideraciones sobre los efectos causados por un sistema de recuperacion de calor de gases de escape, adaptado a turbinas de gas disenadas originalmente para operar bajo un ciclo simple

    Energy Technology Data Exchange (ETDEWEB)

    Cuesta Escobar, Cesar A. [Instituto Mexicano del Petroleo, Mexico, D. F. (Mexico)

    1994-12-31

    This article sets out the considerations on what a heat recovery system from exhaust gases, to already installed and in operation gas turbines, and that were not originally designed to operate with this system, can cause. The potential effects are set forth on the control systems, on the combustion chambers, and in the gas turbine blades, utilized for natural gas pumping or power generation in land installations or in offshore platforms in trying to adapt to them a regenerative cycle or a heating system. Observed effects, fundamentally in the flame stability loop, flow velocity, thermal intensity coefficient, air/fuel relationships and mass flow. Also are presented the consequences that primary production system would suffer, mainly due to the natural gas pumping reduction, the space availability, the fuel consumption, and the maximum amount of heat susceptible to be recovered, comparing the requirements of this in the system. [Espanol] En este articulo se plantean las consideraciones sobre lo que puede provocar un sistema de recuperacion de calor de gases de escape adaptado a turbinas de gas ya instaladas, operando y que no fueron disenadas originalmente para operar con este sistema. Se plantean los probables efectos en los sistemas de control, en las camaras de combustion y en los empaletados de las turbinas de gas usadas para bombeo de gas natural o generacion electrica en instalaciones de tierra o plataformas marinas, al tratar de adaptarseles un ciclo regenerativo o un sistema para calentamiento. Efectos observados, fundamentalmente, en el LOOP de estabilidad de flama, velocidad del flujo, coeficiente de intensidad termica, relaciones aire-combustible y flujo masico. Tambien se presentan las consecuencias que sufriria el sistema primario de produccion debido, principalmente, a la reduccion del bombeo de gas natural, a la disponibilidad de espacio, al consumo de combustible y a la cantidad maxima de calor susceptible de recuperarse, comparada con los

  13. New catalysts for exhaust gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, M. [Kemira Metalkat Oy, Oulu (Finland)

    1996-12-31

    Major challenge for future catalyst systems was to develop thermally more stable washcoats for close coupled operating conditions and for engines operating under high speed and load conditions. To design these future emission systems extensive research and development was undertaken to develop methods to disperse and stabilize the key catalytic materials for operation at much higher temperatures. Second priority was to design catalysts that are more effective under low temperature exhaust conditions and have improved oxygen storage properties in the washcoats. Incorporating new materials and modified preparation technology a new generation of metallic catalyst formulations emerged, those being trimetallic K6 (Pt:Pd:Rh and bimetallic K7) (Pd+Pd:Rh). The target was to combine the best property of Pt:Rh (good NO{sub x} reduction) with that of the good HC oxidation activity of Pd and to ensure that precious metal/support interactions were positively maintained. Both K6 and K7 concepts contain special catalyst structures with optimized washcoat performance which can be brick converter configuration. Improvement in light-off, thermal stability and transient performance with these new catalyst formulations have clearly been shown in both laboratory and vehicle testing. (author) (20 refs.)

  14. 30 CFR 36.26 - Composition of exhaust gas.

    Science.gov (United States)

    2010-07-01

    ... immediately at full load and speed. The preliminary liquid-fuel-injection rate shall be such that the exhaust... Investigation has shown that for practical purposes, Pittsburgh natural gas (containing a high percentage of..., or torque converters ordinarily are not required in the coupling train. ...

  15. IC ENGINE SUPERCHARGING AND EXHAUST GAS RECIRCULATION USING JET COMPRESSOR

    Directory of Open Access Journals (Sweden)

    Adhimoulame Kalaisselvane

    2010-01-01

    Full Text Available Supercharging is a process which is used to improve the performance of an engine by increasing the specific power output whereas exhaust gas recirculation reduces the NOx produced by engine because of supercharging. In a conventional engine, supercharger functions as a compressor for the forced induction of the charge taking mechanical power from the engine crankshaft. In this study, supercharging is achieved using a jet compressor. In the jet compressor, the exhaust gas is used as the motive stream and the atmospheric air as the propelled stream. When high pressure motive stream from the engine exhaust is expanded in the nozzle, a low pressure is created at the nozzle exit. Due to this low pressure, atmospheric air is sucked into the expansion chamber of the compressor, where it is mixed and pressurized with the motive stream. The pressure of the mixed stream is further increased in the diverging section of the jet compressor. A percentage volume of the pressurized air mixture is then inducted back into the engine as supercharged air and the balance is let out as exhaust. This process not only saves the mechanical power required for supercharging but also dilutes the constituents of the engine exhaust gas thereby reducing the emission and the noise level generated from the engine exhaust. The geometrical design parameters of the jet compressor were obtained by solving the governing equations using the method of constant rate of momentum change. Using the theoretical design parameters of the jet compressor, a computational fluid dinamics analysis using FLUENT software was made to evaluate the performance of the jet compressor for the application of supercharging an IC engine. This evaluation turned out to be an efficient diagnostic tool for determining performance optimization and design of the jet compressor. A jet compressor was also fabricated for the application of supercharging and its performance was studied.

  16. Experimental study on exhaust gas after treatment using limestone

    Directory of Open Access Journals (Sweden)

    Sakhrieh Ahmad

    2013-01-01

    Full Text Available In this study a simple low-cost exhaust gas after-treatment filter using limestone was developed and tested on a four cylinder DI diesel engine coupled with dynamometer under variable engine running conditions. Limestone was placed in cast iron housing through which exhaust gases passes. The concentration of both carbon dioxide and nitrogen oxides were measured with and without the filter in place. It was found that both pollutants were decreased significantly when the filter is in place, with no increase in the fuel consumption rate.

  17. Natural gas vs. heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Verrips, A.M.; Canney, W.A.

    Spokesmen for gas and electric utilities describe the relative merits of using natural gas and electric heat pumps. Both argue that their product is more economical and operates more efficiently than its competitor. Rising natural gas prices are responsible for making costs more competitive, although rates for both gas and electricity vary by region. The utilities also describe heat pump advantages in terms of installation ease and cost, reliability, maintenance, and thermal comfort. Both provide documentation to support their claims. 2 tables.

  18. Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine

    Science.gov (United States)

    Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

    2014-05-13

    A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

  19. 30 CFR 36.43 - Determination of exhaust-gas composition.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Determination of exhaust-gas composition. 36.43... TRANSPORTATION EQUIPMENT Test Requirements § 36.43 Determination of exhaust-gas composition. (a) Samples shall be taken to determine the composition of the exhaust gas while the engine is operated at loads and speeds...

  20. Vehicle exhaust gas chemical sensors using acoustic wave resonators

    Energy Technology Data Exchange (ETDEWEB)

    Cernosek, R.W.; Small, J.H.; Sawyer, P.S.; Bigbie, J.R. [Sandia National Labs., Albuquerque, NM (United States); Anderson, M.T. [3M Industrial and Consumer Sector Research Lab., St. Paul, MN (United States)

    1998-03-01

    Under Sandia`s Laboratory Directed Research and Development (LDRD) program, novel acoustic wave-based sensors were explored for detecting gaseous chemical species in vehicle exhaust streams. The need exists for on-line, real-time monitors to continuously analyze the toxic exhaust gases -- nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons (HC) -- for determining catalytic converter efficiency, documenting compliance to emission regulations, and optimizing engine performance through feedback control. In this project, the authors adapted existing acoustic wave chemical sensor technology to the high temperature environment and investigated new robust sensor materials for improving gas detection sensitivity and selectivity. This report describes one new sensor that has potential use as an exhaust stream residual hydrocarbon monitor. The sensor consists of a thickness shear mode (TSM) quartz resonator coated with a thin mesoporous silica layer ion-exchanged with palladium ions. When operated at temperatures above 300 C, the high surface area film catalyzes the combustion of the hydrocarbon vapors in the presence of oxygen. The sensor acts as a calorimeter as the exothermic reaction slightly increases the temperature, stressing the sensor surface, and producing a measurable deviation in the resonator frequency. Sensitivities as high as 0.44 (ppm-{Delta}f) and (ppm-gas) have been measured for propylene gas, with minimum detectable signals of < 50 ppm of propylene at 500 C.

  1. A review on waste heat recovery from exhaust in the ceramics industry

    Science.gov (United States)

    Delpech, Bertrand; Axcell, Brian; Jouhara, Hussam

    2017-11-01

    Following the energy crisis in 1980, many saving technologies have been investigated with attempts to implement them into various industries, one of them is the field of ceramic production. In order to comply with energy saving trends and environmental issues, the European ceramic industry sector has developed energy efficient systems which reduced significantly production time and costs and reduced total energy consumption. The last achievement is of great importance as the energy consumption of the ceramic process accounts for a significant percentage of the total production costs. More precisely, the firing stage consumes the highest amount of energy during the whole ceramic production process. The use of roller kilns, fired by natural gas, involves a loss of 50% of the input energy via the flue gas and the cooling gas exhausts. This review paper briefly describes the production process of the different ceramic products, with a focus on the ceramic sector in Europe. Due to the limited on waste heat recovery in the ceramic industry, other high temperature waste heat recovery applications are considered in the paper, such as in concrete and steel production, which could have a potential use in the ceramic industry. The state of the art technologies used in the ceramics industry are reviewed with a special interest in waste heat recovery from the ceramic process exhaust stacks and energy saving technologies.

  2. Study on direct measurement of diesel exhaust gas flow rate. Development of ultrasonic exhaust gas flowmeter; Diesel hai gas ryuryo no chokusetsu sokuteiho ni kansuru kenkyu. Choonpa hai gas ryuryokeino kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, A.; Takamoto, M.; Yamzaki, H. [National Research Laboratory of Meteology, Tsukuba (Japan); Hosoi, K. [Japan Automobile Research Institute Inc., Tsukuba (Japan); Arai, S.; Shimizu, K. [Kaijo Corp., Tokyo (Japan)

    2000-02-25

    The partial flow dilution method is one of the typical measurement methods for particulate matter emission from diesel engines. In this method, exhaust gas at a transient flow rate should be transferred to a dilution tunnel at a constant ratio of exhaust gas. The present partial flow dilution method is used under steady-state engine operating conditions in lieu of direct flow rate measurement of exhaust gas. A more practical control of exhaust emission is, however, required world widely; therefore development of an exhaust gas flowmeter is indispensable in the partial flow dilution method for transient engine operating conditions. An ultrasonic exhaust gas flowmeter has been developed and been demonstrated to be capable of measuring the exhaust gas flow rate with sufficient accuracy. (author)

  3. Exhaust gas bypass valve control for thermoelectric generator

    Science.gov (United States)

    Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter Jacobus; Anderson, Todd Alan

    2012-09-04

    A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

  4. The American football uniform: uncompensable heat stress and hyperthermic exhaustion.

    Science.gov (United States)

    Armstrong, Lawrence E; Johnson, Evan C; Casa, Douglas J; Ganio, Matthew S; McDermott, Brendon P; Yamamoto, Linda M; Lopez, Rebecca M; Emmanuel, Holly

    2010-01-01

    In hot environments, the American football uniform predisposes athletes to exertional heat exhaustion or exercise-induced hyperthermia at the threshold for heat stroke (rectal temperature [T(re)] > 39 degrees C). To evaluate the differential effects of 2 American football uniform configurations on exercise, thermal, cardiovascular, hematologic, and perceptual responses in a hot, humid environment. Randomized controlled trial. Human Performance Laboratory. Ten men with more than 3 years of competitive experience as football linemen (age = 23.8 +/- 4.3 years, height = 183.9 +/- 6.3 cm, mass = 117.41 +/- 12.59 kg, body fat = 30.1% +/- 5.5%). Participants completed 3 controlled exercise protocols consisting of repetitive box lifting (lifting, carrying, and depositing a 20.4-kg box at a rate of 10 lifts per minute for 10 minutes), seated recovery (10 minutes), and up to 60 minutes of treadmill walking. They wore one of the following: a partial uniform (PART) that included the National Football League (NFL) uniform without a helmet and shoulder pads; a full uniform (FULL) that included the full NFL uniform; or control clothing (CON) that included socks, sneakers, and shorts. Exercise, meals, and hydration status were controlled. We assessed sweat rate, T(re), heart rate, blood pressure, treadmill exercise time, perceptual measurements, plasma volume, plasma lactate, plasma glucose, plasma osmolality, body mass, and fat mass. During 19 of 30 experiments, participants halted exercise as a result of volitional exhaustion. Mean sweat rate, T(re), heart rate, and treadmill exercise time during the CON condition were different from those measures during the PART (P range, .04-.001; d range, 0.42-0.92) and FULL (P range, .04-.003; d range, 1.04-1.17) conditions; no differences were detected for perceptual measurements, plasma volume, plasma lactate, plasma glucose, or plasma osmolality. Exhaustion occurred during the FULL and PART conditions at the same T(re) (39.2 degrees C

  5. Model of Heat Exchangers for Waste Heat Recovery from Diesel Engine Exhaust for Thermoelectric Power Generation

    Science.gov (United States)

    Baker, Chad; Vuppuluri, Prem; Shi, Li; Hall, Matthew

    2012-06-01

    The performance and operating characteristics of a hypothetical thermoelectric generator system designed to extract waste heat from the exhaust of a medium-duty turbocharged diesel engine were modeled. The finite-difference model consisted of two integrated submodels: a heat exchanger model and a thermoelectric device model. The heat exchanger model specified a rectangular cross-sectional geometry with liquid coolant on the cold side, and accounted for the difference between the heat transfer rate from the exhaust and that to the coolant. With the spatial variation of the thermoelectric properties accounted for, the thermoelectric device model calculated the hot-side and cold-side heat flux for the temperature boundary conditions given for the thermoelectric elements, iterating until temperature and heat flux boundary conditions satisfied the convection conditions for both exhaust and coolant, and heat transfer in the thermoelectric device. A downhill simplex method was used to optimize the parameters that affected the electrical power output, including the thermoelectric leg height, thermoelectric n-type to p-type leg area ratio, thermoelectric leg area to void area ratio, load electrical resistance, exhaust duct height, coolant duct height, fin spacing in the exhaust duct, location in the engine exhaust system, and number of flow paths within the constrained package volume. The calculation results showed that the configuration with 32 straight fins was optimal across the 30-cm-wide duct for the case of a single duct with total height of 5.5 cm. In addition, three counterflow parallel ducts or flow paths were found to be an optimum number for the given size constraint of 5.5 cm total height, and parallel ducts with counterflow were a better configuration than serpentine flow. Based on the reported thermoelectric properties of MnSi1.75 and Mg2Si0.5Sn0.5, the maximum net electrical power achieved for the three parallel flow paths in a counterflow arrangement was 1

  6. Experimental investigation of an improved exhaust recovery system for liquid petroleum gas fueled spark ignition engine

    Directory of Open Access Journals (Sweden)

    Gürbüz Habib

    2015-01-01

    Full Text Available In this study, we have investigated the recovery of energy lost as waste heat from exhaust gas and engine coolant, using an improved thermoelectric generator (TEG in a LPG fueled SI engine. For this purpose, we have designed and manufactured a 5-layer heat exchanger from aluminum sheet. Electrical energy generated by the TEG was then used to produce hydrogen in a PEM water electrolyzer. The experiment was conducted at a stoichiometric mixture ratio, 1/2 throttle position and six different engine speeds at 1800-4000 rpm. The results of this study show that the configuration of 5-layer counterflow produce a higher TEG output power than 5-layer parallel flow and 3-layer counterflow. The TEG produced a maximum power of 63.18 W when used in a 5-layer counter flow configuration. This resulted in an improved engine performance, reduced exhaust emission as well as an increased engine speed when LPG fueled SI engine is enriched with hydrogen produced by the PEM electrolyser supported by TEG. Also, the need to use an extra evaporator for the LPG fueled SI engine is eliminated as LPG heat exchangers are added to the fuel line. It can be concluded that an improved exhaust recovery system for automobiles can be developed by incorporating a PEM electrolyser, however at the expense of increasing costs.

  7. Apparatus and methods of reheating gas turbine cooling steam and high pressure steam turbine exhaust in a combined cycle power generating system

    Science.gov (United States)

    Tomlinson, Leroy Omar; Smith, Raub Warfield

    2002-01-01

    In a combined cycle system having a multi-pressure heat recovery steam generator, a gas turbine and steam turbine, steam for cooling gas turbine components is supplied from the intermediate pressure section of the heat recovery steam generator supplemented by a portion of the steam exhausting from the HP section of the steam turbine, steam from the gas turbine cooling cycle and the exhaust from the HP section of the steam turbine are combined for flow through a reheat section of the HRSG. The reheated steam is supplied to the IP section inlet of the steam turbine. Thus, where gas turbine cooling steam temperature is lower than optimum, a net improvement in performance is achieved by flowing the cooling steam exhausting from the gas turbine and the exhaust steam from the high pressure section of the steam turbine in series through the reheater of the HRSG for applying steam at optimum temperature to the IP section of the steam turbine.

  8. Experimental analysis of diffusion absorption refrigerator driven by electrical heater and engine exhaust gas

    Directory of Open Access Journals (Sweden)

    Mohamed Izzedine Serge ADJIBADE

    2017-09-01

    Full Text Available This work presents an experimental study of H20-NH3-H2 diffusion absorption refrigeration under two types of energy sources, i.e. the conventional electric energy from grid (electric and exhaust gas from internal combustion engine. Dynamic method is used to evaluate the behavior of the components of the system for both energy sources. Results obtained show that the performance of each component under different types of energy sources is almost coherent. For the generator, the electrical heater system requires more time to warm up, around three minutes, compared to the 40 s for system running with exhaust gas. For the evaporator, the decreasing rate is higher for the exhaust gas source and it took only about two hours to reach steady-state while for the electrical heat, the steady-state is reached after about seven hours of operation. For both energy sources, the evaporation temperature stabilizes to 3 °C and the minimum temperature to boil off ammonia is around 140 °C.

  9. Numerical study of finned type heat exchangers for ICEs exhaust waste heat recovery

    Directory of Open Access Journals (Sweden)

    M. Hatami

    2014-11-01

    Full Text Available In this paper, two cases of heat exchangers (HEXs which previously were used in exhaust of internal combustion engines (ICEs are modeled numerically to recover the exhaust waste heat. It is tried to find the best viscous model to obtain the results with more accordance by experimental results. One of the HEXs is used in a compression ignition (CI engine with water as cold fluid and other is used in a spark ignition (SI engine with a mixture of 50% water and 50% ethylene glycol as cold fluid. As a main outcome, SST k–ω and RNG k–ε are suitable viscous models for these kinds of problems. Also, effect sizes and numbers of fins on recovered heat amount are investigated in various engine loads and speeds.

  10. A miniswine model of acute exertional heat exhaustion.

    Science.gov (United States)

    Gentile, B J; Szlyk-Modrow, P C; Durkot, M J; Krestel, B A; Sils, I V; Tartarini, K A; Alkhyyat, A M

    1996-06-01

    We examined the thermoregulatory and hemodynamic responses of 12 miniswine (31 +/- 3.9 kg) during 25-30 min of treadmill exercise (5.4 km.h-1, 5% grade) under cool (10 degrees C), moderate (20 degrees C) and warm (30 degrees C) ambient temperature (Ta) conditions. Within 15-20 min of exercise at Ta = 30 degrees C, the miniswine demonstrated significant hyperventilation, hypersalivation, and unsteady gait. Exercise-heat endurance time (T) at Ta = 30 degrees C decreased by 35% and 40% in comparison to T at Ta = 20 degrees C and 10 degrees C, respectively. This resulted from a significant rise in heat strain (S)-defined as the rate of change in rectal temperature. Averaged throughout exercise, S increased from 0.04 +/- 0.01 degree C.min-1 and 0.05 +/- 0.02 degree C.min-1 at Ta = 10 degrees C and 20 degrees C, respectively, to 0.10 +/- 0.03 degree C.min-1 at Ta = 30 degrees C. Due to the comparatively large storage capacity of the porcine spleen relative to humans, splenectomized miniswine were used. This permitted calculation of percentage changes in plasma volume (% delta PVc) from hematocrit (HCT) and hemoglobin (HGB) without the confounding effects of splenic red cells released into the circulation during exercise. Independent of Ta, pre-exercise PVc decreased 3%-5% (p post-exercise. We conclude that the poor thermoregulatory ability of miniswine manifested in insignificant sweating and restricted evaporative cooling, may make them an appropriate model for acute exertional heat exhaustion in humans working in hot, humid conditions and/or wearing impermeable protective clothing. Further, evaluation of plasma volume changes from HCT and HGB in a miniswine model should consider the merit of a splenectomized design.

  11. An experimental study on the effects of exhaust gas on spruce (Picea abies L. Karst.)

    Energy Technology Data Exchange (ETDEWEB)

    Hautala, E.L.; Holopainen, J.; Kaerenlampi, L. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Surakka, J.; Ruuskanen, J. [Kuopio Univ. (Finland). Dept. of Environmental Sciences

    1995-12-31

    Motor vehicle exhausts are significant contributors to air pollution. Besides fine particles and inorganic gases, like CO, SO{sub 2} and NO{sub x}, exhaust gas contains a large group of aromatic hydrocarbon compounds, many of which are phytotoxic. In field studies, exhausts are found to have both direct and indirect harmful effects on roadside plants. However, only few experimental studies have been made about the effects of exhaust gas emissions on coniferous trees. The aim of this study was to survey the effects of exhausts on spruce (Picea abies L. Karst.) in standardized conditions. The concentrations of major exhaust gas components in the chamber atmosphere were detected simultaneously. The effects of exhaust on epistomatal waxes of first-year spruce needles are described. (author)

  12. 40 CFR 86.111-90 - Exhaust gas analytical system.

    Science.gov (United States)

    2010-07-01

    ... and carbon dioxide and a chemiluminescence analyzer (CL) for the determination of oxides of nitrogen... mixture of 3 percent CO2 in N2 which has been bubbled through water at room temperature produces an... and filter shall be heated to maintain a sample gas temperature of 375°±10 °F (191°±6 °C) before the...

  13. Exhaust Gas Recirculation Control for Large Diesel Engines - Achievable Performance with SISO Design

    DEFF Research Database (Denmark)

    Hansen, Jakob Mahler; Blanke, Mogens; Niemann, Hans Henrik

    2013-01-01

    This paper investigates control possibilities for Exhaust Gas Recirculation (EGR) on large diesel engines. The goal is to reduce the amount of NOx in the exhaust gas by reducing the oxygen concentration available for combustion. Control limitations imposed by the system are assessed using linear ...... Feedback Theory (QFT) designs. Validation of the controller is made on the model with focus on disturbance reduction ability....

  14. 30 CFR 36.47 - Tests of exhaust-gas cooling system.

    Science.gov (United States)

    2010-07-01

    ... at the final temperature. Water in excess of that required for adiabatic saturation shall be... before the exhaust gas is diluted with air, shall not exceed 170 °F. or the temperature of adiabatic saturation, if this temperature is lower. (d) Water consumed in cooling the exhaust gas under the test...

  15. Exhaust Gas Temperature Measurements in Diagnostics of Turbocharged Marine Internal Combustion Engines Part II Dynamic Measurements

    Directory of Open Access Journals (Sweden)

    Korczewski Zbigniew

    2016-01-01

    Full Text Available The second part of the article describes the technology of marine engine diagnostics making use of dynamic measurements of the exhaust gas temperature. Little-known achievements of Prof. S. Rutkowski of the Naval College in Gdynia (now: Polish Naval Academy in this area are presented. A novel approach is proposed which consists in the use of the measured exhaust gas temperature dynamics for qualitative and quantitative assessment of the enthalpy flux of successive pressure pulses of the exhaust gas supplying the marine engine turbocompressor. General design assumptions are presented for the measuring and diagnostic system which makes use of a sheathed thermocouple installed in the engine exhaust gas manifold. The corrected thermal inertia of the thermocouple enables to reproduce a real time-history of exhaust gas temperature changes.

  16. Parametric study on ship’s exhaust-gas behavior using computational fluid dynamics

    Directory of Open Access Journals (Sweden)

    Sunho Park

    2017-01-01

    Full Text Available The influence of design parameters related to a ship’s exhaust-gas behavior was investigated using computational fluid dynamics (CFD for an 8,000 TEU container carrier. To verify the numerical methods, the results were studied by comparing with experimental results. Several test conditions, i.e. various load conditions of ship, wind angle, deckhouse breadth, radar mast height, and exhaust-pipe height and shape were considered for a ship’s exhaust gas flow around the 8,000 TEU container carrier. The influence of the design parameters on contamination by the exhaust gas was quantified, after which the principal parameters to avoid contamination were selected. Finally, the design guideline of yP/H = 2 was suggested to avoid the contamination from the ship’s exhaust gas using the CFD results, model tests, and sea trials.

  17. Real-time exhaust gas modular flowmeter and emissions reporting system for mobile apparatus

    Science.gov (United States)

    Breton, Leo Alphonse Gerard (Inventor)

    2002-01-01

    A real-time emissions reporting system includes an instrument module adapted to be detachably connected to the exhaust pipe of a combustion engine to provide for flow of exhaust gas therethrough. The instrument module includes a differential pressure probe which allows for determination of flow rate of the exhaust gas and a gas sampling tube for continuously feeding a sample of the exhaust gas to a gas analyzer or a mounting location for a non-sampling gas analyzer. In addition to the module, the emissions reporting system also includes an elastomeric boot for detachably connecting the module to the exhaust pipe of the combustion engine, a gas analyzer for receiving and analyzing gases sampled within the module and a computer for calculating pollutant mass flow rates based on concentrations detected by the gas analyzer and the detected flowrate of the exhaust gas. The system may also include a particulate matter detector with a second gas sampling tube feeding same mounted within the instrument module.

  18. Combined particle emission reduction and heat recovery from combustion exhaust - A novel approach for small wood-fired appliances

    Energy Technology Data Exchange (ETDEWEB)

    Messerer, A.; Poeschl, U.; Niessner, R. [Technical University of Munich, Munich (Germany). Institute of Hydrochemistry; Schmatloch, V. [EMPA, Swiss Federal Institute for Materials Research and Testing, Duebendorf (Switzerland)

    2007-07-15

    Replacing fossil fuels by renewable sources of energy is one approach to address the problem of global warming due to anthropogenic emissions of greenhouse gases. Wood combustion can help to replace fuel oil or gas. It is advisable, however, to use modern technology for combustion and exhaust gas after-treatment in order to achieve best efficiency and avoid air quality problems due to high emission levels often related to small scale wood combustion. In this study, simultaneous combustion particle deposition and heat recovery from the exhaust of two commercially available wood-fired appliances has been investigated. The experiments were performed with a miniature pipe bundle heat exchanger operating in the exhaust gas lines of a fully automated pellet burner or a closed fireplace. The system has been characterised for a wide range of aerosol inlet temperatures (135-295 {sup circle} C) and flow velocities (0.13-1.0ms{sup -1}), and particle deposition efficiencies up to 95% have been achieved. Deposition was dominated by thermophoresis and diffusion and increased with the average temperature difference and retention time in the heat exchanger. The aerosols from the two different appliances exhibited different deposition characteristics, which can be attributed to enhanced deposition of the nucleation mode particles generated in the closed fire place. The measured deposition efficiencies can be described by simple linear parameterisations derived from laboratory studies. The results of this study demonstrate the feasibility of thermophoretic particle removal from biomass burning flue gas and support the development of modified heat exchanger systems with enhanced capability for simultaneous heat recovery and particle deposition. (author)

  19. Simulation and experimental study on thermal optimization of the heat exchanger for automotive exhaust-based thermoelectric generators

    Directory of Open Access Journals (Sweden)

    C.Q. Su

    2014-11-01

    Full Text Available Thermoelectric technology has revealed the potential for automotive exhaust-based thermoelectric generator (TEG, which contributes to the improvement of the fuel economy of the engine-powered vehicle. As a major factor, thermal capacity and heat transfer of the heat exchanger affect the performance of TEG effectively. With the thermal energy of exhaust gas harvested by thermoelectric modules, a temperature gradient appears on the heat exchanger surface, so as the interior flow distribution of the heat exchanger. In order to achieve uniform temperature distribution and higher interface temperature, the thermal characteristics of heat exchangers with various heat transfer enhancement features are studied, such as internal structure, material and surface area. Combining the computational fluid dynamics simulations and infrared test on a high-performance engine with a dynamometer, the thermal performance of the heat exchanger is evaluated. Simulation and experiment results show that a plate-shaped heat exchanger made of brass with accordion-shaped internal structure achieves a relatively ideal performance, which can practically improve overall thermal performance of the TEG.

  20. Portable Gas Analyzer Based on Fourier Transform Infrared Spectrometer for Patrolling and Examining Gas Exhaust

    Directory of Open Access Journals (Sweden)

    Yuntao Liang

    2015-01-01

    Full Text Available Aimed at monitoring emission of organic gases such as CH4, C2H6, C3H8, iso-C4H10, n-C4H10, C2H4, C3H6, C2H2, CO, and CO2, from coal mines, petroleum refineries, and other plants, a Fourier Transform Infrared (FT-IR spectrometer was used to develop a portable gas analyzer for patrolling and examining gas exhaust. Firstly, structure of the instrument was introduced. Then, a spectral analysis approach was presented. Finally, instrument was tested with standard gases and with actual gases emitted from a petroleum refinery. For the latter test, a gas chromatograph (GC was used as a reference instrument. The test results showed that the detection limit of every component of analyte was less than 10 × 10−6. The maximum test error of every analyte was less than 15 × 10−6 when its practical concentration was no more than 500 × 10−6. A final comparison showed that the result curves of analytes obtained with FT-IR spectrometer almost overlapped with those obtained with GC, and their resulting noise was less than 6.4% when the practical gas concentration was above 100 × 10−6. As a result, our instrument was suitable to be used as a portable instrument for monitoring exhaust gases.

  1. 40 CFR 86.1310-90 - Exhaust gas sampling and analytical system; diesel engines.

    Science.gov (United States)

    2010-07-01

    ... system; diesel engines. 86.1310-90 Section 86.1310-90 Protection of Environment ENVIRONMENTAL PROTECTION... ENGINES (CONTINUED) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1310-90 Exhaust gas sampling and analytical system; diesel engines...

  2. A Preliminary Study on Designing and Testing of an Absorption Refrigeration Cycle Powered by Exhaust Gas of Combustion Engine

    Science.gov (United States)

    Napitupulu, F. H.; Daulay, F. A.; Dedy, P. M.; Denis; Jecson

    2017-03-01

    In order to recover the waste heat from the exhaust gas of a combustion engine, an adsorption refrigeration cycle is proposed. This is a preliminary study on design and testing of a prototype of absorption refrigeration cycle powered by an internal combustion engine. The heat source of the cycle is a compression ignition engine which generates 122.36 W of heat in generator of the cycle. The pairs of absorbent and refrigerant are water and ammonia. Here the generator is made of a shell and tube heat exchanger with number of tube and its length are 20 and 0.69 m, respectively. In the experiments the exhaust gas, with a mass flow rate of 0.00016 kg/s, enters the generator at 110°C and leaves it at 72°C. Here, the solution is heated from 30°C to 90°C. In the evaporator, the lowest temperature can be reached is 17.9°C and COP of the system is 0.45. The main conclusion can be drawn here is that the proposed system can be used to recycle the waste heat and produced cooling. However, the COP is still low.

  3. Possibilities of optimum fuel utilization. Utilization of the useful heat in gas-fired heat generators

    Energy Technology Data Exchange (ETDEWEB)

    Rado, L. (Ruhrgas A.G., Essen (Germany, F.R.))

    1976-06-01

    A report is given on a process which permits complete or at least substantial utilization of the upper calorific value of a fuel. This happens by cooling the exhaust gases in an additional appliance connected with the outlet side of the actual boiler, so that most of the sensible heat from the exhaust gases can be used. In addition, the condensation heat of the steam can be utilized by separating this steam contained in the exhaust gas. The lower part of the appliance is constructed as a condensation storage tank with an overflow. The exhaust gases leaving the heat generator are passed into the appliance and cooled in water trickling down in counter-current direction. With the aid of the research carried out and a calculation of economy, it is shown that, considering the present-day state of engineering, the additional appliance can profitably be introduced if the output of the heat generator for the apparatus is greater than 0.2 Gcal/h.

  4. Effect of EGR on the exhaust gas temperature and exhaust opacity ...

    Indian Academy of Sciences (India)

    In diesel engines, NOx formation is a highly temperature-dependent phenomenon and takes place when the temperature in the combustion chamber exceeds 2000 K. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control. One simple way of ...

  5. In optics humidity compensation in NDIR exhaust gas measurements of NO2

    DEFF Research Database (Denmark)

    Stolberg-Rohr, Thomine Kirstine; Buchner, Rainer; Clausen, Sønnik

    2015-01-01

    NDIR is proposed for monitoring of air pollutants emitted by ship engines. Careful optical filtering overcomes the challenge of optical detection of NO2 in humid exhaust gas, despite spectroscopic overlap with the water vapour band. © 2014 OSA.......NDIR is proposed for monitoring of air pollutants emitted by ship engines. Careful optical filtering overcomes the challenge of optical detection of NO2 in humid exhaust gas, despite spectroscopic overlap with the water vapour band. © 2014 OSA....

  6. Nonlinear Adaptive Control of Exhaust Gas Recirculation for Large Diesel Engines

    DEFF Research Database (Denmark)

    Nielsen, Kræn Vodder; Blanke, Mogens; Vejlgaard-Laursen, Morten

    2015-01-01

    A nonlinear adaptive controller is proposed for the exhaust gas recirculation systemon large two-stroke diesel engines. The control design is based on a control oriented model ofthe nonlinear dynamics at hand that incorporates load and engine speed changes as knowndisturbances to the exhaust gas...... will make the system converge exponentiallyto the best achievable state. Simulation examples confirm convergence and good disturbancerejection over relevant operational ranges of the engine....

  7. Efficiency of thermoelectric recuperators of the exhaust gas energy of internal combustion engines

    Science.gov (United States)

    Anatychuk, L. I.; Kuz, R. V.; Rozver, Yu. Yu.

    2012-06-01

    Results of computer simulation of thermoelectric generators (TEG) using the exhaust heat of internal combustion engines are presented. Sectionalized generator schematics whereby maximum efficiency is achieved for cases of real temperature dependences of the most suitable thermoelectric materials are considered. A model optimized for minimum cost is considered as well. Results of experimental research on generator that employs exhaust heat from heat and electricity cogeneration plant with a diesel engine are presented. Computer simulation is verified by the test results. The outlook for application of such heat recuperators in stationary plants is considered.

  8. NOx Monitoring in Humid Exhaust Gas Using Non-Dispersive Infrared Spectroscopy

    DEFF Research Database (Denmark)

    Stolberg-Rohr, Thomine Kirstine

    This PhD thesis is concerned with the measurement of NOX in moist exhaust gas onboard ships using non-dispersive infrared (NDIR) spectroscopy. In such a measurement one of the major challenges is spectral interference from water vapour which is present in high concentrations in the exhaust. The Ph...... suggesting that it is possible but challenging to measure NOX in moist exhaust gas using NDIR. The characteristics of optical filters tend to change with temperature, and since this compromises the water signal balancing, much of the work presented in the thesis is devoted to the design of optical bandpass...

  9. Radiation from Rocket Exhaust Plumes. Part 1; Inhomogeneous Radiant Heat Transfer from Saturn Type Rocket Exhaust Plumes

    Science.gov (United States)

    Huffaker, Robert M.; Carlson, Donald J.

    1966-01-01

    A radiant heat transfer computer program has been developed by R-AERO-A to calculate radiation from inhomogeneous gases prevalent in Saturn-type exhaust plumes. The radiating species considered in this computer program are water vapor, carbon dioxide, carbon monoxide and carbon particles. The infrared spectral absorption characteristics of these species have been determined under NASA contract. Band model parameters have been used to represent the infrared spectral absorption coefficients over 25 cm-I increments. A modified Curtis-Goodson approximation is used in the inhomogeneous heat transfer calculation. This has been shown to give satisfactory results over the temperature and pressure range of interest in Saturn exhaust plumes. Results are shown for the Saturn-type engines for specific flow field assumptions. Some comparison with experimental spectroscopic data will also be presented. The effect of wavelength increment, field of view, and distance increment along the line of sight on the heat transfer will be discussed. Computer techniques for minimum computer time in calculating radiation from a three-dimensional flow field will also be outlined.

  10. Exhaust gas purification with sodium bicarbonate. Analysis and evaluation; Abgasreinigung mit Natriumhydrogencarbonat. Analyse und Bewertung

    Energy Technology Data Exchange (ETDEWEB)

    Quicker, Peter; Rotheut, Martin; Schulten, Marc [RWTH Aachen Univ. (Germany). Lehr- und Forschungsgebiet Technologie der Energierohstoffe (TEER); Athmann, Uwe [dezentec ingenieurgesellschaft mbH, Essen (Germany)

    2013-03-01

    The dry exhaust gas cleaning uses sodium bicarbonate in order to absorb acid components of exhaust gases such as sulphur dioxide or hydrochloric acid. Recently, sodium and calcium based adsorbents are compared with respect to their economic and ecologic options. None of the investigations performed considered decidedly practical experiences from the system operation such as differences in the management, availability, personnel expenditure and maintenance expenditure. Under this aspect, the authors of the contribution under consideration report on exhaust gas cleaning systems using sodium carbonate as well as lime adsorbents. The operators of these exhaust gas cleaning systems were questioned on their experiences, and all relevant operational data (consumption of additives, consumption of energy, emissions, standstill, maintenance effort) were recorded and evaluated at a very detailed level.

  11. Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow

    Science.gov (United States)

    Orosa, John

    2014-03-11

    An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

  12. Current Techniques of Growing Algae Using Flue Gas from Exhaust Gas Industry: a Review.

    Science.gov (United States)

    Huang, Guanhua; Chen, Feng; Kuang, Yali; He, Huan; Qin, An

    2016-03-01

    The soaring increase of flue gas emission had caused global warming, environmental pollution as well as climate change. Widespread concern on reduction of flue gas released from industrial plants had considered the microalgae as excellent biological materials for recycling the carbon dioxide directly emitted from exhaust industries. Microalgae also have the potential to be the valuable feedback for renewable energy production due to their high growth rate and abilities to sequester inorganic carbon through photosynthetic process. In this review article, we will illustrate important relative mechanisms in the metabolic processes of biofixation by microalgae and their recent experimental researches and advances of sequestration of carbon dioxide by microalgae on actual industrial and stimulate flue gases, novel photobioreactor cultivation systems as well as the perspectives and limitations of microalgal cultivation in further development.

  13. Modelling and Operation of Diesel Engine Exhaust Gas Cleaning Systems

    DEFF Research Database (Denmark)

    Åberg, Andreas

    Diesel engine exhaust gases contain several harmful substances. The main pollutants are carbon monoxide (CO), hydrocarbons (HC), particulate matter (PM), and nitrous gases such as nitrogen oxide (NO) and nitrogen dioxide (NO2) (together NOx). Reducing the emission of these pollutants is of great...... outperformed the other control structures. The results were experimentally verified by implementing the tested controllers on a full-scale engine setup, and the results showed that coupling feedback with ANR based feedforward was yielding better performance. The PD controller showed good performance...... importance due to their effect on urban air quality, and because of new legislation. In modern heavy-duty applications, the exhaust gases are typically treated with four different catalysts: a Diesel Oxidation Catalyst (DOC) which oxidises HC and CO into H2O and CO2, and NO into NO2, a Diesel Particulate...

  14. Diesel emission reduction using internal exhaust gas recirculation

    Science.gov (United States)

    He, Xin [Denver, CO; Durrett, Russell P [Bloomfield Hills, MI

    2012-01-24

    A method for controlling combustion in a direct-injection diesel engine includes monitoring a crankshaft rotational position of a cylinder of the engine, monitoring an engine load, determining an intake stroke within the cylinder based upon the crankshaft rotational position, and when the engine load is less than a threshold engine load, opening an exhaust valve for the cylinder during a portion of the intake stroke.

  15. Exhaust gas recirculation dispersion analysis using in-cylinder pressure measurements in automotive diesel engines

    OpenAIRE

    Luján, José M.; Climent, H.; Pla Moreno, Benjamín; Rivas Perea, Manuel Eduardo; Francois, Nicolas-Yoan; BORGES ALEJO, JOSE; Soukeur, Zoulikha

    2015-01-01

    Current diesel engines are struggling to achieve exhaust emissions regulations margins, in certain cases penalizing the fuel consumption. The exhaust gas recirculation (EGR) continues to be employed as a technique to reduce NOx emissions. EGR dispersion between cylinders is one important issue when a high pressure (HP) loop is used. Different techniques have been developed in order to analyze the EGR dispersion between cylinders in an engine test bench. In this paper a methodology using the i...

  16. Demonstration of high temperature thermoelectric waste heat recovery from exhaust gases of a combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Trottmann, Matthias; Weidenkaff, Anke; Populoh, Sascha; Brunko, Oliver; Veziridis, Angelika; Bach, Christian; Cabalzar, Urs [Empa, Duebendorf (Switzerland)

    2011-07-01

    The energy efficiency of passenger cars becomes increasingly important due to a growing awareness in terms of climate change and shortages of resources associated with rising fuel prices. In addition to the efforts towards the optimization of the engine's internal efficiency, waste heat recovery is the main objective. In this respect, thermoelectric (TE) devices seem to be suited as heat recuperation systems. Thermoelectric generators allow for direct transformation of thermal into electrical energy. In order to thoroughly investigate this type of recovery system a TE demonstrator was mounted on the muffler of a VW Touran and tested. The waste heat of the exhaust gas was converted into electricity with a conversion rate of {proportional_to}. 3.5%. The limiting factor was the low thermal stability of the commercial modules used in this pre-study to elaborate reference values. Thermoelectric modules based on sustainable and temperature-stable materials are being developed to improve the measured values. A thermoelectric test generator with perovskite-type oxide modules was constructed confirm the function and stability at elevated temperatures. Despite all the advantages of this material class, the TE performance is still to be improved. A quantitative measure of a material's TE performance is the temperature-independent Figure of Merit ZT. ZT increases with decreasing thermal and increasing electrical conductivity. An approach to thermal conductivity reduction is nanostructuring of the material. The Ultrasonic Spray Combustion (USC) technique allows to produce powders with a grain size on the nanoscale and was tested in this study. (orig.)

  17. SUPERCHARGED ENGINE USING TURBINE STANDALONE EXHAUST GAS RECUPERATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Nikola Matulić

    2017-01-01

    Full Text Available This paper presents a new hybrid concept that increases the overall efficiency of the propulsion system on ships. The hybrid concept of the marine propulsion system was examined in 1D CFD internal combustion engine model where the turbine and compressor are not mechanically connected. Such a configuration makes possible different turbine designs than needed in the conventional turbocharger. The advantage is an increased recuperation of energy from exhaust gases. By means of computer simulation and optimization, this study proves that the hybrid concept significantly increases the propulsion system efficiency and lower emissions in maritime environment.

  18. Damage of natural stone tablets exposed to exhaust gas under laboratory conditions

    Science.gov (United States)

    Farkas, Orsolya; Szabados, György; Török, Ákos

    2016-04-01

    Natural stone tablets were exposed to exhaust gas under laboratory conditions to assess urban stone damage. Cylindrical test specimens (3 cm in diameter) were made from travertine, non-porous limestone, porous limestone, rhyolite tuff, sandstone, andesite, granite and marble. The samples were exposed to exhaust gas that was generated from diesel engine combustion (engine type: RÁBA D10 UTSLL 160, EURO II). The operating condition of the internal combustion engine was: 1300 r/m (app 50%). The exhaust gas was diverted into a pipe system where the samples were placed perpendicular to main flow for 1, 2, 4, 8 and 10 hours, respectively. The exhaust emission was measured by using AVL particulate measurement technology; filter paper method (AVL 415). The stone samples were documented and selective parameters were measured prior to and after exhaust gas exposure. Density, volume, ultrasonic pulse velocity, mineral composition and penetration depth of emission related particulate matter were recorded. The first results indicate that after 10 hours of exposure significant amount of particulate matter deposited on the stone surface independently from the surface properties and porosity. The black soot particles uniformly covered all types of stones, making hard to differentiate the specimens.

  19. Modelling for Control of Exhaust Gas Recirculation on Large Diesel Engines

    DEFF Research Database (Denmark)

    Hansen, Jakob Mahler; Zander, Claes-Göran; Pedersen, Nicolai

    2013-01-01

    Exhaust Gas Recirculation (EGR) reduces NOx emissions by reducing O2 concentration for the combustion and is a preferred way to obtain emission regulations that will take effect from 2016. If not properly controlled, reduction of O2 has adverse side eects and proper control requires proper dynamic...... models. While literature is rich on four-stroke automotive engines, this paper considers two-stroke engines and develops a non-linear dynamic model of the exhaust gas system. Parameters are determined by system identication. The paper uses black-box nonlinear model identication and modelling from rst...

  20. A Framework for Modular Modeling of the Diesel Engine Exhaust Gas Cleaning System

    DEFF Research Database (Denmark)

    Åberg, Andreas; Hansen, Thomas Klint; Linde, Kasper

    2015-01-01

    Pollutants from diesel engines have a negative effect on urban air quality. Because of this and new legislation restricting the emission level, it is necessary to develop exhaust gas treatment systems for diesel engines that can reduce the amount of pollutants. A modular model capable of simulating...... model. Four different models in the automotive diesel exhaust gas cleaning system are presented briefly. Based on the presented methodology, it is discussed which changes are needed to the models to create a modular model of the whole catalytic system....

  1. A Preliminary Investigation of Exhaust-Gas Ejectors for Ground Cooling

    Science.gov (United States)

    1942-07-01

    a t insreasing length- diameter rat i o owing t o the di.:nfnieli:ng iniprovement i n energy t ransfer w i t 3 increacinz mixiEg l€iIc-th and...increaee i n horsopcwer results Prom the g rea t e r energy contalned i n the exhaust gas a t the higher powers; whereas, the increase of pressure...of the energy of the exhaust gas t o the cooling sir. drops are insuf f ic ien t f o r s a t i s f ac to ry cooling. a r e obtained f o r the

  2. Redesign of an Exhaust Gas Economiser Using Software

    Science.gov (United States)

    Balaji, R.

    2014-07-01

    Approaches to heat exchanger designs are numerous. Marine heat exchangers are usually single and they do not form part of a large network. Selections are generally based on the duties, area and the heat quantum. Over capacities and un-optimised designs could result. As an exercise to verify the choice, an existing heat exchanger on board of an operational ship was redesigned using computer software with thermodynamic data and standard geometric values. The formulae employed in the software were extracted and verified. The geometric data was used to develop the design drawings using SolidWorks®. Visualising the designs, the physical arrangement was improved. Comparisons and design improvements were made keeping the standard values in view. With the exercises, a method of developing an optimised physical design reducing the number of rating runs has been demonstrated.

  3. Reduction of diesel engine emissions through the recirculation of cooled exhaust gas; Senkung von Diesel-Emissionen durch Rueckfuehrung von gekuehltem Abgas

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, R. [Behr GmbH und Co., Stuttgart (Germany). Entwicklungsteam Abgaswaermeuebertrager

    1997-09-01

    More stringent exhaust regulations for diesel engines which will come into force in Europe (Euro III, 1999) and the USA (2004) will necessitate new methods of reducing emissions, one of which entails the recirculation of cooled exhaust gas. By this process, a certain volume of the exhaust gas is bled off upstream of the turbine, cooled by the engine coolant and remixed with the combustion air down-stream of the intercooler. By contrast with other methods of exhaust gas purification, such as a lean-NO{sub x} catalytic converter, this process needs no second activating agent, such as urea, and, in comparison with a modification of the combustion process, only slightly more fuel. The heat transfer system developed by Behr, which uses the engine coolant to cool the exhaust gas, is capable of withstanding the high temperatures and pressures in the forward section of the exhaust system, is resistant to the sulphuric acid in diesel condensation and, despite its compact design, exhibits a low level of flow resistance. Its exceptional cooling capacity is achieved by a new heat transfer system employing `winglet` turbulence generators. These reduce deposits of soot and other particles on the walls of the heat exchanger to a considerable extent, thereby contributing to its long-term efficiency. (orig.) [Deutsch] Durch die Einfuehrung neuer, strengerer Abgasvorschriften fuer Dieselmotoren 1999 in Europa und 2004 in den USA ruecken neue Techniken zur Emissionssenkung ins Blickfeld. Eine davon ist die gekuehlte Abgasrueckfuehrung, die eine Emissionssenkung bei nur minimalem Anstieg des Kraftstoffverbrauchs erlaubt. An den Waermeuebertrager fuer solch ein System werden hinsichtlich kompakter Bauweise und Leistung, Temperaturbestaendigkeit, Verschutzungs-Unempfindlichkeit und Korrosionsbestaendigkeit hohe Anforderungen gestellt. Der von Behr entwickelte Abgas-Kuehlmittel-Waermeuebertrager erfuellt diese Anforderungen und zeichnet sich durch eine hohe Leistungsdichte aus. Dies

  4. ANALYSIS OF EXHAUST GAS EMISSION IN THE MARINE TWO-STROKE SLOW-SPEED DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    Branko Lalić

    2016-09-01

    Full Text Available This paper explores the problem of exhaust emissions of the marine two-stroke slow-speed diesel engines. After establishing marine diesel engine regulations and defining the parameters influencing exhaust emissions, the simulation model of the marine two-stroke slow-speed diesel engine has been developed. Furthermore, the comparison of numerical and experimentally obtained data has been performed, resulting in achieving the model validity at 100% load, which represents a requirement for further exhaust gas analysis. Deviations obtained at the real engine and the model range from 2% to 7%. An analysis of the influential parameters such as compression ratio, exhaust valve timing and fuel injection timing has been performed. The obtained results have been compared and conclusions have been drawn.

  5. Relationship between the variations of hydrogen in HCNG fuel and the oxygen in exhausted gas

    Directory of Open Access Journals (Sweden)

    Preecha Yaom

    2015-09-01

    Full Text Available The variation of the mixing ratio between hydrogen and compressed natural gas (CNG in hydrogen enriched compressed natural gas fuel (HCNG gives different results in terms of engine performances, fuel consumption, and emission characteristics. Therefore, the engine performance using HCNG as fuel can be optimized if the mixing ratio between the two fuels in HCNG can be adjusted in real time while the engine is being operated. In this research, the relationship between the amount of oxygen in the exhausted gas and the mixing composition between the hydrogen and CNG in HCNG is investigated based on the equilibrium equation of combustion. It is found that the main factors affecting the amount of oxygen in exhausted gas when using HCNG as fuel include the error from the air-fuel-ratio (AFR control, the error from the HCNG composition control, and the intended change of the HCNG composition. Theoretically, the amount of the oxygen in the exhaust should increase by 0.78% for every 5% addition of H2 at stoichiometric condition. This value can be higher or lower for lean and rich engine operation, respectively. The experimental results found that at the equivalent ratio around 0.8 the amount of O2 in the exhaust gas increases about 1.23% for every 5% H2 addition, which inclines with the proposed calculations.

  6. Working fluid selection for the Organic Rankine Cycle (ORC) exhaust heat recovery of an internal combustion engine power plant

    Science.gov (United States)

    Douvartzides, S.; Karmalis, I.

    2016-11-01

    Organic Rankine cycle technology is capable to efficiently convert low-grade heat into useful mechanical power. In the present investigation such a cycle is used for the recovery of heat from the exhaust gases of a four stroke V18 MAN 51/60DF internal combustion engine power plant operating with natural gas. Design is focused on the selection of the appropriate working fluid of the Rankine cycle in terms of thermodynamic, environmental and safety criteria. 37 candidate fluids have been considered and all Rankine cycles examined were subcritical. The thermodynamic analysis of all fluids has been comparatively undertaken and the effect of key operation conditions such as the evaporation pressure and the superheating temperature was taken into account. By appropriately selecting the working fluid and the Rankine cycle operation conditions the overall plant efficiency was improved by 5.52% and fuel consumption was reduced by 12.69%.

  7. Micro- and Nanostructural Characteristics of Particles Before and After an Exhaust Gas Recirculation System Scrubber

    DEFF Research Database (Denmark)

    Lieke, Kirsten Inga; Rosenørn, Thomas; Pedersen, Jannik

    2013-01-01

    This work provides insight into the morphology and mixing state of submicron particles in diesel exhaust from a ship engine with an exhaust gas recirculation scrubber. Particles from this low-speed ship engine on test bed were collected using a microiner-tial impactor with transmission electron...... microscopy (TEM) grids on two stages. Micro- and nanostructural characteristics of sin-gle particles were studied by TEM. Image analysis was carried out on overview and high-resolution images, revealing influence of the exhaust gas treatment (scrubber) on the particle morphology and mixing state. Soot...... agglomerates were found to be collapsed after scrubber, reflected by their change in fractal dimension (fly) from 1.88 to 2.13. Soot was predominantly found internally mixed with other components, with a higher degree of internal mix-ing observed after scrubber. Soot nanostructural characteristics on the near...

  8. Method and system for the purification of exhaust gas with an electrochemical cell

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a method for electrochemical reduction of nitrogen oxides and concomitant oxidation of soot, as well as systems useful therefor. Such methods and systems in particular are useful in the context of exhaust gas purification, in particular for diesel engines....

  9. Carbon dioxide capture and use: organic synthesis using carbon dioxide from exhaust gas.

    Science.gov (United States)

    Kim, Seung Hyo; Kim, Kwang Hee; Hong, Soon Hyeok

    2014-01-13

    A carbon capture and use (CCU) strategy was applied to organic synthesis. Carbon dioxide (CO2) captured directly from exhaust gas was used for organic transformations as efficiently as hyper-pure CO2 gas from a commercial source, even for highly air- and moisture-sensitive reactions. The CO2 capturing aqueous ethanolamine solution could be recycled continuously without any diminished reaction efficiency. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Optimized Design of Thermoelectric Energy Harvesting Systems for Waste Heat Recovery from Exhaust Pipes

    Directory of Open Access Journals (Sweden)

    Marco Nesarajah

    2017-06-01

    Full Text Available With the increasing interest in energy efficiency and resource protection, waste heat recovery processes have gained importance. Thereby, one possibility is the conversion of the heat energy into electrical energy by thermoelectric generators. Here, a thermoelectric energy harvesting system is developed to convert the waste heat from exhaust pipes, which are very often used to transport the heat, e.g., in automobiles, in industrial facilities or in heating systems. That is why a mockup of a heating is built-up, and the developed energy harvesting system is attached. To build-up this system, a model-based development process is used. The setup of the developed energy harvesting system is very flexible to test different variants and an optimized system can be found in order to increase the energy yield for concrete application examples. A corresponding simulation model is also presented, based on previously developed libraries in Modelica®/Dymola®. In the end, it can be shown—with measurement and simulation results—that a thermoelectric energy harvesting system on the exhaust pipe of a heating system delivers extra energy and thus delivers a contribution for a more efficient usage of the inserted primary energy carrier.

  11. Reduced Noise Gas Turbine Engine System and Supersonic Exhaust Nozzle System Using Elector to Entrain Ambient Air

    Science.gov (United States)

    Sokhey, Jagdish S. (Inventor); Pierluissi, Anthony F. (Inventor)

    2017-01-01

    One embodiment of the present invention is a unique gas turbine engine system. Another embodiment is a unique exhaust nozzle system for a gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engine systems and exhaust nozzle systems for gas turbine engines. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  12. Power Output Stability Research for Harvesting Automobile Exhaust Energy with Heat Capacity Material as Intermediate Medium

    Science.gov (United States)

    Xiao, Longjie; He, Tianming; Mei, Binyu; Wang, Yiping; Wang, Zongsong; Tan, Gangfeng

    2018-01-01

    Automobile exhaust energy thermoelectric utilization can promote energy-saving and emission-reduction. Unexpected urban traffic conditions lead to the hot-end temperature instability of the exhaust pipe-mounted thermoelectric generator (TEG), and influence the TEG power generation efficiency. The heat conduction oil circulation located at the hot-end could smooth the temperature fluctuation, at the expense of larger system size and additional energy supply. This research improves the TEG hot-end temperature stability by installing solid heat capacity material (SHCM) to the area between the outer wall of the exhaust pipe and the TEG, which has the merits of simple structure, light weight and no additional energy consumption. The exhaust temperature and flow rate characteristics with various driving conditions are firstly studied for the target engine. Then the convective heat transfer models of SHCM's hot-end and thermoelectric material's cold-end are established. Meanwhile, SHCM thermal properties' effects on the amplitude and response speed of the TEG hot-end temperature are studied. The candidate SHCM with the characteristics of low thermal resistance and high heat capacity is determined. And the heat transfer model going through from TEG's hot-end to the cold-end is established. The results show that the SHCM significantly improves the TEG hot-end temperature stability but slightly reduces the average power output. When the engine working conditions change a lot, the SHCM's improvement on the TEG hot-end temperature stability is more significant, but the reduction of the average power output becomes more remarkable.

  13. Cost Scaling of a Real-World Exhaust Waste Heat Recovery Thermoelectric Generator: A Deeper Dive

    Science.gov (United States)

    Hendricks, Terry J.; Yee, Shannon; LeBlanc, Saniya

    2015-01-01

    Cost is equally important to power density or efficiency for the adoption of waste heat recovery thermoelectric generators (TEG) in many transportation and industrial energy recovery applications. In many cases the system design that minimizes cost (e.g., the $/W value) can be very different than the design that maximizes the system's efficiency or power density, and it is important to understand the relationship between those designs to optimize TEG performance-cost compromises. Expanding on recent cost analysis work and using more detailed system modeling, an enhanced cost scaling analysis of a waste heat recovery thermoelectric generator with more detailed, coupled treatment of the heat exchangers has been performed. In this analysis, the effect of the heat lost to the environment and updated relationships between the hot-side and cold-side conductances that maximize power output are considered. This coupled thermal and thermoelectric treatment of the exhaust waste heat recovery thermoelectric generator yields modified cost scaling and design optimization equations, which are now strongly dependent on the heat leakage fraction, exhaust mass flow rate, and heat exchanger effectiveness. This work shows that heat exchanger costs most often dominate the overall TE system costs, that it is extremely difficult to escape this regime, and in order to achieve TE system costs of $1/W it is necessary to achieve heat exchanger costs of $1/(W/K). Minimum TE system costs per watt generally coincide with maximum power points, but Preferred TE Design Regimes are identified where there is little cost penalty for moving into regions of higher efficiency and slightly lower power outputs. These regimes are closely tied to previously-identified low cost design regimes. This work shows that the optimum fill factor Fopt minimizing system costs decreases as heat losses increase, and increases as exhaust mass flow rate and heat exchanger effectiveness increase. These findings have

  14. Electrocardiographic findings in heat stroke and exhaustion: A study on Makkah pilgrims.

    Science.gov (United States)

    Mimish, L

    2012-01-01

    Over two million pilgrims perform annual rituals in Makkah region, which when coincides with summer months, exposes them to outdoor temperatures exceeding 45 °C and humidity approaching 80%. Accordingly, heat illnesses are common including explicit heat strokes and heat exhaustion. No previous studies elaborated on electrocardiographic changes among this unique cohort. To compare electrocardiographic changes in three groups exposed to high outdoor temperatures, namely, patients with heat stroke compared to patients with heat exhaustion and a control group exposed to the same outdoor temperatures without clinical manifestations. Through case control design, two case groups of patients were selected. The first group (G1) was 34 patients admitted to the cooling units with clinical picture of heat stroke and the second group (G2) comprised 28 patients admitted with heat exhaustion. The control group (G3) included 31 patients selected from relatives of patients and outdoor workers. The outcome for comparison was 12-lead electrocardiographic changes done for all selected individuals. For (G1), the ECG was done while they were prepared for cooling or immediately when cooling was started. In G1, 18 were females and 16 males with ages of 20-76 years (59 ± 11 years). Their heart rates ranged from 64 to 160 beats per minute (mean 120 ± 24 per minute). Only 5/34 ECGs were completely normal. Sinus tachycardia was present in 27/34 patients (79%), with ischemic changes in 9/34 ECGs. In G2, 24 were males and four females with ages of 25-80 (mean 47 ± 15 years), the heart rate ranged from 64 to 170 per minute (mean 97 ± 16 per minute). Seven out of 28 ECGs were normal (25%) while 21/28 had some abnormalities. None had ischemic changes. Control group (G3), was five females and 26 males ages 18-80 years (mean 38 ± 15 years), 22/31 had normal ECGs (71%). All had normal sinus rhythm, 56-98 beats per minute (74 ± 11). Nine patients had some electrocardiographic

  15. Comparison of heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion.

    Science.gov (United States)

    Zhao, Yijie; Yi, Wen; Chan, Albert P C; Chan, Daniel W M

    2017-10-01

    A hot environment combined with physically demanding tasks can subject workers to a higher risk of heat stress. A series of regulations and guidelines have been proposed to design appropriate anti-heat stress work uniform to reduce body heat strain. The present study aimed to examine heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion in the heat. 10 healthy males performed intermittent treadmill running/walking to exhaustion, followed by 30min passive recovery sitting in a climatic chamber, which simulated the hot and humid outdoor environment (34°C temperature, 60% relative humidity, 0.3m/s air velocity, and 450W/m(2) solar radiation). The participants took part in five wear trials in counter-balanced order, including Sportswear, CIC Uniform, NEW Uniform, ICEBANK Cooling Vest, and NEW Cooling Vest, which have different levels of cooling capacity. Core temperature, skin temperature, heart rate, sweat loss, ratings of perceived exertion, and thermal sensations were measured throughout the entire heat exposure period. Physiological heat strain indices, including the physiological strain index (PhSI) and the perceptual strain index (PeSI), were used as a yardstick to quantify and compare the rate of recovery. Significantly lower physiological strain was observed in the newly developed NEW Uniform and NEW Cooling Vest groups compared with the commonly worn CIC Uniform group during recovery. At the end of the recovery period, participants in NEW Cooling Vest achieved the highest recovery (42.18% in PhSI and 81.08% in PeSI), followed by ICEBANK Cooling Vest, Sportswear, NEW Uniform, and CIC Uniform. The cooling capacity of anti-heat stress clothing ensembles and the recovery time significantly affect the rate of recovery in PhSI and PeSI, which may benefit the industry by formulating the appropriate work-rest schedule by considering the clothing effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Heat Transfer Analysis of an Engine Exhaust-Based Thermoelectric Evaporation System

    Science.gov (United States)

    Chen, Ming; Tan, Gangfeng; Guo, Xuexun; Deng, Yadong; Zhang, Hongguang; Yang, Kai

    2016-03-01

    Engine exhaust can be used by thermoelectric generators for improving thermal efficiency of internal combustion engines. In his paper, the performance of a thermoelectric evaporation system is investigated. First, the thermal characteristics of diesel engines are obtained according to the experiment data. Then, mathematical models are created based on the specified conditions of the coolant cycle and the evaporator geometric parameters. Finally, the heat transfer characteristics and power performance of the thermoelectric evaporation system are estimated, and a comparison with the system in which the heat exchanger operates with all-liquid coolant is investigated. The results show that the overall heat transfer rate of the thermoelectric evaporator system increases with engine power. At the rated condition, the two-phase zone with an area of 0.8689 m2 dominates the evaporator's heat transfer area compared with the preheated zone area of 0.0055 m2, and for the thermoelectric module, the cold-side temperature is stable at 74°C while the hot-side temperature drops from 341.8°C to 304.9°C along the exhaust direction. For certain thermoelectric cells, the temperature difference between the cold side and hot side rises with the engine load, and the temperature difference drops from 266.9°C to 230.6°C along the exhaust direction. For two cold-side systems with the same heat transfer, coolant mass flow rate in the evaporator with two-phase state is much less, and the temperature difference along with equivalent heat transfer length L is significantly larger than in the all-liquid one. At rated power point, power generated by thermoelectric cells in the two-phase evaporation system is 508.4 W, while the other is only 328.8 W.

  17. Low-Cost Gas Heat Pump for Building Space Heating

    Energy Technology Data Exchange (ETDEWEB)

    Garrabrant, Michael [Stone Mountain Technologies, Inc., Johnson City, TN (United States); Keinath, Christopher [Stone Mountain Technologies, Inc., Johnson City, TN (United States)

    2016-10-11

    Gas-fired residential space heating in the U.S is predominantly supplied by furnaces and boilers. These technologies have been approaching their thermodynamic limit over the past 30 years and improvements for high efficiency units have approached a point of diminishing return. Electric heat pumps are growing in popularity but their heating performance at low ambient temperatures is poor. The development of a low-cost gas absorption heat pump would offer a significant improvement to current furnaces and boilers, and in heating dominated climate zones when compared to electric heat pumps. Gas absorption heat pumps (GAHP) exceed the traditional limit of thermal efficiency encountered by typical furnaces and boilers, and maintain high levels of performance at low ambient temperatures. The project team designed and demonstrated two low-cost packaged prototype GAHP space heating systems during the course of this investigation. Led by Stone Mountain Technologies Inc. (SMTI), with support from A.O. Smith, and the Gas Technology Institute (GTI), the cross-functional team completed research and development tasks including cycle modeling, 8× scaling of a compact solution pump, combustion system development, breadboard evaluation, fabrication of two packaged prototype units, third party testing of the first prototype, and the evaluation of cost and energy savings compared to high and minimum efficiency gas options. Over the course of the project and with the fabrication of two Alpha prototypes it was shown that this technology met or exceeded most of the stated project targets. At ambient temperatures of 47, 35, 17 and -13°F the prototypes achieved gas based coefficients of performance of 1.50, 1.44, 1.37, and 1.17, respectively. Both units operated with parasitic loads well below the 750 watt target with the second Alpha prototype operating 75-100 watts below the first Alpha prototype. Modulation of the units at 4:1 was achieved with the project goal of 2:1 modulation

  18. Turbine exhaust diffuser with a gas jet producing a coanda effect flow control

    Science.gov (United States)

    Orosa, John; Montgomery, Matthew

    2014-02-11

    An exhaust diffuser system and method for a turbine engine includes an inner boundary and an outer boundary with a flow path defined therebetween. The inner boundary is defined at least in part by a hub structure that has an upstream end and a downstream end. The outer boundary may include a region in which the outer boundary extends radially inward toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. The hub structure includes at least one jet exit located on the hub structure adjacent to the upstream end of the tail cone. The jet exit discharges a flow of gas substantially tangential to an outer surface of the tail cone to produce a Coanda effect and direct a portion of the exhaust flow in the diffuser toward the inner boundary.

  19. Recovery of exhaust waste heat for a hybrid car using steam turbine

    Science.gov (United States)

    Ababatin, Yasser

    A number of car engines operate with an efficiency rate of approximately 22% to 25% [1]. The remainder of the energy these engines generate is wasted through heat escape out of the exhaust pipe. There is now an increasing desire to reuse this heat energy, which would improve the overall efficiency of car engines by reducing their consumption of fuel. Another benefit is that such reuse would minimize harmful greenhouse gases that are emitted into the environment. Therefore, the purpose of this project is to examine how the wasted heat energy can be reused and/or recovered by use of a heat recovery system that would store this energy in a hybrid car battery. Green turbines will be analyzed as a possible solution to recycle the lost energy in a way that will also improve the overall automotive energy efficiency.

  20. A new online exhaust gas monitoring system in hydrochloric acid regeneration of cold rolling mills.

    Science.gov (United States)

    Tuo, Long; Zheng, Xiang; Chen, Xiong

    2017-12-01

    Measuring the content of hydrogen chloride (HCl) in exhaust gas used to take time and energy. In this paper, we introduce a new online monitoring system which can output real-time data to the monitoring center. The system samples and cools exhaust gas, and after a series of processing, it will be analyzed by a specific instrument. The core part of this system is remote terminal unit (RTU) which is designed on Cortex-A8 embedded architecture. RTU runs a scaled-down version of Linux which is a good choice of OS for embedded applications. It controls the whole processes, does data acquisition and data analysis, and communicates with monitoring center through Ethernet. In addition, through a software developed for windows, the monitoring process can be remotely controlled. The new system is quite beneficial for steel industry to do environment monitoring.

  1. 5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-11

    The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22

  2. Energy conservation in fruit dehydrators utilizing recirculation of exhaust air and heat recovery heat exchangers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Groh, J E

    1977-12-01

    Dehydration of fruit in the United States is often done by means of a tunnel dehydrator utilizing large quantities of fossil fuel. Existing dehydrators have been designed to operate with maximum product through-put and with little regard for energy efficiency. Incorporating controlled recirculating air dampers and thermal energy recovery equipment on the exhaust air, calculations and preliminary tests show that the energy required in dehydration may be cut by up to 40%. During this work, one tunnel was modified and upgraded in a commercial 24-tunnel facility to demonstrate the potential savings. A primary element of this program, the heat recovery heat exchanger, operated below specifications. The manufacturer, Hughes Aircraft Company, has determined that the heat exchanger design was based on faulty data, and is constructing a second exchanger which can be installed and tested during a subsequent program.

  3. Energy conservation in fruit dehydrators utilizing recirculation of exhaust air and heat recovery heat exchangers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Groh, J E

    1978-02-01

    Dehydration of fruit in the United States is often done by means of a tunnel dehydrator utilizing large quantities of fossil fuel. Existing dehydrators have been designed to operate with maximum product through-put and with little regard for energy efficiency. Incorporating controlled recirculating air dampers and thermal energy recovery equipment on the exhaust air, calculations and preliminary tests show that the energy required in dehydration may be cut by up to 40 percent. During this work, one tunnel was modified and upgraded in a commercial 24-tunnel facility to demonstrate the potential savings. A primary element of this program, the heat recovery heat exchanger, operated below specifications. The manufacturer, Hughes Aircraft Company, has determined that the heat exchanger design was based on faulty data, and is constructing a second exchanger which can be installed and tested during a subsequent program.

  4. Fiber-optic exhaust-gas sensor based on the fluorescence characteristics of Cu containing zeolites

    Science.gov (United States)

    Remillard, Jeffrey

    2000-03-01

    A single catalyst in the exhaust system can reduce the concentration of toxic gases emitted by automobiles if the engine is operated close to the stoichiometric air-fuel ratio. This is accomplished through the use of an electrochemical oxygen sensor in the exhaust stream. Near the stoichiometric point, this sensor produces a step-function response when the exhaust gas transitions from an oxygen-poor to an oxygen-rich condition. This talk describes a different kind of sensor based on the use of copper-containing zeolites that produces a proportional output. Zeolites are a class of aluminosilicate materials that have an open 3D structure containing channels and cavities. The Al sites are negatively charged and are generally compensated by cations present during formation of the zeolite. Our experiments use a zeolite designated Cu-ZSM-5, which has the protons originally present in the ZSM-5 material replaced with cupric (Cu^+2) ions. Exposure of this zeolite to a reducing gas results in the conversion of some cupric ions to cuprous (Cu^+1) ions. Subsequent exposure of the zeolite to an oxidizing gas reverses this reaction. The use of this material as a gas sensor is based on the observation that cuprous ions produce a green fluorescent emission when exposed to blue light, whereas no fluorescence is observed from cupric ions. Monitoring the fluorescence of Cu-ZSM-5 placed in a gas stream can thus provide information on the gas's reductant-to-oxidant ratio. We present the results of high temperature in-situ fluorescence spectra, intensity, and reponse-time measurements performed on samples of Cu-ZSM-5 exposed to various O_2-reductant combinations and also discuss data obtained from a single-fiber prototype sensor fabricated using a sol-gel processing technique.(J.T. Remillard et al.), Appl. Opt. 38 5306 (1999).

  5. Gas lensing in a heated spinning pipe

    CSIR Research Space (South Africa)

    Mafusire, C

    2006-07-01

    Full Text Available When a heated pipe is rotated, the dynamics of the gas inside exhibit properties reminiscent of a solid-state positive lens. The properties are a result of a parabolic distribution of refractive index in the pipe which is caused by mixing of hot...

  6. Conceptual design study for heat exhaust management in the ARC fusion pilot plant

    Science.gov (United States)

    Dennett, C. A.; Cao, N. M.; Creely, A. J.; Hecla, J.; Hoffman, H.; Kuang, A. Q.; Major, M.; Ruiz Ruiz, J.; Tinguely, R. A.; Tolman, E. A.; Brunner, D.; Labombard, B.; Sorbom, B. N.; Whyte, D. G.; Grover, P.; Laughman, C.

    2017-10-01

    The ARC pilot plant conceptual design study has been extended to explore solutions for managing heat exhaust resulting from 525 MW of fusion power in a compact (R 3.3 m) tokamak. Superconducting poloidal field coils are configured to produce double-null equilibria that support X-point target divertors while maintaining the original core plasma shape and toroidal field coil size. Long outer divertor legs are appended to the original vacuum vessel, providing both large surface areas for surface dissipation of radiative heat and significantly reduced neutron damage for divertor components. A molten salt FLiBe blanket adequately shields all superconductors and functions as a tritium breeder, with advanced neutronics calculations indicating a tritium breeding ratio of 1.08. In addition, FLiBe is used as the active coolant for the entire vessel. A tungsten swirl-tube cooling channel is implemented in the divertor, capable of exhausting 12 MW/m2, heat flux while keeping total FliBe pumping power below 1% of fusion power. Finally, three novel diagnostics are explored: Cherenkov radiation emitted in FLiBe to measure fusion reaction rate, microwave interferometry to measure divertor detachment front location, and IR imaging through the FLiBe blanket to monitor selected divertor ``hotspots.''

  7. Comparative evaluation of three alternative power cycles for waste heat recovery from the exhaust of adiabatic diesel engines

    Science.gov (United States)

    Bailey, M. M.

    1985-01-01

    Three alternative power cycles were compared in application as an exhaust-gas heat-recovery system for use with advanced adiabatic diesel engines. The power cycle alternatives considered were steam Rankine, organic Rankine with RC-1 as the working fluid, and variations of an air Brayton cycle. The comparison was made in terms of fuel economy and economic payback potential for heavy-duty trucks operating in line-haul service. The results indicate that, in terms of engine rated specific fuel consumption, a diesel/alternative-power-cycle engine offers a significant improvement over the turbocompound diesel used as the baseline for comparison. The maximum imporvement resulted from the use of a Rankine cycle heat-recovery system in series with turbocompounding. The air Brayton cycle alternatives studied, which included both simple-cycle and compression-intercooled configurations, were less effective and provided about half the fuel consumption improvement of the Rankine cycle alternatives under the same conditions. Capital and maintenance cost estimates were also developed for each of the heat-recovery power cycle systems. These costs were integrated with the fuel savings to identify the time required for net annual savings to pay back the initial capital investment. The sensitivity of capital payback time to arbitrary increases in fuel price, not accompanied by corresponding hardware cost inflation, was also examined. The results indicate that a fuel price increase is required for the alternative power cycles to pay back capital within an acceptable time period.

  8. ANN based evaluation of the NOx concentration in the exhaust gas of a marine two-stroke diesel engine

    National Research Council Canada - National Science Library

    Kowalski, Jerzy

    2009-01-01

    ...) to the evaluation of NOx concentration in the exhaust gas of a marine two-stroke Diesel engine. A concept is presented how to use the ANN as an alternative to direct measurements carried out on a ship at sea...

  9. A GM (1, 1) Markov Chain-Based Aeroengine Performance Degradation Forecast Approach Using Exhaust Gas Temperature

    OpenAIRE

    Ning-bo Zhao; Jia-long Yang; Shu-ying Li; Yue-wu Sun

    2014-01-01

    Performance degradation forecast technology for quantitatively assessing degradation states of aeroengine using exhaust gas temperature is an important technology in the aeroengine health management. In this paper, a GM (1, 1) Markov chain-based approach is introduced to forecast exhaust gas temperature by taking the advantages of GM (1, 1) model in time series and the advantages of Markov chain model in dealing with highly nonlinear and stochastic data caused by uncertain factors. In this ap...

  10. Multi-Function Gas Fired Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Mehdizadeh Momen, Ayyoub [ORNL; Abu-Heiba, Ahmad [ORNL; Vineyard, Edward Allan [ORNL

    2015-11-01

    The aim of this project was to design a residential fuel fired heat pump and further improve efficiency in collaboration with an industry partner – Southwest Gas, the developer of the Nextaire commercial rooftop fuel-fired heat pump. Work started in late 2010. After extensive search for suitable engines, one manufactured by Marathon was selected. Several prototypes were designed and built over the following four years. Design changes were focused on lowering the cost of components and the cost of manufacturing. The design evolved to a final one that yielded the lowest cost. The final design also incorporates noise and vibration reduction measures that were verified to be effective through a customer survey. ETL certification is currently (as of November 2015) underway. Southwest Gas is currently in talks with GTI to reach an agreement through which GTI will assess the commercial viability and potential of the heat pump. Southwest Gas is searching for investors to manufacture the heat pump and introduce it to the market.

  11. COOLING AND HEATING FUNCTIONS OF PHOTOIONIZED GAS

    Energy Technology Data Exchange (ETDEWEB)

    Gnedin, Nickolay Y. [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Hollon, Nicholas, E-mail: gnedin@fnal.gov [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

    2012-10-15

    Cooling and heating functions of cosmic gas are crucial ingredients for any study of gas dynamics and thermodynamics in the interstellar and intergalactic media. As such, they have been studied extensively in the past under the assumption of collisional ionization equilibrium. However, for a wide range of applications, the local radiation field introduces a non-negligible, often dominant, modification to the cooling and heating functions. In the most general case, these modifications cannot be described in simple terms and would require a detailed calculation with a large set of chemical species using a radiative transfer code (the well-known code Cloudy, for example). We show, however, that for a sufficiently general variation in the spectral shape and intensity of the incident radiation field, the cooling and heating functions can be approximated as depending only on several photoionization rates, which can be thought of as representative samples of the overall radiation field. This dependence is easy to tabulate and implement in cosmological or galactic-scale simulations, thus economically accounting for an important but rarely included factor in the evolution of cosmic gas. We also show a few examples where the radiation environment has a large effect, the most spectacular of which is a quasar that suppresses gas cooling in its host halo without any mechanical or non-radiative thermal feedback.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Yang [Department of Thermal Energy Engineering, Tianjin University, Tianjin 300072 (China)], E-mail: Zhaoyang@tju.edu.cn; Haibo Zhao; Zheng Fang [Department of Thermal Energy Engineering, Tianjin University, Tianjin 300072 (China)

    2007-12-15

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

  13. {open_quotes}Experimental investigation of brown coal combustion with siumlated gas Turbine Exhaust Gas in a combined cycle application

    Energy Technology Data Exchange (ETDEWEB)

    Kakaras, E.; Vourliotis, P.

    1995-12-31

    The main objective of this study is the experimental investigation of the brown coal combustion (brown coal with high sulphur content, e.g. {open_quotes}Megalopolis{close_quotes} lignite) in a lab-scale Atmospheric Fluidized Bed (AFB). The fluidizing gas and the oxidant medium is the Simulated gas Turbine Exhaust flue Gas - {open_quotes}Vitiated Air{close_quotes} (STEG - V.A.). The STEG simulates the exhaust flue gas from the turbine MS 9/1 (FA) produced by EGT - GEC Alsthom (/1/). According to the IFRF experiments, the lowest O{sub 2} level allowed for stable combustion is 10%, concentration which corresponds to 88.4 % burnout in the IFRF experimental furnace. For the improvement of the coal burnout the presence of an oxidation catalyst is considered necessary in order, first, to avoid the incomplete combustion of the coal and second, to decrease the CO and C{sub x}H{sub y} emissions. The catalysts, supplied by KAT-TEC (/4/), are perovskit-type with TiO{sub 2} and Pt as stabilisers. The purposes of the trials are: (1) To examine the possibility to achieve the combustion of low grade brown coal under these conditions. (2) The investigation of the burnout behaviour as well as the resulting O{sub 2} CO{sub 2}, CO, SO{sub 2}, N{sub 2}O, C{sub x}H{sub y} and NO{sub x} emissions.

  14. Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment

    Directory of Open Access Journals (Sweden)

    Ralf Moos

    2010-07-01

    Full Text Available Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more sophisticated approaches based on interactions with electromagnetic waves are also reviewed. For that purpose, metallic stick-like antennas are inserted into the exhaust pipe. The catalyst properties are measured in a contactless manner, directly indicating the catalyst status. The radio frequency probes gauge the oxygen loading degree of three-way catalysts, the NOx-loading of lean NOx traps, and the soot loading of Diesel particulate filters

  15. Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment

    Science.gov (United States)

    Moos, Ralf

    2010-01-01

    Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more sophisticated approaches based on interactions with electromagnetic waves are also reviewed. For that purpose, metallic stick-like antennas are inserted into the exhaust pipe. The catalyst properties are measured in a contactless manner, directly indicating the catalyst status. The radio frequency probes gauge the oxygen loading degree of three-way catalysts, the NOx-loading of lean NOx traps, and the soot loading of Diesel particulate filters. PMID:22163575

  16. Implementation of an experimental pilot reproducing the fouling of the exhaust gas recirculation system in diesel engines

    Directory of Open Access Journals (Sweden)

    Crepeau Gérald

    2012-04-01

    Full Text Available The European emission standards EURO 5 and EURO 6 define more stringent acceptable limits for exhaust emissions of new vehicles. The Exhaust Gas Recirculation (EGR system is a partial but essential solution for lowering the emission of nitrogen oxides and soot particulates. Yet, due to a more intensive use than in the past, the fouling of the EGR system is increased. Ensuring the reliability of the EGR system becomes a main challenge. In partnership with PSA Peugeot Citroën, we designed an experimental setup that mimics an operating EGR system. Its distinctive features are (1 its ability to reproduce precisely the operating conditions and (2 its ability to measure the temperature field on the heat exchanger surface with an Infra Red camera for detecting in real time the evolution of the fooling deposit based on its thermal resistance. Numerical codes are used in conjunction with this experimental setup to determine the evolution of the fouling thickness from its thermal resistance.

  17. New configurations of a heat recovery absorption heat pump integrated with a natural gas boiler for boiler efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Ming [Purdue University, West Lafayette, IN; Abdelaziz, Omar [ORNL; Yin, Hongxi [Southeast University, Nanjing, China

    2014-11-01

    Conventional natural gas-fired boilers exhaust flue gas direct to the atmosphere at 150 200 C, which, at such temperatures, contains large amount of energy and results in relatively low thermal efficiency ranging from 70% to 80%. Although condensing boilers for recovering the heat in the flue gas have been developed over the past 40 years, their present market share is still less than 25%. The major reason for this relatively slow acceptance is the limited improvement in the thermal efficiency of condensing boilers. In the condensing boiler, the temperature of the hot water return at the range of 50 60 C, which is used to cool the flue gas, is very close to the dew point of the water vapor in the flue gas. Therefore, the latent heat, the majority of the waste heat in the flue gas, which is contained in the water vapor, cannot be recovered. This paper presents a new approach to improve boiler thermal efficiency by integrating absorption heat pumps with natural gas boilers for waste heat recovery (HRAHP). Three configurations of HRAHPs are introduced and discussed. The three configurations are modeled in detail to illustrate the significant thermal efficiency improvement they attain. Further, for conceptual proof and validation, an existing hot water-driven absorption chiller is operated as a heat pump at operating conditions similar to one of the devised configurations. An overall system performance and economic analysis are provided for decision-making and as evidence of the potential benefits. These three configurations of HRAHP provide a pathway to achieving realistic high-efficiency natural gas boilers for applications with process fluid return temperatures higher than or close to the dew point of the water vapor in the flue gas.

  18. Variable-geometry turbocharger with asymmetric divided volute for engine exhaust gas pulse optimization

    Science.gov (United States)

    Serres, Nicolas

    2010-11-09

    A turbine assembly for a variable-geometry turbocharger includes a turbine housing defining a divided volute having first and second scrolls, wherein the first scroll has a substantially smaller volume than the second scroll. The first scroll feeds exhaust gas to a first portion of a turbine wheel upstream of the throat of the wheel, while the second scroll feeds gas to a second portion of the wheel at least part of which is downstream of the throat. Flow from the second scroll is regulated by a sliding piston. The first scroll can be optimized for low-flow conditions such that the turbocharger can operate effectively like a small fixed-geometry turbocharger when the piston is closed. The turbine housing defines an inlet that is divided by a dividing wall into two portions respectively feeding gas to the two scrolls, a leading edge of the dividing wall being downstream of the inlet mouth.

  19. Exhaust gas monitoring based on absorption spectroscopy in the process industry

    Science.gov (United States)

    Zhang, Shuai; Liu, Wen-qing; Zhang, Yu-jun; Shu, Xiao-wen; Kan, Rui-feng; Cui, Yi-ben; He, Ying; Xu, Zhen-yu; Geng, Hui; Liu, Jian-guo

    2009-07-01

    This non-invasive gas monitor for exhaust gas monitoring must has high reliability and requires little maintenance. Monitor for in-situ measurements using tunable diode laser absorption spectroscopy (TDLAS) in the near infrared, can meet these requirements. TDLAS has evolved over the past decade from a laboratory especially to an accepted, robust and reliable technology for trace gas sensing. With the features of tunability and narrow linewidth of the distributed feedback (DFB) diode laser and by precisely tuning the laser output wavelength to a single isolated absorption line of the gas, TDLAS technique can be utilized to measure gas concentration with high sensitivity. Typical applications for monitoring of H2S, NH3, HC1 and HF are described here together by wavelength modulation spectroscopy with second-harmonic(WMS-2F) detection. This paper will illustrate the problems related to on-line applications, in particular, the overfall effects, automatic light intensity correction, temperature correction, which impacted on absorption coefficient and give details of how effect of automatic correction is necessary. The system mainly includes optics and electronics, optical system mainly composed of fiber, fiber coupler and beam expander, the electron part has been placed in safe analysis room not together with the optical part. Laser merely passes through one-meter-long pipes by the fiber coupling technology, so the system itself has anti-explosion. The results of the system are also presented in the end, the system's response time is only 0.5s, and can be achieved below 1×10-5 the detection limit at the volume fraction, it can entirely replace the traditional methods of detection exhaust gas in the process industry.

  20. Responses of spruce seedlings (Picea abies) to exhaust gas under laboratory conditions. 1. plant-insect interactions

    Energy Technology Data Exchange (ETDEWEB)

    Viskari, E.-L.; Koessi, S. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Surakka, J.; Pasanen, P.; Ruuskanen, J. [Kuopio Univ. (Finland). Dept. of Environmental Sciences; Mirme, A. [Tartu Univ. (Estonia). Int. of Environmental Physics; Holopainen, J.K. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Agricultural Research Centre, Plant Production research, Jokioinen (Finland)

    2000-07-01

    The effects of motor vehicle exhaust gas on Norway spruce seedlings (Picea abies (L) Karst) and plant-insect interaction of spruce shoot aphid (Cinara pilicornis Hartig) was studied. The exhaust gas concentrations in the fumigation chambers were monitored and controlled by measuring the concentration of nitrogen oxides (NO{sub x}) with a computer aided feedback system. The concentrations of major exhaust gas components (black carbon (BC), fine particles, VOCs and carbonyl compounds) in the chamber air were also measured. Responses of Norway spruce seedlings to a 2 and 3 week exhaust gas exposure and subsequent performance of spruce shoot aphid were studied using realistic exposure regimes; 50, 100 and 200 ppb NO{sub x}. The feedback control system based on NO{sub x} concentrations proved an adequate and practical means for controlling the concentration of exhaust gases and studying plant responses in controlled environment chambers. The exhaust exposure resulted in increased concentrations of proline, glutamine, threonine, aspartic acid, glycine and phenylalanine and decreased concentration of arginine, serine, alanine and glycine in young needles. No changes in soluble N concentrations were observed. The results are interpreted as a stress response rather than use of NO{sub x} as a nitrogen source. No changes in total phenolics and only transient changes in some individual terpene concentrations were detected. The exhaust gas exposure stressed the exposed seedlings, but had no significant effect on N metabolism or the production of defence chemicals. Aphid performance was not significantly affected. Soluble N, secondary metabolism and aphid performance were not sensitive to exhaust gas exposure during shoot elongation in Norway spruce. (author)

  1. Thermoelectric Exhaust Heat Recovery with Heat Pipe-Based Thermal Control

    Science.gov (United States)

    Brito, F. P.; Martins, Jorge; Hançer, Esra; Antunes, Nuno; Gonçalves, L. M.

    2015-06-01

    Heat pipe (HP)-based heat exchangers can be used for very low resistance heat transfer between a hot and a cold source. Their operating temperature depends solely on the boiling point of their working fluid, so it is possible to control the heat transfer temperature if the pressure of the HP can be adjusted. This is the case of the variable conductance HPs (VCHP). This solution makes VCHPs ideal for the passive control of thermoelectric generator (TEG) temperature levels. The present work assesses, both theoretically and experimentally, the merit of the aforementioned approach. A thermal and electrical model of a TEG with VCHP assist is proposed. Experimental results obtained with a proof of concept prototype attached to a small single-cylinder engine are presented and used to validate the model. It was found that the HP heat exchanger indeed enables the TEG to operate at a constant, optimal temperature in a passive and safe way, and with a minimal overall thermal resistance, under part load, it effectively reduces the active module area without deprecating the temperature level of the active modules.

  2. Cooling and Heating Functions of Photoionized Gas

    Energy Technology Data Exchange (ETDEWEB)

    Gnedin, Nickolay Y.; /Chicago U., EFI /Fermilab /Chicago U., Astron. Astrophys. Ctr. /Chicago U., KICP; Hollon, Nicholas; /Chicago U., EFI /Chicago U., Astron. Astrophys. Ctr. /Chicago U., KICP

    2012-01-01

    Cooling functions of cosmic gas are a crucial ingredient for any study of gas dynamics and thermodynamics in the interstellar and intergalactic medium. As such, they have been studied extensively in the past under the assumption of collisional ionization equilibrium. However, for a wide range of applications, the local radiation field introduces a non-negligible, often dominant, modification to the cooling and heating functions. In the most general case, these modifications cannot be described in simple terms, and would require a detailed calculation with a large set of chemical species using a radiative transfer code (the well-known code Cloudy, for example). We show, however, that for a sufficiently general variation in the spectral shape and intensity of the incident radiation field, the cooling and heating functions can be approximated as depending only on (1) the photodissociation rate of molecular hydrogen, (2) the hydrogen photo-ionization rate, and (3) the photo-ionization rate of OVIII;more complex and more accurate approximations also exist. Such dependence is easy to tabulate and implement in cosmological or galactic-scale simulations, thus economically accounting for an important but rarely-included factor in the evolution of cosmic gas. We also show a few examples where the radiation environment has a large effect, the most spectacular of which is a quasar that suppresses gas cooling in its host halo without any mechanical or non-radiative thermal feedback.

  3. Remote gas analysis of aircraft exhausts using FTIR-emission-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Heland, J.; Schaefer, K. [Fraunhofer Inst. for Atmospheric Environmental Research, Garmisch-Partenkirchen (Germany)

    1997-12-31

    FITR emission spectroscopy as a remote sensing multi-component analyzing technique was investigated to determine the composition of aircraft exhausts at ground level. A multi-layer radiative transfer interpretation software based on a line-by-line computer algorithm using the HITRAN data base was developed. Measurements were carried out with different engine types to determine the traceable gas species and their detection limits. Finally validation measurements were made to compare the results of the system to those of conventional equipment. (author) 8 refs.

  4. THIN FILM-BASED SENSOR FOR MOTOR VEHICLE EXHAUST GAS, NH3, AND CO DETECTION

    Directory of Open Access Journals (Sweden)

    S. Sujarwata

    2016-10-01

    Full Text Available A copper phthalocyanine (CuPc thin film based gas sensor with FET structure and channel length 100 μm has been prepared by VE method and lithography technique to detect NH3, motor cycle exhaust gases and CO. CuPc material layer was deposited on SiO2 by the vacuum evaporator (VE method at room temperature and pressure of 8 x10-4 Pa. The stages of manufacturing gas sensor were Si/SiO2 substrate blenching with ethanol in an ultrasonic cleaner, source, and drain electrodes deposition on the substrate by using a vacuum evaporator, thin film deposition between the source/drain and gate deposition. The sensor response times to NH3, motorcycle exhaust gases and CO were 75 s, 135 s, and 150, respectively. The recovery times were 90 s, 150 s and 225, respectively. It is concluded that the CuPc thin film-based gas sensor with FET structure is the best sensor to detect the NH3 gas.Sensor gas berbasis film tipis copper phthalocyanine (CuPc berstruktur FET dengan panjang channel 100 μm telah dibuatdengan metode VE dan teknik lithography untuk mendeteksi NH3 gas buang kendaraan bermotor dan CO. Lapisan bahan CuPc dideposisikan pada permukaan silikon dioksida (SiO2 dengan metode vacuum evaporator (VE pada temperatur ruang dengan tekanan 8 x10-4 Pa. Tahapan pembuatan sensor gas adalah pencucian substrat Si/SiO2 dengan etanol dalam ultrasonic cleaner, deposisi elektroda source dan drain di atas substrat dengan metode vacuum evaporator, deposisi film tipis diantara source/drain dan deposisi gate. Waktu tanggap sensor terhadap NH3, gas buang kendaraan bermotor dan CO berturut-turut adalah 75 s, 135 s,dan 150 s. Waktu pemulihan berturut-turut adalah 90 s, 150 s,dan 225 s. Disimpulkan bahwa sensor gas berstruktur FET berbasis film tipis CuPc merupakan sensor paling baik untuk mendeteksi adanya gas NH3.

  5. Signs and Symptoms of Heat Exhaustion During Strenuous Heat Acclimation Exercise,

    Science.gov (United States)

    1986-10-01

    period in the heat preceeded an antecubital blood sample (days 1 and 8) and body weight (BW) each day (Sauter Co., accuracy ± 10 g). A second antecubital ...a review. Aviat. Space Environ. Med. 47(3):280-301, 1976. 28. Sutton, J.R., and 0. Bar-Or. Thermal illness in fun running. Am. Heart J. 100:778-781

  6. Numerical model of a thermoelectric generator with compact plate-fin heat exchanger for high temperature PEM fuel cell exhaust heat recovery

    DEFF Research Database (Denmark)

    Xin, Gao; Andreasen, Søren Juhl; Chen, Min

    2012-01-01

    This paper presents a numerical model of an exhaust heat recovery system for a high temperature polymer electrolyte membrane fuel cell (HTPEMFC) stack. The system is designed as thermoelectric generators (TEGs) sandwiched in the walls of a compact plate-fin heat exchanger. Its model is based...

  7. Towards long pulse high performance discharges in Tore Supra: experimental knowledge and technological developments for heat exhaust

    Energy Technology Data Exchange (ETDEWEB)

    TORE SUPRA Collaboration

    1995-08-01

    This document deals with fusion heat exhaust experiments in Tore Supra tokamak. The purpose of the Tore Supra tokamak is to achieve and control long pulse powerful discharges. High input power is required to generate the non inductive current, approximately 25 MW . The conception and realisation of a Plasma Facing Component (PFC) scheme able to deal with this large amount of power is the main issue. A description of the water loop used for power removal and of the calorimetric system to determine the overall heat exhaust balance is provided. The infra-red measurements used during plasma operation are also described, together with several heat exhaust devices. The behaviour of ion cyclotron and lower hybrid wave launchers is addressed. Eventually, some information is provided on technological developments of PFC in Tore Supra. (TEC). 61 refs., 34 figs.

  8. Design of a diesel exhaust-gas purification system for inert-gas drilling

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, B.C.

    1982-01-01

    To combat the serious oxygen corrosion of drill pipe when a low density drilling fluid (air or mist) is used in geothermal drilling, a system has been designed that produces an inert gas (essentially nitrogen) to be substituted for air. The system fits on three flatbed trailers, is roadable and produces 2000 scfm of gas. The projected cost for gas is slightly less than $2.00 per thousand standard cubic feet.

  9. Fuel composition and secondary organic aerosol formation: gas-turbine exhaust and alternative aviation fuels.

    Science.gov (United States)

    Miracolo, Marissa A; Drozd, Greg T; Jathar, Shantanu H; Presto, Albert A; Lipsky, Eric M; Corporan, Edwin; Robinson, Allen L

    2012-08-07

    A series of smog chamber experiments were performed to investigate the effects of fuel composition on secondary particulate matter (PM) formation from dilute exhaust from a T63 gas-turbine engine. Tests were performed at idle and cruise loads with the engine fueled on conventional military jet fuel (JP-8), Fischer-Tropsch synthetic jet fuel (FT), and a 50/50 blend of the two fuels. Emissions were sampled into a portable smog chamber and exposed to sunlight or artificial UV light to initiate photo-oxidation. Similar to previous studies, neat FT fuel and a 50/50 FT/JP-8 blend reduced the primary particulate matter emissions compared to neat JP-8. After only one hour of photo-oxidation at typical atmospheric OH levels, the secondary PM production in dilute exhaust exceeded primary PM emissions, except when operating the engine at high load on FT fuel. Therefore, accounting for secondary PM production should be considered when assessing the contribution of gas-turbine engine emissions to ambient PM levels. FT fuel substantially reduced secondary PM formation in dilute exhaust compared to neat JP-8 at both idle and cruise loads. At idle load, the secondary PM formation was reduced by a factor of 20 with the use of neat FT fuel, and a factor of 2 with the use of the blend fuel. At cruise load, the use of FT fuel resulted in no measured formation of secondary PM. In every experiment, the secondary PM was dominated by organics with minor contributions from sulfate when the engine was operated on JP-8 fuel. At both loads, FT fuel produces less secondary organic aerosol than JP-8 because of differences in the composition of the fuels and the resultant emissions. This work indicates that fuel reformulation may be a viable strategy to reduce the contribution of emissions from combustion systems to secondary organic aerosol production and ultimately ambient PM levels.

  10. Exhaust-gas measurements from NASAs HYMETS arc jet.

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Paul Albert

    2010-11-01

    Arc-jet wind tunnels produce conditions simulating high-altitude hypersonic flight such as occurs upon entry of space craft into planetary atmospheres. They have traditionally been used to study flight in Earth's atmosphere, which consists mostly of nitrogen and oxygen. NASA is presently using arc jets to study entry into Mars' atmosphere, which consists of carbon dioxide and nitrogen. In both cases, a wide variety of chemical reactions take place among the gas constituents and with test articles placed in the flow. In support of those studies, we made measurements using a residual gas analyzer (RGA) that sampled the exhaust stream of a NASA arc jet. The experiments were conducted at the HYMETS arc jet (Hypersonic Materials Environmental Test System) located at the NASA Langley Research Center, Hampton, VA. This report describes our RGA measurements, which are intended to be used for model validation in combination with similar measurements on other systems.

  11. Acute acetaminophen (paracetamol) ingestion improves time to exhaustion during exercise in the heat.

    Science.gov (United States)

    Mauger, Alexis R; Taylor, Lee; Harding, Christopher; Wright, Benjamin; Foster, Josh; Castle, Paul C

    2014-01-01

    Acetaminophen (paracetamol) is a commonly used over-the-counter analgesic and antipyretic and has previously been shown to improve exercise performance through a reduction in perceived pain. This study sought to establish whether its antipyretic action may also improve exercise capacity in the heat by moderating the increase in core temperature. On separate days, 11 recreationally active participants completed two experimental time-to-exhaustion trials on a cycle ergometer in hot conditions (30°C, 50% relative humidity) after ingesting a placebo control or an oral dose of acetaminophen in a randomized, double-blind design. Following acetaminophen ingestion, participants cycled for a significantly longer period of time (acetaminophen, 23 ± 15 min versus placebo, 19 ± 13 min; P = 0.005; 95% confidence interval = 90-379 s), and this was accompanied by significantly lower core (-0.15°C), skin (-0.47°C) and body temperatures (0.19°C; P 0.05). This is the first study to demonstrate that an acute dose of acetaminophen can improve cycling capacity in hot conditions, and that this may be due to the observed reduction in core, skin and body temperature and the subjective perception of thermal comfort. These findings suggest that acetaminophen may reduce the thermoregulatory strain elicited from exercise, thus improving time to exhaustion.

  12. Reciprocating Expander for an Exhaust Heat Recovery Rankine Cycle for a Passenger Car Application

    Directory of Open Access Journals (Sweden)

    Osoko Shonda

    2012-06-01

    Full Text Available Nowadays, on average, two thirds of the fuel energy consumed by an engine is wasted through the exhaust gases and the cooling liquid. The recovery of this energy would enable a substantial reduction in fuel consumption. One solution is to integrate a heat recovery system based on a steam Rankine cycle. The key component in such a system is the expander, which has a strong impact on the system’s performance. A survey of different expander technologies leads us to select the reciprocating expander as the most promising one for an automotive application. This paper therefore proposes a steady-state semi-empirical model of the expander device developed under the Engineering Equation Solver (EES environment. The ambient and mechanical losses as well as internal leakage were taken into account by the model. By exploiting the expander manufacturer’s data, all the parameters of the expander model were identified. The model computes the mass flow rate, the power output delivered and the exhaust enthalpy of the steam. The maximum deviation between predictions and measurement data is 4.7%. A performance study of the expander is carried out and shows that the isentropic efficiency is quite high and increases with the expander rotary speed. The mechanical efficiency depends on mechanical losses which are quite high, approximately 90%. The volumetric efficiency was also evaluated.

  13. Vehicle cabin cooling system for capturing and exhausting heated boundary layer air from inner surfaces of solar heated windows

    Science.gov (United States)

    Farrington, Robert B.; Anderson, Ren

    2001-01-01

    The cabin cooling system includes a cooling duct positioned proximate and above upper edges of one or more windows of a vehicle to exhaust hot air as the air is heated by inner surfaces of the windows and forms thin boundary layers of heated air adjacent the heated windows. The cabin cooling system includes at least one fan to draw the hot air into the cooling duct at a flow rate that captures the hot air in the boundary layer without capturing a significant portion of the cooler cabin interior air and to discharge the hot air at a point outside the vehicle cabin, such as the vehicle trunk. In a preferred embodiment, the cooling duct has a cross-sectional area that gradually increases from a distal point to a proximal point to the fan inlet to develop a substantially uniform pressure drop along the length of the cooling duct. Correspondingly, this cross-sectional configuration develops a uniform suction pressure and uniform flow rate at the upper edge of the window to capture the hot air in the boundary layer adjacent each window.

  14. An optical method for measuring exhaust gas pressure from an internal combustion engine at high speed

    Science.gov (United States)

    Leach, Felix C. P.; Davy, Martin H.; Siskin, Dmitrij; Pechstedt, Ralf; Richardson, David

    2017-12-01

    Measurement of exhaust gas pressure at high speed in an engine is important for engine efficiency, computational fluid dynamics analysis, and turbocharger matching. Currently used piezoresistive sensors are bulky, require cooling, and have limited lifetimes. A new sensor system uses an interferometric technique to measure pressure by measuring the size of an optical cavity, which varies with pressure due to movement of a diaphragm. This pressure measurement system has been used in gas turbine engines where the temperatures and pressures have no significant transients but has never been applied to an internal combustion engine before, an environment where both temperature and pressure can change rapidly. This sensor has been compared with a piezoresistive sensor representing the current state-of-the-art at three engine operating points corresponding to both light load and full load. The results show that the new sensor can match the measurements from the piezoresistive sensor except when there are fast temperature swings, so the latter part of the pressure during exhaust blowdown is only tracked with an offset. A modified sensor designed to compensate for these temperature effects is also tested. The new sensor has shown significant potential as a compact, durable sensor, which does not require external cooling.

  15. Compensation of the exhaust gas transport dynamics for accurate instantaneous emission measurements.

    Science.gov (United States)

    Ajtay, Delia; Weilenmann, Martin

    2004-10-01

    Instantaneous emission models of vehicles describe the amount of emitted pollutants as a function of the driving state of the car. Emission measurements of chassis dynamometer tests with high time resolution are necessary for the development of such models. However, the dynamics of gas transport in both the exhaust system of the car and the measurement line last significantly longer than 1 s. In a simplified approach, the transport dynamics can be divided into two parts: a perfect time delay, corresponding to a piston-like transport of the exhaust gas, and a dynamic part, corresponding to the mixing of gases by turbulence along the way. This determines the occurrence of emission peaks that are longer in time and lower in height at the analyzer than they actually are in the vehicle at their location of formation. It is shown here how the sharp emission signals at their location of formation can be reconstructed from the flattened emission signals recorded at the analyzer by using signal theory approaches. A comparison between the reconstructions quality when using the raw or the dilution analyzer system is also given.

  16. HT-PEM Fuel Cell System with Integrated Thermoelectric Exhaust Heat Recovery

    DEFF Research Database (Denmark)

    Gao, Xin

    This thesis presents two case studies on improving the efficiency and the loadfollowing capability of a high temperature polymer electrolyte membrane (HTPEM) fuel cell system by the application of thermoelectric (TE) devices. TE generators (TEGs) are harnessed to recover the system exhaust gas...... power output on the subsystem design and performance were also systematically analyzed. The TEG subsystem configuration is optimized. The usefulness and convenience of the model are proved. TE coolers (TECs) are integrated into the methanol evaporator of the HT-PEM system for improving the whole system...... developed three-dimensional numerical model in ANSYS Fluent®. This thesis introduces the progress of this project in a cognitive order. The first chapter initially prepares the theory and characteristics of the fuel cell system and TE devices. Project motivations are conceived. Then similar studies existing...

  17. Effect of hydroxy (HHO) gas addition on performance and exhaust emissions in compression ignition engines

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Ali Can; Uludamar, Erinc; Aydin, Kadir [Department of Mechanical Engineering, Cukurova University, 01330 Adana (Turkey)

    2010-10-15

    In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH{sub (aq)}, NaOH{sub (aq)}, NaCl{sub (aq)}) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on exhaust emissions and engine performance characteristics were investigated. Experiments showed that constant HHO flow rate at low engine speeds (under the critical speed of 1750 rpm for this experimental study), turned advantages of HHO system into disadvantages for engine torque, carbon monoxide (CO), hydrocarbon (HC) emissions and specific fuel consumption (SFC). Investigations demonstrated that HHO flow rate had to be diminished in relation to engine speed below 1750 rpm due to the long opening time of intake manifolds at low speeds. This caused excessive volume occupation of hydroxy in cylinders which prevented correct air to be taken into the combustion chambers and consequently, decreased volumetric efficiency was inevitable. Decreased volumetric efficiency influenced combustion efficiency which had negative effects on engine torque and exhaust emissions. Therefore, a hydroxy electronic control unit (HECU) was designed and manufactured to decrease HHO flow rate by decreasing voltage and current automatically by programming the data logger to compensate disadvantages of HHO gas on SFC, engine torque and exhaust emissions under engine speed of 1750 rpm. The flow rate of HHO gas was measured by using various amounts of KOH, NaOH, NaCl (catalysts). These catalysts were added into the water to diminish hydrogen and oxygen bonds and NaOH was specified as the most appropriate catalyst. It was observed that if the molality of NaOH in solution exceeded 1% by mass, electrical current supplied from the battery increased dramatically due to the too much

  18. Integrated Heat Exchange For Recuperation In Gas Turbine Engines

    Science.gov (United States)

    2016-12-01

    DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE INTEGRATED HEAT EXCHANGE FOR RECUPERATION IN GAS TURBINE ENGINES 5. FUNDING NUMBERS 6. AUTHOR...ship gas turbines is difficult due the size and weight of the heat exchanger components required. An alternate approach would be to embed a heat ... exchange system within the engine using existing blade surfaces to extract and insert heat . Due to the highly turbulent and transient flow, heat

  19. Motor vehicle exhaust gas suicide in Victoria, Australia 1998-2002.

    Science.gov (United States)

    Brennan, Chris; Routley, Virginia; Ozanne-Smith, Joan

    2006-01-01

    Motor vehicle exhaust gas suicide (MVEGS) is the second most frequent method of suicide in Victoria, Australia. It is a highly lethal method of suicide with 1.5 deaths for every hospital admission. Australian regulations require all vehicles manufactured since 1998 to have a maximum carbon monoxide exhaust emission level of 2.1 g/km, reduced from the previous level of 9.6 g/km. Information surrounding all Victorian MVEGS between 1998-2002 was analyzed to determine whether suicides occurred in vehicles with the lower emission levels. Between 1998-2002, 607 suicides by this means were recorded while just 393 hospital admissions were recorded for the same period. Mean carboxyhaemoglobin levels were significantly lower in fatalities using vehicles manufactured from 1998, however suicide still occurred in these vehicles (n = 25). The extent to which the new regulations contributed to the relatively low rate of suicide in vehicles less than 5 years old compared to their frequency in the fleet remains unknown. Based on international experience and the age of the Victorian vehicle fleet, it may take well over a decade until substantial decreases in MVEGS are observed in the absence of active preventive measures.

  20. Exhaust gas emissions and mutagenic effects of modern diesel fuels, GTL, biodiesel and biodiesel blends

    Energy Technology Data Exchange (ETDEWEB)

    Munack, Axel; Ruschel, Yvonne; Schroeder, Olaf [Federal Research Institute for Rural Areas, Forestry and Fisheries, Braunschweig (Germany)], E-mail: axel.munack@vti.bund.de; Krahl, Juergen [Coburg Univ. of Applied Sciences (Germany); Buenger, Juergen [University of Bochum (Germany)

    2008-07-01

    Biodiesel can be used alone (B100) or blended with petroleum diesel in any proportion. The most popular biodiesel blend in the U.S.A. is B20 (20% biodiesel, 80% diesel fuel), which can be used for Energy Policy Act of 1992 (EPAct) compliance. In the European Union, the use of biofuel blends is recommended and was introduced by federal regulations in several countries. In Germany, biodiesel is currently blended as B5 (5% biodiesel) to common diesel fuel. In 2008, B7 plus three percent hydrotreated vegetable oil (HVO) as well is intended to become mandatory in Germany. To investigate the influence of blends on the emissions and possible health effects, we performed a series of studies with several engines (Euro 0, III and IV) measuring regulated and non-regulated exhaust compounds and determining their mutagenic effects. Emissions of blends showed an approximate linear dependence on the blend composition, in particular when regulated emissions are considered. However, a negative effect of blends was observed with respect to mutagenicity of the exhaust gas emissions. In detail, a maximum of the mutagenic potency was found in the range of B20. From this point of view, B20 must be considered as a critical blend, in case diesel fuel and biodiesel are used as binary mixtures. (author)

  1. A mimic of sexually-motivated homicide: insect stings and heat exhaustion in a forest.

    Science.gov (United States)

    Liu, Nancy X; Pollanen, Michael S

    2017-06-01

    We report the case a woman who was found dead in a forest. The body was nude and the position of the body suggested a sexually motivated homicide. We concluded that death was not related to homicide, but was related to the conjunction of environmental factors, including insect stings, and acute psychosis. A medicolegal death investigation with postmortem examination was undertaken to determine cause of death. At the scene, the body was supine with legs spread apart and the knees flexed, exposing the external genitalia. There were multiple apparent bruises on the body and neck. At autopsy, based on macroscopic and microscopic examination, the apparent bruises were found to be hemorrhagic insect bites. No significant injuries were present and no semen was found. Death appeared to be related to heat exhaustion and innumerable insect stings. Investigation of the medical history revealed longstanding schizoaffective disorder with episodic psychotic decompensations. In the past, during an acute psychotic episode the decedent removed her clothing and ran wildly in a forest, until she was rescued in a state of exhaustion and marked agitation, and taken to hospital for treatment. We concluded that the same circumstances had been repeated but with a fatal outcome. This case is an example of a mimic of sexually-motivated homicide and is a reminder to forensic pathologists to avoid tunnel vision. We need to be skeptical of the allure of common sense based on first impressions of the scene and the body. Forensic pathologists must be unafraid to scientifically explore improbable, but true, alternate explanations.

  2. Research on the Flow Field and Structure Optimization in Cyclone Separator with Downward Exhaust Gas

    Directory of Open Access Journals (Sweden)

    Wang Weiwei

    2017-01-01

    Full Text Available A numerical software analysis of the turbulent and strongly swirling flow field of a cyclone separator with downward exhaust gas and its performances is described. The ANSYS 14.0 simulations based on DPM model are also used in the investigation. A new set of geometrical design has been optimized to achieve minimum pressure drop and maximum separation efficiency. A comparison of numerical simulation of the new design confirm the superior performance of the new design compared to the conventional design. The influence of the structure parameters such as the length of the guide pipe, the shape of the guide, the inlet shape on the separation performance was analyzed in this research. This research result has certain reference value for cyclone separator design and performance optimization.

  3. Study on jet aeration oxidation of magnesium sulfite from magnesium-based exhaust gas cleaning system.

    Science.gov (United States)

    Guo, Lin; Tang, Xiaojia; Wang, Hui; Li, Tie; Liu, Weifeng; Liu, Quan; Zhu, Yimin

    2017-05-11

    Oxidation of magnesium sulfite in washing water is essential for the treatment of by-product of shipboard magnesium-based exhaust gas cleaning systems. The purpose of this study is to obtain a highly efficient magnesium sulfite oxidation technology by using the jet aeration process. Response surface methodology and central composite design were used to investigate the effects of major variables on oxidation of magnesium sulfite and optimize the oxidation conditions. The predictions of the two response functions agree well with the experimental data. The optimum oxidation conditions for ship are temperature 318 K, liquid flow rate 4.04 m3/h, and pH 7.70. Under optimal conditions, 12 moles of magnesium sulfite were oxidized by 90% over 15 minutes at an energy consumption of 0.220 kw h.

  4. Exhaust gas catalysts for heavy-duty vehicles fuelled by alcohol or biogas

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, L.J.; Wahlberg, A.M.; Jaeraas, S.G. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    1997-06-01

    The long-term objective for the project is to develop tailor-made exhaust gas catalysts for heavy-duty ethanol fuelled diesel vehicles operating in urban traffic. Due to special problems, related to emissions of unregulated compounds emanating from ethanol fuelled buses in Swedish fleet tests, a catalyst research programme has been initiated. The engineering target was to achieve a light-off temperature (T{sub 50}) for ethanol conversion below 110 deg C and a selectivity for total oxidation over 90 %. In this report results from laboratory-reactor tests are described. The results indicate that by combining two different precious metals both activity and selectivity can be positively affected compared to the properties of the corresponding mono metallic catalysts. The best results show a light-off temperature for ethanol conversion below 100 deg C. The base metal oxides were more selective for total oxidation than the corresponding precious metal catalysts. The results also indicate a considerable interaction between support and active material which affects the product distribution in catalytic oxidation of ethanol. At temperatures below 250 deg C the by-product formation can be quite high and the major by-product is acetaldehyde. The metal support interaction also has a certain influence on the oxidation of NO to NO{sub 2}. The results show that the NO{sub 2} formation can be suppressed without considerably affecting the activity of the catalyst. This report also includes a preliminary life cycle analysis (LCA) and life cycle cost (LCC) estimate for exhaust gas catalysts intended for heavy-duty ethanol vehicles in urban traffic. 22 refs, numerous figs and tabs

  5. EVALUATION OF DISPERSED PARTICLE CONTENT IN EXHAUST GAS OF DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    G. M. Kuharonak

    2016-01-01

    Full Text Available Pollution of an atmosphere due to hazardous substances emissions deteriorates ecological environment in the world. Exhaust gases of diesel engines are considered as one of the main environmental pollutants. At the moment it is not possible to determine rate and limits of threshold level of air pollution which do not affect human health. The paper considers current issues pertaining to regulation and control over dispersed particles. The most convenient measuring methods for investigations are those which provide the opportunity to obtain immediate results. However, from the legislative point of view, a gravimetric investigation method is a legitimate one which requires compliance with certain procedures of adjustments and calculations. The method presupposes availability of complicated system for sample dilution and its adjustment must include temperature and kinetic parameters of the measured flow. In order to ensure measuring accuracy and results reproducibility filter loading should be in a regulated range and dilution parameters should be chosen according to not only engine type but also according to its emissions rate. Methods for evaluation of a hot exhaust gas sample is characterized by higher response and the results correlate with indices of combustion efficiency. However, such approach does not account for a number of processes that take place during gas cooling in the environment. Therefore, in this case, measuring results are to be evaluated within certain boundary conditions with respect to the object of investigations. Difficulty in achievement of modern ecologocal standards is substantiated by complicated fractional composition and multiple stage process in formation of hazardous components. The paper presents calculated dependences between particles and smokiness and contains a comparative analysis. Methods for measurement and investigations of dispersed particles have analyzed on the basis of the results obtainesd during engine

  6. Gas Generation of Heated PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Matthew David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parker, Gary Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-07

    Uniaxially pressed samples of PBX 9502 were heated until self-ignition (cookoff) in order to collect pressure and temperature data relevant for model development. Samples were sealed inside a small gas-tight vessel, but were mechanically unconfined. Long-duration static pressure rise, as well as dynamic pressure rise during the cookoff event, were recorded. Time-lapse photography of the sample was used to measure the thermal expansion of the sample as a function of time and temperature. High-speed videography qualitatively characterized the mechanical behavior and failure mechanisms at the time of cookoff. These results provide valuable input to modeling efforts, in order to improve the ability to predict pressure output during cookoff as well as the effect of pressure on time-toignition.

  7. Investigation and optimization of the depth of flue gas heat recovery in surface heat exchangers

    Science.gov (United States)

    Bespalov, V. V.; Bespalov, V. I.; Melnikov, D. V.

    2017-09-01

    Economic issues associated with designing deep flue gas heat recovery units for natural gas-fired boilers are examined. The governing parameter affecting the performance and cost of surface-type condensing heat recovery heat exchangers is the heat transfer surface area. When firing natural gas, the heat recovery depth depends on the flue gas temperature at the condenser outlet and determines the amount of condensed water vapor. The effect of the outlet flue gas temperature in a heat recovery heat exchanger on the additionally recovered heat power is studied. A correlation has been derived enabling one to determine the best heat recovery depth (or the final cooling temperature) maximizing the anticipated reduced annual profit of a power enterprise from implementation of energy-saving measures. Results of optimization are presented for a surface-type condensing gas-air plate heat recovery heat exchanger for the climatic conditions and the economic situation in Tomsk. The predictions demonstrate that it is economically feasible to design similar heat recovery heat exchangers for a flue gas outlet temperature of 10°C. In this case, the payback period for the investment in the heat recovery heat exchanger will be 1.5 years. The effect of various factors on the optimal outlet flue gas temperature was analyzed. Most climatic, economical, or technological factors have a minor effect on the best outlet temperature, which remains between 5 and 20°C when varying the affecting factors. The derived correlation enables us to preliminary estimate the outlet (final) flue gas temperature that should be used in designing the heat transfer surface of a heat recovery heat exchanger for a gas-fired boiler as applied to the specific climatic conditions.

  8. Gas turbine heat transfer and cooling technology

    CERN Document Server

    Han, Je-Chin; Ekkad, Srinath

    2012-01-01

    FundamentalsNeed for Turbine Blade CoolingTurbine-Cooling TechnologyTurbine Heat Transfer and Cooling IssuesStructure of the BookReview Articles and Book Chapters on Turbine Cooling and Heat TransferNew Information from 2000 to 2010ReferencesTurbine Heat TransferIntroductionTurbine-Stage Heat TransferCascade Vane Heat-Transfer ExperimentsCascade Blade Heat TransferAirfoil Endwall Heat TransferTurbine Rotor Blade Tip Heat TransferLeading-Edge Region Heat TransferFlat-Surface Heat TransferNew Information from 2000 to 20102.10 ClosureReferencesTurbine Film CoolingIntroductionFilm Cooling on Rotat

  9. Field-effect gas sensors and their application in exhaust treatment systems; Feldeffekt-Gassensoren und ihre Anwendung in Abgasnachbehandlungssystemen

    Energy Technology Data Exchange (ETDEWEB)

    Schalwig, Jan

    2002-07-01

    Tightening environmental constraints on exhaust gas emissions of gasoline and Diesel engines led to a growing interest in new and highly sophisticated gas sensors. Such sensors will be required in future exhaust gas aftertreatment systems for the selective real time detection of pollutants such as nitric oxides, hydrocarbons and carbon monoxide. Restrictions on cost and device dimensions imposed by the automobile industry make semiconductor gas sensors promising candidates for the realization of cheap and small-size sensor devices. This work deals with semiconductor field effect devices with catalytically active platinum (Pt) electrodes and potential applications of such devices in automotive exhaust gas aftertreatment systems. To allow for continuous operation at high temperatures, silicon carbide (SiC) and group III-nitrides such as GaN and AlGaN were used as semiconductor materials. Different devices have been realized with such materials: SiC based MOS capacitors (MOSiC), GaN Schottky diodes and GaN/AlGaN high electron mobility transistors (HEMT). The principle feasibility of SiC and GaN based field effect gas sensors for automotive applications was tested under laboratory conditions using synthetic gas mixtures. Exhaust gas components such as carbon monoxide (CO), nitric oxides (NO and NO{sub 2}), various saturated and unsaturated hydro-carbons as well as water vapor, oxygen (O{sub 2}) and hydrogen (H{sub 2}) were used as test gases in appropriate concentrations with the sensor devices being operated in a range of temperatures extending from room temperature up to 600{sup o}C. (orig.)

  10. Heating and cooling with gas-fired heat-pumps; Heizen und Kuehlen mit Gas-Waermepumpen

    Energy Technology Data Exchange (ETDEWEB)

    Stadelmann, M.

    2008-07-01

    This article takes a look at the use of gas-fired absorption heat-pumps in combined cooling and heating applications. Savings in investments and reduced primary energy consumption along with the resulting lower gas costs are noted. The operation of such 'reversible' systems that use ammonia as a working fluid is briefly described. An installation at a filling station in Taverne, Switzerland, is described. A further installation at a gas utility depot in Givisiez, Switzerland, is also looked at. Here, the gas-powered heat-pump system works together with a solar installation to provide space-heating and cooling as well as hot-water preparation.

  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

    A gas engine-driven heat pump (GHP) uses a natural gas-or LPG-powered engine to drive the compressor in a vapor-compression refrigeration cycle. The GHP has the benefits of being able to use the fuel energy effectively by recovering waste heat from the engine jacket coolant and exhaust gas and also to keep high efficiency even at part-load operation by varying the engine speed with relative ease. Hence, energy-efficient heat source systems for air-conditioning and hot water supply may be constructed with GHP chillers in place of conventional electrical-driven heat pump chillers. GHPs will necessarily contribute to the peak shaving of electrical demand in summer. In this study, the performance characteristics of a 457kW GHP chiller have been investigated by a simulation model analysis, for both cooling and heating modes. From the results of the analysis, it has been found that the part-load characteristics of the GHP chiller are fairly well. The evaluation of the heat source systems using GHP chillers will be described in Part 2.

  12. Dynamic Test Bed Analysis of Gas Energy Balance for a Diesel Exhaust System Fit with a Thermoelectric Generator

    Science.gov (United States)

    Fuc, Pawel; Lijewski, Piotr; Ziolkowski, Andrzej; Dobrzyński, Michal

    2017-05-01

    Analysis of the energy balance for an exhaust system of a diesel engine fit with an automotive thermoelectric generator (ATEG) of our own design has been carried out. A special measurement system and dedicated software were developed to measure the power generated by the modules. The research object was a 1.3-l small diesel engine with power output of 66 kW. The tests were carried out on a dynamic engine test bed that allows reproduction of an actual driving cycle expressed as a function V = f( t), simulating drivetrain (clutch, transmission) operating characteristics, vehicle geometrical parameters, and driver behavior. Measurements of exhaust gas thermodynamic parameters (temperature, pressure, and mass flow) as well as the voltage and current generated by the thermoelectric modules were performed during tests of our own design. Based on the results obtained, the flow of exhaust gas energy in the entire exhaust system was determined along with the ATEG power output. The ideal area of the exhaust system for location of the ATEG was defined to ensure the highest thermal energy recovery efficiency.

  13. Performance analysis of exhaust heat recovery using organic Rankine cycle in a passenger car with a compression ignition engine

    Science.gov (United States)

    Ghilvacs, M.; Prisecaru, T.; Pop, H.; Apostol, V.; Prisecaru, M.; Pop, E.; Popescu, Gh; Ciobanu, C.; Mohanad, A.; Alexandru, A.

    2016-08-01

    Compression ignition engines transform approximately 40% of the fuel energy into power available at the crankshaft, while the rest part of the fuel energy is lost as coolant, exhaust gases and other waste heat. An organic Rankine cycle (ORC) can be used to recover this waste heat. In this paper, the characteristics of a system combining a compression ignition engine with an ORC which recover the waste heat from the exhaust gases are analyzed. The performance map of the diesel engine is measured on an engine test bench and the heat quantities wasted by the exhaust gases are calculated over the engine's entire operating region. Based on this data, the working parameters of ORC are defined, and the performance of a combined engine-ORC system is evaluated across this entire region. The results show that the net power of ORC is 6.304kW at rated power point and a maximum of 10% reduction in brake specific fuel consumption can be achieved.

  14. Exhaust-gas systems for modern furnaces. The most important questions and answers on stacks. 2. rev. and enlarged ed. Abgasanlagen fuer moderne Feuerstaetten. Die wichtigsten Fragen und Antworten rund um den Schornstein

    Energy Technology Data Exchange (ETDEWEB)

    Hoeppner, J.; Postenrieder, E.

    1985-01-01

    The design of the exhaust gas plant for furnaces with chimneys is of great influence on function and economy of gas- and oil furnaces. Information on the most important questions in connection with the chimney is therefore supplied. Contents: chimney engineering, connecting parts (exhaust gas pipes), accessories of exhaust gas equipment, breakdowns and repair, regulations and rules. Terminology and tables are supplied. (BR).

  15. ACCOUNTING FOR NONUNIFORMITY OF WATER CONSUMPTION IN THE EXHAUST AIR HEAT RECLAMATION SYSTEMS FOR HOT WATER SUPPLY

    Directory of Open Access Journals (Sweden)

    Samarin Oleg Dmitrievich

    2017-03-01

    Full Text Available This article is devoted to assessment of the influence of variation of daily hot water consumption on the predicted energy effect by using heat recovery of exhaust air in typical exhaust ventilation systems of the most commonly used flat buildings during their switch to the mechanical induction for the pre-heating of water for hot water supply. It outlines the general principle of the organization of this method of energy saving and presents the basic equations of heat transfer in the heat exchanger. The article proposes a simplified method of accounting for changes in the heat transfer coefficient of air-to-water heat exchanger with fluctuations of water demand using existing dependencies for this coefficient from the rate flow of heating and heated fluid through the device. It presents observations to identify the parameters of the real changes of water consumption during the day with the main quantitative characteristics of normally distributed random variables. Calculation of thermal efficiency of the heat exchange equipment using dimensionless parameters through the number of heat transfer under the optimal opposing scheme of fluid motion is completed under conditions of variable water flow rate for the type residential building of the П3-1/16 series using the Monte Carlo method for numerical modeling of stochastic processes. The estimation of the influence of fluctuation of the current water consumption on the instantaneous thermal efficiency factor of the heat exchanger and the total energy consumption of the building is given, and it is shown that the error of said calculation using average daily parameters is within the margin of usual engineering calculation.

  16. The performance of a new gas to gas heat exchanger with strip fin

    NARCIS (Netherlands)

    Wang, J.; Hirs, Gerard; Rollmann, P.

    1999-01-01

    A compact gas to gas heat exchanger needs large heat transfer areas on both fluid sides. This can be realised by adding secondary surfaces. The secondary surfaces are plate fin, strip fin, and louvered fin, etc. The fins extend the heat transfer surfaces and promote turbulence. This paper presents a

  17. Vehicle exhaust gas clearance by low temperature plasma-driven nano-titanium dioxide film prepared by radiofrequency magnetron sputtering.

    Directory of Open Access Journals (Sweden)

    Shuang Yu

    Full Text Available A novel plasma-driven catalysis (PDC reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2 film prepared by radiofrequency (RF magnetron sputtering was coated on the outer wall of the middle quartz tube, separating the catalyst from the high voltage electrode. The spiral electrodes were designed to avoid overheating of microdischarges inside the PDC reactor. Continuous operation tests indicated that stable performance without deterioration of catalytic activity could last for more than 25 h. To verify the effectiveness of the PDC reactor, a non-thermal plasma(NTP reactor was employed, which has the same structure as the PDC reactor but without the catalyst. The real vehicle exhaust gas was introduced into the PDC reactor and NTP reactor, respectively. After the treatment, compared with the result from NTP, the concentration of HC in the vehicle exhaust gas treated by PDC reactor reduced far more obviously while that of NO decreased only a little. Moreover, this result was explained through optical emission spectrum. The O emission lines can be observed between 870 nm and 960 nm for wavelength in PDC reactor. Together with previous studies, it could be hypothesized that O derived from catalytically O3 destruction by catalyst might make a significant contribution to the much higher HC removal efficiency by PDC reactor. A series of complex chemical reactions caused by the multi-components mixture in real vehicle exhaust reduced NO removal efficiency. A controllable system with a real-time feedback module for the PDC reactor was proposed to further improve the ability of removing real vehicle exhaust gas.

  18. Vehicle Exhaust Gas Clearance by Low Temperature Plasma-Driven Nano-Titanium Dioxide Film Prepared by Radiofrequency Magnetron Sputtering

    Science.gov (United States)

    Yu, Shuang; Liang, Yongdong; Sun, Shujun; Zhang, Kai; Zhang, Jue; Fang, Jing

    2013-01-01

    A novel plasma-driven catalysis (PDC) reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD) reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2) film prepared by radiofrequency (RF) magnetron sputtering was coated on the outer wall of the middle quartz tube, separating the catalyst from the high voltage electrode. The spiral electrodes were designed to avoid overheating of microdischarges inside the PDC reactor. Continuous operation tests indicated that stable performance without deterioration of catalytic activity could last for more than 25 h. To verify the effectiveness of the PDC reactor, a non-thermal plasma(NTP) reactor was employed, which has the same structure as the PDC reactor but without the catalyst. The real vehicle exhaust gas was introduced into the PDC reactor and NTP reactor, respectively. After the treatment, compared with the result from NTP, the concentration of HC in the vehicle exhaust gas treated by PDC reactor reduced far more obviously while that of NO decreased only a little. Moreover, this result was explained through optical emission spectrum. The O emission lines can be observed between 870 nm and 960 nm for wavelength in PDC reactor. Together with previous studies, it could be hypothesized that O derived from catalytically O3 destruction by catalyst might make a significant contribution to the much higher HC removal efficiency by PDC reactor. A series of complex chemical reactions caused by the multi-components mixture in real vehicle exhaust reduced NO removal efficiency. A controllable system with a real-time feedback module for the PDC reactor was proposed to further improve the ability of removing real vehicle exhaust gas. PMID:23560062

  19. Cryogenic flat-panel gas-gap heat switch

    NARCIS (Netherlands)

    Vanapalli, Srinivas; Keijzer, R.; Buitelaar, P.; ter Brake, Hermanus J.M.

    2016-01-01

    A compact additive manufactured flat-panel gas-gap heat switch operating at cryogenic temperature is reported in this paper. A guarded-hot-plate apparatus has been developed to measure the thermal conductance of the heat switch with the heat sink temperature in the range of 100–180 K. The apparatus

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

    Directory of Open Access Journals (Sweden)

    Kuan Wang

    2017-01-01

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

  1. Perancangan Termal Heat Recovery Steam Generator Sistem Tekanan Dua Tingkat Dengan Variasi Beban Gas Turbin

    Directory of Open Access Journals (Sweden)

    Anson Elian

    2017-03-01

    Full Text Available Seiring dengan meningkatnya perkembangan ekonomi suatu negara, maka akan meningkat juga kebutuhan terhadap energi terkhusus pada energi listrik. Salah satu upaya yang dapat dilakukan guna meningkatkan produksi tenaga listrik dengan penggunaan energi bahan bakar fosil seefisien mungkin adalah menggunakan siklus kombinasi PLTGU (Pembangkit Listrik Tenaga Gas dan Uap. Pada sistem PLTGU tersebut terdapat komponen Heat Recovery Steam Generator (HRSG yang bekerja dengan cara menggunakan sisa panas dari gas buang (exhaust gas turbin yang kemudian digunakan untuk memproduksi uap (steam. Studi perancangan termal ini dilakukan dengan menganalisa data input berupa laju alir massa keluaran gas turbin, temperatur keluaran gas turbin, kandungan keluaran gas turbin, temperatur uap keluar HRSG, dan tekanan uap keluar HRSG. Langkah awal adalah menentukan beban kalor pada setiap modul agar dapat menentukan distribusi temperatur pada HRSG. Kemudian masing-masing dari modul HRSG ditentukan luas permukaan perpindahan panas. Lalu, pressure drop dan efisiensi pada sistem HRSG diukur. Terdapat 4 variasi beban turbin gas yaitu saat 100 %, 90%, 80%, dan 70%. Dari variasi tersebut, dapat ditinjau perbedaan laju alir massa uap/air yang dibutuhkan dari masing-masing beban gas turbin. Hasil yang diperoleh dari perancangan ini adalah untuk mengubah air dari 70oC menjadi uap 401oC menggunakan gas buang turbin bertemperatur 437oC, dibutuhkan luas perpindahan panas total sebesar 25.966 m2. Dari analisa variasi beban gas turbin, didapat bahwa semakin tinggi beban gas turbin maka akan semakin tinggi laju alir massa air/uap yang dapat dihasilkan, yaitu pada beban gas turbin 70% didapat 15 kg/s, pada beban gas turbin 80% didapat 15,3 kg/s, pada beban gas turbin 90% didapat 17,37 kg/s, dan pada beban gas turbin 100% didapat 18,59 kg/s.

  2. Unanticipated benefits of automotive emission control: reduction in fatalities by motor vehicle exhaust gas.

    Science.gov (United States)

    Shelef, M

    1994-05-23

    In 1970, before the implementation of strict controls on emissions in motor vehicle exhaust gas (MVEG), the annual USA incidence of fatal accidents by carbon monoxide in the MVEG was approximately 800 and that of suicides approximately 2000 (somewhat less than 10% of total suicides). In 1987, there were approximately 400 fatal accidents and approximately 2700 suicides by MVEG. Accounting for the growth in population and vehicle registration, the yearly lives saved in accidents by MVEG were approximately 1200 in 1987 and avoided suicides approximately 1400. The decrease in accidents continues unabated while the decrease in expected suicides by MVEG reached a plateau in 1981-1983. The reasons for this disparity are discussed. Juxtaposition of these results with the projected cancer risk avoidance of less than 500 annually in 2005 (as compared with 1986) plainly shows that, in terms of mortality, the unanticipated benefits of emission control far overshadow the intended benefits. With the spread of MVEG control these benefits will accrue worldwide.

  3. Histological examination of the rat after long-term exposure to subtoxic automotive exhaust gas.

    Science.gov (United States)

    Roggendorf, W; Neumann, H; Thron, H L; Schneider, H; Sarasa-Corral, J L

    1981-07-01

    Regarding the potential impact of traffic-born air pollutants on public health, in recent years attention has increasingly been focused on the possible effects on the cardiovascular system. In order to investigate this problem further, the influence of long-term exhaust gas exposure on rats has been studied. One hundred Wistar rats of either sex were exposed 5 X 8 h/week up to 28 months to an atmosphere polluted by the emissions of an idling Otto engine, CO concentrations held constant at 90 ppm. A second group (50 rats) was exposed to 250 ppm for 6 months. Blood parameters and body weight were controlled. Specimens of CNS, heart, vessels, kidney etc. were investigated light microscopically. Focal necroses of the myocardium with inflammatory reactions as well as interstitial fibrosis were found in the heart muscle of the 90 ppm group. In the 250 ppm group endothelial proliferations, edema of the intima and deposits of proteoglycanes in the media were observed. We conclude that subtoxic concentrations of CO which only lead to slight morphologic changes may aggravate preexisting lesions caused by high risk conditions, e.g., hypertension or hypercholesteremia.

  4. Establishing isokinetic flow for a plasma torch exhaust gas diagnostic for a plasma hearth furnace

    Energy Technology Data Exchange (ETDEWEB)

    Pollack, Brian R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    1996-05-01

    Real time monitoring of toxic metallic effluents in confined gas streams can be accomplished through use of Microwave Induced Plasmas to perform atomic emission spectroscopy, For this diagnostic to be viable it is necessary that it sample from the flowstream of interest in an isokinetic manner. A method of isokinetic sampling was established for this device for use in the exhaust system of a plasma hearth vitrification furnace. The flow and entrained particulate environment were simulated in the laboratory setting using a variable flow duct of the same dimensions (8-inch diameter, schedule 40) as that in the field and was loaded with similar particulate (less than 10 μm in diameter) of lake bed soil typically used in the vitrification process. The flow from the furnace was assumed to be straight flow. To reproduce this effect a flow straightener was installed in the device. An isokinetic sampling train was designed to include the plasma torch, with microwave power input operating at 2.45 GHz, to match local freestream velocities between 800 and 2400 ft/sec. The isokinetic sampling system worked as planned and the plasma torch had no difficulty operating at the required flowrates. Simulation of the particulate suspension was also successful. Steady particle feeds were maintained over long periods of time and the plasma diagnostic responded as expected.

  5. The Effect of Fuel Dose Division on The Emission of Toxic Components in The Car Diesel Engine Exhaust Gas

    Directory of Open Access Journals (Sweden)

    Pietras Dariusz

    2016-09-01

    Full Text Available The article discusses the effect of fuel dose division in the Diesel engine on smoke opacity and composition of the emitted exhaust gas. The research activities reported in the article include experimental examination of a small Diesel engine with Common Rail type supply system. The tests were performed on the engine test bed equipped with an automatic data acquisition system which recorded all basic operating and control parameters of the engine, and smoke opacity and composition of the exhaust gas. The parameters measured during the engine tests also included the indicated pressure and the acoustic pressure. The tests were performed following the pre-established procedure in which 9 engine operation points were defined for three rotational speeds: 1500, 2500 and 3500 rpm, and three load levels: 25, 40 and 75 Nm. At each point, the measurements were performed for 7 different forms of fuel dose injection, which were: the undivided dose, the dose divided into two or three parts, and three different injection advance angles for the undivided dose and that divided into two parts. The discussion of the obtained results includes graphical presentation of contests of hydrocarbons, carbon oxide, and nitrogen oxides in the exhaust gas, and its smoke opacity. The presented analyses referred to two selected cases, out of nine examined engine operation points. In these cases the fuel dose was divided into three parts and injected at the factory set control parameters. The examination has revealed a significant effect of fuel dose division on the engine efficiency, and on the smoke opacity and composition of the exhaust gas, in particular the content of nitrogen oxides. Within the range of low loads and rotational speeds, dividing the fuel dose into three parts clearly improves the overall engine efficiency and significantly decreases the concentration of nitrogen oxides in the exhaust gas. Moreover, it slightly decreases the contents of hydrocarbons and

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

    DEFF Research Database (Denmark)

    Carlsen, Henrik

    1989-01-01

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

  7. [Research on diagnosis of gas-liquid detonation exhaust based on double optical path absortion spectroscopy technique].

    Science.gov (United States)

    Lü, Xiao-Jing; Li, Ning; Weng, Chun-Sheng

    2014-03-01

    The effect detection of detonation exhaust can provide measurement data for exploring the formation mechanism of detonation, the promotion of detonation efficiency and the reduction of fuel waste. Based on tunable diode laser absorption spectroscopy technique combined with double optical path cross-correlation algorithm, the article raises the diagnosis method to realize the on-line testing of detonation exhaust velocity, temperature and H2O gas concentration. The double optical path testing system is designed and set up for the valveless pulse detonation engine with the diameter of 80 mm. By scanning H2O absorption lines of 1343nm with a high frequency of 50 kHz, the on-line detection of gas-liquid pulse detonation exhaust is realized. The results show that the optical testing system based on tunable diode laser absorption spectroscopy technique can capture the detailed characteristics of pulse detonation exhaust in the transient process of detonation. The duration of single detonation is 85 ms under laboratory conditions, among which supersonic injection time is 5.7 ms and subsonic injection time is 19.3 ms. The valveless pulse detonation engine used can work under frequency of 11 Hz. The velocity of detonation overflowing the detonation tube is 1,172 m x s(-1), the maximum temperature of detonation exhaust near the nozzle is 2 412 K. There is a transitory platform in the velocity curve as well as the temperature curve. H2O gas concentration changes between 0-7% during detonation under experimental conditions. The research can provide measurement data for the detonation process diagnosis and analysis, which is of significance to advance the detonation mechanism research and promote the research of pulse detonation engine control technology.

  8. CO{sub 2}-fertilization via exhaust gas treatment of reciprocating gas engines: developments and experiences; Fertilisation au CO{sub 2} par traitement des gaz provenant de moteurs a gaz alternatifs: developpement et experience

    Energy Technology Data Exchange (ETDEWEB)

    Bekker, M.; Hoving, K.; Klimstra, J.; Top, H. [N.V. Nederlandse Gasunie (Netherlands)

    2000-07-01

    The Dutch climate is such that greenhouses are used to produce vegetables, flowers and other plants. To heat the greenhouse, boilers and combined heat and power systems (CHP) are used. CHP has a better fuel utilisation than a boiler because of the simultaneously production of heat and power. In a greenhouse, CO{sub 2} has to be added to compensate the CO{sub 2} consumed by the plants to grow. Higher CO{sub 2} concentration than ambient are being used to increase plant growth and yield. The use of 'clean' flue gas from boilers was common practice but nowadays flue gas of engines can be used after cleaning. Exhaust gas cleaning systems (EGC) based on a Selective Reduction Catalyst and an Oxidation Catalyst make this possible. This paper describes the principle of these EGCs, gives insight into the important parameters which determine the required cleanliness and discusses the research results of Gasunie Research on this topic. It is found that different catalyst makes have their own specific behaviour depending on the monolith and active material and the how the catalyst is manufactured, mechanical mixed or impregnated. The use of CHP gives a high fuel utilisation and, in combination with EGC, increased crop yields. This results in an even more efficient use of the primary fuel, natural gas. (authors)

  9. Heat transfer across the interface between nanoscale solids and gas.

    Science.gov (United States)

    Cheng, Chun; Fan, Wen; Cao, Jinbo; Ryu, Sang-Gil; Ji, Jie; Grigoropoulos, Costas P; Wu, Junqiao

    2011-12-27

    When solid materials and devices scale down in size, heat transfer from the active region to the gas environment becomes increasingly significant. We show that the heat transfer coefficient across the solid-gas interface behaves very differently when the size of the solid is reduced to the nanoscale, such as that of a single nanowire. Unlike for macroscopic solids, the coefficient is strongly pressure dependent above ∼10 Torr, and at lower pressures it is much higher than predictions of the kinetic gas theory. The heat transfer coefficient was measured between a single, free-standing VO(2) nanowire and surrounding air using laser thermography, where the temperature distribution along the VO(2) nanowire was determined by imaging its domain structure of metal-insulator phase transition. The one-dimensional domain structure along the nanowire results from the balance between heat generation by the focused laser and heat dissipation to the substrate as well as to the surrounding gas, and thus serves as a nanoscale power-meter and thermometer. We quantified the heat loss rate across the nanowire-air interface, and found that it dominates over all other heat dissipation channels for small-diameter nanowires near ambient pressure. As the heat transfer across the solid-gas interface is nearly independent of the chemical identity of the solid, the results reveal a general scaling relationship for gaseous heat dissipation from nanostructures of all solid materials, which is applicable to nanoscale electronic and thermal devices exposed to gaseous environments.

  10. Heat Transfer and Cooling in Gas Turbines

    Science.gov (United States)

    1985-09-01

    the detailed component internal heat transfer for a variety of families of cooling schemes, and (c) to choose from among and withir those families to...1965. 32. Metzger, D.E., and Grochowsky, 1.D., "Heat Transfer Between an Impinging Jet and a Rotating Dink ," J. Heat Tranafer, Trans. ASME, 99, pp. 663

  11. Comparison of primary and secondary particle formation from natural gas engine exhaust and of their volatility characteristics

    Science.gov (United States)

    Alanen, Jenni; Simonen, Pauli; Saarikoski, Sanna; Timonen, Hilkka; Kangasniemi, Oskari; Saukko, Erkka; Hillamo, Risto; Lehtoranta, Kati; Murtonen, Timo; Vesala, Hannu; Keskinen, Jorma; Rönkkö, Topi

    2017-07-01

    Natural gas usage in the traffic and energy production sectors is a growing trend worldwide; thus, an assessment of its effects on air quality, human health and climate is required. Engine exhaust is a source of primary particulate emissions and secondary aerosol precursors, which both contribute to air quality and can cause adverse health effects. Technologies, such as cleaner engines or fuels, that produce less primary and secondary aerosols could potentially significantly decrease atmospheric particle concentrations and their adverse effects. In this study, we used a potential aerosol mass (PAM) chamber to investigate the secondary aerosol formation potential of natural gas engine exhaust. The PAM chamber was used with a constant UV-light voltage, which resulted in relatively long equivalent atmospheric ages of 11 days at most. The studied retro-fitted natural gas engine exhaust was observed to form secondary aerosol. The mass of the total aged particles, i.e., particle mass measured downstream of the PAM chamber, was 6-268 times as high as the mass of the emitted primary exhaust particles. The secondary organic aerosol (SOA) formation potential was measured to be 9-20 mg kgfuel-1. The total aged particles mainly consisted of organic matter, nitrate, sulfate and ammonium, with the fractions depending on exhaust after-treatment and the engine parameters used. Also, the volatility, composition and concentration of the total aged particles were found to depend on the engine operating mode, catalyst temperature and catalyst type. For example, a high catalyst temperature promoted the formation of sulfate particles, whereas a low catalyst temperature promoted nitrate formation. However, in particular, the concentration of nitrate needed a long time to stabilize - more than half an hour - which complicated the conclusions but also indicates the sensitivity of nitrate measurements on experimental parameters such as emission source and system temperatures. Sulfate was

  12. Comparison of primary and secondary particle formation from natural gas engine exhaust and of their volatility characteristics

    Directory of Open Access Journals (Sweden)

    J. Alanen

    2017-07-01

    Full Text Available Natural gas usage in the traffic and energy production sectors is a growing trend worldwide; thus, an assessment of its effects on air quality, human health and climate is required. Engine exhaust is a source of primary particulate emissions and secondary aerosol precursors, which both contribute to air quality and can cause adverse health effects. Technologies, such as cleaner engines or fuels, that produce less primary and secondary aerosols could potentially significantly decrease atmospheric particle concentrations and their adverse effects. In this study, we used a potential aerosol mass (PAM chamber to investigate the secondary aerosol formation potential of natural gas engine exhaust. The PAM chamber was used with a constant UV-light voltage, which resulted in relatively long equivalent atmospheric ages of 11 days at most. The studied retro-fitted natural gas engine exhaust was observed to form secondary aerosol. The mass of the total aged particles, i.e., particle mass measured downstream of the PAM chamber, was 6–268 times as high as the mass of the emitted primary exhaust particles. The secondary organic aerosol (SOA formation potential was measured to be 9–20 mg kgfuel−1. The total aged particles mainly consisted of organic matter, nitrate, sulfate and ammonium, with the fractions depending on exhaust after-treatment and the engine parameters used. Also, the volatility, composition and concentration of the total aged particles were found to depend on the engine operating mode, catalyst temperature and catalyst type. For example, a high catalyst temperature promoted the formation of sulfate particles, whereas a low catalyst temperature promoted nitrate formation. However, in particular, the concentration of nitrate needed a long time to stabilize – more than half an hour – which complicated the conclusions but also indicates the sensitivity of nitrate measurements on experimental parameters such as emission

  13. Gas Turbine Engine with Air/Fuel Heat Exchanger

    Science.gov (United States)

    Karam, Michael Abraham (Inventor); Donovan, Eric Sean (Inventor); Krautheim, Michael Stephen (Inventor); Vetters, Daniel Kent (Inventor); Chouinard, Donald G. (Inventor)

    2017-01-01

    One embodiment of the present invention is a unique aircraft propulsion gas turbine engine. Another embodiment is a unique gas turbine engine. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines with heat exchange systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  14. Emission Characteristics for a Homogeneous Charged Compression Ignition Diesel Engine with Exhaust Gas Recirculation Using Split Injection Methodology

    Directory of Open Access Journals (Sweden)

    Changhee Lee

    2017-12-01

    Full Text Available Due to the serious issues caused by air pollution and global warming, emission regulations are becoming stricter. New technologies that reduce NOx and PM emissions are needed. To cope with these social exhaust gas regulation demands, many advanced countries are striving to develop eco-friendly vehicles in order to respond to stricter emissions regulations. The homogeneous charged compression ignition engine (HCCI incorporates a multi-stage combustion engine with multiple combustion modes, catalyst, direct fuel injection and partial mixing combustion. In this study, the HCCI combustion was applied to analyze and review the results of engines applying HCCI combustion without altering the conventional engine specifications. The optimization of exhaust gas recirculation (EGR and compression ratio changes provides an optimal fuel economy. In this study, potential for optimum economy within the range of IMEP 0.8 MPa has been evaluated.

  15. Simultaneous reduction in cloud point, smoke, and NOx emissions by blending bioethanol into biodiesel fuels and exhaust gas recirculation

    OpenAIRE

    Shudo, T; Nakajima, T.; HIRAGA, K.

    2009-01-01

    Palm oil has the important advantage of productivity compared with other vegetable oils such as rapeseed oil and soybean oil. However, the cold flow performance of palm oil methyl ester (PME) is poorer than other vegetable-oil-based biodiesel fuels. Previous research by the current authors has shown that ethanol blending into PME improves the cold flow performance and considerably reduces smoke emission. The reduced smoke may be expected to allow an expansion in the exhaust gas recirculation ...

  16. Usage of Boiler Unit Exhaust Gas Heat in Contact Heat Exchanger

    Directory of Open Access Journals (Sweden)

    G. I. Zhikhar

    2010-01-01

    Full Text Available The paper presents Results of investigations pertaining to operation of a GM-50-14/250 boiler with a contact economizer are given in the paper. The paper reveals influence of contact economizer on fuel economy and reduction of nitrogen oxide discharge.

  17. Influence of an Optimized Thermoelectric Generator on the Back Pressure of the Subsequent Exhaust Gas System of a Vehicle

    Science.gov (United States)

    Kühn, Roland; Koeppen, Olaf; Kitte, Jens

    2014-06-01

    Numerous research projects in automotive engineering focus on the industrialization of the thermoelectric generator (TEG). The development and the implementation of thermoelectric systems into the vehicle environment are commonly supported by virtual design activities. In this paper a customized simulation architecture is presented that includes almost all vehicle parts which are influenced by the TEG (overall system simulation) but is nevertheless capable of real-time use. Moreover, an optimized planar TEG with minimum nominal power output of about 580 W and pressure loss at nominal conditions of 10 mbar, synthesized using the overall system simulation, and the overall system simulation itself are used to answer a generally neglected question: What influence does the position of a TEG have on the back pressure of the subsequent exhaust gas system of the vehicle? It is found that the influence of the TEG on the muffler is low, but the catalytic converter is strongly influenced. It is shown that the TEG can reduce the back pressure of an exhaust gas system so much that its overall back pressure is less than the back pressure of a standard exhaust gas system.

  18. Technical Analysis Ballast Water Treatment By Using Economizer Utilizing Main Engines Exhaust Heat To Comply With International Ship Ballast Water Management At Mv. Leader Win

    Directory of Open Access Journals (Sweden)

    Hari Prastowo

    2017-03-01

    Full Text Available Based on the International Ballast Water Management regulations (IBWM, waste water ballast itself has the attention of some researchers to reduce the amount of waste species present in the ballast water with a variety of methods, as of biological, physical, mechanical, and chemical. The decision-making tools such as ballast water heater, flow-through system and others where possible these tools can minimize waste species in ballast water at a certain temperature or pressure of the flow according to the calculations. This study was aimed to calculate and analysis the effectiveness of the system treatment between Option 1 (Economizer & Bundle and Option 2 (Economizer & Heat Excharger then it will compare. First option is using economizer and bundles to transfer a heat from a source heat of exhaust gas then medium by thermal oil circulated. The second option is using economizer and heat excharger where a same heat source , but sea water from ballast tank sirculated to heat excharger. And from economizer to heat excharger is using thermal oil as a heat medium. For all calculation and anaalysis is using softwere HTRI. First option having a duty 2.503 MegaWatts at economizer and 1.9567 MegaWatts at bundles. Over design 2.01% at Economizer and 7.1%5 at bundles. Pessure drop 63.287 kPa at thermal oil after economizer and 68.196 kPa after bundles. Treatment time to this option is 44.424 hors. Second option having a duty 3.38 MegaWatts at economizer and 3.1227 MegaWatts at heat excharger. Over design 5.85% at Economizer and 3.49%5 at heat excharger. Pessure drop 38.697 kPa at thermal oil after economizer and 28.476 kPa after heat excharger. Treatment time to second option is 42.03 hours. Option 2 (Economizer & Heat Excharger is more optimum than option in analytical techniques. By analysis of treatment system, are expected this thesis can be applied to either the MV. Leader Win Vessel to comply with the operational needs according to standard

  19. AUTOMATIC CONTROL SYSTEM OF HEAT PUMP STATION GAS COOLER AT THE WIDE RANGE OF HEAT LOAD

    Directory of Open Access Journals (Sweden)

    Juravleov A.A.

    2008-08-01

    Full Text Available There is examined the structure the of control system of gas cooler of heat pump station, which uses the carbon dioxide as the working fluid in the transctitical thermodynamical cycle. It is analiyed the structure of the complex: heat pump station – district heating system.

  20. Energy Factor Analysis for Gas Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Gluesenkamp, Kyle R [ORNL

    2016-01-01

    Gas heat pump water heaters (HPWHs) can improve water heating efficiency with zero GWP and zero ODP working fluids. The energy factor (EF) of a gas HPWH is sensitive to several factors. In this work, expressions are derived for EF of gas HPWHs, as a function of heat pump cycle COP, tank heat losses, burner efficiency, electrical draw, and effectiveness of supplemental heat exchangers. The expressions are used to investigate the sensitivity of EF to each parameter. EF is evaluated on a site energy basis (as used by the US DOE for rating water heater EF), and a primary energy-basis energy factor (PEF) is also defined and included. Typical ranges of values for the six parameters are given. For gas HPWHs, using typical ranges for component performance, EF will be 59 80% of the heat pump cycle thermal COP (for example, a COP of 1.60 may result in an EF of 0.94 1.28). Most of the reduction in COP is due to burner efficiency and tank heat losses. Gas-fired HPWHs are theoretically be capable of an EF of up to 1.7 (PEF of 1.6); while an EF of 1.1 1.3 (PEF of 1.0 1.1) is expected from an early market entry.

  1. Fast temperature programming in gas chromatography using resistive heating

    NARCIS (Netherlands)

    Dallüge, J.; Ou-Aissa, R.; Vreuls, J.J.; Brinkman, U.A.T.; Veraart, J.R.

    1999-01-01

    The features of a resistive-heated capillary column for fast temperature-programmed gas chromatography (GC) have been evaluated. Experiments were carried out using a commercial available EZ Flash GC, an assembly which can be used to upgrade existing gas chromatographs. The capillary column is placed

  2. Minimum gas speed in heat exchangers to avoid particulate fouling

    NARCIS (Netherlands)

    Abd-Elhady, M.S.; Rindt, C.C.M.; Wijers, J.G.; van Steenhoven, A.A.; Bramer, Eduard A.; van der Meer, Theodorus H.

    2004-01-01

    The minimum gas speed for a heat exchanger (HE) at which particulate fouling is avoided is investigated. Fouling experiments have been done with particles of different sizes and different materials running under different gas speeds. It is found that the smallest particles in the flow deposit first

  3. Technoeconomic Optimization of Waste Heat Driven Forward Osmosis for Flue Gas Desulfurization Wastewater Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gingerich, Daniel B [Carnegie Mellon Univ., Pittsburgh, PA (United States); Bartholomew, Timothy V [Carnegie Mellon Univ., Pittsburgh, PA (United States); Mauter, Meagan S [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-06-26

    With the Environmental Protection Agency’s recent Effluent Limitation Guidelines for Steam Electric Generators, power plants are having to install and operate new wastewater technologies. Many plants are evaluating desalination technologies as possible compliance options. However, the desalination technologies under review that can reduce wastewater volume or treat to a zero-liquid discharges standard have a significant energy penalty to the plant. Waste heat, available from the exhaust gas or cooling water from coal-fired power plants, offers an opportunity to drive wastewater treatment using thermal desalination technologies. One such technology is forward osmosis (FO). Forward osmosis utilizes an osmotic pressure gradient to passively pull water from a saline or wastewater stream across a semi-permeable membrane and into a more concentrated draw solution. This diluted draw solution is then fed into a distillation column, where the addition of low temperature waste heat can drive the separation to produce a reconcentrated draw solution and treated water for internal plant reuse. The use of low-temperature waste heat decouples water treatment from electricity production and eliminates the link between reducing water pollution and increasing air emissions from auxiliary electricity generation. In order to evaluate the feasibility of waste heat driven FO, we first build a model of an FO system for flue gas desulfurization (FGD) wastewater treatment at coal-fired power plants. This model includes the FO membrane module, the distillation column for draw solution recovery, and waste heat recovery from the exhaust gas. We then add a costing model to account for capital and operating costs of the forward osmosis system. We use this techno-economic model to optimize waste heat driven FO for the treatment of FGD wastewater. We apply this model to three case studies: the National Energy Technology Laboratory (NETL) 550 MW model coal fired power plant without carbon

  4. HEAT RECOVERY FROM A NATURAL GAS POWERED INTERNAL COMBUSTION ENGINE BY CO2 TRANSCRITICAL POWER CYCLE

    Directory of Open Access Journals (Sweden)

    Mahmood Farzaneh-Gord

    2010-01-01

    Full Text Available The present work provides details of energy accounting of a natural gas powered internal combustion engine and achievable work of a utilized CO2 power cycle. Based on experimental performance analysis of a new designed IKCO (Iran Khodro Company 1.7 litre natural gas powered engine, full energy accounting of the engine were carried out on various engine speeds and loads. Further, various CO2 transcritical power cycle configurations have been appointed to take advantages of exhaust and coolant water heat lost. Based on thermodynamic analysis, the amount of recoverable work obtainable by CO2 transcritical power cycles have been calculated on various engine conditions. The results show that as much as 18 kW power could be generated by the power cycle. This would be considerable amount of power especially if compared with the engine brake power.

  5. Ultra Efficient CHHP Using a High Temperature Fuel Cell to Provide On-Site Process Reducing Gas, Clean Power, and Heat

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, Fred C. [Fuelcell Energy, Inc., Danbury, CT (United States)

    2015-06-30

    FuelCell Energy and ACuPowder investigated and demonstrated the use of waste anode exhaust gas from a high temperature fuel cell for replacing the reducing gas in a metal processing furnace. Currently companies purchase high pressure or liquefied gases for the reducing gas which requires substantial energy in production, compression/liquefaction, and transportation, all of which is eliminated by on-site use of anode exhaust gas as reducing gas. We performed research on the impact of the gas composition on product quality and then demonstrated at FuelCell Energy’s manufacturing facility in Torrington, Connecticut. This demonstration project continues to operate even though the research program is completed as it provides substantial benefits to the manufacturing facility by supplying power, heat, and hydrogen.

  6. Combustion heating value gas in a gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, G. [CTDD, British Coal Corporation, Cheltenham (United Kingdom); Cannon, M. [European Gas Turbines Ltd., Lincoln (United Kingdom)

    1996-12-31

    Advanced coal and/or biomass based power generation systems offer the potential for high efficiency electricity generation with minimum environmental impact. An important component for many of these advanced power generation cycles is the gas turbine, for which development of a combustion system to burn low calorific value coal derived fuel gas, at turbine inlet temperatures of typically 1 100 - 1 260 deg C and with minimum pollutant emissions, is a key issue. A phased combustor development programme is under-way burning low calorific value fuel gas (3.6 - 4.1 MJ/m{sup 3}) with low emissions, particularly NO{sub x} derived from fuel-bound nitrogen. The first and second phases of the combustor development programme have been completed. The first phase used a generic tubo-annular, prototype combustor based on conventional design principles. Combustor performance for this first prototype combustor was encouraging. The second phase assessed five design variants of the prototype combustor, each variant achieving a progressive improvement in combustor performance. The operating conditions for this assessment were selected to represent a particular medium sized industrial gas turbine operating as part of an Air Blown Gasification Cycle (ABGC). The test conditions assessed therefore included the capability to operate the combustor using natural gas as a supplementary fuel, to suit one possible start-up procedure for the cycle. The paper presents a brief overview of the ABGC development initiative and discusses the general requirements for a gas turbine operating within such a cycle. In addition, it presents full combustor performance results for the second phase of turbine combustor development and discusses the rationale for the progressive design modifications made within that programme. The strategy for the further development of the combustor to burn low calorific value fuel gas with very low conversion of fuel-bound nitrogen to NO{sub x} is presented. (orig.) 6 refs.

  7. Simulation for heat flux mitigation by gas puffing in KSTAR

    Science.gov (United States)

    Shim, Seung Bo; Kotov, Vladislav; Hong, Suk-Ho; Detlev, Reiter; Kim, Jin Yong; Na, Yong Su; Lee, Hae June

    2013-10-01

    Control of heat flux is very important to achieve high performance long pulse operation in tokamaks. There are so many efforts to reduce the heat flux like change of divertor structure, snowflake divertor, and RMP, etc. Detachment by gas puffing is used for long time to reduce the heat flux. In this paper edge plasma scenarios of KSTAR are analyzed numerically by well-known B2-Eirene code package(SOLPS4.3). High performance discharges with heating power ~ 8 MW and core flux ~ 1021 s-1 is used. Gas puffed on the outer mid-plane(OMP), both divertors is likely to stay attached. So, gas puffed on the outer target, one is near the private flux region(PFR) and the other is near the scrape-off-layer(SOL). When gas puffed near the SOL is still attached, and it is worse than gas puff from OMP because it is too close to cryo-pump. The case near the PFR shows high recycling region easily compared with OMP case. When one forth gas puffed on the PFR, results are similar with OMP case. But it is still not good for detachment operation. Detachment operation window is too small for the gas puffing on the PFR. This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST)(No. 2012-0000579).

  8. Experimental study on Rankine cycle evaporator efficiency intended for exhaust waste heat recovery of a diesel engine

    Directory of Open Access Journals (Sweden)

    Milkov Nikolay

    2017-01-01

    Full Text Available The paper pressents an experimental study of Rankine cycle evaporator efficiency. Water was chosen as the working fluid in the system. The experimental test was conducted on a test bench equipped with a burner charged by compressed fresh air. Generated exhaust gases parameters were previously determined over the diesel engine operating range (28 engine operating points were studied. For each test point the working fluid parameters (flow rate and evaporating pressure were varied. Thus, the enthalpy flow through the heat exchanger was determined. Heat exchanger was designed as 23 helical tubes are inserted. On the basis of the results, it was found out that efficiency varies from 25 % to 51,9 %. The optimal working fluid pressure is 20 bar at most of the operating points while the optimum fluid mass flow rate varies from 2 g/s to 10 g/s.

  9. Heat Recovery from Ketene Gas Cooldown.

    Science.gov (United States)

    1984-06-01

    problems using full combustion air preheat for a third mouth when data collection for the ketene cooldown project was terminated . Efforts to obtain...production (100/ basis) were higher during the months when the heat exchanger proceo ;a; was being used. While the 24-hour averages for anhydride concentration

  10. Fast spatially resolved exhaust gas recirculation (EGR) distribution measurements in an internal combustion engine using absorption spectroscopy.

    Science.gov (United States)

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

    2015-09-01

    Exhaust gas recirculation (EGR) in internal combustion engines is an effective method of reducing NOx emissions while improving efficiency. However, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder non-uniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. A sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. The study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.

  11. Influence of gas emission on heat transfer in porous ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Gambaryan-Roisman, T.; Shapiro, M.; Litovsky, E.; Shavit, A. [Laboratory of Transport Processes in Porous Materials, Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa 32000 (Israel)

    2003-01-01

    It is known that thermal diffusivity, a, of several types of porous ceramic and refractory materials decreases with decreasing gas pressure. However, a of several ceramics (e.g., magnesite refractories with porosity about 25%) measured in vacuum by the monotonous heating exceeds the comparable data registered at atmospheric pressure. A similar effect was found for thermal diffusivity of several insulating materials. However, for some porous ceramics this phenomenon is absent or less prominent. It had been known that several heterogeneous physico-chemical processes take place on pore surfaces of ceramic materials. These processes include heterogeneous chemical reactions accompanied by emission of gaseous products. It had been conjectured that these processes affect thermophysical properties of ceramic materials, especially during fast heating or cooling. In this paper we substantiate this conjecture. Namely, we develop a quantitative model for the apparent thermal diffusivity, as measured by the nonstationary monotonous heating method. It takes into account the emission and adsorption of the gas on the opposite pore sides along the temperature gradient, the diffusive gas motion inside the pores and its removal from the pores due to the material gas permeability. The effect of these processes is shown to produce an additional heat flux inside the pore or crack and, hence, to increase the measured thermal diffusivity. In the presence of the passive gas, the rates of gas emission and its transport within the pore are significantly reduced, which leads to diminution of the effect of gas emission-adsorption on the heat transfer across the pore. Consequently, we show that this leads to a situation (observed in experiment) where thermal diffusivity of a material measured at high temperature in vacuum may exceed the comparable property at atmospheric pressure. When the reaction terminates due to the full conversion of the available solid reactant, the additional heat flow

  12. Calculation of heating systems for houses. [Gas heating]. Beregning af varmeanlaeg til parcelhuse

    Energy Technology Data Exchange (ETDEWEB)

    Savstrup Kristensen, L.

    1994-02-01

    Guidelines for calculations and dimensioning related to gas-fired heating systems for detached or terrace houses. Determination of heat losses, the size of boilers, hot water containers and radiators, pipe systems and the calculations of pressure loss are dealt with. (AB)

  13. Startup analysis for a high temperature gas loaded heat pipe

    Science.gov (United States)

    Sockol, P. M.

    1973-01-01

    A model for the rapid startup of a high-temperature gas-loaded heat pipe is presented. A two-dimensional diffusion analysis is used to determine the rate of energy transport by the vapor between the hot and cold zones of the pipe. The vapor transport rate is then incorporated in a simple thermal model of the startup of a radiation-cooled heat pipe. Numerical results for an argon-lithium system show that radial diffusion to the cold wall can produce large vapor flow rates during a rapid startup. The results also show that startup is not initiated until the vapor pressure p sub v in the hot zone reaches a precise value proportional to the initial gas pressure p sub i. Through proper choice of p sub i, startup can be delayed until p sub v is large enough to support a heat-transfer rate sufficient to overcome a thermal load on the heat pipe.

  14. Performance of Gas-Engine Driven Heat Pump Unit

    Energy Technology Data Exchange (ETDEWEB)

    Abdi Zaltash; Randy Linkous; Randall Wetherington; Patrick Geoghegan; Ed Vineyard; Isaac Mahderekal; Robert Gaylord

    2008-09-30

    Air-conditioning (cooling) for buildings is the single largest use of electricity in the United States (U.S.). This drives summer peak electric demand in much of the U.S. Improved air-conditioning technology thus has the greatest potential impact on the electric grid compared to other technologies that use electricity. Thermally-activated technologies (TAT), such as natural gas engine-driven heat pumps (GHP), can provide overall peak load reduction and electric grid relief for summer peak demand. GHP offers an attractive opportunity for commercial building owners to reduce electric demand charges and operating expenses. Engine-driven systems have several potential advantages over conventional single-speed or single-capacity electric motor-driven units. Among them are variable speed operation, high part load efficiency, high temperature waste heat recovery from the engine, and reduced annual operating costs (SCGC 1998). Although gas engine-driven systems have been in use since the 1960s, current research is resulting in better performance, lower maintenance requirements, and longer operating lifetimes. Gas engine-driven systems are typically more expensive to purchase than comparable electric motor-driven systems, but they typically cost less to operate, especially for commercial building applications. Operating cost savings for commercial applications are primarily driven by electric demand charges. GHP operating costs are dominated by fuel costs, but also include maintenance costs. The reliability of gas cooling equipment has improved in the last few years and maintenance requirements have decreased (SCGC 1998, Yahagi et al. 2006). Another advantage of the GHP over electric motor-driven is the ability to use the heat rejected from the engine during heating operation. The recovered heat can be used to supplement the vapor compression cycle during heating or to supply other process loads, such as water heating. The use of the engine waste heat results in greater

  15. Performance improvement of optical fiber coupler with electric heating versus gas heating.

    Science.gov (United States)

    Shuai, Cijun; Gao, Chengde; Nie, Yi; Peng, Shuping

    2010-08-20

    Gas heating has been widely used in the process of fused biconical tapering. However, as the instability and asymmetric flame temperature of gas heating exist, the performance of the optical devices fabricated by this method was affected. To overcome the problems resulting from gas combustion, an electric heater is designed and manufactured using a metal-ceramic (MoSi(2)) as a heating material. Our experimental data show that the fused-taper machine with an electric heater has improved the performance of optical devices by increasing the consistency of the extinction ratio, excess loss, and the splitting ratio over that of the previous gas heating mode. Microcrystallizations and microcracks were observed at the fused region of the polarization-maintaining (PM) fiber coupler and at the taper region with scanning electron microscopy and atomic force microscopy respectively. The distribution of the microcrystallizations and microcracks are nonuniform along the fiber with gas heating, while their distribution is rather uniform with electric heating. These findings show that the novel optical fiber coupler with an electric heater has improved the performance of optical fiber devices by affecting the consistency of the optical parameters and micromorphology of the surface of PM fiber.

  16. A Fault Diagnosis Approach for Gas Turbine Exhaust Gas Temperature Based on Fuzzy C-Means Clustering and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Zhi-tao Wang

    2015-01-01

    Full Text Available As an important gas path performance parameter of gas turbine, exhaust gas temperature (EGT can represent the thermal health condition of gas turbine. In order to monitor and diagnose the EGT effectively, a fusion approach based on fuzzy C-means (FCM clustering algorithm and support vector machine (SVM classification model is proposed in this paper. Considering the distribution characteristics of gas turbine EGT, FCM clustering algorithm is used to realize clustering analysis and obtain the state pattern, on the basis of which the preclassification of EGT is completed. Then, SVM multiclassification model is designed to carry out the state pattern recognition and fault diagnosis. As an example, the historical monitoring data of EGT from an industrial gas turbine is analyzed and used to verify the performance of the fusion fault diagnosis approach presented in this paper. The results show that this approach can make full use of the unsupervised feature extraction ability of FCM clustering algorithm and the sample classification generalization properties of SVM multiclassification model, which offers an effective way to realize the online condition recognition and fault diagnosis of gas turbine EGT.

  17. Gas purge-microsyringe extraction: a rapid and exhaustive direct microextraction technique of polycyclic aromatic hydrocarbons from plants.

    Science.gov (United States)

    Wang, Juan; Yang, Cui; Li, Huijie; Piao, Xiangfan; Li, Donghao

    2013-12-17

    Gas purge-microsyringe extraction (GP-MSE) is a rapid and exhaustive microextraction technique for volatile and semivolatile compounds. In this study, a theoretical system of GP-MSE was established by directly extracting and analyzing 16 kinds of polycyclic aromatic hydrocarbons (PAHs) from plant samples. On the basis of theoretical consideration, a full factorial experimental design was first used to evaluate the main effects and interactions of the experimental parameters affecting the extraction efficiency. Further experiments were carried out to determine the extraction kinetics and desorption temperature-dependent. The results indicated that three factors, namely desorption temperature (temperature of sample phase) Td, extraction time t, and gas flow rate u, had a significantly positive effect on the extraction efficiency of GP-MSE for PAHs. Extraction processes of PAHs in plant samples followed by first-order kinetics (relative coefficient R(2) of simulation curves were 0.731-1.000, with an average of 0.958 and 4.06% relative standard deviation), and obviously depended on the desorption temperature. Furthermore, the effect of the matrix was determined from the difference in Eapp,d. Finally, satisfactory recoveries of 16 PAHs were obtained using optimal parameters. The study demonstrated that GP-MSE could provide a rapid and exhaustive means of direct extraction of PAHs from plant samples. The extraction kinetics were similar that of the inverse process of the desorption kinetics of the sample phase. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Tuning the structure of platinum particles on ceria in situ for enhancing the catalytic performance of exhaust gas catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gaenzler, Andreas M.; Casapu, Maria; Grunwaldt, Jan-Dierk [Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Vernoux, Philippe; Loridant, Stephane; Cadete Santos Aires, Francisco J. [Institut de Recherches sur la Catalyse et l' Environnement de Lyon, UMR 5256, CNRS, Universite Claude Bernard Lyon 1, Universite de Lyon, Villeurbanne (France); Epicier, Thierry [Materiaux, Ingenierie et Science, UMR 5510, CNRS, INSA de Lyon, Universite de Lyon, Villeurbanne (France); Betz, Benjamin [Umicore AG and Co. KG, Hanau (Germany); Ernst-Berl Institut, Technische Universitaet Darmstadt (Germany); Hoyer, Ruediger [Umicore AG and Co. KG, Hanau (Germany)

    2017-10-09

    A dynamic structural behavior of Pt nanoparticles on the ceria surface under reducing/oxidizing conditions was found at moderate temperatures (<500 C) and exploited to enhance the catalytic activity of Pt/CeO{sub 2}-based exhaust gas catalysts. Redispersion of platinum in an oxidizing atmosphere already occurred at 400 C. A protocol with reducing pulses at 250-400 C was applied in a subsequent step for controlled Pt-particle formation. Operando X-ray absorption spectroscopy unraveled the different extent of reduction and sintering of Pt particles: The choice of the reductant allowed the tuning of the reduction degree/particle size and thus the catalytic activity (CO>H{sub 2}>C{sub 3}H{sub 6}). This dynamic nature of Pt on ceria at such low temperatures (250-500 C) was additionally confirmed by in situ environmental transmission electron microscopy. A general concept is proposed to adjust the noble metal dispersion (size, structure), for example, during operation of an exhaust gas catalyst. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Vehicle Exhaust Waste Heat Recovery Model with Integrated Thermal Load Leveling

    Science.gov (United States)

    2015-08-01

    advantages that make them particularly attractive for mobile applications including being lightweight , solid- state, and passive. This has the potential for...recovery from automobile engine. Energy. 2010;35:1447–1454. 14 12. Ceraianu MO, Gontean A. Parasitic elements modelling in thermoelectric...JP, Sampath S. Heat transfer modeling and geometry optimization of TEG for automobile applications. Proceedings of the ASME Summer Heat Transfer

  20. Conceptual study of ferromagnetic pebbles for heat exhaust in fusion reactors with short power decay length

    Directory of Open Access Journals (Sweden)

    N. Gierse

    2015-03-01

    The key results of this study are that very high heat fluxes are accessible in the operation space of ferromagnetic pebbles, that ferromagnetic pebbles are compatible with tokamak operation and current divertor designs, that the heat removal capability of ferromagnetic pebbles increases as λq decreases and, finally, that for fusion relevant values of q∥ pebble diameters below 100 μm are required.

  1. Emission characteristics of iso-propanol/gasoline blends in a spark-ignition engine combined with exhaust gas re-circulation

    Directory of Open Access Journals (Sweden)

    Gong Jing

    2014-01-01

    Full Text Available Experiments were carried out in a spark-ignition engine fueled with iso-propanol/gasoline blends. Emission characteristics of this engine were investigated experimentally, including gaseous emissions (HC, CO, NOx and particulate matter emission in term of number and size distributions. The effects of different iso-propanol percentages, loads and exhaust gas recirculation rates on emissions were analyzed. Results show that the introduction of exhaust gas recirculation reduces the NOx emission and NOx emission gives the highest value at full load condition. HC and CO emissions present inconspicuous variations at all the loads except the load of 10%. Additionally, HC emission shows a sharp increase for pure propanol when the exhaust gas recirculation rate is up to 5%, while little variation is observed at lager exhaust gas recirculation rates. Moreover, the particulate matter number concentration increases monotonically with the increase of load and the decrease of exhaust gas recirculation rate. There exists a critical spark timing that produces the highest particulate matter number concentration at all the blending ratios.

  2. Stagnation Point Heat Transfer with Gas Injection Cooling

    Science.gov (United States)

    Vancrayenest, B.; Tran, M. D.; Fletcher, D. G.

    2005-01-01

    The present paper deals with an experimental study of the stagnation-point heat transfer to a cooled copper surface with gas injection under subsonic conditions. Test were made with a probe that combined a steady-state water-cooled calorimeter that allows the capability to study convective blockage and to perform heat transfer measurements in presence of gas injection in the stagnation region. The copper probe was pierced by 52 holes, representing 2.4% of the total probe surface. The 1.2 MW high enthalpy plasma wind tunnel was operated at anode powers between 130 and 230 kW and a static pressures from 35 hPa up to 200 hPa. Air, carbon dioxide and argon were injected in the mass flow range 0-0.4 g/s in the boundary layer developed around the 50 mm diameter probe. The measured stagnation-point heat transfer rates are reported and discussed.

  3. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... for signs of heat stroke or exhaustion. Heat Stroke and Exhaustion Symptoms of early heat exhaustion symptoms ... heavy sweating; nausea; and giddiness. Symptoms of heat stroke (late stage of heat illness) include flushed, hot, ...

  4. Exhaustion of the gas next to the supermassive black hole of M31

    Science.gov (United States)

    Melchior, Anne-Laure; Combes, Françoise

    2017-11-01

    New observations performed at the IRAM Plateau de Bure reveal the absence of molecular gas next to the black hole of the Andromeda galaxy. We derived a 3σ upper limit on the molecular gas mass of 4300 M⊙ for a line width of 1000 km s-1. This is compatible with infra-red observations, which reveal a hole in the dust emission next to the black hole. Some gas from stellar feedback is expected from the old eccentric stellar disc population, but it is not accreted close to the black hole. This absence of gas explains the absence of stellar formation observed in this region, contrary to what is observed next to Sgr A* in the Milky Way. Either the gas has been swallowed by the black hole, or a feedback mechanism has pushed the gas outside the central 1 pc. Nevertheless, we detect a small clump of gas with a very low velocity dispersion at 2.4″ from the black hole. It is probable that this clumpy gas is seen in projection, as it does not follow the rotation of the disc surrounding the black hole, its velocity dispersion is ten times lower than the expected velocity gradient, and the tidal shear from the black hole requires a gas density for this clump that is not compatible with our observations.

  5. Dynamic Allocation of a Domestic Heating Task to Gas-Based and Heatpump-Based Heating Agents

    NARCIS (Netherlands)

    Treur, J.

    2013-01-01

    In this paper a multi-agent model for a domestic heating task is introduced and analysed. The model includes two alternative heating agents (for gas-based heating and for heatpump-based heating), and a third allocation agent which determines the most economic allocation of the heating task to these

  6. Gas Engine-Driven Heat Pump with Desiccant Dehumidification

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo [ORNL; Abu-Heiba, Ahmad [ORNL

    2017-01-01

    About 40% of total U.S. energy consumption was consumed in residential and commercial buildings. Improved air-conditioning technology has by far the greatest potential impact on the electric industry compared to any other technology that uses electricity. This paper describes the development of an innovative natural gas, propane, LNG or bio-gas IC engine-driven heat pump (GHP) with desiccant dehumidification (GHP/DD). This integrated system has higher overall efficiencies than conventional equipment for space cooling, addresses both new and existing commercial buildings, and more effectively controls humidity in humid areas. Waste heat is recovered from the GHP to provide energy for regenerating the desiccant wheel and to augment heating capacity and efficiency. By combining the two technologies, an overall source COP of greater that 1.5 (hot, humid case) can be achieved by utilizing waste heat from the engine to reduce the overall energy required to regenerate the desiccant. Moreover, system modeling results show that the sensible heat ratio (SHR- sensible heat ratio) can be lowered to less 60% in a dedicated outdoor air system application with hot, humid cases.

  7. Laboratory study of subjective perceptions to low temperature heating systems with exhaust ventilation in Nordic countries

    DEFF Research Database (Denmark)

    Jin, Quan; Simone, Angela; Olesen, Bjarne W.

    2017-01-01

    Given the global trends of rising energy demand and the increasing utilization of low-grade renewable energy, low-temperature heating systems can play key roles in improving building energy efficiency while providing a comfortable indoor environment. To meet the need to retrofit existing buildings...

  8. Laboratory study of subjective perceptions to low temperature heating systems with exhaust ventilation in Nordic countries

    DEFF Research Database (Denmark)

    Jin, Quan; Simone, Angela; Olesen, Bjarne W.

    2017-01-01

    Given the global trends of rising energy demand and the increasing utilization of low-grade renewable energy, low-temperature heating systems can play key roles in improving building energy efficiency while providing a comfortable indoor environment. To meet the need to retrofit existing building...

  9. 78 FR 63017 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Science.gov (United States)

    2013-10-23

    ... Aircraft Gas Turbine Engines and Identification Plate for Aircraft Engines AGENCY: Federal Aviation... adopting the gas turbine engine test procedures of the International Civil Aviation Organization (ICAO... regulations, the FAA proposed and the EPA accepted the idea that referring to these engines as exceptions to...

  10. Lightweight Exhaust Manifold and Exhaust Pipe Ducting for Internal Combustion Engines

    Science.gov (United States)

    Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

    1999-01-01

    An improved exhaust system for an internal combustion gasoline-and/or diesel-fueled engine includes an engine exhaust manifold which has been fabricated from carbon- carbon composite materials in operative association with an exhaust pipe ducting which has been fabricated from carbon-carbon composite materials. When compared to conventional steel. cast iron. or ceramic-lined iron paris. the use of carbon-carbon composite exhaust-gas manifolds and exhaust pipe ducting reduces the overall weight of the engine. which allows for improved acceleration and fuel efficiency: permits operation at higher temperatures without a loss of strength: reduces the "through-the wall" heat loss, which increases engine cycle and turbocharger efficiency and ensures faster "light-off" of catalytic converters: and, with an optional thermal reactor, reduces emission of major pollutants, i.e. hydrocarbons and carbon monoxide.

  11. Finite element analysis of radiant heating systems based on gas-fired infrared heat emitters

    Directory of Open Access Journals (Sweden)

    Ermolaev Anton N.

    2017-01-01

    Full Text Available The article presents a finite element model for simulating a gas-fired IR radiation system. Simulation of gaseous combustion and discrete ordinates radiation model were used to solve a number of heat-transfer problems in ventilated rooms with radiant heating. We used Ansys Multiphysics software and Fluent CFD solver for implementing finite element analysis. To solve differential equations of heating and gas dynamics, the following boundary conditions were considered. Dry methane was used as the fuel and air with 21% of oxygen, as oxidizer. Fuel consumption was 0.5 m3/hour; the gas pressure before the nozzle was 1270 Pa. The air–fuel ratio was 9.996.

  12. The effects of inlet temperature and turbulence characteristics on the flow development inside a gas turbine exhaust diffuser

    Science.gov (United States)

    Bomela, Christian Loangola

    The overall industrial gas turbine efficiency is known to be influenced by the pressure recovery in the exhaust system. The design and, subsequently, the performance of an industrial gas turbine exhaust diffuser largely depend on its inflow conditions dictated by the turbine last stage exit flow state and the restraints of the diffuser internal geometry. Recent advances in Computational Fluid Dynamics (CFD) tools and the availability of computer hardware at an affordable cost made the virtual tool a very attractive one for the analysis of fluid flow through devices like a diffuser. In this backdrop, CFD analyses of a typical industrial gas turbine hybrid exhaust diffuser, consisting of an annular diffuser followed by a conical portion, have been carried out with the purpose of improving the performance of these thermal devices using an open-source CFD code "OpenFOAM". The first phase in the research involved the validation of the CFD approach using OpenFOAM by comparing CFD results against published benchmark experimental data. The numerical results closely captured the flow reversal and the separated boundary layer at the shroud wall where a steep velocity gradient has been observed. The standard k --epsilon turbulence model slightly over-predicted the mean velocity profile in the casing boundary layer while slightly under-predicted it in the reversed flow region. A reliable prediction of flow characteristics in this region is very important as the presence of the annular diffuser inclined wall has the most dominant effect on the downstream flow development. The core flow region and the presence of the hub wall have only a minor influence as reported by earlier experimental studies. Additional simulations were carried out in the second phase to test the veracity of other turbulence models; these include RNG k--epsilon, the SST k--o, and the Spalart-Allmaras turbulence models. It was found that a high resolution case with 47.5 million cells using the SST k

  13. 40 CFR 91.423 - Exhaust gas analytical system; CVS grab sample.

    Science.gov (United States)

    2010-07-01

    ... carbon dioxide, and a chemiluminescence detector (CLD) (or heated CLD (HCLD)) for the measurement of... room temperature, produces an equivalent CO response, as measured on the most sensitive CO range, which...

  14. 40 CFR 90.423 - Exhaust gas analytical system; CVS grab sample.

    Science.gov (United States)

    2010-07-01

    ... measurement of carbon monoxide and carbon dioxide, and a chemiluminescence detector (CLD) (or heated CLD (HCLD... room temperature, produces an equivalent CO response, as measured on the most sensitive CO range, which...

  15. Estimation of current density distribution of PAFC by analysis of cell exhaust gas

    Energy Technology Data Exchange (ETDEWEB)

    Kato, S.; Seya, A. [Fuji Electric Co., Ltd., Ichihara-shi (Japan); Asano, A. [Fuji Electric Corporate, Ltd., Yokosuka-shi (Japan)

    1996-12-31

    To estimate distributions of Current densities, voltages, gas concentrations, etc., in phosphoric acid fuel cell (PAFC) stacks, is very important for getting fuel cells with higher quality. In this work, we leave developed a numerical simulation tool to map out the distribution in a PAFC stack. And especially to Study Current density distribution in the reaction area of the cell, we analyzed gas composition in several positions inside a gas outlet manifold of the PAFC stack. Comparing these measured data with calculated data, the current density distribution in a cell plane calculated by the simulation, was certified.

  16. Exergetic analysis and evaluation of a new application of gas engine heat pumps (GEHPs) for food drying processes

    Energy Technology Data Exchange (ETDEWEB)

    Gungor, Aysegul [Department of Mechanical Engineering, Faculty of Engineering, Gediz University, Izmir (Turkey); Erbay, Zafer [Department of Food Engineering, Faculty of Engineering, Ege University, 35100 Izmir (Turkey); Hepbasli, Arif [Department of Mechanical Engineering, Faculty of Engineering, Ege University, 35100 Izmir (Turkey)

    2011-03-15

    In this study, three medicinal and aromatic plants (Foeniculum vulgare, Malva sylvestris L. and Thymus vulgaris) were dried in a pilot scale gas engine driven heat pump drier, which was designed, constructed and installed in Ege University, Izmir, Turkey. Drying experiments were performed at an air temperature of 45 C with an air velocity of 1 m/s. In this work, the performance of the drier along with its main components is evaluated using exergy analysis method. The most important component for improving the system efficiency is found to be the gas engine, followed by the exhaust air heat exchanger for the drying system. An exergy loss and flow diagram (the so-called Grassmann diagram) of the whole drying system is also presented to give quantitative information regarding the proportion of the exergy input dissipated in the various system components, while the sustainability index values for the system components are calculated to indicate how sustainability is affected by changing the exergy efficiency of a process. Gas engine, expansion valve and drying ducts account for more than 60% amount of exergy in the system. The exergetic efficiency values are in the range of 77.68-79.21% for the heat pump unit, 39.26-43.24% for the gas engine driven heat pump unit, 81.29-81.56% for the drying chamber and 48.24-51.28% for the overall drying system. (author)

  17. A review of metallic radiation recuperators for thermal exhaust heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Harshdeep [Galgotias University, Greater Noida (India); Kumar, Anoop; Varun [NIT-Hamirpur, Hamirpur (India); Khurana, Sourabh [Chandigarh University, Chandigarh (India)

    2014-03-15

    Radiation recuperator is a class of indirect contact heat exchanger widely used for waste heat recovery in high temperature industrial applications. At higher temperatures heat loss is higher and as the cost of energy continues to rise, it becomes imperative to save energy and improve overall energy efficiency. In this light, a radiation recuperator becomes a key component in an energy recovery system with great potential for energy saving. Improving recuperator performance, durability, and its design and material considerations has been an ongoing concern. Recent progress in furnace design and micro turbine applications together with use of recuperators has resulted in reduced fuel consumption, increased cost effectiveness and short pay-back time periods. Due to its high commercial value and confidential nature of the industry, little information is available in the open literature as compared to convection recuperators where results are well documented. This review paper intends to bridge the gap in literature and provides valuable information on experimental and theoretical investigations in radiation recuperator development along with identification of some unresolved issues.

  18. Mixing effectiveness test of an exhaust gas mixer in a high bypass turbofan at altitude

    Science.gov (United States)

    Cullom, R. R.; Burkardt, L. A.; Bobula, G. A.

    1981-01-01

    Thermal mixing effectiveness characteristics of an eighteen lobe, scalloped and unscalloped, partial, forced mixer were measured in a high-bypass turbofan engine. Data were also obtained without the mixer installed, i.e. free mixing. Tests were conducted at four combinations of simulated flight conditions from 0.3 to 0.8 Mach number and from 6,096 meters (20,000 ft) to 13,715 m (45,000 ft) altitude. Mixing chamber lengths of L/D = 0.52 and 0.65 were tested. For this range of test conditions and mixer configurations the forced mixing effectiveness varied from 59 to 68 percent. Values of mixing effectiveness and total pressure loss were calculated from temperature and pressure data obtained at the mixer inlet and exhaust nozzle exit.

  19. Relationship between the variations of hydrogen in HCNG fuel and the oxygen in exhausted gas

    OpenAIRE

    Preecha Yaom; Sarawoot Watechagit

    2015-01-01

    The variation of the mixing ratio between hydrogen and compressed natural gas (CNG) in hydrogen enriched compressed natural gas fuel (HCNG) gives different results in terms of engine performances, fuel consumption, and emission characteristics. Therefore, the engine performance using HCNG as fuel can be optimized if the mixing ratio between the two fuels in HCNG can be adjusted in real time while the engine is being operated. In this research, the relationship between the amount of oxygen in ...

  20. Effect of Exhaust Gas Recirculation on Performance of a Diesel Engine Fueled with Waste Plastic Oil / Diesel Blends

    Directory of Open Access Journals (Sweden)

    Punitharani K.

    2017-11-01

    Full Text Available NOx emission is one of the major sources for health issues, acid rain and global warming. Diesel engine vehicles are the major sources for NOx emissions. Hence there is a need to reduce the emissions from the engines by identifying suitable techniques or by means of alternate fuels. The present investigation deals with the effect of Exhaust Gas Recirculation (EGR on 4S, single cylinder, DI diesel engine using plastic oil/Diesel blends P10 (10% plastic oil & 90% diesel in volume, P20 and P30 at various EGR rates. Plastic oil blends were able to operate in diesel engines without any modifications and the results showed that P20 blend had the least NOx emission quantity.

  1. Effects of Exhaust Gas Recirculation on Performance and Emission Characteristic of SI Engine using Hydrogen and CNG Blends

    Science.gov (United States)

    Nitnaware, Pravin Tukaram; Suryawanshi, Jiwak G.

    2018-01-01

    This paper shows exhaust gas recirculation (EGR) effects on multi-cylinder bi-fuel SI engine using blends of 0, 5, 10 and 15% hydrogen by energy with CNG. All trials are performed at a speed of 3000, 3500 and 4000 rpm with EGR rate of 0, 5, 10 and 15%, with equal spark timing and injection pressure of 2.6 bar. At specific hydrogen percentage with increase in EGR rate NOx emission reduces drastically and increases with increase in hydrogen addition. Hydrocarbon (HC) and carbon monoxide (CO) emission decreases with increase in speed and hydrogen addition. There is considerable improvement in brake thermal efficiency (BTE) and brake specific energy consumption (BSEC) at 15% EGR rate. At 3000 rpm, 5% EGR rate with 5% hydrogen had shown maximum cylinder pressure. Brake specific fuel consumption (b.s.f.c) increased with increase in EGR rate and decreased with increase in hydrogen addition for all speeds.

  2. Enhancing efficiency and power output of gas turbines using either renewable energy or heat recovery cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Nasser, A.E.M. [Higher Technological Inst., Tenth of Ramadan (Egypt). Dept. of Mechanical Engineering

    2006-07-01

    An absorption system to cool intake air to the compressor of an air conditioning system was presented. The system used both solar energy and the waste heat of the exhaust gases to obtain higher temperatures during the summer months. The lithium bromide-water absorption system increased power output by more than 20 per cent during the summer months without consuming more fuel. The system was designed to conserve energy and output power in gas turbine power stations. The system operated by using hot effluent gases leaving the turbine and entered the flue stacks, where heat exchangers recovered the heat energy. Excess electricity produced by the turbine was then used to cool the ambient air before it entered the compressor. Studies have confirmed that the system is financially viable and suited for use in Arabian Gulf countries where temperatures regularly exceed 40 degrees C. 6 refs., 6 figs.

  3. Optimization of the Heating Element in a Gas-Gas Heater Using an Integrated Analysis Model

    Directory of Open Access Journals (Sweden)

    Young Mun Lee

    2017-11-01

    Full Text Available Gas-gas heaters (GGHs are used to reheat gases through desulfurization in coal-fired power plants to reduce low-temperature corrosion and white smoke. Wrinkled heating elements are installed inside the GGH to perform effective heat exchange. An optimization study of the heating element shape was conducted to reduce the differential pressure effectively and improve performance. An integrated analysis model was applied. Based on actual operational data, a computational fluid dynamic analysis was conducted on the L-type heating element and GGH system. The experiments applied the optimal latin hypercube sampling method, and numerical analysis was performed for each sample. Based on the response surface, the result of the sample was optimized through the pointer algorithm. For the integrated analysis model, validation was performed by comparison with the actual operational data, and the thermal-fluid characteristics of the heating element and GGH system were analyzed to set three parameters: plate angle, undulated angle, and pitch 1. From the optimization result, increases in the undulated angle and pitch 1 reduce the pressure drop by widening the heating element cross section. By increasing the plate angle, the heat transfer area is secured and the reduced heat transfer coefficient is compensated, improving the GGH performance.

  4. The origin of the hot metal-poor gas in NGC 1291 - Testing the hypothesis of gas dynamics as the cause of the gas heating

    NARCIS (Netherlands)

    Perez, [No Value; Freeman, K

    In this paper we test the idea that the low-metallicity hot gas in the centre of NGC 1291 is heated via a dynamical process. In this scenario, the gas from the outer gas-rich ring loses energy through bar-driven shocks and falls to the centre. Heating of the gas to X-ray temperatures comes from the

  5. Comparative evaluation of the impacts of domestic gas and electric heat pump heating on air pollution in California

    Energy Technology Data Exchange (ETDEWEB)

    Ganji, A. (San Francisco State Univ., CA (United States). Div. of Engineering)

    1992-07-01

    Residential space and water heating accounts for approximately 12% of California's and 15% of the United States, energy consumption. most Of the residential heating is by direct use of natural gas. combustion of natural gas is a contributor to the overall air pollution,, especially CO and NO{sub x} in the urban areas. Another efficient method for domestic water and space heating is use of electric heat pumps, the most popular category of which uses air as its heat source. Electric heat pumps do not emit air pollutants at the point of use, but use electric power, which is a major contributor to air pollution at its point of generation from fossil fuels. It is the specific objective of this report to evaluate and compare the energy efficiency and source air pollutants of natural gas heaters and electric heat pumps used for domestic heating. Effect of replacing natural gas heaters with electric heat pumps on air pollutant emissions due to domestic heating in two urban areas and in California as a whole has also been evaluated. The analysis shows that with the present state of technology, electric heat pumps have higher heating efficiencies than natural gas heaters. Considering the current electricity generation mix in the US, electric heat pumps produce two to four times more NO{sub x}, much less CO, and comparable amount of CO{sub 2} per unit of useful heating energy compared to natural gas heaters. With California mix, electric heat pumps produce comparable NO{sub x} and much less CO and approximately 30% less CO{sub 2} per unit heat output. Replacement of natural gas heaters with electric heat pumps will slightly increase the overall NO{sub x}, and reduce CO and CO{sub 2} emissions in California. The effect of advanced technology power generation and heat pump heating has also been analyzed.

  6. Comparative evaluation of the impacts of domestic gas and electric heat pump heating on air pollution in California. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ganji, A. [San Francisco State Univ., CA (United States). Div. of Engineering

    1992-07-01

    Residential space and water heating accounts for approximately 12% of California`s and 15% of the United States, energy consumption. most Of the residential heating is by direct use of natural gas. combustion of natural gas is a contributor to the overall air pollution,, especially CO and NO{sub x} in the urban areas. Another efficient method for domestic water and space heating is use of electric heat pumps, the most popular category of which uses air as its heat source. Electric heat pumps do not emit air pollutants at the point of use, but use electric power, which is a major contributor to air pollution at its point of generation from fossil fuels. It is the specific objective of this report to evaluate and compare the energy efficiency and source air pollutants of natural gas heaters and electric heat pumps used for domestic heating. Effect of replacing natural gas heaters with electric heat pumps on air pollutant emissions due to domestic heating in two urban areas and in California as a whole has also been evaluated. The analysis shows that with the present state of technology, electric heat pumps have higher heating efficiencies than natural gas heaters. Considering the current electricity generation mix in the US, electric heat pumps produce two to four times more NO{sub x}, much less CO, and comparable amount of CO{sub 2} per unit of useful heating energy compared to natural gas heaters. With California mix, electric heat pumps produce comparable NO{sub x} and much less CO and approximately 30% less CO{sub 2} per unit heat output. Replacement of natural gas heaters with electric heat pumps will slightly increase the overall NO{sub x}, and reduce CO and CO{sub 2} emissions in California. The effect of advanced technology power generation and heat pump heating has also been analyzed.

  7. Experimental Research On Gas Injection High Temperature Heat Pump With An Economizer

    OpenAIRE

    He, Yongning; Jin, Lei; Cao, Feng; Chen, Shengkun

    2014-01-01

    Gas injection technology is often used in cold regions to solve heat pump’s low heating capacity and high discharge temperature at low ambient temperature. Injecting gas into port opened at specific position of compressor could increase mass flow rate of compressor and total heating capacity of heat pump. Gas injection also changes compression ratio of compressor and decreases discharge temperature. An optimal gas injection pressure is got when the coefficient of performance reached to peak v...

  8. Find surface heat loss and flue gas density quickly

    Energy Technology Data Exchange (ETDEWEB)

    Chanapathy, V.

    1985-04-01

    Tables and charts are presented for quick estimates of heat loss from insulated surfaces and flue gas density for various fossil fuels. Two types of problems faced by thermal engineers are presented. Both types of problems can be handled. An advantage of the chart is that for a wide range of surface and ambient temperatures ..gamma.. may be determined. This situation is common in industrial practice where wind velocity and ambient temperatures vary significantly over a period of time.

  9. Risk Based Inspection of Gas-Cooling Heat Exchanger

    Directory of Open Access Journals (Sweden)

    Dwi Priyanta

    2017-09-01

    Full Text Available On October 2013, Pertamina Hulu Energi Offshore North West Java (PHE – ONWJ platform personnel found 93 leaking tubes locations in the finfan coolers/ gas-cooling heat exchanger. After analysis had been performed, the crack in the tube strongly indicate that stress corrosion cracking was occurred by chloride. Chloride stress corrosion cracking (CLSCC is the cracking occurred by the combined influence of tensile stress and a corrosive environment. CLSCC is the one of the most common reasons why austenitic stainless steel pipework or tube and vessels deteriorate in the chemical processing, petrochemical industries and maritime industries. In this thesis purpose to determine the appropriate inspection planning for two main items (tubes and header box in the gas-cooling heat exchanger using risk based inspection (RBI method. The result, inspection of the tubes must be performed on July 6, 2024 and for the header box inspection must be performed on July 6, 2025. In the end, RBI method can be applicated to gas-cooling heat exchanger. Because, risk on the tubes can be reduced from 4.537 m2/year to 0.453 m2/year. And inspection planning for header box can be reduced from 4.528 m2/year to 0.563 m2/year.

  10. Regulated and unregulated exhaust gas components from LD vehicles on petrol, diesel, LPG and CNG

    NARCIS (Netherlands)

    Hendriksen, P.; Rijkeboer, R.C.

    1993-01-01

    Four fuels (petrol, LPG, CNG and diesel) are compared on passenger cars and lighter vans. The comparisons are made for the usual regulated components, but also for a number of unregulated components. The project was financed by the Dutch government, the association of gas suppliers, a number of

  11. Impact of intake CO 2 addition and exhaust gas recirculation on NO x emissions and soot reactivity in a common rail diesel engine

    KAUST Repository

    Al-Qurashi, Khalid

    2012-10-18

    The impact of intake CO 2 addition and exhaust gas recirculation (EGR) on engine combustion characteristics, NO x emissions, and soot oxidative reactivity was studied in a common rail diesel engine equipped with a cooled EGR system. The engine test results and the heat release analysis show that the reduced flame temperature, induced by the reduction of the oxygen concentration (dilution effect) is the dominant mechanism via which CO 2 and EGR lower NO x emissions in diesel engines. On the other hand, the collected soot from the engine tests was examined for its oxidative reactivity using a thermogravimetric analyzer (TGA). Results show that EGR has a significant effect on soot reactivity and results in higher initial active sites compared to the CO 2 case. We conclude that the reduced flame temperature (thermal effect) which is a consequence of the dilution effect is responsible for the observed increase in soot reactivity. These results confirm observations from our past work on flame soot, which showed that the peak adiabatic flame temperature is the governing factor affecting soot reactivity. These findings imply that driving the combustion concepts toward low temperature is favorable to effectively control engine pollutants, including soot reactivity. © 2012 American Chemical Society.

  12. Instabilities during the NO-reduction of oxygen-containing exhaust gas using hydrogen. Instabilitaeten bei der NO-Reduktion in sauerstoffhaltigen Abgasen mit Sauerstoff

    Energy Technology Data Exchange (ETDEWEB)

    Rogowski, A. (Technische Univ. Berlin (Germany). Inst. fuer Thermodynamik und Reaktionstechnik)

    1993-05-01

    By means of measurements it was demonstrated that nitric oxides can be reduced within an oxygen-containing exhaust gas using hydrogen. During the NO-reduction, though, certain phenomena arise: within a distinct range of operation parameters oscillations of the conversion rate [alpha][sub NO] and [alpha][sub H[sub -

  13. Influence of cooled exhaust gas recirculation on performance, emissions and combustion characteristics of LPG fuelled lean burn SI engine

    Science.gov (United States)

    Ravi, K.; Pradeep Bhasker, J.; Alexander, Jim; Porpatham, E.

    2017-11-01

    On fuel perspective, Liquefied Petroleum Gas (LPG) provides cleaner emissions and also facilitates lean burn signifying less fuel consumption and emissions. Lean burn technology can attain better efficiencies and lesser combustion temperatures but this temperature is quite sufficient to facilitate formation of nitrogen oxide (NOx). Exhaust Gas Recirculation (EGR) for NOx reduction has been considered allover but extremely little literatures exist on the consequence of EGR on lean burn LPG fuelled spark ignition (SI) engine. The following research is carried out to find the optimal rate of EGR addition to reduce NOx emissions without settling on performance and combustion characteristics. A single cylinder diesel engine is altered to operate as LPG fuelled SI engine at a compression ratio of 10.5:1 and arrangements to provide different ratios of cooled EGR in the intake manifold. Investigations are done to arrive at optimum ratio of the EGR to reduce emissions without compromising on performance. Significant reductions in NOx emissions alongside HC and CO emissions were seen. Higher percentages of EGR further diluted the charge and lead to improper combustion and thus increased hydrocarbon emissions. Cooled EGR reduced the peak in-cylinder temperature which reduced NOx emissions but lead to misfire at lower lean limits.

  14. Fuel-air mixing apparatus for reducing gas turbine combustor exhaust emissions

    Science.gov (United States)

    Zupanc, Frank J. (Inventor); Yankowich, Paul R. (Inventor)

    2006-01-01

    A fuel-air mixer for use in a combustion chamber of a gas turbine engine is provided. The fuel air mixing apparatus comprises an annular fuel injector having a plurality of discrete plain jet orifices, a first swirler wherein the first swirler is located upstream from the fuel injector and a second swirler wherein the second swirler is located downstream from the fuel injector. The plurality of discrete plain jet orifices are situated between the highly swirling airstreams generated by the two radial swirlers. The distributed injection of the fuel between two highly swirling airstreams results in rapid and effective mixing to the desired fuel-air ratio and prevents the formation of local hot spots in the combustor primary zone. A combustor and a gas turbine engine comprising the fuel-air mixer of the present invention are also provided as well as a method using the fuel-air mixer of the present invention.

  15. Correlation of gas exchange threshold and first muscle oxyhemoglobin inflection point with time-to-exhaustion during heavy-intensity exercise.

    Science.gov (United States)

    Coquart, Jérémy B; Mucci, Patrick; L'hermette, Maxime; Chamari, Karim; Tourny, Claire; Garcin, Murielle

    2017-03-01

    The twofold aim of the study was to: 1) compare the gas exchange threshold (GET), the first oxyhemoglobin inflection point ([O2Hb]-T), and perceptual threshold as determined during an incremental exercise test, and 2) investigate the link between each threshold and time-to-exhaustion during heavy intensity exercise. Fourteen competitive cyclists performed an incremental exercise test to exhaustion on a cycloergometer to determine the different thresholds and peak workload (Wpeak). The participants then performed a sub-maximal constant workload test (90% Wpeak) to exhaustion to determine time-to-exhaustion. The thresholds were identified from: 1) the first breakpoint in the oxygen uptake vs. carbon dioxide output curve (GET), 2) the [O2Hb]-T, and 3) a rating of 13 in perceived exertion (perceptual threshold: RPE13-T). Oxygen uptake at the different thresholds was not significantly different (P>0.05). Moreover, GET and [O2Hb]-T were significantly correlated: 1) to each other (r≥0.79; P≤0.001), and 2) to time-to-exhaustion (r=0.81 and r=0.72, respectively; Pexhaustion (P=0.148). The anaerobic threshold as identified from GET was concomitant to [O2Hb]-T. Both thresholds were correlated to time-to-exhaustion, and could therefore be used as a performance index in middle-duration events.

  16. Atmospheric pressure glow discharge generated in nitrogen-methane gas mixture: PTR-MS analyzes of the exhaust gas

    Science.gov (United States)

    Torokova, Lucie; Mazankova, Vera; Krcma, Frantisek; Mason, Nigel J.; Matejcik, Stefan

    2015-07-01

    This paper reports the results of an extensive study of with the in situ mass spectrometry analysis of gaseous phase species produced by an atmospheric plasma glow discharge in N2-CH4 gas mixtures (with methane concentrations ranging from 1% to 4%). The products are studied using proton-transfer-reaction mass spectrometry (PTR-MS). HCN and CH3CN are identified as the main gaseous products. Hydrazine, methanimine, methyldiazene, ethylamine, cyclohexadiene, pyrazineacetylene, ethylene, propyne and propene are identified as minor compounds. All the detected compounds and their relative abundances are determined with respect to the experimental conditions (gas composition and applied power). The same molecules were observed by the Cassini-Huygens probe in Titan's atmosphere (which has same N2-CH4 gas mixtures). Such, experiments show that the formation of such complex organics in atmospheres containing C, N and H, like that of Titan, could be a source of prebiotic molecules. Contribution to the topical issue "The 14th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XIV)", edited by Nicolas Gherardi, Ronny Brandenburg and Lars Stollenwark

  17. Influence of Compressor Station Waste-Heat Recovery Section on Operational Efficiency of Gas Turbine Drive with Isobaric Heat Supply and Regenerative Heat Utilization

    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk

    2013-01-01

    Full Text Available The possibility to utilize existing secondary energy resources for heat supply of an industrial enterprise has been proposed on the basis of the analysis on operation of compressor stations of a cross-country gas pipe-line. The paper considers an influence of waste heat recovery section on operational efficiency of gas turbine drive with regenerative heat utilization.

  18. Storage of Nitrous Oxide (NOx in Diesel Engine Exhaust Gas using Alumina-Based Catalysts: Preparation, Characterization, and Testing

    Directory of Open Access Journals (Sweden)

    A. Alsobaai

    2017-03-01

    Full Text Available This work investigated the nitrous oxide (NOx storage process using alumina-based catalysts (K2 O/Al2 O3 , CaO/Al2 O3,  and BaO/Al2 O3 . The feed was a synthetic exhaust gas containing 1,000 ppm of nitrogen monoxide (NO, 1,000 ppm i-C4 H10 , and an 8% O2  and N2  balance. The catalyst was carried out at temperatures between 250–450°C and a contact time of 20 minutes. It was found that NOx was effectively adsorbed in the presence of oxygen. The NOx storage capacity of K2 O/Al2 O3 was higher than that of BaO/Al2 O3.  The NOx storage capacity for K2 O/Al2 O3  decreased with increasing temperature and achieved a maximum at 250°C. Potassium loading higher than 15% in the catalyst negatively affected the morphological properties. The combination of Ba and K loading in the catalyst led to an improvement in the catalytic activity compared to its single metal catalysts. As a conclusion, mixed metal oxide was a potential catalyst for de-NOx process in meeting the stringent diesel engine exhaust emissions regulations. The catalysts were characterized by a number of techniques and measurements, such as X-ray diffraction (XRD, electron affinity (EA, a scanning electron microscope (SEM, Brunner-Emmett-Teller (BET to measure surface area, and pore volume and pore size distribution assessments.

  19. Gas Turbine Engine Having Fan Rotor Driven by Turbine Exhaust and with a Bypass

    Science.gov (United States)

    Suciu, Gabriel L. (Inventor); Chandler, Jesse M. (Inventor)

    2016-01-01

    A gas turbine engine has a core engine incorporating a core engine turbine. A fan rotor is driven by a fan rotor turbine. The fan rotor turbine is in the path of gases downstream from the core engine turbine. A bypass door is moveable from a closed position at which the gases from the core engine turbine pass over the fan rotor turbine, and moveable to a bypass position at which the gases are directed away from the fan rotor turbine. An aircraft is also disclosed.

  20. Mutagenicity of diesel engine exhaust is eliminated in the gas phase by an oxidation catalyst but only slightly reduced in the particle phase.

    Science.gov (United States)

    Westphal, Götz A; Krahl, Jürgen; Munack, Axel; Ruschel, Yvonne; Schröder, Olaf; Hallier, Ernst; Brüning, Thomas; Bünger, Jürgen

    2012-06-05

    Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced

  1. Recommended launch-hold criteria for protecting public health from hydrogen chloride (HC1) gas produced by rocket exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J.I.; Baskett, R.L.

    1995-11-01

    Solid-fuel rocket motors used by the United States Air Force (USAF) to launch missiles and spacecraft can produce ambient-air concentrations of hydrogen chloride (HCI) gas. The HCI gas is a reaction product exhausted from the rocket motor during normal launch or emitted as a result of a catastrophic abort destroying the launch vehicle. Depending on the concentration in ambient air, the HCI gas can be irritating or toxic to humans. The diagnostic and complex-terrain wind field and particle dispersion model used by the Lawrence Livermore National Laboratory`s (LLNL`s) Atmospheric Release Advisory Capability (ARAC) Program was applied to the launch of a Peacekeeper missile from Vandenberg Air Force Base (VAFB) in California. Results from this deterministic model revealed that under specific meteorological conditions, cloud passage from normal-launch and catastropic-abort situations can yield measureable ground-level air concentrations of HCI where the general public is located. To protect public health in the event of such cloud passage, scientifically defensible, emergency ambient-air concentration limits for HCI were developed and recommended to the USAF for use as launch-hold criteria. Such launch-hold criteria are used to postpone a launch unless the forecasted meteorological conditions favor the prediction of safe ground-level concentrations of HCl for the general public. The recommended concentration limits are a 2 ppM 1-h time-weighted average (TWA) concentration constrained by a 1-min 10-ppM average concentration. This recommended criteria is supported by human dose-response information, including data for sensitive humans (e.g., asthmatics), and the dose response exhibited experimentally by animal models with respiratory physiology or responses considered similar to humans.

  2. Experimental Study on the Absorption of Toluene from Exhaust Gas by Paraffin/Surfactant/Water Emulsion

    Directory of Open Access Journals (Sweden)

    Ping Fang

    2016-01-01

    Full Text Available A new paraffin/surfactant/water emulsion (PSW for volatile organic compounds (VOCs controlling was prepared and its potential for VOCs removal was investigated. Results indicated that PSW-5 (5%, v/v provided higher toluene absorption efficiency (90.77% than the other absorbents used. The saturation pressure, Henry’s constant, and activity coefficient of toluene in PSW-5 were significantly lower than those in water, and toluene solubility (1.331 g·L−1 in the PSW-5 was more than 2.5 times higher than the value in water. Several factors potentially affecting the toluene absorption efficiency were systematically investigated. The results suggested that concentration and pH of PSW, absorption temperature, and gas flow rate all had a strong influence on the toluene absorption, but the inlet concentration of toluene had little effect on the toluene absorption. There were different absorbing performances of PSW-5 on different VOCs, and the ketones, esters, and aromatics were more easily removed by the PSW-5 than the alkanes. Regeneration and reuse of the PSW were possible; after 3 runs of regeneration the absorption efficiency of PSW-5 for toluene also could reach 82.42%. So, the PSW is an economic, efficient, and safe absorbent and has a great prospect in organic waste gas treatment.

  3. Solar thermal energy / exhaust air heat pump / wood pellet furnace for a sustainable heat supply of low energy buildings in older buildings; Solarthermie / Abluft-Waermepumpe / Pelletofen. Kombisysteme zur nachhaltigen Waermeversorgung von Niedrigenergiehaeusern im Gebaeudebestand

    Energy Technology Data Exchange (ETDEWEB)

    Diefenbach, Nikolaus; Born, Rolf [Institut Wohnen und Umwelt GmbH, Darmstadt (Germany); Staerz, Norbert [Ingenieurbuero inPlan, Pfungstadt (Germany)

    2009-11-13

    The research project under consideration reports on combination systems for a sustainable heat supply for low-energy buildings in older building. For this, a central and decentralized system configuration consisting of solar thermal energy, exhaust air heat pump and wood pellet furnace are presented. Solutions for an interaction of these three heat suppliers in one plant are designated regarding the control strategy. The fundamentals of the computerized simulations for the central and decentralized system are presented. A cost estimate with both variants of the combination system as well as a comparison with conventional energy-saving heat supply systems follow.

  4. CONVECTIVE HEAT TRANSFER IN CYCLONE DEVICE WITH EXTERNAL GAS RECIRCULATION

    Directory of Open Access Journals (Sweden)

    S. V. Karpov

    2016-01-01

    Full Text Available The article considers the convective heat transfer on the surface of a hollow cylinder or several billets in a cyclone device with the new principle of external gas recirculation. According to this principle, transport of coolant from the lateral surface of the chamber, where the temperature is the highest, in the axial region is being fulfilled due to the pressure drop between the wall and axial areas of cyclonic flow. Dependency analysis of average and local heat transfer coefficients from operational and geometrical parameters has been performed; the generalized similarity equations for the calculation of the latter have been suggested. It is demonstrated that in case of download of a cyclone chamber with several billets, the use of the considered scheme of the external recirculation due to the specific characteristics of aerodynamics practically does not lead to noticeable changes in the intensity of convective heat transfer. Both experimental data and the numerical simulation results obtained with the use of OpenFOAM platform were used in the work. The investigations fulfilled will expand the area of the use of cyclone heating devices.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-15

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

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

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper

    2008-01-01

    different measuring methods. Likewise, no particles were detected in the gas. Considerable amounts of NH3 were measured in the produced gas.An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging......The aim of this project has been the characterization of biomass producer gas as a fuel for stationary gas engines in heat and power production. More than 3200 hours of gas engine operation, with producer gas as fuel, has been conducted at the biomass gasification combined heat and power (CHP...

  7. High Temperature Gas-to-Gas Heat Exchanger Based on a Solid Intermediate Medium

    Directory of Open Access Journals (Sweden)

    R. Amirante

    2014-04-01

    Full Text Available This paper proposes the design of an innovative high temperature gas-to-gas heat exchanger based on solid particles as intermediate medium, with application in medium and large scale externally fired combined power plants fed by alternative and dirty fuels, such as biomass and coal. An optimization procedure, performed by means of a genetic algorithm combined with computational fluid dynamics (CFD analysis, is employed for the design of the heat exchanger: the goal is the minimization of its size for an assigned heat exchanger efficiency. Two cases, corresponding to efficiencies equal to 80% and 90%, are considered. The scientific and technical difficulties for the realization of the heat exchanger are also faced up; in particular, this work focuses on the development both of a pressurization device, which is needed to move the solid particles within the heat exchanger, and of a pneumatic conveyor, which is required to deliver back the particles from the bottom to the top of the plant in order to realize a continuous operation mode. An analytical approach and a thorough experimental campaign are proposed to analyze the proposed systems and to evaluate the associated energy losses.

  8. Influence of collector heat capacity and internal conditions of heat exchanger on cool-down process of small gas liquefier

    Science.gov (United States)

    Saberimoghaddam, Ali; Bahri Rasht Abadi, Mohammad Mahdi

    2018-01-01

    Joule-Thomson cooling systems are commonly used in gas liquefaction. In small gas liquefiers, transient cool-down time is high. Selecting suitable conditions for cooling down process leads to decrease in time and cost. In the present work, transient thermal behavior of Joule-Thomson cooling system including counter current helically coiled tube in tube heat exchanger, expansion valve, and collector was studied using experimental tests and simulations. The experiments were performed using small gas liquefier and nitrogen gas as working fluid. The heat exchanger was thermally studied by experimental data obtained from a small gas liquefier. In addition, the simulations were performed using experimental data as variable boundary conditions. A comparison was done between presented and conventional methods. The effect of collector heat capacity and convection heat transfer coefficient inside the tubes on system performance was studied using temperature profiles along the heat exchanger.

  9. Effects of chronic exposure to diluted automotive exhaust gas on the CNS of normotensive and hypertensive rats.

    Science.gov (United States)

    Roggendorf, W; Thron, N L; Ast, D; Köhler, P R

    1981-01-01

    Regarding the potential impact of traffic-born air pollutants on public health, attention during the last years has been increasingly focused on the possible effects in high-risk groups of the population. In order to evaluated this point further, the combined influence of both, chronic arterial hypertension and long-time exhaust gas exposure on the CNS has been studied. Both, normotensive Wistar) and spontaneously hypertensive rats (SHR) of either sex were exposed 5 X 8 hours per week for up to 18 months to atmospheres polluted by the emissions of an idling Otto engine with CO concentrations held constant at about 0,90 and 250 ppm, respectively. Biochemical data, body weight, and blood pressure were checked regularly. Characteristic histomorphological findings in the non-exposed SHR brains were hyalinosis and hyperplasia of intracerebral arterioles and -- in some cases -- small focal hemorrhages and infarcts. In the exposed SHR brains, large infarcts of the hemisphere and in the basal ganglia were found, which possibly corresponds to the increase of the mortality rate in SHR. We assume that the increase hematocrit plays an important role in the disturbance of microcirculation of the CNS.

  10. Numerical analysis of C.I engine to control emissions using exhaust gas recirculation and advanced start of inject

    Directory of Open Access Journals (Sweden)

    P. Kashyap Chowdary

    2016-06-01

    Full Text Available As major limitation of diesel engines is the high soot and nitrogen oxide emissions which cannot be reduced totally with only conventional catalytic converters today, varying fuel characteristics became a focus of interest to meet the pollution emission legislations as they require very few or no changes in existing engine model. The present work deals with, numerical analysis of combined effect of Advanced Start of Injection (SOI and Exhaust Gas Re-circulation (EGR on performance and emissions which were studied, by performing numerical analysis on a Caterpillar 3401 single cylinder C.I engine model at constant speed using diesel as fuel via three dimensional computational fluid dynamics (CFD procedures and validated with experimental data. The SOI is advanced from 11° Crank angle bTDC to 14.5° Crank angle bTDC and EGR as a fraction is increased from 0% to 10%. The modified conditions of these parameters resulted in simultaneous reduction of NOx and Soot.

  11. An Approach to the Prototyping of an Optimized Limited Stroke Actuator to Drive a Low Pressure Exhaust Gas Recirculation Valve

    Directory of Open Access Journals (Sweden)

    Christophe Gutfrind

    2016-05-01

    Full Text Available The purpose of this article is to describe the design of a limited stroke actuator and the corresponding prototype to drive a Low Pressure (LP Exhaust Gas Recirculation (EGR valve for use in Internal Combustion Engines (ICEs. The direct drive actuator topology is an axial flux machine with two air gaps in order to minimize the rotor inertia and a bipolar surface-mounted permanent magnet in order to respect an 80° angular stroke. Firstly, the actuator will be described and optimized under constraints of a 150 ms time response, a 0.363 N·m minimal torque on an angular range from 0° to 80° and prototyping constraints. Secondly, the finite element method (FEM using the FLUX-3D® software (CEDRAT, Meylan, France will be used to check the actuator performances with consideration of the nonlinear effect of the iron material. Thirdly, a prototype will be made and characterized to compare its measurement results with the analytical model and the FEM model results. With these electromechanical behavior measurements, a numerical model is created with Simulink® in order to simulate an EGR system with this direct drive actuator under all operating conditions. Last but not least, the energy consumption of this machine will be estimated to evaluate the efficiency of the proposed EGR electromechanical system.

  12. Study on Gas-liquid Falling Film Flow in Internal Heat Integrated Distillation Column

    Science.gov (United States)

    Liu, Chong

    2017-10-01

    Gas-liquid internally heat integrated distillation column falling film flow with nonlinear characteristics, study on gas liquid falling film flow regulation control law, can reduce emissions of the distillation column, and it can improve the quality of products. According to the distribution of gas-liquid mass balance internally heat integrated distillation column independent region, distribution model of heat transfer coefficient of building internal heat integrated distillation tower is obtained liquid distillation falling film flow in the saturated vapour pressure of liquid water balance, using heat transfer equation and energy equation to balance the relationship between the circulating iterative gas-liquid falling film flow area, flow parameter information, at a given temperature, pressure conditions, gas-liquid flow falling film theory makes the optimal parameters to achieve the best fitting value with the measured values. The results show that the geometric gas-liquid internally heat integrated distillation column falling film flow heat exchange area and import column thermostat, the average temperature has significant. The positive correlation between the heat exchanger tube entrance due to temperature difference between inside and outside, the heat flux is larger, with the increase of internal heat integrated distillation column temperature, the slope decreases its temperature rise, which accurately describes the internal gas-liquid heat integrated distillation tower falling film flow regularity, take appropriate measures to promote the enhancement of heat transfer. It can enhance the overall efficiency of the heat exchanger.

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

    Science.gov (United States)

    Ernst, Timothy C.; Nelson, Christopher R.

    2014-06-17

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

  14. 40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.

    Science.gov (United States)

    2010-07-01

    ... collected for analysis. Mass emissions are determined from the sample concentration and total flow over the test period. (2) Engine exhaust to CVS duct. For methanol-fueled engines, reactions of the exhaust...), as applicable are achieved by sampling at a constant flow rate. For methanol-fueled engines, the...

  15. Carbon nanotube-like materials in the exhaust from a diesel engine using gas oil/ethanol mixing fuel with catalysts and sulfur.

    Science.gov (United States)

    Suzuki, Shunsuke; Mori, Shinsuke

    2017-08-01

    Particulate matter from a diesel engine, including soot and carbon nanomaterials, was collected on a sampling holder and the structure of the materials was studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). As a result of employing gas oil/ethanol mixing fuel with sulfur and ferrocene/molybdenum as catalyst sources, formation of carbon nanotubes (CNT)-like materials in addition to soot was observed in the exhaust gas from a diesel engine. It was revealed that CNT-like materials were included among soot in our system only when the following three conditions were satisfied simultaneously: high ethanol fraction in fuel, high sulfur loading, and presence of catalyst sources in fuel. This study confirmed that if at least one of these three conditions was not satisfied, CNT-like materials were not observed in the exhaust from a diesel engine. These experimental results shown in this work provide insights into understanding CNT-like material formation mechanism in a diesel engine. Recent papers reported that carbon nanotube-like materials were included in the exhaust gas from engines, but conditions for carbon nanotube-like material formation have not been well studied. This work provides the required conditions for carbon nanotube-like material growth in a diesel engine, and this will be helpful for understanding the carbon nanotube-like material formation mechanism and taking countermeasures to preventing carbon nanotube-like material formation in a diesel engine.

  16. Energy recovery during expansion of compressed gas using power plant low-quality heat sources

    Science.gov (United States)

    Ochs, Thomas L [Albany, OR; O'Connor, William K [Lebanon, OR

    2006-03-07

    A method of recovering energy from a cool compressed gas, compressed liquid, vapor, or supercritical fluid is disclosed which includes incrementally expanding the compressed gas, compressed liquid, vapor, or supercritical fluid through a plurality of expansion engines and heating the gas, vapor, compressed liquid, or supercritical fluid entering at least one of the expansion engines with a low quality heat source. Expansion engines such as turbines and multiple expansions with heating are disclosed.

  17. Determination of benzene in exhaust gas from biofuels. Final report; Bestimmung von Benzol im Abgas von Biokraftstoffen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Dutz, M.; Buenger, J.; Gnuschke, H.; Halboth, H.; Gruedl, P.; Krahl, J.

    2001-10-01

    With the advance of environmental legislation and practices oriented towards sustainability renewable energy resources are becoming increasingly important. Use of replenishable raw materials helps preserve fossil resources. In the fuel sector the most widely used replenishable materials are rape methyl ester (RME) and ethyl tertiary butyl ether (ETBE). The purpose of the present project on the ''Determination of benzene in exhaust gas from biofuels'' was to generate orienting data on the potential health relevance of mixtures of fossil and renewable fuel intended for use in spark ignition and diesel engines. This included a determination of benzene emissions and the mutagenicity of particles. Beyond the applied-for scope of research measurements were also performed on the test engine's toluene, ethyl benzene and xylene emissions as well as on the smoke spot number and nitrogen oxide (NO{sub x}) and hydrocarbon (HC) emissions of the diesel engine. [German] Regenerative Energien gewinnen durch die Umweltgesetzgebungen und das Streben nach einer nachhaltigen Entwicklung zunehmend an Bedeutung. Durch die Verwendung nachwachsender Rohstoffe koennen die fossilen Ressourcen geschont werden. Im Kraftstoffsektor sind hier hauptsaechlich Rapsoelmethylester (RME) und optional Ethyltertiaerbutylether (ETBE) zu nennen. Um fuer Diesel- und Ottomotoren insbesondere mit Blick auf Kraftstoffgemische aus fossilen und regenerativen Komponenten orientierende Daten ueber eine potenzielle Gesundheitsrelevanz zu generieren, wurde das Projekt 'Bestimmung von Benzol im Abgas von Biokraftstoffen' durchgefuehrt. Neben der Benzolemission wurde die Mutagenitaet der Partikeln ermittelt. Ueber den beantragten Untersuchungsrahmen hinaus wurden die Tuluol-, Ethylbenzol-, und Xylolemissionen der eingesetzten Motoren, sowie die Russzahl (RZ) und die Stickoxid- (NO{sub x}) und Kohlenwasserstoffemissionen (HC) des Dieselmotors bestimmt. (orig.)

  18. Emission and performance analysis on the effect of exhaust gas recirculation in alcohol-biodiesel aspirated research diesel engine.

    Science.gov (United States)

    Mahalingam, Arulprakasajothi; Munuswamy, Dinesh Babu; Devarajan, Yuvarajan; Radhakrishnan, Santhanakrishnan

    2018-02-21

    In this study, the effect of blending pentanol to biodiesel derived from mahua oil on emissions and performance pattern of a diesel engine under exhaust gas recirculation (EGR) mode was examined and compared with diesel. The purpose of this study is to improve the feasibility of employing biofuels as a potential alternative in an unmodified diesel engine. Two pentanol-biodiesel blends denoted as MOBD90P10 and MOBD80P20 which matches to 10 and 20 vol% of pentanol in biodiesel, respectively, were used as fuel in research engine at 10 and 20% EGR rates. Pentanol is chosen as a higher alcohol owing to its improved in-built properties than the other first-generation alcohols such as ethanol or methanol. Experimental results show that the pentanol and biodiesel blends (MOBD90P10 and MOBD80P20) have slightly higher brake thermal efficiency (0.2-0.4%) and lower brake-specific fuel consumption (0.6 to 1.1%) than that of neat biodiesel (MOBD100) at all engine loads. Nitrogen oxide (NOx) emission and smoke emission are reduced by 3.3-3.9 and 5.1-6.4% for pentanol and biodiesel blends compared to neat biodiesel. Introduction of pentanol to biodiesel reduces the unburned hydrocarbon (2.1-3.6%) and carbon monoxide emissions (3.1-4.2%) considerably. In addition, at 20% EGR rate, smoke, NO X emissions, and BTE drop by 7.8, 5.1, and 4.4% respectively. However, CO, HC emissions, and BSFC increased by 2.1, 2.8, and 3.8%, respectively, when compared to 0% EGR rate.

  19. Gas Turbine/Solar Parabolic Trough Hybrid Design Using Molten Salt Heat Transfer Fluid: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C. S.; Ma, Z.

    2011-08-01

    Parabolic trough power plants can provide reliable power by incorporating either thermal energy storage (TES) or backup heat from fossil fuels. This paper describes a gas turbine / parabolic trough hybrid design that combines a solar contribution greater than 50% with gas heat rates that rival those of natural gas combined-cycle plants. Previous work illustrated benefits of integrating gas turbines with conventional oil heat-transfer-fluid (HTF) troughs running at 390?C. This work extends that analysis to examine the integration of gas turbines with salt-HTF troughs running at 450 degrees C and including TES. Using gas turbine waste heat to supplement the TES system provides greater operating flexibility while enhancing the efficiency of gas utilization. The analysis indicates that the hybrid plant design produces solar-derived electricity and gas-derived electricity at lower cost than either system operating alone.

  20. Heat transfer in a compact heat exchanger containing rectangular channels and using helium gas

    Science.gov (United States)

    Olson, D. A.

    1991-01-01

    Development of a National Aerospace Plane (NASP), which will fly at hypersonic speeds, require novel cooling techniques to manage the anticipated high heat fluxes on various components. A compact heat exchanger was constructed consisting of 12 parallel, rectangular channels in a flat piece of commercially pure nickel. The channel specimen was radiatively heated on the top side at heat fluxes of up to 77 W/sq cm, insulated on the back side, and cooled with helium gas flowing in the channels at 3.5 to 7.0 MPa and Reynolds numbers of 1400 to 28,000. The measured friction factor was lower than that of the accepted correlation for fully developed turbulent flow, although the uncertainty was high due to uncertainty in the channel height and a high ratio of dynamic pressure to pressure drop. The measured Nusselt number, when modified to account for differences in fluid properties between the wall and the cooling fluid, agreed with past correlations for fully developed turbulent flow in channels. Flow nonuniformity from channel-to-channel was as high as 12 pct above and 19 pct below the mean flow.

  1. Controlling exhaust gas recirculation

    Science.gov (United States)

    Zurlo, James Richard [Madison, WI; Konkle, Kevin Paul [West Bend, WI; May, Andrew [Milwaukee, WI

    2012-01-31

    In controlling an engine, an amount of an intake charge provided, during operation of the engine, to a combustion chamber of the engine is determined. The intake charge includes an air component, a fuel component and a diluent component. An amount of the air component of the intake charge is determined. An amount of the diluent component of the intake charge is determined utilizing the amount of the intake charge, the amount of the air component and, in some instances, the amount of the fuel component. An amount of a diluent supplied to the intake charge is adjusted based at least in part on the determined amount of diluent component of the intake charge.

  2. Arc-heated gas flow experiments for hypersonic propulsion applications

    Science.gov (United States)

    Roseberry, Christopher Matthew

    Although hydrogen is an attractive fuel for a hypersonic air-breathing vehicle in terms of reaction rate, flame temperature, and energy content per unit mass, the substantial tank volume required to store hydrogen imposes a drag penalty to performance that tends to offset these advantages. An alternative approach is to carry a hydrocarbon fuel and convert it on-board into a hydrogen-rich gas mixture to be injected into the engine combustors. To investigate this approach, the UTA Arc-Heated Wind Tunnel facility was modified to run on methane rather than the normally used nitrogen. Previously, this facility was extensively developed for the purpose of eventually performing experiments simulating scramjet engine flow along a single expansion ramp nozzle (SERN) in addition to more generalized applications. This formidable development process, which involved modifications to every existing subsystem along with the incorporation of new subsystems, is described in detail. Fortunately, only a minor plumbing reconfiguration was required to prepare the facility for the fuel reformation research. After a failure of the arc heater power supply, a 5.6 kW plasma-cutting torch was modified in order to continue the arc pyrolysis experiments. The outlet gas flow from the plasma torch was sampled and subsequently analyzed using gas chromatography. The experimental apparatus converted the methane feedstock almost completely into carbon, hydrogen and acetylene. A high yield of hydrogen, consisting of a product mole fraction of roughly 0.7, was consistently obtained. Unfortunately, the energy consumption of the apparatus was too excessive to be feasible for a flight vehicle. However, other researchers have pyrolyzed hydrocarbons using electric arcs with much less power input per unit mass.

  3. Energy analysis of technological systems of natural gas fired combined heat-and-power plants

    Energy Technology Data Exchange (ETDEWEB)

    Zaporowski, B.; Szczerbowski, R. [Poznan University of Technology (Poland)

    2003-06-01

    In this paper, multivariant simulation calculations are performed for the following natural-gas fired combined heat-and-power plants with gas turbines: (1) a gas-steam combined heat-and-power plant with an extraction-condensing steam turbine, and (2) a gas-steam combined heat-and-power plant with a back-pressure steam-turbine. For these systems, mathematical models of the behaviours of their basic elements, such as : the block of the gas turbine (compressor, combustion chamber and gas turbine), heat-recovery steam generator and steam-turbine cycle were developed. On the basis of elaborate mathematical models, a computer program performed multivariant simulation calculations. For each variant, the following factors were calculated for particular types of combined heat-and-power plants: energy efficiency, efficiency of electric-energy generation, cogeneration index and cogeneration factor. (author)

  4. Integration of bio-fired gas turbines in combined heat and power generation; Integrering av biogaseldad gasturbin i kraftvaermeanlaeggning

    Energy Technology Data Exchange (ETDEWEB)

    Genrup, Magnus; Jonshagen, Klas

    2011-01-15

    The aim of the project was to perform a pre-study of the potential to introduce a biofired gas turbine into the pre-heater train of a district heating plant. The incentive for the work is the desire (and political drivers) to increase bio-fuel usage in heat and power production. Sweden has also ratified the EU treaty of having 20 percent renewable in the system before 2020. There are several options at the hand but locally produced biofuels from either gasification or biological processes can be fired in a gas turbine. The size of the gas turbine is limited by shear size of the fuel plant and raw-material transport issues. Today, the maximum electrical efficiency for large-scale advanced plants is on the order of 60 percent. This level is, however, not feasible for smaller size units and one can expect much lower levels. Another possibility is to re-power an existing plant and use the exhaust heat from the gas turbine. Either to produce steam in a heat recovery steam generator, heat boiler combustion air (and variants) or to reduce pre-heater extraction through by-passing the pre-heaters. Previous studies have shown that one could expect very high efficiency levels if the heat could be utilized in the feed water to the boiler. This is typically coupled to the admission pressure level and super-critical plant may have feed water temperature exceeding 300 deg C. The aim of this project was to investigate the potential from introducing this technology into a certain typical Swedish/Nordic turbine based district heating plant. A typical plant has modest admission data (compared to an ultra super-critical plant), hence lower final feed water temperature. A lower final temperature makes it more troublesome to effectively use the exhaust heat from the gas turbine. A further improvement is possible by introducing reheat. There are several practical limitations, where the most severe is the need to extract the full turbine flow and induce it after the reheater. The only

  5. Use of natural gas, methanol, and ethanol fuel emulsions as environmentally friendly energy carriers for mobile heat power plants

    Science.gov (United States)

    Likhanov, V. A.; Lopatin, O. P.

    2017-12-01

    The need for using environmentally friendly energy carriers for mobile heat power plants (HPPs) is grounded. Ecologically friendly sources of energy, such as natural gas as well as renewable methyl and ethyl alcohols, are investigated. In order to develop, determine, and optimize the composition of environmentally friendly energy carriers for an HPP, the latter has been tested when working on diesel fuel (DF), compressed natural gas (CNG), and methanol and ethanol fuel emulsions (MFE, EFE). It has been experimentally established that, for the application of environmentally friendly energy carriers for a 4Ch 11.0/12.5 diesel engine of a mobile fuel and power plant, it is necessary to maintain the following ratio of components when working on CNG: 80% gas and 20% DF primer portion. When working on an alcohol mixture, emulsions of the following composition were used: 25% alcohol (methanol or ethanol), 0.5% detergent-dispersant additive succinimide C-5A, 7% water, and 67.5% DF. When this diesel passed from oil DF to environmentally friendly energy sources, it allowed for the reduction of the content of exhaust gases (EG) (1) when working on CNG with recirculation of exhaust gases (EGR) (recirculation was used to eliminate the increased amount of nitric oxides by using CNG): carbon black by 5.8 times, carbon dioxide by 45.9%, and carbon monoxide by 23.8%; (2) when working on MFE: carbon black by 6.4 times, nitrogen oxides by 29.6%, carbon dioxide by 10.1%, and carbon oxide by 47.6%; (3) when working on EFE: carbon black by 4.8 times; nitrogen oxides by 40.3%, carbon dioxide by 26.6%, and carbon monoxide by 28.6%. The prospects of use of environmentally friendly energy carriers in diesels of mobile HPPs, such as natural gas, ethanol, and methanol, has been determined.

  6. Evaporators for mobile waste heat recovery systems; Verdampfer zur Abwaermenutzung im Fahrzeug

    Energy Technology Data Exchange (ETDEWEB)

    Ambros, Peter; Fezer, Axel; Necker, Harald [Thesys GmbH, Kirchentellinsfurt (Germany); Orso,Jochen [Thesys GmbH, Kirchentellinsfurt (Germany); Hochschule Reutlingen (Germany)

    2011-01-15

    Thesys develops evaporators for waste heat recovery systems for mobile and stationary applications. These evaporators utilize the enthalpy availability of hot exhaust gas both in the cooled exhaust gas recirculation duct as well as in the main exhaust gas for example in the muffler. At present there are three different designs for evaporators under development. Prototype measurements have already partially proved their function and performance. (orig.)

  7. High-Speed Multiplexed Spatiotemporally Resolved Measurements of Exhaust Gas Recirculation Dynamics in a Multi-Cylinder Engine Using Laser Absorption Spectroscopy.

    Science.gov (United States)

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

    2016-04-01

    The need for more environmentally friendly and efficient energy conversion is of paramount importance in developing and designing next-generation internal combustion (IC) engines for transportation applications. One effective solution to reducing emissions of mono-nitrogen oxides (NOx) is exhaust gas recirculation (EGR), which has been widely implemented in modern vehicles. However, cylinder-to-cylinder and cycle-to-cycle variations in the charge-gas uniformity can be a major barrier to optimum EGR implementation on multi-cylinder engines, and can limit performance, stability, and efficiency. Precise knowledge and fine control over the EGR system is therefore crucial, particularly for optimizing advanced engine concepts such as reactivity controlled compression ignition (RCCI). An absorption-based laser diagnostic was developed to study spatiotemporal charge-gas distributions in an IC engine intake manifold in real-time. The laser was tuned to an absorption band of carbon dioxide (CO2), a standard exhaust-gas marker, near 2.7 µm. The sensor was capable of probing four separate measurement locations simultaneously, and independently analyzing EGR fraction at speeds of 5 kHz (1.2 crank-angle degree (CAD) at 1 k RPM) or faster with high accuracy. The probes were used to study spatiotemporal EGR non-uniformities in the intake manifold and ultimately promote the development of more efficient and higher performance engines. © The Author(s) 2016.

  8. Principle Findings from Development of a Recirculated Exhaust Gas Intake Sensor (REGIS) Enabling Cost-Effective Fuel Efficiency Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Schnabel, Claus [Robert Bosch LLC, Farmington Hills, MI (United States)

    2016-03-30

    Kick-off of the Bosch scope of work for the REGIS project started in October 2012. The primary work-packages included in the Bosch scope of work were the following: overall project management, development of the EGR sensor (design of sensor element, design of protection tube, and design of mounting orientation), development of EGR system control strategy, build-up of prototype sensors, evaluation of system performance with the new sensor and the new control strategy, long-term durability testing, and development of a 2nd generation sensor concept for continued technology development after the REGIS project. The University of Clemson was a partner with Bosch in the REGIS project. The Clemson scope of work for the REGIS project started in June 2013. The primary work-packages included in the Clemson scope of work were the following: development of EGR system control strategy, and evaluation of system performance with the new sensor and new control strategy. This project was split into phase I, phase II and phase III. Phase I work was completed by the end of June 2014 and included the following primary work packages: development of sensor technical requirements, assembly of engine testbench at Clemson, design concept for sensor housing, connector, and mounting orientation, build-up of EGR flow test benches at Bosch, and build-up of first sensor prototypes. Phase II work was completed by the end of June 2015 and included the following primary work pack ages: development of an optimizing function and demonstration of robustness of sensor, system control strategy implementation and initial validation, completion of engine in the loop testing of developed control algorithm, completion of sensor testing including characteristic line, synthetic gas test stand, and pressure dependency characterization, demonstration of benefits of control w/o sensing via simulation, development of 2nd generation sensor concept. Notable technical achievements from phase II were the following

  9. Black carbon from ships: a review of the effects of ship speed, fuel quality and exhaust gas scrubbing

    Directory of Open Access Journals (Sweden)

    D. A. Lack

    2012-05-01

    Full Text Available The International Maritime Organization (IMO has moved to address the health and climate impact of the emissions from the combustion of low-quality residual fuels within the commercial shipping industry. Fuel sulfur content (FS limits and an efficiency design index for future ships are examples of such IMO actions. The impacts of black carbon (BC emissions from shipping are now under review by the IMO, with a particular focus on the potential impacts of future Arctic shipping.

    Recognizing that associating impacts with BC emissions requires both ambient and onboard observations, we provide recommendations for the measurement of BC. We also evaluate current insights regarding the effect of ship speed (engine load, fuel quality and exhaust gas scrubbing on BC emissions from ships. Observations demonstrate that BC emission factors (EFBC increases 3 to 6 times at very low engine loads (<25% compared to EFBC at 85–100% load; absolute BC emissions (per nautical mile of travel also increase up to 100% depending on engine load, even with reduced load fuel savings. If fleets were required to operate at lower maximum engine loads, presumably associated with reduced speeds, then engines could be re-tuned, which would reduce BC emissions.

    Ships operating in the Arctic are likely running at highly variable engine loads (25–100% depending on ice conditions and ice breaking requirements. The ships operating at low load may be emitting up to 50% more BC than they would at their rated load. Such variable load conditions make it difficult to assess the likely emissions rate of BC.

    Current fuel sulfur regulations have the effect of reducing EFBC by an average of 30% and potentially up to 80% regardless of engine load; a removal rate similar to that of scrubbers.

    Uncertainties among current observations demonstrate there is a need for more information on a the impact of fuel quality

  10. Residential gas-fired sorption heat pumps. Test and technology evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Naeslund, M.

    2008-12-15

    Heat pumps may be the next step in gas-fired residential space heating. Together with solar energy it is an option to combine natural gas and renewable energy. Heat pumps for residential space heating are likely to be based on the absorption or adsorption process, i.e. sorption heat pumps. Manufacturers claim that the efficiency could reach 140-160%. The annual efficiency will be lower but it is clear that gas-fired heat pumps can involve an efficiency and technology step equal to the transition from non-condensing gas boilers with atmospheric burners to condensing boilers. This report contains a review of the current sorption gas-fired heat pumps for residential space heating and also the visible development trends. A prototype heat pump has been laboratory tested. Field test results from Germany and the Netherlands are also used for a technology evaluation. The tested heat pump unit combines a small heat pump and a supplementary condensing gas boiler. Field tests show an average annual efficiency of 120% for this prototype design. The manufacturer abandoned the tested design during the project period and the current development concentrates on a heat pump design only comprising the heat pump, although larger. The heat pump development at three manufacturers in Germany indicates a commercial stage around 2010-2011. A fairly high electricity consumption compared to traditional condensing boilers was observed in the tested heat pump. Based on current prices for natural gas and electricity the cost savings were estimated to 12% and 27% for heat pumps with 120% and 150% annual efficiency respectively. There is currently no widespread performance testing procedure useful for annual efficiency calculations of gas-fired heat pumps. The situation seems to be clearer for electric compression heat pumps regarding proposed testing and calculation procedures. A German environmental label exists and gasfired sorption heat pumps are also slightly treated in the Eco-design work

  11. IDENTIFICATION OF SOME CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS IN BANGLADESHI VEHICLES EXHAUST TAR BY GAS CHROMATOGRAPHY-MASS SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    M. Amzad Hossain

    2010-06-01

    Full Text Available A more sensitive GC-MS method has been established for the determination of some carcinogenic polycyclic aromatic hydrocarbons (PAHs in vehicles exhaust tar samples. The tar samples were extracted using dichloromethane (DMC: n-hexane solvent mixture. A multi-layer clean-up (silica gel/sodium sulphate column was used, followed by glass fiber filter (GFF paper. The method was successfully applied to determine a number of PAHs present in exhaust tar sample of different vehicles of the Atomic Energy Centre, Dhaka, Bangladesh.   Keywords: Carcinogenic polycyclic aromatic hydrocarbons, vehicles tar samples, identification, GC-MS/MS

  12. Fast Gas-gap heat switch for a microcooler

    NARCIS (Netherlands)

    Burger, Johannes Faas; Holland, Herman J.; Elwenspoek, Michael Curt; ter Brake, Hermanus J.M.; Rogalla, Horst; van Egmond, H.J.

    1999-01-01

    A sorption compressor requires heat switches to thermally isolate the cells during heating, and to connect them to a heat sink during cooling. The requirements for these heat switches are discussed and related to important compressor parameters. It is shown that under certain conditions a sorption

  13. Temperature patterns in the gas infrared radiator heating area

    Directory of Open Access Journals (Sweden)

    Kurilenko N.I.

    2015-01-01

    Full Text Available The obtained results of experimental studies provide the basis for the heat transfer mechanism specification on the studied conditions that are typical for many practical applications. It was proved appropriateness of the natural convection and heat conduction process simulation while analyzing the heat transfer in rectangular enclosures with the radiant heating sources at the high bound.

  14. Simplified prediction of soot emissions in the exhaust of gas turbines operated at atmospheric pressure; Prediction simplifiee des emissions de suie a la sortie des chambres de combustion des turbines a gaz operees a la pression atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Tsogo, J. [College de la garde cotiere du Canada, Departement de genie maritime, Sydney (Canada); Kretschmer, D. [Universite Laval, Departement de genie mecanique, Quebec (Canada)

    2010-04-15

    In previous works [1, 2], a correlation for the prediction of soot in gas turbine exhaust has been presented. The development of the correlation is based on 300 of experimental data for a total of 19 fuels burned both at atmospheric and high pressure (0.1 to 0.9 MPa) and two scales (1/2 and 1/3) of a Laval type combustion chamber. With the wide range of fuels burned in the experiment giving a smoke number variation from 0 to 100, the accuracy of the correlation (Standard Deviation of 40%) is acceptable for most purposes Later on the correlation has been improved using data from the full scaled combustion chamber as shown in [3]. A detailed analysis of the correlation is undertaken within the present work for the case of the experiments at atmospheric pressure. The result is a simplification of the correlation presented in [3] without a major deterioration of the standard deviation. This result leads to a simplification of the previous proposed soot formation and oxidation model within gas turbine combustors (operated at atmospheric pressure) and limits the analysis of the phenomenon on essential functional parameters as well. Gas turbines are generally used in aircraft, ships, and in stationary production of electricity, heat and vapor. (author)

  15. Application of Evaporative Cooling for the Condensation of Water Vapors from a Flue Gas Waste Heat Boilers CCP

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2016-01-01

    Full Text Available The object of the study are boilers that burn organic fuel and the recovery boilers (RB of the combined cycle plant (CCP, which are al-so working on the products of the combustion of hydrocarbon fuels. The purpose of research is to find technologies that increase efficiency of the thermal power plant (TPP and technologies that reduce the environmental impact on the environment by burning fossil fuels. The paper deals with the technology of the boilers burning hydrocarbon fuel with condensation of water vapor from the exhaust flue gases. Considered the problems caused by using of this technology. Research shows that the main problem of this technology in the boilers is the lack of reliable methods of calculation of heat exchangers, condensers. Particular attention is paid to the application of this technology in the recovery boilers combined-cycle plants, which are currently gaining increasing use in the generation of electricity from the combustion of gas in power plants. It is shown that the application of technology of condensation of water vapor in RB CCP, the temperature decreases of exhaust gases from 100 to 40 °С, allows increasing the effi-ciency of the RB with 86.2 % to 99.5 %, i.e. at 12.3 %, and increase the ef-ficiency of the CCP at 2.8 %.

  16. Optimization of Heat Exchangers for Intercooled Recuperated Aero Engines

    National Research Council Canada - National Science Library

    Dimitrios Misirlis; Zinon Vlahostergios; Michael Flouros; Christina Salpingidou; Stefan Donnerhack; Apostolos Goulas; Kyros Yakinthos

    2017-01-01

    .... The present work is focused only on the recuperation process. This is carried out through a system of heat exchangers mounted inside the hot-gas exhaust nozzle, providing fuel economy and reduced pollutant emissions...

  17. Assessment of solar-assisted gas-fired heat pump systems

    Science.gov (United States)

    Lansing, F. L.

    1981-01-01

    As a possible application for the Goldstone Energy Project, the performance of a 10 ton heat pump unit using a hybrid solar gas energy source was evaluated in an effort to optimize the solar collector size. The heat pump system is designed to provide all the cooling and/or heating requirements of a selected office building. The system performance is to be augmented in the heating mode by utilizing the waste heat from the power cycle. A simplified system analysis is described to assess and compute interrrelationships of the engine, heat pump, and solar and building performance parameters, and to optimize the solar concentrator/building area ratio for a minimum total system cost. In addition, four alternative heating cooling systems, commonly used for building comfort, are described; their costs are compared, and are found to be less competitive with the gas solar heat pump system at the projected solar equipment costs.

  18. Improving the Efficiency of the Heat Pump Control System of Carbon Dioxide Heat Pump with Several Evaporators and Gas Coolers

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2016-12-01

    Full Text Available The problem of coordination of the values of the refrigerant flow through the evaporators and gas coolers of the heat pump for the simultaneous production of heat and cold is studied. The compensation of the variations of the total flow through the evaporators is implemented using the variation of the capacity of the compressor and a corresponding change in flow through the auxiliary gas cooler of the heat pump. Control system of this gas cooler is constructed using the invariance principle of the output value (outlet temperature of the heated agent with respect to perturbations on the control channel (the refrigerant flow through the gas cooler. Principle of dual-channel compensation of the disturbance and advancing signal on input of control valve of the refrigerant through the gas cooler is ensured. Due to proposed solution, the intensity of the disturbances on the flow of refrigerant is reduced. Due to proposed technical solution power consumed by the heat pump compressor drive under transients is decreased.

  19. Heat Exchange and Fouling Analysis on a Set of Hydrogen Sulphide Gas Coolers

    Directory of Open Access Journals (Sweden)

    Andrés Adrian Sánchez-Escalona

    2017-07-01

    Full Text Available The sulphide acid coolers are tube and shell jacketed heat exchangers designed to cool down the produced gas from 416,15 K to 310,15 K in addition to separate the sulphur carried over by the outlet gas from the reactor tower. The investigation was carried out by applying the passive experimentation process in an online cooler set in order to determine the heat transfer rates and fouling based on heat resistance. It was corroborated that the operation of this equipment outside design parameters increases outlet gas temperature and liquid sulphur carryovers. Efficiency loss is caused by fouling elements in the fluid, which results in changes in the overall heat transfer rate. The linear tendency of the fouling heat resistance based on time for three gas flowrates.

  20. Prototype Vent Gas Heat Exchanger for Exploration EVA - Performance and Manufacturing Characteristics

    Science.gov (United States)

    Quinn, Gregory J.; Strange, Jeremy; Jennings, Mallory

    2013-01-01

    NASA is developing new portable life support system (PLSS) technologies, which it is demonstrating in an unmanned ground based prototype unit called PLSS 2.0. One set of technologies within the PLSS provides suitable ventilation to an astronaut while on an EVA. A new component within the ventilation gas loop is a liquid-to-gas heat exchanger to transfer excess heat from the gas to the thermal control system s liquid coolant loop. A unique bench top prototype heat exchanger was built and tested for use in PLSS 2.0. The heat exchanger was designed as a counter-flow, compact plate fin type using stainless steel. Its design was based on previous compact heat exchangers manufactured by United Technologies Aerospace Systems (UTAS), but was half the size of any previous heat exchanger model and one third the size of previous liquid-to-gas heat exchangers. The prototype heat exchanger was less than 40 cubic inches and weighed 2.57 lb. Performance of the heat exchanger met the requirements and the model predictions. The water side and gas side pressure drops were less 0.8 psid and 0.5 inches of water, respectively, and an effectiveness of 94% was measured at the nominal air side pressure of 4.1 psia.

  1. Performance improvement of air source heat pump by using gas-injected rotary compressor

    Science.gov (United States)

    Wang, B. L.; Liu, X. R.; Ding, Y. C.; Shi, W. X.

    2017-08-01

    Rotary compressor is most widely used in small capacity refrigeration and heat pump systems. For the air source heat pump, the heating capacity and the COP will be obviously degraded when it is utilized in low temperature ambient. Gas injection is an effective method to enhance its performance under those situations, which has been well applied in air source heat pump with scroll compressor. However, the development of the gas injection technology in rotary compressor is relatively slow due to limited performance improvement. In this research, the essential reason constraining the improvement of the gas injection on the rotary compressor and its heat pump system is identified. Two new injection structures for rotary compressors has been put forward to overcome the drawback of traditional injection structures. Based on a verified numerical model, the thermodynamic performance of air source heat pumps with the new gas-injected rotary compressor are investigated. The results indicate that, compared to the air source heat pump with the traditional gas injected rotary compressor, the new injection structures both can enhance heating capacity and COP of the air source heat pump obviously.

  2. High effectiveness liquid droplet/gas heat exchanger for space power applications

    Science.gov (United States)

    Bruckner, A. P.; Mattick, A. T.

    1983-01-01

    A high-effectiveness liquid droplet/gas heat exchanger (LDHX) concept for thermal management in space is described. Heat is transferred by direct contact between fine droplets (approximately 100-300 microns in diameter) of a suitable low vapor pressure liquid and an inert working gas. Complete separation of the droplet and gas media in the zero-g environment is accomplished by configuring the LDHX as a vortex chamber.The large heat transfer area presented by the small droplets permits heat exchanger effectiveness of 0.9-0.95 in a compact, lightweight geometry which avoids many of the limitations of conventional plate and fin or tube and shell heat exchangers, such as their tendency toward single point failure. The application of the LDHX in a high temperature Brayton cycle is discussed to illustrate the performance and operational characteristics of this new heat exchanger concept.

  3. Heat Transfer and Pressure Drop in Concentric Annular Flows of Binary Inert Gas Mixtures

    Science.gov (United States)

    Reid, R. S.; Martin, J. J.; Yocum, D. J.; Stewart, E. T.

    2007-01-01

    Studies of heat transfer and pressure drop of binary inert gas mixtures flowing through smooth concentric circular annuli, tubes with fully developed velocity profiles, and constant heating rate are described. There is a general lack of agreement among the constant property heat transfer correlations for such mixtures. No inert gas mixture data exist for annular channels. The intent of this study was to develop highly accurate and benchmarked pressure drop and heat transfer correlations that can be used to size heat exchangers and cores for direct gas Brayton nuclear power plants. The inside surface of the annular channel is heated while the outer surface of the channel is insulated. Annulus ratios range 0.5 spacer ribs, or other surfaces.

  4. 3. Future-oriented forum on gas heating; 3. Zukunftsforum ''Gasheizung''

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Within the future-oriented forum gas heating of the GWI Gaswaerme Institute e.V. (Essen, Federal Republic of Germany) between 07th and 08th June, 2011, at Henrichshuette (Hattingen, Federal Republic of Germany), the following lectures were held: (1) Change of paradigm in the energy economy - and the perspectives of gas economy?; (2) Energy political framework; (3) Technical innovation offensive for the development of future gas markets; (4) Development of the German heating market; (5) Natural gas: The bridge to the regenerative aera; (6) Key technologies in the utilization of gas, (7) InnovationCity Ruhr - Idea.Concept.Strategy; (8) Panel discussion with referents of the meeting: Scenarios of future structures of energy supply; (9) Heating market 2020 - Looking into the future; (10) Market analysis on criteria of decision and motives of the final customers; (11) Presentation of actual gas technologies - Recapitulation to ISH 2011; (12) Practical experiences in the hydrogen production and methanization.

  5. Investigation of the Performance of HEMT-Based NO, NO2 and NH3 Exhaust Gas Sensors for Automotive Antipollution Systems

    Directory of Open Access Journals (Sweden)

    Yacine Halfaya

    2016-02-01

    Full Text Available We report improved sensitivity to NO, NO2 and NH3 gas with specially-designed AlGaN/GaN high electron mobility transistors (HEMT that are suitable for operation in the harsh environment of diesel exhaust systems. The gate of the HEMT device is functionalized using a Pt catalyst for gas detection. We found that the performance of the sensors is enhanced at a temperature of 600 °C, and the measured sensitivity to 900 ppm-NO, 900 ppm-NO 2 and 15 ppm-NH 3 is 24%, 38.5% and 33%, respectively, at 600 °C. We also report dynamic response times as fast as 1 s for these three gases. Together, these results indicate that HEMT sensors could be used in a harsh environment with the ability to control an anti-pollution system in real time.

  6. Investigation of the Performance of HEMT-Based NO, NO2 and NH3 Exhaust Gas Sensors for Automotive Antipollution Systems

    Science.gov (United States)

    Halfaya, Yacine; Bishop, Chris; Soltani, Ali; Sundaram, Suresh; Aubry, Vincent; Voss, Paul L.; Salvestrini, Jean-Paul; Ougazzaden, Abdallah

    2016-01-01

    We report improved sensitivity to NO, NO2 and NH3 gas with specially-designed AlGaN/GaN high electron mobility transistors (HEMT) that are suitable for operation in the harsh environment of diesel exhaust systems. The gate of the HEMT device is functionalized using a Pt catalyst for gas detection. We found that the performance of the sensors is enhanced at a temperature of 600 °C, and the measured sensitivity to 900 ppm-NO, 900 ppm-NO2 and 15 ppm-NH3 is 24%, 38.5% and 33%, respectively, at 600 °C. We also report dynamic response times as fast as 1 s for these three gases. Together, these results indicate that HEMT sensors could be used in a harsh environment with the ability to control an anti-pollution system in real time. PMID:26907298

  7. Calculation and Designing of Up-to-Date Gas-Flame Plants for Metal Heating and Heat Treatment

    Directory of Open Access Journals (Sweden)

    V. I. Тimoshpolsky

    2008-01-01

    Full Text Available An analysis of development trends in the CIS machine-building industry and current status of the heating and heat treatment furnaces of main machine-building enterprises of the Republic of Belarus as of the 1st quarter of 2008 is given in the paper.The paper presents the most efficient engineering solutions from technological and economic point of view that concern calculation and designing of up-to-date gas-flame plants which are to be applied for modernization of the current heating and heat treatment furnaces of the machine-building enterprises in the Republic of Belarus.A thermo-technical calculation of main indices of the up-to-date gas-flame plant has been carried out in the paper.

  8. Exhaust gas emission from two-stroke engines in private cars and motorcycles in West Germany. Abgasemissionen von Zweitaktmotoren in Personenkraftwagen und Motorraedern der Bundesrepublik Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, C. (Rheinisch-Westfaelischer Technischer Ueberwachungs-Verein e.V., Essen (Germany, F.R.). Inst. fuer Fahrzeugtechnik)

    1990-01-01

    The proportion of motorised cycles is only about 10% of the stock of cars in West Germany, but their harmful emission are not negligible, as these two-wheeled vehicles are mainly driven in towns or near towns. The emission of carbon monoxide, hydrocarbons and nitrogen oxides and also of particle-bound, polycyclic, aromatic hydrocarbons was therefore determined in the driving cycle and at constant speeds. The results obtained can be seen from many diagrams. Some measures to reduce the emission of harmful substances were tried on a series of 2-stroke engines (250 cc). These included postcombustion, oxidation catalyst, blowing in additional air, manually controlled additional carburettor or a combination of these measures. From our present state of knowledge, a simple 2-stroke engine cannot comply with the requirements regarding exhaust gas emission behaviour and fuel consumption. Such a 2-stroke engine will in future have to have direct, electronically controlled injection and probably a combined slot and valve controlled common flow flushing, together with a catalytic exhaust gas treatment system. (orig.).

  9. Annual cycle solar energy utilization with seasonal storage. Part 7. Examination on design and control of the system partially recovering exhaust heat of heat pump; Kisetsukan chikunetsu ni yoru nenkan cycle taiyo energy riyo system ni kansuru kenkyu. 7. Bubuntekina hainetsu kaishu wo koryoshita baai no sekkei seigyoho no kento

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H.; Okumiya, M. [Nagoya University, Nagoya (Japan)

    1996-10-27

    The capacity and performance of the existing system that recovers the overall heating and cooling exhaust heat completely into a seasonal storage tank and the system that discharges the exhaust heat slightly to the outside and recovers it partially were compared and investigated. The system uses a central single-duct discharge system as an air-conditioning system. A heat pump and a flat-plate solar collector installed on the roof of a building are used as the heat source. The seasonal storage tank in the ground just under the building is a cylindrical water tank of 5 m deep with the concrete used as body. The upper surface of a storage tank is heat-insulated by a stylo-platform of 200 mm, and the lower side surface by a stylo-platform of 100 mm. Calculation when the difference in temperature used in a seasonal storage tank is set to 35{degree}C and 25{degree}C was performed for the system that has two control methods. The overall exhaust heat recovery system is almost the same in energy performance as the partial exhaust heat recovery system. The partial exhaust heat recovery system is more advantageous on the economic side. 4 refs., 6 figs., 3 tabs.

  10. Heating and cooling system for an on-board gas adsorbent storage vessel

    Energy Technology Data Exchange (ETDEWEB)

    Tamburello, David A.; Anton, Donald L.; Hardy, Bruce J.; Corgnale, Claudio

    2017-06-20

    In one aspect, a system for controlling the temperature within a gas adsorbent storage vessel of a vehicle may include an air conditioning system forming a continuous flow loop of heat exchange fluid that is cycled between a heated flow and a cooled flow. The system may also include at least one fluid by-pass line extending at least partially within the gas adsorbent storage vessel. The fluid by-pass line(s) may be configured to receive a by-pass flow including at least a portion of the heated flow or the cooled flow of the heat exchange fluid at one or more input locations and expel the by-pass flow back into the continuous flow loop at one or more output locations, wherein the by-pass flow is directed through the gas adsorbent storage vessel via the by-pass line(s) so as to adjust an internal temperature within the gas adsorbent storage vessel.

  11. Radiating heat transfer in the power boiler downtake gas duct when firing high-ash coal

    Energy Technology Data Exchange (ETDEWEB)

    Sudarev, A.V.; Antonovsky, V.I.; Kiselev, O.V.; Sivchikov, S.B. (VTUS-Leningrad Metal Plant-LMZ, Leningrad (USSR))

    1990-01-01

    The experimental study of radiation heat transfer in the downtake gas duct of the pulverized-coal fired steam boiler for 500 MW power unit when firing high-ash (40% ash content) coal from Ekibastuz coal field was carried out by means of the radiometer probe with rotary optical axis. The local values of the combustion product temperature were measured simultaneously in the down-take and the operation parameters for boiler gas and steam ducts were registered. The dependence of the extinction coefficient of combustion products on the radiating layer thickness was obtained. The radiating power, generated in the gas space, remote from the steam superheater and reaching the super heater boundaries, was measured. The heat release coefficients from radiation and heat transfer coefficients, were determined for definite operation conditions of the superheater working. The contribution of the gas space outside the steam superheater into the radiating heat transfer negligible.

  12. Influence of heat exchange of reservoir with rocks on hot gas injection via a single well

    Science.gov (United States)

    Nikolaev, Vladimir E.; Ivanov, Gavril I.

    2017-11-01

    In the computational experiment the influence of heat exchange through top and bottom of the gas-bearing reservoir on the dynamics of temperature and pressure fields during hot gas injection via a single well is investigated. The experiment was carried out within the framework of modified mathematical model of non-isothermal real gas filtration, obtained from the energy and mass conservation laws and the Darcy law. The physical and caloric equations of state together with the Newton-Riemann law of heat exchange of gas reservoir with surrounding rocks, are used as closing relations. It is shown that the influence of the heat exchange with environment on temperature field of the gas-bearing reservoir is localized in a narrow zone near its top and bottom, though the size of this zone is increased with time.

  13. A Passive, Adaptive and Autonomous Gas Gap Heat Switch

    NARCIS (Netherlands)

    Vanapalli, Srinivas; Colijn, B.A.; Vermeer, Cristian Hendrik; Holland, Herman J.; Tirolien, T.; ter Brake, Hermanus J.M.

    2015-01-01

    We report on the development of a heat switch for autonomous temperature control of electronic components in a satellite. A heat switch can modulate when needed between roles of a good thermal conductor and a good thermal insulator. Electronic boxes on a satellite should be maintained within a

  14. CFD as a Design Tool for a Concentric Heat Exchanger

    NARCIS (Netherlands)

    Oosterhuis, Joris; Bühler, Simon; wilcox, D; van der Meer, Theodorus H.

    2012-01-01

    A concentric gas-to-gas heat exchanger is designed for application as a recuperator in the domestic boiler industry. The recuperator recovers heat from the exhaust gases of a combustion process to preheat the ingoing gaseous fuel mixture resulting in increased fuel efficiency. This applied study

  15. Icing Characteristics and Anti-Icing Heat Requirements for Hollow and Ternally Modified Gas-Heated Inlet Guide Vanes

    Science.gov (United States)

    Gray, Vernon H.; Bowden, Dean T.

    1950-01-01

    A two-dimensional inlet-guide-vane cascade was investigated to determine the effects of ice formations on the pressure losses across the guide vanes and to evaluate the heated gas flow and temperature required to prevent Icing at various conditions. A gas flow of approximately 0.4 percent of the inlet-air flow was necessary for anti-icing a hollow guide-vane stage at an inlet-gas temperature of 500 F under the following icing conditions: air velocity, 280 miles per hour; water content, 0.9 gram per cubic meter; and Inlet-air static temperature, 00 F. Also presented are the anti-icing gas flows required with modifications of the hollow Internal gas passage, which show heatinput savings greater than 50 percent.

  16. Dynamics of heat, water, and soluble gas exchange in the human airways: 1. A model study.

    Science.gov (United States)

    Tsu, M E; Babb, A L; Ralph, D D; Hlastala, M P

    1988-01-01

    In order to provide a means for analysis of heat, water, and soluble gas exchange with the airways during tidal ventilation, a one dimensional theoretical model describing heat and water exchange in the respiratory airways has been extended to include soluble gas exchange with the airway mucosa and water exchange with the mucous layer lining the airways. Not only do heat, water, and gas exchange occur simultaneously, but they also interact. Heating and cooling of the airway surface and mucous lining affects both evaporative water and soluble gas exchange. Water evaporation provides a major source of heat exchange. The model-predicted mean airway temperature profiles agree well with literature data for both oral and nasal breathing validating that part of the model. With model parameters giving the best fit to experimental data, the model shows: (a) substantial heat recovery in the upper airways, (b) minimal respiratory heat and water loss, and (c) low average mucous temperatures and maximal increases in mucous thickness. For resting breathing of room air, heat and water conservation appear to be more important than conditioning efficiency. End-tidal expired partial pressures of very soluble gases eliminated by the lungs are predicted to be lower than the alveolar partial pressures due to the absorption of the expired gases by the airway mucosa. The model may be usable for design of experiments to examine mechanisms associated with the local hydration and dehydration dynamics of the mucosal surface, control of bronchial perfusion, triggering of asthma, mucociliary clearance and deposition of inhaled pollutant gases.

  17. 46 CFR 61.15-10 - Liquefied-petroleum-gas piping for heating and cooking.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Liquefied-petroleum-gas piping for heating and cooking. 61.15-10 Section 61.15-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PERIODIC TESTS AND INSPECTIONS Periodic Tests of Piping Systems § 61.15-10 Liquefied-petroleum-gas...

  18. Determination of the Specific Heat Ratio of a Gas in a Plastic Syringe

    Science.gov (United States)

    Chamberlain, Jeff

    2010-01-01

    The rapid compression or expansion of a gas in a plastic syringe is a poor approximation of an adiabatic process. Heat exchange with the walls of the syringe brings the gas to equilibrium in an amount of time that is not significantly greater than the length of the compression or expansion itself. Despite this limitation, it is still possible to…

  19. Conversion of individual natural gas to district heating

    DEFF Research Database (Denmark)

    Möller, Bernd; Lund, Henrik

    2010-01-01

    location relative to energy infrastructure. First, using a spatially explicit economic model, the study calculates the potentials and costs of connection to expanded district heating networks by supply technology. Then a comprehensive energy systems analysis is carried out to model how the new district....... The analyses suggest to expand district heating from present 46% to somewhere in between 50% and 70%. The most attractive potential is located around towns and cities. The study also suggests that CO2-emissions, fuel consumption and socioeconomic costs can be reduced by expanding district heating, while...

  20. Design and Development of a Residential Gas-Fired Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Vineyard, Edward Allan [ORNL; Abu-Heiba, Ahmad [ORNL; Mahderekal, Dr. Isaac [Intellichoice Energy, Boulder City, Nevada

    2017-01-01

    Heating, ventilating, and air-conditioning equipment consumes 43% of the total primary energy consumption in U.S. households. Presently, conventional gas furnaces have maximum heating efficiencies of 98%. Electric air conditioners used in association with the furnace for cooling have a minimum seasonal energy efficiency ratio (SEER) of 14.0. A residential gas-fired heat pump (RGHP) was developed and tested under standard rating conditions, resulting in a significant increase in heating efficiency of over 40% versus conventional natural gas furnaces. The associated efficiency of the RGHP in cooling mode is comparable in efficiency to an electric air conditioner (14.0 SEER) when compared on a primary energy basis. The RGHP is similar in nature to a conventional heat pump but with two main differences. First, the primary energy savings are higher, based on a site versus source comparison, as the result of using natural gas to supply shaft power to the compressor rather than an electric motor. Second, waste heat is recovered from the engine to supplement space heating and reduce the energy input. It can also be used to provide supplemental water heating. The system utilizes a programmable logic controller that allows variable-speed operation to achieve improved control to meet building loads. RGHPs significantly reduce peak electric use during periods of high demand, especially peak summer loads, as well as peak winter loads in regions with widespread use of electric heating. This contributes to leveling year-round gas loads, with the potential to increase annual gas demand in some regions. The widespread adoption of RGHPs will contribute to significant reductions in primary energy consumption and carbon emissions through improved efficiencies.

  1. Frozen heat: Global outlook on methane gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Beaudoin, Yannick; Solgaard, Anne

    2010-09-15

    The United Nations Environment Programme via its collaborating center in Norway, UNEP/GRID-Arendal, is undertaking an assessment of the state of the knowledge of methane gas hydrates. The Global Outlook on Methane Gas Hydrates seeks to bridge the gap between the science, research and development activities related to this potential large scale unconventional source of natural gas and the needs of decision makers and the general public to understand the underlying societal and environmental drivers and impacts. The Outlook aims to provide credible and unbiased information sourced from stakeholders representing the environment, government, industry and society.

  2. Development and Validation of a Gas-Fired Residential Heat Pump Water Heater - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Michael Garrabrant; Roger Stout; Paul Glanville; Janice Fitzgerald; Chris Keinath

    2013-01-21

    For gas-fired residential water heating, the U.S. and Canada is predominantly supplied by minimum efficiency storage water heaters with Energy Factors (EF) in the range of 0.59 to 0.62. Higher efficiency and higher cost ($700 - $2,000) options serve about 15% of the market, but still have EFs below 1.0, ranging from 0.65 to 0.95. To develop a new class of water heating products that exceeds the traditional limit of thermal efficiency, the project team designed and demonstrated a packaged water heater driven by a gas-fired ammonia-water absorption heat pump. This gas-fired heat pump water heater can achieve EFs of 1.3 or higher, at a consumer cost of $2,000 or less. Led by Stone Mountain Technologies Inc. (SMTI), with support from A.O. Smith, the Gas Technology Institute (GTI), and Georgia Tech, the cross-functional team completed research and development tasks including cycle modeling, breadboard evaluation of two cycles and two heat exchanger classes, heat pump/storage tank integration, compact solution pump development, combustion system specification, and evaluation of packaged prototype GHPWHs. The heat pump system extracts low grade heat from the ambient air and produces high grade heat suitable for heating water in a storage tank for domestic use. Product features that include conventional installation practices, standard footprint and reasonable economic payback, position the technology to gain significant market penetration, resulting in a large reduction of energy use and greenhouse gas emissions from domestic hot water production.

  3. Effects of a Dual-Loop Exhaust Gas Recirculation System and Variable Nozzle Turbine Control on the Operating Parameters of an Automotive Diesel Engine

    Directory of Open Access Journals (Sweden)

    Giorgio Zamboni

    2017-01-01

    Full Text Available Reduction of NOX emissions and fuel consumption are the main topics in engine development, forcing the adoption of complex techniques and components, whose interactions have to be clearly understood for proper and reliable operations and management of the whole system. The investigation presented in this paper aimed at the development of integrated control strategies of turbocharging, high pressure (HP and low pressure (LP exhaust gas recirculation (EGR systems for better NOX emissions and fuel consumption, while analyzing their reciprocal influence and the resulting variations of engine quantities. The study was based on an extended experimental program in three part load engine operating conditions. In the paper a comparison of the behavior of the main engine sub-systems (intake and exhaust circuits, turbocharger turbine and compressor, HP and LP EGR loops in a wide range of operating modes is presented and discussed, considering open and closed loop approaches for variable nozzle turbine (VNT control, and showing how these affect engine performance and emissions. The potential of significant decrease in NOX emissions through the integration of HP and LP EGR was confirmed, while a proper VNT management allowed for improved fuel consumption level, if an open loop control scheme is followed. At higher engine speed and load, further actions have to be applied to compensate for observed soot emissions increase.

  4. Passive Gas-Gap Heat Switches for Use in Low-Temperature Cryogenic Systems

    Science.gov (United States)

    Kimball, M. O.; Shirron, P. J.; Canavan, E. R.; Tuttle, J. G.; Jahromi, A. E.; Dipirro, M. J.; James, B. L.; Sampson, M. A.; Letmate, R. V.

    2017-01-01

    We present the current state of development in passive gas-gap heat switches. This type of switch does not require a separate heater to activate heat transfer but, instead, relies upon the warming of one end due to an intrinsic step in a thermodynamic cycle to raise a getter above a threshold temperature. Above this temperature sequestered gas is released to couple both sides of the switch. This enhances the thermodynamic efficiency of the system and reduces the complexity of the control system. Various gas mixtures and getter configurations will be presented.

  5. Method and apparatus for real-time measurement of fuel gas compositions and heating values

    Science.gov (United States)

    Zelepouga, Serguei; Pratapas, John M.; Saveliev, Alexei V.; Jangale, Vilas V.

    2016-03-22

    An exemplary embodiment can be an apparatus for real-time, in situ measurement of gas compositions and heating values. The apparatus includes a near infrared sensor for measuring concentrations of hydrocarbons and carbon dioxide, a mid infrared sensor for measuring concentrations of carbon monoxide and a semiconductor based sensor for measuring concentrations of hydrogen gas. A data processor having a computer program for reducing the effects of cross-sensitivities of the sensors to components other than target components of the sensors is also included. Also provided are corresponding or associated methods for real-time, in situ determination of a composition and heating value of a fuel gas.

  6. Indirect heating of natural gas using vapor chambers; Aquecimento indireto de gas natural com uso de camaras de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Milanez, Fernando H.; Mantellil, Marcia H.B.; Borges, Thomaz P.F. [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica; Landa, Henrique G. de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2005-07-01

    Operation safety and reliability are major guidelines in the design of city-gate units. Conventional natural gas heaters operate by a indirect mechanism, where liquid water is used to transfer heat by natural convection between the combustion chamber and the natural gas coil. In this work, the concept of vapor chamber is evaluated as an indirect gas heater. In a vapor chamber, liquid water is in contact with the heat source, and vaporizes. The vapor condenses in contact with the heat sink. A reduced scale model was built and tested in order to compare these two heating concepts where the combustion chamber was replaced by electrical cartridge heaters. This engineering model can operate either as a conventional heater or as a vapor chamber. The comparison between the concepts was done by inducing a controlled power to the cartridges and by measuring the resulting temperature distributions. In the novel design, the heat exchanger efficiency increases, and the thermal inertia decreases, compared to the conventional system. The new sealed concept of the chamber prevents water evaporation losses. (author)

  7. Coordination of the gas and district heating grids of the city of Lausanne; Koordinierung der Gas- und Fernwaermenetze der Stadt Lausanne

    Energy Technology Data Exchange (ETDEWEB)

    Bornand, Pierre-Etienne [Stadtwerke Services industriels, Lausanne (Switzerland). Gas et chauffage a distance

    2010-10-15

    In the Swiss city of Lausanne, the gas and district heating grids were combined for better coordination. It is now easier to decide which gas lines will be shut off and which gas lines are still required, and also where the district heating grid needs expanding. Carbon dioxide emissions are getting lower as the district heating grid is expanding, which means a financial gain for the city. (orig.)

  8. Gas and heat dynamics of a micro-scaled atmospheric pressure plasma reference jet

    Science.gov (United States)

    Kelly, Seán; Golda, Judith; Turner, Miles M.; Schulz-von der Gathen, Volker

    2015-11-01

    Gas and heat dynamics of the ‘Cooperation on Science and Technology (COST) Reference Microplasma Jet’ (COST-jet), a European lead reference device for low temperature atmospheric pressure plasma application, are investigated. Of particular interest to many biomedical application scenarios, the temperature characteristics of a surface impacted by the jet are revealed. Schlieren imaging, thermocouple measurements, infrared thermal imaging and numerical modelling are employed. Temperature spatial profiles in the gas domain reveal heating primarily of the helium fraction of the gas mixture. Thermocouple and model temporal data show a bounded exponential temperature growth described by a single characteristic time parameter to reach  ∼63% or (1-1/e) fraction of the temperature increase. Peak temperatures occurred in the gas domain where the carrier jet exits the COST-jet, with values ranging from ambient temperatures to in excess of 100 °C in ‘α-mode’ operation. In a horizontal orientation of the COST-jet a curved trajectory of the helium effluent at low gas flows results from buoyant forces. Gas mixture profiles reveal significant containment of the helium concentrations for a surface placed in close proximity to the COST-jet. Surface heating of a quartz plate follows a similar bounded exponential temporal temperature growth as device heating. Spatial profiles of surface heating are found to correlate strongly to the impacting effluent where peak temperatures occur in regions of maximum surface helium concentration.

  9. Safety provision during heating of coal downcast shafts with gas heat generators using degassed methane

    Directory of Open Access Journals (Sweden)

    В. Р. Алабьев

    2017-06-01

    Together with heat generators of mixed type the article also describes a working principle of heat generator of indirect action type, which to the fullest extent possible meets requirements of Russian Federation legislation and regulation for application of this heat generators in coal mines conditions. The article has a principal working scheme of heat unit layout using this type of generator. It is shown that after development of corresponding normative documents regulating processes of design, construction and operation of heating units using heaters of indirect action, their application in Russian coal mines will be possible without breaking Safety standards and rules.

  10. Geothermics, fuel and gas heat 30 000 lodgings; Geothermie, fuel et gaz chauffent 30 000 logements

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-11-01

    Evry, the Essonne prefecture (France), is equipped with one of the most important French heating plant (196 MW) which combines geothermics, fuel and gas and supplies 350 delivery stations for the sanitary hot water and the heating of lodgings corresponding to about 2 millions of m{sup 2}. This paper describes the historical evolution of the plant and its present day equipment: a central plant with 4 mixed fuel and gas heating plants (147 MW), a double-well geothermal installation (8 MW) and 5 gas heating plants for residential blocks of houses (41 MW). Three complementary systems are used for the remote management and monitoring of the central plant, the sub-plants and the delivery stations. (J.S.)

  11. Effects of N/C Ratio on Solidification Behaviors of Novel Nb-Bearing Austenitic Heat-Resistant Cast Steels for Exhaust Components of Gasoline Engines

    Science.gov (United States)

    Zhang, Yinhui; Li, Mei; Godlewski, Larry A.; Zindel, Jacob W.; Feng, Qiang

    2017-03-01

    In order to comply with more stringent environmental and fuel consumption regulations, novel Nb-bearing austenitic heat-resistant cast steels that withstand exhaust temperatures as high as 1,323 K (1,050 °C) is urgently demanded from automotive industries. In the current research, the solidification behavior of these alloys with variations of N/C ratio is investigated. Directional solidification methods were carried out to examine the microstructural development in mushy zones. Computational thermodynamic calculations under partial equilibrium conditions were performed to predict the solidification sequence of different phases. Microstructural characterization of the mushy zones indicates that N/C ratio significantly influenced the stability of γ-austenite and the precipitation temperature of NbC/Nb(C,N), thereby altering the solidification path, as well as the morphology and distribution of NbC/Nb(C,N) and γ-ferrite. The solidification sequence of different phases predicted by thermodynamic software agreed well with the experimental results, except the specific precipitation temperatures. The generated data and fundamental understanding will be helpful for the application of computational thermodynamic methods to predict the as-cast microstructure of Nb-bearing austenitic heat-resistant steels.

  12. Segmented heat exchanger

    Science.gov (United States)

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  13. A comparative study of the elemental composition of the exhaust emissions of cars powered by liquefied petroleum gas and unleaded petrol

    Science.gov (United States)

    Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia; Ristovski, Zoran D.; Jayaratne, E. Rohan; Kokot, Serge

    Elements emitted from the exhausts of new Ford Falcon Forte cars powered by unleaded petrol (ULP) and liquefied petroleum gas (LPG) were measured on a chassis dynamometer. The measurements were carried out in February, June and August 2001, and at two steady state driving conditions (60 and 80 km h -1). Thirty seven elements were quantified in the exhaust samples by inductively coupled plasma mass spectrometry (ICPMS). The total emission factors of the elements from the exhausts of ULP cars were higher than those of LPG cars at both engine speeds even though high variability in the exhaust emissions from different cars was noted. The effect of the operating conditions such as mileage of the cars, engine speed, fuel and lubricating oil compositions on the emissions was studied. To investigate the effects of these conditions, multivariate data analysis methods were employed including exploratory principal component analysis (PCA), and the multi-criteria decision making methods (MCDM), preference ranking organization method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive aid (GAIA), for ranking the cars on the basis of the emission factors of the elements. PCA biplot of the complete data matrix showed a clear discrimination of the February, June and August emission test results. In addition, (i) platinum group elements (PGE) emissions were separated from each other in the three different clusters viz. Pt with February, Pd with June and Rh with August; (ii) the motor oil related elements, Zn and P, were particularly associated with the June and August tests (these vectors were also grouped with V, Al and Cu); and (iii) highest emissions of most major elements were associated with the August test after the cars have recorded their highest mileage. Extensive analysis with the aid of the MCDM ranking methods demonstrated clearly that cars powered by LPG outperform those powered by ULP. In general, cars tested in June perform better than

  14. New concepts for exhaust gas turbo charging of a four-cylinder direct injection Otto engine; Neue Konzepte zur Abgasturboaufladung eines direkteinspritzenden Vierzylinder-Ottomotors

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Tilo

    2008-07-01

    This work is supposed to be understood as a contribution to developing a new generation of Otto engines, which meet the increasing ecological and economical demands. The charge concept has a key position in this development. Its design in particular at the four cylinder engine that dominates the market and whose charge changes are very specific, proves to be a special challenge. Based upon known techniques new concepts are developed in this work by means of numeric simulation and experiments and then compared with each other under stationary and transient conditions. On the one hand several exhaust gas turbo chargers in form a register and a two-phase charging are combined with a variable control of the outlet valves, on the other hand the shock-back-up changing is evaluated combined with a biturbo system as well as a twin-current turbine. (orig.)

  15. Inverted Fuel Cell: Room-Temperature Hydrogen Separation from an Exhaust Gas by Using a Commercial Short-Circuited PEM Fuel Cell without Applying any Electrical Voltage.

    Science.gov (United States)

    Friebe, Sebastian; Geppert, Benjamin; Caro, Jürgen

    2015-06-26

    A short-circuited PEM fuel cell with a Nafion membrane has been evaluated in the room-temperature separation of hydrogen from exhaust gas streams. The separated hydrogen can be recovered or consumed in an in situ olefin hydrogenation when the fuel cell is operated as catalytic membrane reactor. Without applying an outer electrical voltage, there is a continuous hydrogen flux from the higher to the lower hydrogen partial pressure side through the Nafion membrane. On the feed side of the Nafion membrane, hydrogen is catalytically split into protons and electrons by the Pt/C electrocatalyst. The protons diffuse through the Nafion membrane, the electrons follow the short-circuit between the two brass current collectors. On the cathode side, protons and electrons recombine, and hydrogen is released. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. High Temperature Resistant Exhaust Valve Spindle

    DEFF Research Database (Denmark)

    Bihlet, Uffe Ditlev

    of the engine, new high temperature alloys are required for a specific engine component, the exhaust valve spindle. Two alloys are used for an exhaust valve spindle; one for the bottom of the spindle, and one for the spindle seat. Being placed in the exhaust gas stream, combustion products such as V2O5 and Na2...

  17. Role of average speed in N₂O exhaust emissions as greenhouse gas in a huge urban zone (MVMZ): would we need a cold sun?

    Science.gov (United States)

    Castillo, S; Mac-Beath, I; Mejia, I; Camposeco, R; Bazan, G; Morán-Pineda, M; Carrera, R; Gómez, R

    2012-05-15

    Nowadays, the drastic pollution problems, some of them related with greenhouse gas emissions, have promoted important attempts to face and diminish the global warming effects on the Mexico Valley Metropolitan Zone (MVMZ) as well as on the huge urban zones around the world. To reduce the exhaust gas emissions, many efforts have been carried out to reformulate fuels and design new catalytic converters; however, it is well known that other variables such as socio-economic and transport structure factors also play an important role around this problem. The present study analyzes the roles played by several commonly-used three-way catalytic converters (TWC) and the average traffic speed in the emission of N(2)O as greenhouse gas. According to this study, by increasing the average traffic flow and avoiding constant decelerations (frequent stops) during common trips, remarkable environmental and economic benefits could be obtained due to the diminution of N(2)O and other contaminant emissions such as ammonia (NH(3)) and even CO(2) with the concomitant reduced fossil fuel consumption. The actions mentioned above could be highly viable to diminish, in general, the global warming effects and contamination problems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Quantification of benzene, toluene, ethylbenzene and o-xylene in internal combustion engine exhaust with time-weighted average solid phase microextraction and gas chromatography mass spectrometry.

    Science.gov (United States)

    Baimatova, Nassiba; Koziel, Jacek A; Kenessov, Bulat

    2015-05-11

    A new and simple method for benzene, toluene, ethylbenzene and o-xylene (BTEX) quantification in vehicle exhaust was developed based on diffusion-controlled extraction onto a retracted solid-phase microextraction (SPME) fiber coating. The rationale was to develop a method based on existing and proven SPME technology that is feasible for field adaptation in developing countries. Passive sampling with SPME fiber retracted into the needle extracted nearly two orders of magnitude less mass (n) compared with exposed fiber (outside of needle) and sampling was in a time weighted-averaging (TWA) mode. Both the sampling time (t) and fiber retraction depth (Z) were adjusted to quantify a wider range of Cgas. Extraction and quantification is conducted in a non-equilibrium mode. Effects of Cgas, t, Z and T were tested. In addition, contribution of n extracted by metallic surfaces of needle assembly without SPME coating was studied. Effects of sample storage time on n loss was studied. Retracted TWA-SPME extractions followed the theoretical model. Extracted n of BTEX was proportional to Cgas, t, Dg, T and inversely proportional to Z. Method detection limits were 1.8, 2.7, 2.1 and 5.2 mg m(-3) (0.51, 0.83, 0.66 and 1.62 ppm) for BTEX, respectively. The contribution of extraction onto metallic surfaces was reproducible and influenced by Cgas and t and less so by T and by the Z. The new method was applied to measure BTEX in the exhaust gas of a Ford Crown Victoria 1995 and compared with a whole gas and direct injection method. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. ENERGY SUPPLY OF COMMERCIAL GREENHOUSE WITH THE GAS DRIVEN HEAT PUMP

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2013-08-01

    Full Text Available Abstract: The aim of the work is to develop energy efficient schemes of industrial greenhouse designed for year-round production of plants that requires year-round maintenance of strongly prescribed temperature and humidity inside the greenhouse. The complex "gas driven “water-air” heat pump – electric generator" (for use during the heating season as well as the "gas driven heat pump “water-air” – electric generator – desiccant - evaporative chiller" which work in the off-season. The developed system produces heat and electricity (during the heating season as well as cold and electricity (the rest of the year. Comparative analyses of greenhouse cooling by water and air cooling systems have been performed. Proposed structures have a high efficiency as compared with conventional circuits (boiler - chiller.

  20. Simulation of boiling pools with internal heat sources by gas injection. [LMFBR core meltdown

    Energy Technology Data Exchange (ETDEWEB)

    Luk, A.C.H.; Ganguli, A.; Bankoff, S.G.

    1977-07-29

    Heat transfer from the sides and bottom of an open non-boiling liquid pool with spatially uniform internal gas injection was studied experimentally, both in transient and in steady state. The results were compared with experimental data for a boiling pool without permanent gas injection undertaken at Argonne National Laboratory. Typical Nusselt number versus Reynolds number plots showed that heat transfer rates were much higher in the gassy pool due to more efficient circulation. A correction was applied to estimate the surface evaporation effect under boiling conditions. Bubble size and distribution effects controlled the heat transfer rates. Vertical void fraction profiles were inferred from local static pressure measurements. A modified Grashof number, in terms of the average void fraction, was also used to correlate the data for horizontal heat flow. The bottom and side heat loss rates were about equal, which would indicate that the pool might retain its shape as it sinks into the support material.

  1. Radon and Thoron Measured in Petrol and Gas-oil Exhaust Fumes by Using CR-39 and LR-115 II Nuclear Track Detectors: Radiation Doses to the Respiratory Tract of Mechanic Workers.

    Science.gov (United States)

    Misdaq, M A; Chaouqi, A; Ouguidi, J; Touti, R; Mortassim, A

    2015-06-01

    Mechanic workers are exposed to exhaust fumes when controlling vehicle engines in motion inside repair shops. To assess radiation doses due to radon short-lived progeny from the inhalation of exhaust fumes by mechanic workers, concentrations of these radionuclides were measured in petrol (gasoline) and gas-oil exhaust fumes by evaluating mean critical angles of etching of the CR-39 and LR-115 type II SSNTDs for alpha particles emitted by the radon and thoron decay series. Committed effective doses due to ²¹⁸Po and ²¹⁴Po short-lived radon decay products from the inhalation of petrol and gas-oil exhaust fumes by workers were evaluated. A maximum value of 1.35 mSv y⁻¹ due to radon short-lived decay products from the inhalation of gas-oil exhaust fumes by mechanic workers was found, which is lower than the (3-10 mSv y⁻¹) dose limit interval for workers.

  2. Modeling of Aerobrake Ballute Stagnation Point Temperature and Heat Transfer to Inflation Gas

    Science.gov (United States)

    Bahrami, Parviz A.

    2012-01-01

    A trailing Ballute drag device concept for spacecraft aerocapture is considered. A thermal model for calculation of the Ballute membrane temperature and the inflation gas temperature is developed. An algorithm capturing the most salient features of the concept is implemented. In conjunction with the thermal model, trajectory calculations for two candidate missions, Titan Explorer and Neptune Orbiter missions, are used to estimate the stagnation point temperature and the inflation gas temperature. Radiation from both sides of the membrane at the stagnation point and conduction to the inflating gas is included. The results showed that the radiation from the membrane and to a much lesser extent conduction to the inflating gas, are likely to be the controlling heat transfer mechanisms and that the increase in gas temperature due to aerodynamic heating is of secondary importance.

  3. Heat exchanger design considerations for high temperature gas-cooled reactor (HTGR) plants

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, C.F.; Vrable, D.L.; Van Hagan, T.H.; King, J.H.; Spring, A.H.

    1980-02-01

    Various aspects of the high-temperature heat exchanger conceptual designs for the gas turbine (HTGR-GT) and process heat (HTGR-PH) plants are discussed. Topics include technology background, heat exchanger types, surface geometry, thermal sizing, performance, material selection, mechanical design, fabrication, and the systems-related impact of installation and integration of the units in the prestressed concrete reactor vessel. The impact of future technology developments, such as the utilization of nonmetallic materials and advanced heat exchanger surface geometries and methods of construction, is also discussed.

  4. Denuder for measuring emissions of gaseous organic exhaust gas constituents; Denuder zur Emissionsmessung von gasfoermigen organischen Abgasinhaltsstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Gerchel, B.; Jockel, W.; Kallinger, G.; Niessner, R.

    1997-05-01

    Industrial plants which emit carcinogenic or other noxious substances should be given top priority in any policy to ward off harmful environmental effects. This also applies to many volatile and semi-volatile air constituents such as volatile aliphatic carbonyls or amines. To date there are no satisfactory methods for determining trace organic components of exhaust gases. It is true that aldehydes are considered in the VDI Guideline 3862, but the measuring methods given there are based on absorption in liquids and are accordingly difficult to use and show a high cross-sensitivity for other substances. No VDI Guideline exists to date on amine emissions. In view of the complexity of exhaust gases a selective enrichment of certain families of substances would appear indicated. Sampling trouble could be reduced if it was possible only to accumulate the gaseous phase, or even just one family of gaseous constituents. A particularly suitable air sampling method is that of diffusion separation. These diffusion separators (denuders) are well known as a powerful measuring system which is able to accumulate trace pollutants in the outside air. The purpose of the present study was to find out whether the concept of diffusion separation is also applicable to emission monitoring, and in particular whether it is suitable for detecting volatile aliphatic aldehydes and amines (primary and secondary) at extremely low concentrations (<10 ppb). (orig./SR) [Deutsch] Fuer Anlagen mit Emissionen von krebserzeugenden und gesundheitsgefaehrdenden Stoffen ergibt sich ein besonderer Handlungsbedarf zum Schutz vor schaedlichen Umwelteinwirkungen. Zu diesen Stoffen gehoeren auch viele leicht- und mittelfluechtigen Luftinhaltsstoffe, wie z.B. die leichtfluechtigen aliphatischen Carbonyle oder Amine. Fuer organische Komponenten, die nur in geringen Konzentrationen im Abgas vorkommen, existieren bisher keine zufriedenstellenden Messverfahren. Fuer die Aldehyde liegt zwar die VDI-Richtlinie 3862

  5. Thermal Analysis of the Divertor Primary Heat Transfer System Piping During the Gas Baking Process

    Energy Technology Data Exchange (ETDEWEB)

    Yoder Jr, Graydon L [ORNL; Harvey, Karen [ORNL; Ferrada, Juan J [ORNL

    2011-02-01

    A preliminary analysis has been performed examining the temperature distribution in the Divertor Primary Heat Transfer System (PHTS) piping and the divertor itself during the gas baking process. During gas baking, it is required that the divertor reach a temperature of 350 C. Thermal losses in the piping and from the divertor itself require that the gas supply temperature be maintained above that temperature in order to ensure that all of the divertor components reach the required temperature. The analysis described in this report was conducted in order to estimate the required supply temperature from the gas heater.

  6. Public Colleges Feel the Heat from Gas Boom

    Science.gov (United States)

    Carlson, Scott

    2012-01-01

    Shale-gas fracking is sure to bring all kinds of changes to Ohio. But what administrators and trustees at Ohio University are concerned about at the moment is who will control whether their land gets fracked. In years past, individual boards of trustees, for the most part, controlled the land at the state's colleges and universities. But a new law…

  7. 40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.

    Science.gov (United States)

    2010-07-01

    ... velocity, is inversely proportional to the square root of the gas temperature, and is computed continuously... ±5 percent. (The volumetric sample flow rate shall be varied inversely with the square root of the... determining CVS flow rates are detailed in “Calculation of Emissions and Fuel Economy When Using Alternative...

  8. A waste heat boiler concept for co-generation applications on land and at sea

    Energy Technology Data Exchange (ETDEWEB)

    Riet, F. van (Louvain Univ. (Belgium) Clayton Industries (BE))

    1992-02-01

    Heat recovery systems for exhaust gases have been developed for both industrial and marine applications. Clayton Exhaust Gas Boilers are used on cargo ships, chemical carriers, ferries, reefer vessels, gas tankers, rigs, fish processing vessels and a wide range of other types of ship. Generally, an installation consists of a combination of one or more fired steam generators and an exhaust gas steam generator or boiler. This means that the fired unit(s) are in operation whilst the ship is in port and the exhaust gas unit is producing steam whilst the ship is at sea. Typical industrial applications for Waste Heat Recovery Systems are in combination with incinerators, diesel engines, gas turbines, glass furnaces, enamel ovens, stress relieving ovens etc. Clayton Waste Heat Recovery Systems can be applied to waste gases ranging from 200{sup o}C to 1400{sup o}C and rated from 680 kg/h to 59.000 kg/h. (Author).

  9. Spatiotemporal study of gas heating mechanisms in a radio-frequency electrothermal plasma micro-thruster

    Directory of Open Access Journals (Sweden)

    Amelia eGreig

    2015-10-01

    Full Text Available A spatiotemporal study of neutral gas temperature during the first 100 s of operation for a radio-frequency electrothermal plasma micro-thruster operating on nitrogen at 60 W and 1.5 Torr is performed to identify the heating mechanisms involved. Neutral gas temperature is estimated from rovibrational band fitting of the nitrogen second positive system. A set of baffles are used to restrict the optical image and separate the heating mechanisms occurring in the central bulk discharge region and near the thruster walls.For each spatial region there are three distinct gas heating mechanisms being fast heating from ion-neutral collisions with timescales of tens of milliseconds, intermediate heating with timescales of 10 s from ion bombardment on the inner thruster tube surface creating wall heating, and slow heating with timescales of 100 s from gradual warming of the entire thruster housing. The results are discussed in relation to optimising the thermal properties of future thruster designs.

  10. Method for the removal of smut, fine dust and exhaust gas particles, particle catch arrangement for use in this method and use of the particle catch arrangement to generate a static electric field

    NARCIS (Netherlands)

    Ursem, W.N.J.; Marijnissen, J.C.; Roos, R.A.

    2007-01-01

    This inventions provides a method for the removal of smut, fine dust and exhaust gas particles from polluted air comprising providing a particle catch arrangement with a charged surface, the particle catch arrangement being arranged to generate a static electric field, wherein the electric field is

  11. Greenhouse gas abatement cost curves of the residential heating market. A microeconomic approach

    Energy Technology Data Exchange (ETDEWEB)

    Dieckhoener, Caroline; Hecking, Harald

    2012-10-15

    In this paper, we develop a microeconomic approach to deduce greenhouse gas abatement cost curves of the residential heating sector. By accounting for household behavior, we find that welfare-based abatement costs are generally higher than pure technical equipment costs. Our results are based on a microsimulation of private households' investment decision for heating systems until 2030. The households' investment behavior in the simulation is derived from a discrete choice estimation which allows investigating the welfare costs of different abatement policies in terms of the compensating variation and the excess burden. We simulate greenhouse gas abatements and welfare costs of carbon taxes and subsidies on heating system investments until 2030 to deduce abatement curves. Given utility maximizing households, our results suggest a carbon tax to be the welfare efficient policy. Assuming behavioral misperceptions instead, a subsidy on investments might have lower marginal greenhouse gas abatement costs than a carbon tax.

  12. A direct resistively heated gas chromatography column with heating and sensing on the same nickel element.

    Science.gov (United States)

    Stearns, Stanley D; Cai, Huamin; Koehn, J Art; Brisbin, Martin; Cowles, Chris; Bishop, Chris; Puente, Santos; Ashworth, Dale

    2010-07-02

    Nickel clad or nickel wired fused silica column bundles were constructed and evaluated. The nickel sheathing or wire functions not only as the heating element for direct resistive heat, but also as the temperature sensor, since nickel has a large resistive temperature coefficient. With this method the temperature controller is able to apply power and measure the temperature simultaneously on the same nickel element, which can effectively avoid the temperature overshoot caused by any delayed response of the sensor to the heating element. This approach also eliminates the cool spot where a separate sensor touches the column. There are some other advantages to the column bundle structure: (1) the column can be heated quickly because of the direct heating and the column's low mass, shortening analysis time. We demonstrate a maximum heating rate of 13 degrees C/s (800 degrees C/min). (2) Cooling time is also short, increasing sample throughput. The column drops from 360 degrees C to 40 degrees C is less than 1 min. (3) Power consumption is very low - 1.7 W/m (8.5 W total) for a 5 m column and 0.69 W/m (10.4 W total) for a 15 m column when they are kept at 200 degrees C isothermally. With temperature programming, the power consumption for a 5 m column is less then 70 W for an 800 degrees C/min ramp to 350 degrees C. (4) The column bundle is small, with a diameter of only about 2.25 in. All these advantages make the column bundle ideal for fast GC analysis or portable instruments. Column efficiencies and retention time repeatability have been evaluated and compared with the conventional oven heating method in this study. For isothermal conditions, the column efficiencies are measured by effective theoretical plate number. It was found that the plate number with resistive heat is always less than with oven heat, due to uneven heat in the column bundle. However, the loss is not significant - an average of about 1.5% for the nickel clad column and 4.5% for the nickel wired

  13. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Edward Levy; Harun Bilirgen; John DuPoint

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: (1) An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing high-moisture, low rank coals. (2) Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. (3) Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. (4) Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. (5) Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. (6) Condensed flue gas water treatment needs and costs. (7) Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. (8) Results of cost-benefit studies of condensing heat exchangers.

  14. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Edward; Bilirgen, Harun; DuPont, John

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: • An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing highmoisture, low rank coals. • Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. • Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. • Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. • Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. • Condensed flue gas water treatment needs and costs. • Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. • Results of cost-benefit studies of condensing heat exchangers.

  15. Effect of flue gas recirculation on heat transfer in a supercritical circulating fluidized bed combustor

    Directory of Open Access Journals (Sweden)

    Błaszczuk Artur

    2015-09-01

    Full Text Available This paper focuses on assessment of the effect of flue gas recirculation (FGR on heat transfer behavior in 1296t/h supercritical coal-fired circulating fluidized bed (CFB combustor. The performance test in supercritical CFB combustor with capacity 966 MWth was performed with the low level of flue gas recirculation rate 6.9% into furnace chamber, for 80% unit load at the bed pressure of 7.7 kPa and the ratio of secondary air to the primary air SA/PA = 0.33. Heat transfer behavior in a supercritical CFB furnace between the active heat transfer surfaces (membrane wall and superheater and bed material has been analyzed for Geldart B particle with Sauter mean diameters of 0.219 and 0.246 mm. Bed material used in the heat transfer experiments had particle density of 2700 kg/m3. A mechanistic heat transfer model based on cluster renewal approach was used in this work. A heat transfer analysis of CFB combustion system with detailed consideration of bed-to-wall heat transfer coefficient distributions along furnace height is investigated. Heat transfer data for FGR test were compared with the data obtained for representative conditions without recycled flue gases back to the furnace through star-up burners.

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

    Science.gov (United States)

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

    1985-01-01

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

  17. Techniques in Gas-Phase Thermolyses. Part 6. Pulse Pyrolysis: Gas Kinetic Studies in an Inductively Heated Flow Reactor

    DEFF Research Database (Denmark)

    Egsgaard, Helge; Bo, P.; Carlsen, Lars

    1985-01-01

    A prototype of an inductively heated flow reactor for gas kinetic studies is presented. The applicability of the system, which is based on a direct coupling between the reactor and the ion source of a mass spectrometer, is illustrated by investigations of a series of simple bond fission reactions....... The method permits the direct determination of low-pressure rate constants, the transformation to high-pressure values, and correspondingly evaluation of activation parameters, being derived by means of an empirical effective temperature approach.......A prototype of an inductively heated flow reactor for gas kinetic studies is presented. The applicability of the system, which is based on a direct coupling between the reactor and the ion source of a mass spectrometer, is illustrated by investigations of a series of simple bond fission reactions...

  18. District Heating using a gas-motor-driven heat pump - result checking; Erfolgskontrolle. Heizzentrale mit indirekter Gasmotor-Waermepumpe. Berufsschulen Bern-Lorraine

    Energy Technology Data Exchange (ETDEWEB)

    Eggen, B.; Lanz, S.

    2003-07-01

    This final report for the Swiss Federal Office of Energy presents the results of a project that evaluated the operation of a district heating scheme that supplies various school and college buildings, residential buildings and Berne's Botanical Gardens with heat. This pilot and demonstration system comprises an indirect gas motor heat pump with co-generation unit and an electrically-driven heat pump. In order to achieve a high performance ratio the co-generation unit was additionally equipped with a heat-recovery heat pump which condenses the waste gas and recovers radiation heat losses. The implementation of the district heating project was done in stages to meet annual heat demands of around 6'500 MWh. About 50% of these demands are met by the indirect gas motor heat pump. Figures are presented on the optimisation of heat utilisation from ground water which permitted an improvement in the total efficiency of the plant of around 30% compared with a conventional installation. The authors state that, with this installation, it could be demonstrated in an exemplary fashion that heat pumps can also be installed in existing, non-renovated buildings. In the planning of such heat pump systems they recommend that special attention be paid to the overall performance ratio, and that the rate of flow of the heat source and system temperatures be taken into account.

  19. Green's function solution to heat transfer of a transparent gas through a tube

    Science.gov (United States)

    Frankel, J. I.

    1989-01-01

    A heat transfer analysis of a transparent gas flowing through a circular tube of finite thickness is presented. This study includes the effects of wall conduction, internal radiative exchange, and convective heat transfer. The natural mathematical formulation produces a nonlinear, integrodifferential equation governing the wall temperature and an ordinary differential equation describing the gas temperature. This investigation proposes to convert the original system of equations into an equivalent system of integral equations. The Green's function method permits the conversion of an integrodifferential equation into a pure integral equation. The proposed integral formulation and subsequent computational procedure are shown to be stable and accurate.

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

    Science.gov (United States)

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

    2014-04-01

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

  1. Assessment of Zr-Fe-V getter alloy for gas-gap heat switches

    Science.gov (United States)

    Prina, M.; Kulleck, J. G.; Bowman, R. C., Jr.

    2000-01-01

    A commercial Zr-V-Fe alloy (i.e., SAES Getters trade name alloy St-172) has been assessed as reversible hydrogen storage material for use in actuators of gas gap heat switches. Two prototype actuators containing the SAES St-172 material were built and operated for several thousand cycles to evaluate performance of the metal hydride system under conditions simulating heat switch operation.

  2. Flow and heat transfer investigations in swirl tubes for gas turbine blade cooling

    OpenAIRE

    Biegger, Christoph

    2017-01-01

    A swirl tube is a very effective cooling technique for high thermal loaded components like gas turbine blades. Such a tube consists of one or more tangential inlet jets, which induce a highly 3D swirling flow. This swirling flow is characterized by large velocities near the wall and an enhanced turbulence in the tube which both increase the convective heat transfer. In the present work, the flow phenomena and the heat transfer in swirl tubes are studied experimentally and numerically. Therefo...

  3. Solar-assisted gas-energy water-heating feasibility for apartments

    Science.gov (United States)

    Davis, E. S.

    1975-01-01

    Studies of residential energy use, solar-energy technology for buildings, and the requirements for implementing technology in the housing industry led to a project to develop a solar water heater for apartments. A design study for a specific apartment was used to establish a solar water-heater cost model which is based on plumbing contractor bids and manufacturer estimates. The cost model was used to size the system to minimize the annualized cost of hot water. The annualized cost of solar-assisted gas-energy water heating is found to be less expensive than electric water heating but more expensive than gas water heating. The feasibility of a natural gas utility supplying the auxiliary fuel is evaluated. It is estimated that gas-utilizing companies will find it profitable to offer solar water heating as part of a total energy service option or on a lease basis when the price of new base-load supplies of natural gas reaches $2.50-$3.00 per million Btu.

  4. Polycyclic aromatic hydrocarbons (PAHs) in exhaust emissions from diesel engines powered by rapeseed oil methylester and heated non-esterified rapeseed oil

    Science.gov (United States)

    Vojtisek-Lom, Michal; Czerwinski, Jan; Leníček, Jan; Sekyra, Milan; Topinka, Jan

    2012-12-01

    Polycyclic aromatic hydrocarbons (PAHs) of exhaust emissions were studied in four direct-injection turbocharged four-cylinder diesel engines, with power ratings of 90-136 kW. The engines were operated on biodiesel (B-100), a blend of 30% biodiesel in diesel fuel (B-30), and heated rapeseed oil (RO) in two independent laboratories. Diesel particle filters (DPF) and selective catalytic reduction (SCR) systems were used with B-30 and B-100. Concentrations of individual PAHs sampled in different substrates (quartz, borosilicate fiber and fluorocarbon membrane filters, polyurethane foam) were analyzed using different methods. Benzo[a]pyrene toxic equivalents (BaP TEQ) were calculated using different sets of toxic equivalency factors (TEF). Operation on B-100 without aftertreatment devices, compared to diesel fuel, yielded a mean reduction in PAHs of 73%, consistent across engines and among TEF used. A lower PAH reduction was obtained using B-30. The BaP TEQ reductions on DPF were 91-99% using B-100, for one non-catalyzed DPF, and over 99% in all other cases. The BaP TEQ for heated RO were higher than those for B-100 and one half lower to over twice as high as that of diesel fuel. B-100 and RO samples featured, compared to diesel fuel, a relatively high share of higher molecular weight PAH and a relatively low share of lighter PAHs. Using different sets of TEF or different detection methods did not consistently affect the observed effect of fuels on BaP TEQ. The compilation of multiple tests was helpful for discerning emerging patterns. The collection of milligrams of particulate matter per sample was generally needed for quantification of all individual PAHs.

  5. Gas heating and plasma expansion in pulsed microwave-excited microplasmas

    Science.gov (United States)

    Hoskinson, Alan R.; Yared, Alexander; Hopwood, Jeffrey

    2015-10-01

    Microwave resonators are used to generate microplasmas in atmospheric-pressure argon and helium. We present observations of the transient behavior of a microplasma after a fast increase in power, including time-resolved photography and spectroscopic gas temperature measurements. The results show that in argon both plasma filamentation and gas heating continue out to millisecond time scales, while helium microplasmas reach steady-state conditions after a few microseconds.

  6. 40 CFR 1065.330 - Exhaust-flow calibration.

    Science.gov (United States)

    2010-07-01

    ... recommend that you use a calibration subsonic venturi or ultrasonic flow meter and simulate exhaust temperatures by incorporating a heat exchanger between the calibration meter and the exhaust-flow meter. If you... Exhaust-flow calibration. (a) Calibrate exhaust-flow meters upon initial installation. Follow the...

  7. Composition of pyrolysis gas from oil shale at various stages of heating

    Science.gov (United States)

    Martemyanov, S. M.; Bukharkin, A. A.; Koryashov, I. A.; Ivanov, A. A.

    2017-05-01

    Underground, the pyrolytic conversion of an oil shale in the nearest future may become an alternative source of a fuel gas and a synthetic oil. The main scientific problem in designing this technology is to provide a methodology for determination of the optimal mode of heating the subterranean formation. Such a methodology must allow predicting the composition of the pyrolysis products and the energy consumption at a given heating rate of the subterranean formation. The paper describes the results of heating of the oil shale fragments in conditions similar to the underground. The dynamics of composition of the gaseous products of pyrolysis are presented and analyzed.

  8. Method for removing soot from exhaust gases

    Energy Technology Data Exchange (ETDEWEB)

    Suib, Steven L.; Dharmarathna, D. A. Saminda; Pahalagedara, Lakshitha R.

    2018-01-16

    A method for oxidizing soot from diesel exhaust gas from a diesel engine. The method involves providing a diesel particulate filter for receiving the diesel exhaust gas; coating a catalyst composition on the diesel particulate filter; and contacting the soot from the diesel exhaust gas with the catalyst coated diesel particulate filter at a temperature sufficient to oxidize the soot to carbon dioxide. The catalyst composition is a doped or undoped manganese oxide octahedral molecular sieve (OMS-2) material. A diesel exhaust gas treatment system that includes a diesel particulate filter for receiving diesel exhaust gas from a diesel engine and collecting soot; and a catalyst composition coated on the diesel particulate filter. The catalyst composition is a doped or undoped manganese oxide octahedral molecular sieve (OMS-2).

  9. Gas-Assisted Heating Technology for High Aspect Ratio Microstructure Injection Molding

    Directory of Open Access Journals (Sweden)

    Shia-Chung Chen

    2013-01-01

    Full Text Available A hot gas is used for heating the cavity surface of a mold. Different mold gap sizes were designed. The mold surface temperature was heated to above the glass transition temperature of the plastic material, and the mold then closed for melt filling. The cavity surface can be heated to 130°C to assist the melt filling of the microfeatures. Results show that hot gas heating can improve the filling process and achieve 91% of the high aspect ratio microgrooves (about 640.38 μm of the maximum of 700 μm. The mold gap size strongly affects the heating speed and heating uniformity. Without surface preheating, the center rib is the highest. When the heating target temperature is 90°C or 100°C, the three microribs have a good uniformity of height. However, when the target temperature exceeds 100°C, the left side rib is higher than the other ribs.

  10. Wall heat transfer in gas-fired furnaces: Effect of radiation modelling

    Directory of Open Access Journals (Sweden)

    Vondál J.

    2015-06-01

    Full Text Available The purpose of this work is to study heat transfer to cooled walls in a MW-scale laboratory furnace with a dominating thermal radiation component. Experiment is performed in a specially designed combustion chamber with segmental water-cooled walls and profile of absorbed heat flux is measured along the flame. Non-premixed natural gas flame is stabilized by a guide-vane swirler. The unsteady governing equations of turbulent flow are solved by a finite-volume code with a two-equation k-ε realizable turbulence model, a combination of first-order and second-order upwind schemes and implicit time integration. The coupling of pressure with velocity is treated by SIMPLE (semi-implicit method for pressure-linked equations algorithm. Radiative heat transfer as the main heat transfer method is modelled with special care by discrete ordinates method and gas absorption coefficient is calculated by two alternatives of WSGGM (weighted sum of grey gases model. The predicted total heat transfer rate is found to depend strongly on method chosen for the computation of mean beam length. The results of numerical simulations show that overall heat transfer in a process furnace can be successfully predicted, while heat flux profile along the flame is more difficult to predict accurately. Good engineering accuracy is nevertheless achievable with reasonable computational resources. The trend of deviations is reported, which is useful for the interpretation of practical predictions of process furnaces (fired heaters.

  11. Investigations of thermal barrier coatings of turbine parts using gas flame heating

    Science.gov (United States)

    Lepeshkin, A. R.; Bichkov, N. G.; Ilinskaja, O. I.; Nazarov, V. V.

    2017-09-01

    The development of methods for the calculated and experimental investigations thermal barrier coatings and thermal state of gas-turbine engine parts with a thermal barrier coatings is actual work. The gas flame heating was demonstrated to be effectively used during investigations of a thermal ceramic barrier coatings and thermal state of such gas-turbine engine parts with a TBC as the cooled turbine blades and vanes and combustion liner components. The gas-flame heating is considered to be preferable when investigating the gas-turbine engine parts with a TBC in the special cases when both the convective and radiant components of thermal flow are of great importance. The small-size rig with gas-flame flow made it possible to conduct the comparison investigations with the purpose of evaluating the efficiency of thermal protection of the ceramic deposited thermal barrier coatings on APS and EB techniques. The developed design-experiment method was introduced in bench tests of turbine blades and combustion liner components of gas turbine engines.

  12. Design of a concentric heat exchanger using computational fluid dynamics as design tool

    NARCIS (Netherlands)

    Oosterhuis, Joris; Bühler, Simon; wilcox, D; van der Meer, Theodorus H.

    2013-01-01

    A concentric gas-to-gas heat exchanger is designed for application as a recuperator in the domestic boiler industry. The recuperator recovers heat from the exhaust gases of a combustion process to preheat the ingoing gaseous fuel mixture resulting in increased fuel efficiency. This applied study

  13. Operation of an ADR using helium exchange gas as a substitute for a failed heat switch

    Science.gov (United States)

    Shirron, P.; DiPirro, M.; Kimball, M.; Sneiderman, G.; Porter, F. S.; Kilbourne, C.; Kelley, R.; Fujimoto, R.; Yoshida, S.; Takei, Y.; Mitsuda, K.

    2014-11-01

    The Soft X-ray Spectrometer (SXS) is one of four instruments on the Japanese Astro-H mission, which is currently planned for launch in late 2015. The SXS will perform imaging spectroscopy in the soft X-ray band (0.3-12 keV) using a 6 × 6 pixel array of microcalorimeters cooled to 50 mK. The detectors are cooled by a 3-stage adiabatic demagnetization refrigerator (ADR) that rejects heat to either a superfluid helium tank (at 1.2 K) or to a 4.5 K Joule-Thomson (JT) cryocooler. Four gas-gap heat switches are used in the assembly to manage heat flow between the ADR stages and the heat sinks. The engineering model (EM) ADR was assembled and performance tested at NASA/GSFC in November 2011, and subsequently installed in the EM dewar at Sumitomo Heavy Industries, Japan. During the first cooldown in July 2012, a failure of the heat switch that linked the two colder stages of the ADR to the helium tank was observed. Operation of the ADR requires some mechanism for thermally linking the salt pills to the heat sink, and then thermally isolating them. With the failed heat switch unable to perform this function, an alternate plan was devised which used carefully controlled amounts of exchange gas in the dewar's guard vacuum to facilitate heat exchange. The process was successfully demonstrated in November 2012, allowing the ADR to cool the detectors to 50 mK for hold times in excess of 10 h. This paper describes the exchange-gas-assisted recycling process, and the strategies used to avoid helium contamination of the detectors at low temperature.

  14. Operation of an ADR Using Helium Exchange Gas as a Substitute for a Failed Heat Switch

    Science.gov (United States)

    Shirron, P.; DiPirro, M.; Kimball, M.; Sneiderman, G.; Porter, F. S.; Kilbourne, C.; Kelley, R.; Fujimoto, R.; Yoshida, S.; Takei, Y.; hide

    2014-01-01

    The Soft X-ray Spectrometer (SXS) is one of four instruments on the Japanese Astro-H mission, which is currently planned for launch in late 2015. The SXS will perform imaging spectroscopy in the soft X-ray band (0.3-12 keV) using a 6 6 pixel array of microcalorimeters cooled to 50 mK. The detectors are cooled by a 3-stage adiabatic demagnetization refrigerator (ADR) that rejects heat to either a superfluid helium tank (at 1.2 K) or to a 4.5 K Joule-Thomson (JT) cryocooler. Four gas-gap heat switches are used in the assembly to manage heat flow between the ADR stages and the heat sinks. The engineering model (EM) ADR was assembled and performance tested at NASA/GSFC in November 2011, and subsequently installed in the EM dewar at Sumitomo Heavy Industries, Japan. During the first cooldown in July 2012, a failure of the heat switch that linked the two colder stages of the ADR to the helium tank was observed. Operation of the ADR requires some mechanism for thermally linking the salt pills to the heat sink, and then thermally isolating them. With the failed heat switch unable to perform this function, an alternate plan was devised which used carefully controlled amounts of exchange gas in the dewar's guard vacuum to facilitate heat exchange. The process was successfully demonstrated in November 2012, allowing the ADR to cool the detectors to 50 mK for hold times in excess of 10 h. This paper describes the exchange-gas-assisted recycling process, and the strategies used to avoid helium contamination of the detectors at low temperature.

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

    Science.gov (United States)

    Povinelli, Louis A.

    2001-01-01

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

  16. Off-gas characteristics of liquid-fed joule-heated ceramic melters

    Science.gov (United States)

    Goles, R. W.; Sevigny, G. J.

    1982-06-01

    The off gas characteristics of liquid fed joule heated ceramic meters were investigated as a function of melter operational condition and simulated waste feed composition. The identity and behavior patterns of gaseous emissions, the characteristics of melter generated aerosols, the nature and magnitude of melter effluent losses and the factors affecting melter operational performance were established.

  17. Progress towards understanding and predicting convection heat transfer in the turbine gas path

    Science.gov (United States)

    Simoneau, Robert J.; Simon, Frederick F.

    1992-01-01

    A new era is drawing in the ability to predict convection heat transfer in the turbine gas path. We feel that the technical community now has the capability to mount a major assault on this problem, which has eluded significant progress for a long time. We hope to make a case for this bold statement by reviewing the state of the art in three major heat transfer, configuration-specific experiments, whose data have provided the big picture and guided both the fundamental modeling research and the code development. Following that, we review progress and directions in the development of computer codes to predict turbine gas path heat transfer. Finally, we cite examples and make observations on the more recent efforts to do all this work in a simultaneous, interactive, and more synergistic manner. We conclude with an assessment of progress, suggestions for how to use the current state of the art, and recommendations for the future.

  18. COMPARISON OF CO2-EMISSIONS OF HOUSEHOLDS HEATED BY NATURAL GAS AND FIREWOOD

    Directory of Open Access Journals (Sweden)

    MÓNIKA PALÁDI

    2013-12-01

    Full Text Available In terms of climate protection, one of the most important questions is the reduction of the GHG emission. In this study, I compared CO2 -emission of households heated by natural gas and firewood, which had similar heated area and volume of air, considering the carbon-dioxide absorbing of forests of the households heated by firewood. Natural gas is a fossil fuel; however, the firewood (solid biomass is a renewable energy resource. One of the main features of renewable energy sources is to get into the atmosphere less CO2 than fossil fuels. The renewable energy resources emit into the air just as much CO2 as they absorb during their life cycle.

  19. Development of the First Gas-Fired Combined Cycle Heat and Power Plant in the Republic of Macedonia

    OpenAIRE

    CINGOSKI, Vlatko

    2002-01-01

    In this paper is talking about: 1. Background of the project 2. First Gas-Fired Combined Cycle Heat and Power Plant in the Republic of Macedonia 3. Basic Plan of the Gas Fired Combined Cycle Heat and Power Plant 4. Implementation plan 5. Required Funds and Financing 6. Environmental Contributions 7. Recommendations and Conclusions

  20. Factors affecting gas migration and contaminant redistribution in heterogeneous porous media subject to electrical resistance heating.

    Science.gov (United States)

    Munholland, Jonah L; Mumford, Kevin G; Kueper, Bernard H

    2016-01-01

    A series of intermediate-scale laboratory experiments were completed in a two-dimensional flow cell to investigate gas production and migration during the application of electrical resistance heating (ERH) for the removal of dense non-aqueous phase liquids (DNAPLs). Experiments consisted of heating water in homogeneous silica sand and heating 270 mL of trichloroethene (TCE) and chloroform (CF) DNAPL pools in heterogeneous silica sands, both under flowing groundwater conditions. Spatial and temporal distributions of temperature were measured using thermocouples and observations of gas production and migration were collected using front-face image capture throughout the experiments. Post-treatment soil samples were collected and analyzed to assess DNAPL removal. Results of experiments performed in homogeneous sand subject to different groundwater flow rates showed that high groundwater velocities can limit subsurface heating rates. In the DNAPL pool experiments, temperatures increased to achieve DNAPL-water co-boiling, creating estimated gas volumes of 131 and 114 L that originated from the TCE and CF pools, respectively. Produced gas migrated vertically, entered a coarse sand lens and subsequently migrated laterally beneath an overlying capillary barrier to outside the heated treatment zone where 31-56% of the original DNAPL condensed back into a DNAPL phase. These findings demonstrate that layered heterogeneity can potentially facilitate the transport of contaminants outside the treatment zone by mobilization and condensation of gas phases during ERH applications. This underscores the need for vapor phase recovery and/or control mechanisms below the water table during application of ERH in heterogeneous porous media during the co-boiling stage, which occurs prior to reaching the boiling point of water. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Effect of nozzle hole size coupling with exhaust gas re-circulation on the engine emission perfomance based on KH-ACT spray model

    Directory of Open Access Journals (Sweden)

    Zhang Liang

    2015-01-01

    Full Text Available To research an effective measure of reducing the Soot and NOx in engine at the same time, different nozzle hole diameters coupled with exhaust gas recirculation (EGR were adopted in this study based on KH-ACT spray breakup model, which takes the aerodynamic-induced ,cavitation-induced and turbulence-induced breakup into account. The SAGE detailed chemistry combustion and the new atomization model used in the simulation have been verified with the experiment data from a YN4100QBZL engine. Different diesel nozzles was adopted in the study combined with different EGR rates ranging from 0% to 40%. The simulation results show that the NOx emission could be reduced effectively for both small(0.1mm and large(0.15mm diesel nozzle when increasing EGR ratio. The soot emission increases for the small nozzle hole size as the EGR increasing. However, when it comes to the large diesel nozzle, the emission increases slightly first and decrease quickly when the EGR rate above 20%.

  2. La catalyse d'épuration des gaz d'échappement automobiles. Situation actuelle et nouvelles orientations Catalytic Automotive Exhaust Gas Depollution. Present Status and New Trends

    Directory of Open Access Journals (Sweden)

    Prigent M.

    2006-11-01

    Full Text Available Cet article passe en revue les différents systèmes catalytiques de post-traitement utilisés actuellement sur la plupart des automobiles pour limiter leurs rejets de polluants. Les systèmes sont différenciés par leur mode de fonctionnement, le type de moteur à dépolluer (deux-temps, quatre-temps, diesel ou essence ou par leur mode de réalisation. Les nouvelles orientations, prévues pour respecter les futures réglementations antipollution, sont également décrites. On montre que certains véhicules prototypes, équipés de moteurs à combustion interne, sont capables d'avoir des émissions très proches de zéro tout comme les véhicules électriques. A review is made of the various types of exhaust gas aftertreatment systems presently used on most vehicles to reduce pollutant emissions. The systems are differentiated by their mode of action, according to the engine type to be depolluted (two-stroke, four-stroke, diesel or spark-ignition, and by their type of make-up. The major developments foreseen in the future, in view of compliance with the new legislations, are described. It is shown that some prototype vehicles with internal combustion engines are able to emit pollutant quantities really close to zero, such as electric cars.

  3. Numerical Study of Compact Plate-Fin Heat Exchanger for Rotary-Vane Gas Refrigeration Machine

    Directory of Open Access Journals (Sweden)

    V. V. Trandafilov

    2017-10-01

    Full Text Available Plate-fin heat exchangers are widely used in refrigeration technique. They are popular because of their compactness and excellent heat transfer performance. Here we present a numerical model for the development, research and optimization of a plate-fin heat exchanger for a rotary-vane gas refrigeration machine. The method of analysis by graphic method of plate - fin heat exchanger is proposed. The model describes the effects of secondary parameters such as axial thermal conductivity through a metal matrix of the heat exchanger. The influence of geometric parameters and heat transfer coefficient is studied. Graphs of dependences of length, efficiency of a fin and pressure drop in a heat exchanger on the thickness of the fin and the number of fins per meter are obtained. To analyze the results of numerical simulation, the heat exchanger was designed in the Aspen HYSYS program. The simulation results show that the total deviation from the proposed numerical model is not more than 15%. 

  4. Novel Self-Heated Gas Sensors Using on-Chip Networked Nanowires with Ultralow Power Consumption.

    Science.gov (United States)

    Tan, Ha Minh; Manh Hung, Chu; Ngoc, Trinh Minh; Nguyen, Hugo; Duc Hoa, Nguyen; Van Duy, Nguyen; Hieu, Nguyen Van

    2017-02-22

    The length of single crystalline nanowires (NWs) offers a perfect pathway for electron transfer, while the small diameter of the NWs hampers thermal losses to tje environment, substrate, and metal electrodes. Therefore, Joule self-heating effect is nearly ideal for operating NW gas sensors at ultralow power consumption, without additional heaters. The realization of the self-heated NW sensors using the "pick and place" approach is complex, hardly reproducible, low yield, and not applicable for mass production. Here, we present the sensing capability of the self-heated networked SnO2 NWs effectively prepared by on-chip growth. Our developed self-heated sensors exhibit a good response of 25.6 to 2.5 ppm NO2 gas, while the response to 500 ppm H2, 100 ppm NH3, 100 ppm H2S, and 500 ppm C2H5OH is very low, indicating the good selectivity of the sensors to NO2 gas. Furthermore, the detection limit is very low, down to 82 parts-per-trillion. As-obtained sensing performance under self-heating mode is nearly identical to that under external heating mode. While the power consumption under self-heating mode is extremely low, around hundreds of microwatts, as scaled-down the size of the electrode is below 10 μm. The selectivity of the sensors can be controlled simply by tuning the loading power that enables simple detection of NO2 in mixed gases. Remarkable performance together with a significantly facile fabrication process of the present sensors enhances the potential application of NW sensors in next generation technologies such as electronic noses, the Internet of Things, and smartphone sensing.

  5. Biomass gasification for CHP with dry gas cleaning and regenerative heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-05-01

    Small scale CHP plants based on biomass gasification technologies are generally expensive and not very efficient due to gas quality problems which increase operation and maintenance cost as well as breakdown. To overcome this situation the team has developed, integrated and tested a complete biomass gasification combine heat and power prototype plant of 250 kWth equipped with a specifically developed dry gas cleaning and heat recovery system. The dry gas cleaning device is a simple dry gas regenerative heat exchanger where tars are stopped by condensation but working at a temperature above due point in order to avoid water condensation. Two types of heat particles separation devices have been tested in parallel multi-cyclone and ceramic filters. After several month spent on modelling design, construction and optimisation, a full test campaign of 400 hours continuous monitoring has been done where all working parameters has been monitored and gas cleaning device performances has been assessed. Results have shown: Inappropriateness of the ceramic filters for the small scale unit due to operation cost and too high sensibility of the filters to the operation conditions fluctuating in a wide range, despite a very high particle separation efficiency 99 %; Rather good efficiency of the multi-cyclone 72% but not sufficient for engine safety. Additional conventional filters where necessary for the finest part; Inappropriateness of the dry gas heat exchanger device for tar removal partly due to a low tar content of the syngas generated, below 100 mg/Nm{sup 3} , but also due to their composition which would have imposed, to be really efficient, a theoretical condensing temperature of 89 C below the water condensation temperature. These results have been confirmed by laboratory tests and modelling. However the tar cracking phase have shown very interesting results and proved the feasibility of thermal cracking with full cleaning of the heat exchanger without further mechanical

  6. Combustion Noise and Pollutants Prediction for Injection Pattern and Exhaust Gas Recirculation Tuning in an Automotive Common-Rail Diesel Engine

    Directory of Open Access Journals (Sweden)

    Arsie Ivan

    2015-01-01

    Full Text Available In the last years, emissions standards for internal combustion engines are becoming more and more restrictive, particularly for NOx and soot emissions from Diesel engines. In order to comply with these requirements, OEMs have to face with innovative combustion concepts and/or sophisticate after-treatment devices. In both cases, the role of the Engine Management System (EMS is increasingly essential, following the large number of actuators and sensors introduced and the need to meet customer expectations on performance and comfort. On the other hand, the large number of control variables to be tuned imposes a massive recourse to the experimental testing which is poorly sustainable in terms of time and money. In order to reduce the experimental effort and the time to market, the application of simulation models for EMS calibration has become fundamental. Predictive models, validated against a limited amount of experimental data, allow performing detailed analysis on the influence of engine control variables on pollutants, comfort and performance. In this paper, a simulation analysis on the impact of injection pattern and Exhaust Gas Recirculation (EGR rate on fuel consumption, combustion noise, NO and soot emissions is presented for an automotive Common-Rail Diesel engine. Simulations are accomplished by means of a quasi-dimensional multi-zone model of in-cylinder processes. Furthermore a methodology for in-cylinder pressure processing is presented to estimate combustion noise contribution to radiated noise. Model validation is carried out by comparing simulated in-cylinder pressure traces and exhaust emissions with experimental data measured at the test bench in steady-state conditions. Effects of control variables on engine performance, noise and pollutants are analyzed by imposing significant deviation of EGR rate and injection pattern (i.e. rail pressure, start-of-injection, number of injections. The results evidence that quasi-dimensional in

  7. Flow structure and heat exchange analysis in internal cooling channel of gas turbine blade

    Science.gov (United States)

    Szwaba, Ryszard; Kaczynski, Piotr; Doerffer, Piotr; Telega, Janusz

    2016-08-01

    This paper presents the study of the flow structure and heat transfer, and also their correlations on the four walls of a radial cooling passage model of a gas turbine blade. The investigations focus on heat transfer and aerodynamic measurements in the channel, which is an accurate representation of the configuration used in aeroengines. Correlations for the heat transfer coefficient and the pressure drop used in the design of radial cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include corner fillet, ribs with fillet radii and special orientation. Therefore, this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which possesses very realistic features.

  8. Influence of internal channel geometry of gas turbine blade on flow structure and heat transfer

    Science.gov (United States)

    Szwaba, Ryszard; Kaczynski, Piotr; Telega, Janusz; Doerffer, Piotr

    2017-12-01

    This paper presents the study of the influence of channel geometry on the flow structure and heat transfer, and also their correlations on all the walls of a radial cooling passage model of a gas turbine blade. The investigations focus on the heat transfer and aerodynamic measurements in the channel, which is an accurate representation of the configuration used in aeroengines. Correlations for the heat transfer coefficient and the pressure drop used in the design of internal cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include a corner fillets, ribs with fillet radii and a special orientation. Therefore, this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which has very realistic features.

  9. Potential for natural gas based CHP generation in Swedish district heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Knutsson, David; Werner, Sven [Chalmers Univ. of Tech., Goeteborg (Sweden). Div. of Energy Systems Technology

    2002-07-01

    Sweden has the second lowest carbon dioxide emissions per capita in the European Union, 28% below the EU average. The major explanation for this fact is the dominating resources of hydropower and nuclear power in the Swedish power generation. As the deregulation of the European electricity markets will continue, the electricity systems inside the Union will become more integrated. Hence, Sweden is merging into a carbon rich power generation system. Currently, the Swedish district heating sector has a very low national power-to-heat-ratio, which implicates that Sweden has great potential for additional electricity production in the existing district heating systems. This paper shows, that if the extension of the natural gas grid proposed in the Nordic Gas Grid project is realised, the annual potential for further natural gas based electricity production in the Swedish district heating systems is 26 TWh. In the short range, the corresponding carbon dioxide reduction in northern Europe is 16 M ton. This is approximately one quarter of the total annual carbon dioxide emissions in Sweden today.

  10. Investigation of Freeze and Thaw Cycles of a Gas-Charged Heat Pipe

    Science.gov (United States)

    Ku, Jentung; Ottenstein, Laura; Krimchansky, Alexander

    2012-01-01

    The traditional constant conductance heat pipes (CCHPs) currently used on most spacecraft run the risk of bursting the pipe when the working fluid is frozen and later thawed. One method to avoid pipe bursting is to use a gas-charged heat pipe (GCHP) that can sustain repeated freeze/thaw cycles. The construction of the GCHP is similar to that of the traditional CCHP except that a small amount of non-condensable gas (NCG) is introduced and a small length is added to the CCHP condenser to serve as the NCG reservoir. During the normal operation, the NCG is mostly confined to the reservoir, and the GCHP functions as a passive variable conductance heat pipe (VCHP). When the liquid begins to freeze in the condenser section, the NCG will expand to fill the central core of the heat pipe, and ice will be formed only in the grooves located on the inner surface of the heat pipe in a controlled fashion. The ice will not bridge the diameter of the heat pipe, thus avoiding the risk of pipe bursting during freeze/thaw cycles. A GCHP using ammonia as the working fluid was fabricated and then tested inside a thermal vacuum chamber. The GCHP demonstrated a heat transport capability of more than 200W at 298K as designed. Twenty-seven freeze/thaw cycles were conducted under various conditions where the evaporator temperature ranged from 163K to 253K and the condenser/reservoir temperatures ranged from 123K to 173K. In all tests, the GCHP restarted without any problem with heat loads between 10W and 100W. No performance degradation was noticed after 27 freeze/thaw cycles. The ability of the GCHP to sustain repeated freeze/thaw cycles was thus successfully demonstrated.

  11. Analyzing the Performance of a Dual Loop Organic Rankine Cycle System for Waste Heat Recovery of a Heavy-Duty Compressed Natural Gas Engine

    Directory of Open Access Journals (Sweden)

    Baofeng Yao

    2014-11-01

    Full Text Available A dual loop organic Rankine cycle (DORC system is designed to recover waste heat from a heavy-duty compressed natural gas engine (CNGE, and the performance of the DORC–CNGE combined system is simulated and discussed. The DORC system includes high-temperature (HT and low-temperature (LT cycles. The HT cycle recovers energy from the exhaust gas emitted by the engine, whereas the LT cycle recovers energy from intake air, engine coolant, and the HT cycle working fluid in the preheater. The mathematical model of the system is established based on the first and second laws of thermodynamics. The characteristics of waste heat energy from the CNGE are calculated according to engine test data under various operating conditions. Moreover, the performance of the DORC–CNGE combined system is simulated and analyzed using R245fa as the working fluid. Results show that the maximum net power output and the maximum thermal efficiency of the DORC system are 29.37 kW and 10.81%, respectively, under the rated power output condition of the engine. Compared with the original CNG engine, the maximum power output increase ratio and the maximum brake specific fuel consumption improvement ratio are 33.73% and 25%, respectively, in the DORC–CNGE combined system.

  12. Case study on natural gas application for district heating and cooling in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Maues, Jair Arone [Pontificia Universidade Catolica do Rio de Janeiro (IE/PUC-Rio), Rio de Janeiro, RJ (Brazil). Inst. de Energia; Akiyama, Junichi [Mitsui Gas e Energia do Brasil Ltda., Rio de janeiro, RJ (Brazil)

    2012-07-01

    The distributed cogeneration applying natural gas consists in an excellent alternative to use this source, but it is limited by a compatible heat demand that must be found in its application. District heating and cooling solutions can overcome this hurdle, especially in Brazil, a tropical country, where new industrial and commercial enterprises usually install central air conditioning systems. By 2020 natural gas demand shall reach a value of more than 200 MM m{sup 3} per day, accordingly to the Brazilian Energy Research Office (EPE, 2011). An expressive part of it could be consumed in cogeneration systems like the one described in this paper. This project had a special taxes exception rule applied. The chilled water and heated thermal oil produced were not taxed at all. But these two DHC utilities could obtain a different treatment if someone considers this is a tricky way of power and heat trading, which should be taxed as electricity and natural gas normally are. A bolder legislation with respect to the export of energy surplus would facilitate the project and operation of this kind of system, because the basic premise would be to attend the thermal demand with the electrical power installed, maximizing the global efficiency of the installation. An average 8 GW of Brazilian power demand, with roughly 50 MMm{sup 3}/day of natural gas consumption, could be attended by distributed energy gas cogeneration enterprises. If this prediction were totally accomplished it would bring the Brazilian participation of distributed energy in total power generation to values close to 10% in 2020, value already reached in average by the world biggest electricity's consumer countries (WADE, 2006). This also would mean an equivalent investment economy of approximately 11,000 MW in transmission and distribution lines capacity (author)

  13. Sabots, Obturator and Gas-In-Launch Tube Techniques for Heat Flux Models in Ballistic Ranges

    Science.gov (United States)

    Bogdanoff, David W.; Wilder, Michael C.

    2013-01-01

    For thermal protection system (heat shield) design for space vehicle entry into earth and other planetary atmospheres, it is essential to know the augmentation of the heat flux due to vehicle surface roughness. At the NASA Ames Hypervelocity Free Flight Aerodynamic Facility (HFFAF) ballistic range, a campaign of heat flux studies on rough models, using infrared camera techniques, has been initiated. Several phenomena can interfere with obtaining good heat flux data when using this measuring technique. These include leakage of the hot drive gas in the gun barrel through joints in the sabot (model carrier) to create spurious thermal imprints on the model forebody, deposition of sabot material on the model forebody, thereby changing the thermal properties of the model surface and unknown in-barrel heating of the model. This report presents developments in launch techniques to greatly reduce or eliminate these problems. The techniques include the use of obturator cups behind the launch package, enclosed versus open front sabot designs and the use of hydrogen gas in the launch tube. Attention also had to be paid to the problem of the obturator drafting behind the model and impacting the model. Of the techniques presented, the obturator cups and hydrogen in the launch tube were successful when properly implemented

  14. HEAT PUMP GAS COOLER CONTROL USING CRITERION OF MINIMUM OF EXERGY LOSSSES

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2014-08-01

    Full Text Available This paper focuses on the development of the criterion of optimality of transients of the control system, based on the minimum of exergy losses in the gas cooler of carbon dioxide heat pump. It is noted that the exergy quality criterion has a clear physical meaning, as compared with the integral quadratic criterion in which the choice of the coefficients in the integrand is not justified. Mathematic model of heat exchanger is obtained using the method of solving differential equations, without going to the irrational transfer functions. The model is reduced to transfer functions of the first and second order with the delay. The continuous temperature control system of heat pump gas cooler is considered. It is shown, that one of the versions of the control system for the minimization of the proposed criterion can be a combined control system using both the principle of the negative feedback and the principle of the invariance related to a number of disturbances affecting the processes of heat transfer in the heat exchanger.

  15. Exergoeconomic optimization of an ammonia–water hybrid absorption–compression heat pump for heat supply in a spraydrying facility

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Markussen, Wiebke Brix; Reinholdt, Lars

    2015-01-01

    load of 6.1 MW. The exhaust air from the drying process is 80 C. The implementation of anammonia–water hybrid absorption–compression heat pump to partly cover the heat load is investigated. A thermodynamic analysis is applied to determine optimal circulation ratios for a number of ammonia mass......Spray-drying facilities are among the most energy intensive industrial processes. Using a heat pump to recover waste heat and replace gas combustion has the potential to attain both economic and emissions savings. In the case examined a drying gas of ambient air is heated to 200 C yielding a heat...

  16. Exergoeconomic optimization of an ammonia-water hybrid heat pump for heat supply in a spray drying facility

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Markussen, Wiebke Brix; Reinholdt, Lars

    2014-01-01

    rate is 100,000 m3/h which yields a heat load of 6.1 MW. The exhaust air from the drying process is 80 XC. The implementation of an ammonia-water hybrid absorption-compression heat pump to partly cover the heat load is investigated. A thermodynamic analysis is applied to determine optimal circulation......Spray drying facilities are among the most energy intensive industrial processes. Using a heat pump to recover waste heat and replace gas combustion has the potential to attain both economic and emissions savings. In the case examined a drying gas of ambient air is heated to 200 XC. The inlet flow...

  17. Is the gas hydrate film growth controlled by intrinsic kinetic or heat transfer?

    Energy Technology Data Exchange (ETDEWEB)

    Peng, B.Z.; Chen, G.J.; Sun, C.Y.; Yang, L.Y.; Luo, H. [China Univ. of Petroleum, Beijing (China). State Key Laboratory of Heavy Oil Processing

    2008-07-01

    Gas hydrates are non-stoichiometric crystalline inclusion compounds. They are composed of water molecules encaging guest gas molecules like natural gas components. When water contacts with a hydrate former in liquid or a gas state under suitable temperature and pressure conditions, hydrates usually form and grow in the form of a film at the interface between the two fluid phases. The growth behavior of this type of film is of significant importance with respect to the various components of hydrate production, such as the storage and transportation of natural gas and desalination. However, questions remain regarding the control steps of hydrate film growth. This paper discussed a study that systematically measured the lateral growth rates of methane (CH{sub 4}) and carbon dioxide (CO{sub 2}) hydrates film by suspending individual gas bubbles in water. In order to determine the correlation between the hydrate film growth rate and the driving force, modeling of hydrate film growth by intrinsic kinetics and heat transfer was conducted. The temperature difference between the moving hydrate film front and the bulk water was calculated to evaluate the contribution of heat transfer to hydrate film growth rate. The paper discussed the experiment, with reference to the equipment and material; experimental procedure; and data processing. A simulation of the hydrate film growth revealed that heat transfer had little contribution to hydrate film growth, and the intrinsic kinetic was the main control step for CH{sub 4} and CO{sub 2} hydrate film growth. 16 refs., 2 tabs., 5 figs.

  18. Initiation of long, free-standing Z-discharges by CO2 laser gas heating

    Energy Technology Data Exchange (ETDEWEB)

    Nieman, C.; Tauschwitz, A.; Penache, D.; Neff, S.; Knobloch, R.; Birkner, R.; Presura, R.; Hoffmann, D.H.H.; Yu, S.S.; Sharp, W.M.

    2004-04-19

    High current discharge channels can neutralize both current and space charge of very intense ion beams. Therefore they are considered as an interesting alternative for the final focus and beam transport in a heavy ion beam fusion reactor. At the GSI accelerator facility, 50 cm long, stable, free-standing discharge channels with currents in excess of 40 kA in 2 to 25 mbar ammonia (NH{sub 3}) gas are investigated for heavy ion beam transport studies. The discharges are initiated by a CO{sub 2} laser pulse along the channel axis before the discharge is triggered. Resonant absorption of the laser, tuned to the {nu}{sub 2} vibration of the ammonia molecule, causes strong gas heating. Subsequent expansion and rarefaction of the gas prepare the conditions for a stable discharge to fulfill the requirements for ion beam transport. This paper describes the laser-gas interaction and the discharge initiation mechanism. We report on the channel stability and evolution, measured by fast shutter and streak imaging techniques. The rarefaction of the laser heated gas is studied by means of a hydrocode simulation.

  19. Special considerations on operating a fuel cell power plant using natural gas with marginal heating value

    Energy Technology Data Exchange (ETDEWEB)

    Moses, L. Ng; Chien-Liang Lin [Industrial Technology Research Institute, Taiwan (China); Ya-Tang Cheng [Power Research Institute, Taiwan (China)

    1996-12-31

    In realizing new power generation technologies in Taiwan, a phosphoric acid fuel cell power plant (model PC2513, ONSI Corporation) has been installed in the premises of the Power Research Institute of the Taiwan Power Company in Taipei County of Taiwan. The pipeline gas supplying to the site of this power plant has a high percentage of carbon dioxide and thus a slightly lower heating value than that specified by the manufacturer. Because of the lowering of heating value of input gas, the highest Output power from the power plant is understandably less than the rated power of 200 kW designed. Further, the transient response of the power plant as interrupted from the Grid is also affected. Since this gas is also the pipeline gas supplying to the heavily populated Taipei Municipal area, it is conceivable that the success of the operations of fuel cells using this fuel is of vital importance to the promotion of the use of this power generation technology in Taiwan. Hence, experiments were set up to assess the feasibility of this fuel cell power plant using the existing pipeline gas in this part of Taiwan where fuel cells would most likely find useful.

  20. Initiation of long, free-standing z discharges by CO2 laser gas heating

    Science.gov (United States)

    Niemann, C.; Tauschwitz, A.; Penache, D.; Neff, S.; Knobloch, R.; Birkner, R.; Presura, R.; Hoffmann, D. H. H.; Yu, S. S.; Sharp, W. M.

    2002-01-01

    High current discharge channels can neutralize both current and space charge of very intense ion beams. Therefore, they are considered an interesting solution for final focus and beam transport in a heavy ion beam fusion reactor. At the Gesellschaft für Schwerionenforschung accelerator facility, 50 cm long, free-standing discharge channels were created in a 60 cm diameter metallic chamber. Discharges with currents of 45 kA in 2 to 25 mbar ammonia (NH3) gas are initiated by a CO2 laser pulse along the channel axis before the capacitor bank is triggered. Resonant absorption of the laser, tuned to the v2 vibration of the ammonia molecule, causes strong gas heating. Subsequent expansion and rarefaction of the gas prepare the conditions for a stable discharge to fulfill the requirements for ion beam transport. The influence of an electric prepulse on the high current discharge was investigated. This article describes the laser-gas interaction and the discharge initiation mechanism. We found that channels are magnetohydrodynamic stable up to currents of 45 kA, measured by fast shutter and streak imaging techniques. The rarefaction of the laser heated gas is studied by means of a one-dimensional Lagrangian fluid code (CYCLOPS) and is identified as the dominant initiation mechanism of the discharge.

  1. Opportunities for direct-contact waste heat recuperators for industrial heat recovery

    Science.gov (United States)

    Richlen, S. L.; Semler, T. T.

    The potential industrial applications of the direct-contact waste heat recuperator (DCWHR) for the 353 K to 672 K temperature range were identified. The DCWHR increases the heat transfer area per unit volume over typical heat exchangers, and holds promise for latent heat recovery from waste streams. Results show that, for selected industrial waste heat sources, the production of hot process water by direct-contact heat exchange can be economically accomplished for waste heat (hot gas) streams at 478 K to 672 K with greater than 4.72 cu m/sec exhaust. Additionally, a DCWHR is particularly recommended for particulate-laden exhaust streams where scrubbing is already required by environmental consideration; the recovered heat becomes a factor in reducing the negative cash flow attributable to the use of scrubbing equipment. Incentives and obstacles to early market penetration of the technology are recognized.

  2. The determination of regulated and some unregulated exhaust gas components from ethanol blended diesel fuels in comparison with neat diesel and ethanol fuel

    Energy Technology Data Exchange (ETDEWEB)

    Haupt, D.; Nordstroem, F.; Niva, M.; Bergenudd, L.; Hellberg, S. [Luleaa Univ. of Technology (Sweden)

    1999-02-01

    Investigations that have been carried out at Luleaa University of Technology (LTU) show how exhaust gas emissions and engine performance are affected by the composition of the fuels. The fuels that have been tested and compared are two different ethanol blended diesel fuels, `neat` diesel fuels and neat ethanol fuels. Two different, heavy-duty engines were used for the investigations; one for the neat ethanol fuels and the other for the ethanol blended diesel fuels and neat diesel fuels. The investigation also includes some tests with two oxidizing catalysts. Results from the investigation show that none of the fuels produce emissions exceeding the values of the 13-mode test (ECE R-49, 1997). Lowest HC-emission levels were found for the two `neat` ethanol fuels although the difference between the HC-emissions can be considered negligible for the studied fuels. An effective reduction in the hydrocarbon emissions was achieved by using a catalyst. The investigation also shows that the NO{sub x} emissions were much lower for the neat ethanol fuels than for the other fuels. Even if the CO emissions from the two ethanol fuels were approximately three times higher than for the other investigated fuels the use of a catalyst equalize the CO emissions from the studied fuels. The formaldehyde and acetaldehyde emissions were clearly higher for the neat ethanol fuels than for the other investigated fuels. However, by using a catalyst the formaldehyde emission from the ethanol fuels could be decreased. Unfortunately, the use of a catalyst also resulted in an increase in the emission of acetaldehyde from the ethanol fuelled engine 10 refs, 11 figs, 5 tabs, 6 appendixes

  3. Heat and mass transfer rates during flow of dissociated hydrogen gas over graphite surface

    Science.gov (United States)

    Nema, V. K.; Sharma, O. P.

    1986-01-01

    To improve upon the performance of chemical rockets, the nuclear reactor has been applied to a rocket propulsion system using hydrogen gas as working fluid and a graphite-composite forming a part of the structure. Under the boundary layer approximation, theoretical predictions of skin friction coefficient, surface heat transfer rate and surface regression rate have been made for laminar/turbulent dissociated hydrogen gas flowing over a flat graphite surface. The external stream is assumed to be frozen. The analysis is restricted to Mach numbers low enough to deal with the situation of only surface-reaction between hydrogen and graphite. Empirical correlations of displacement thickness, local skin friction coefficient, local Nusselt number and local non-dimensional heat transfer rate have been obtained. The magnitude of the surface regression rate is found low enough to ensure the use of graphite as a linear or a component of the system over an extended period without loss of performance.

  4. Decay Heat Removal in GEN IV Gas-Cooled Fast Reactors

    Directory of Open Access Journals (Sweden)

    Lap-Yan Cheng

    2009-01-01

    Full Text Available The safety goal of the current designs of advanced high-temperature thermal gas-cooled reactors (HTRs is that no core meltdown would occur in a depressurization event with a combination of concurrent safety system failures. This study focused on the analysis of passive decay heat removal (DHR in a GEN IV direct-cycle gas-cooled fast reactor (GFR which is based on the technology developments of the HTRs. Given the different criteria and design characteristics of the GFR, an approach different from that taken for the HTRs for passive DHR would have to be explored. Different design options based on maintaining core flow were evaluated by performing transient analysis of a depressurization accident using the system code RELAP5-3D. The study also reviewed the conceptual design of autonomous systems for shutdown decay heat removal and recommends that future work in this area should be focused on the potential for Brayton cycle DHRs.

  5. Advanced Exploration Systems Logistics Reduction and Repurposing Trash-to-Gas and Heat Melt Compactor KSC

    Science.gov (United States)

    Caraccio, Anne J.; Layne, Andrew; Hummerick, Mary

    2013-01-01

    Topics covered: 1. Project Structure 2. "Trash to Gas" 3. "Smashing Trash! The Heat Melt Compactor" 4. "Heat Melt Compaction as an Effective Treatment for Eliminating Microorganisms from Solid Waste" Thermal degradation of trash reduces volume while creating water, carbon dioxide and ash. CO2 can be fed to Sabatier reactor for CH4 production to fuel LOX/LCH4 ascent vehicle. Optimal performance: HFWS, full temperature ramp to 500-600 C. Tar challenges exist. Catalysis: Dolomag did eliminate allene byproducts from the product stream. 2nd Gen Reactor Studies. Targeting power, mass, time efficiency. Gas separation, Catalysis to reduce tar formation. Microgravity effects. Downselect in August will determine where we should spend time optimizing the technology.

  6. Industrial gas and fuel oil heating technology - modular construction; Gas- und Oel-Industriefeuerungstechnik - Blockbauweise

    Energy Technology Data Exchange (ETDEWEB)

    Hauswirth, M. [OERTLI Induflame AG, Schwerzenbach (Switzerland)

    1999-06-01

    Dealing with change is also turning into a core competence in heating technology. Whenever a new industrial heating product has been launched anywhere in the world, all the competitors will be in the know after only a brief spell. There are hardly any technological leads that have not been caught up with or even overtaken within the space of a year. In the face of products of increasing similarity, the determination of actual customer requirements will increasingly be decided on the basis of factors such as price, speed, service and quality, but also creativity and innovation. (orig.) [Deutsch] Der Umgang mit dem Wandel wird auch in der Feuerungstechnik zur Kernkompetenz werden. Wird irgendwo auf der Welt ein neues Industriefeuerungs-Produkt lanciert, so wissen dies heute alle Mitbewerber bereits nach kurzer Zeit. Es gibt kaum noch technologische Vorspruenge, die nicht bereits nach einem Jahr wieder ein- bzw. ueberholt sind. Angesichts immer aehnlicher werdender Produkte sind bei der Abklaerung effektiver Kundenbeduerfnisse in zunehmendem Masse Faktoren wie Preis, Tempo, Dienstleistung und Qualitaet, aber auch Kreativitaet und Innovation entscheidend. (orig.)

  7. Simulation of Heat Transfer to the Gas Coolant with Low Prandtl Number Value

    Directory of Open Access Journals (Sweden)

    T. N. Kulikova

    2015-01-01

    Full Text Available The work concerns the simulating peculiarities of heat transfer to the gas coolants with low values of the Prandtl number, in particular, to the binary mixtures of inert gases.The paper presents simulation results of heat transfer to the fully established flow of a helium-xenon mixture in the round tube of 6 mm in diameter with the boundary condition of the second kind. It considers a flow of three helium-xenon mixtures with different helium content and molecular Prandtl numbers within the range 0.239–0.322 and with Reynolds numbers ranged from 10000 to 50000. During numerical simulation a temperature factor changed from 1.034 to 1.061. CFD-code STAR-CCM+ that is designed for solving a wide range of problems of hydrodynamics, heat transfer and stress was used as the primary software.The applicability of the five models for the turbulent Prandtl number is examined. It is shown that the choice of the model has a significant influence on the heat transfer coefficient. The paper presents structural characteristics of the flow in the wall region. It estimates a thermal stabilization section to be approximately as long as 30 diameters of tube.Simulation results are compared with the known data on heat transfer to gas coolants with low values of the Prandtl number. It is shown that V2F low-Reynolds number -ε turbulence model with an approximation for the turbulent Prandtl number used according Kays-CrawfordWeigand gives the best compliance with the results predicted by relationships of Kays W.M. and Petukhov B.S. The approximating correlation summarizes a set of simulation results.Application of the work results is reasonable when conducting the numerical simulation of heat transfer to binary gas mixtures in channels of different forms. The presented approximating correlation allows rapid estimate of heat transfer coefficients to the gas coolants with a low value of the molecular Prandl number within the investigated range with a flow through the

  8. HRSGs for gas turbine applications

    Energy Technology Data Exchange (ETDEWEB)

    Ganapathy, V.

    1987-08-01

    Waste heat recovery plays a dominant role in power and process plants. Heat Recovery Steam Generators (HRSGs) are widely used to recover energy from waste gas streams either because of process considerations or for economic reasons. HRSGs in sulfuric acid and hydrogen plants are examples of the former, while HRSGs in gas turbine installations and in incineration plants are examples of the latter. This article outlines the features of HRSGs for gas turbine exhaust, which will be of interest to plant engineers and consultants.

  9. Heat transfer characteristics of a non-boiling pool with spatially uniform gas injection. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Ganguli, A.; Luk, A.; Bankoff, S.G.

    1978-12-01

    It is possible to encounter molten fuel pools in the course of events during a hypothetical Liquid Metal Fast Breeder Reactor accident. In such cases it may be important to estimate correctly the rate of melting of the pool walls and bottom, which are governed by the rate of heat transfer to those materials. The heat transfer characteristics of internally heated two-phase pools are thus of interest. Heat transfer measurements were made in the horizontal and downward directions both in transient and in steady state. The transient study involved slow cooling or heating of the pool liquid, while in the steady state case heat was provided by electrical immersion heaters. A permanent gas was injected from a distributed hypodermic tubing network with two hole sizes. Void fraction measurements were also made by static pressure probes. The data is reported as plots of Nusselts number versus Reynolds number and surface evaporation and entrainment effects for a boiling pool were estimated for comparison purposes.

  10. Integration of a molten carbonate fuel cell with a direct exhaust absorption chiller

    Science.gov (United States)

    Margalef, Pere; Samuelsen, Scott

    A high market value exists for an integrated high-temperature fuel cell-absorption chiller product throughout the world. While high-temperature, molten carbonate fuel cells are being commercially deployed with combined heat and power (CHP) and absorption chillers are being commercially deployed with heat engines, the energy efficiency and environmental attributes of an integrated high-temperature fuel cell-absorption chiller product are singularly attractive for the emerging distributed generation (DG) combined cooling, heating, and power (CCHP) market. This study addresses the potential of cooling production by recovering and porting the thermal energy from the exhaust gas of a high-temperature fuel cell (HTFC) to a thermally activated absorption chiller. To assess the practical opportunity of serving an early DG-CCHP market, a commercially available direct fired double-effect absorption chiller is selected that closely matches the exhaust flow and temperature of a commercially available HTFC. Both components are individually modeled, and the models are then coupled to evaluate the potential of a DG-CCHP system. Simulation results show that a commercial molten carbonate fuel cell generating 300 kW of electricity can be effectively coupled with a commercial 40 refrigeration ton (RT) absorption chiller. While the match between the two "off the shelf" units is close and the simulation results are encouraging, the match is not ideal. In particular, the fuel cell exhaust gas temperature is higher than the inlet temperature specified for the chiller and the exhaust flow rate is not sufficient to achieve the potential heat recovery within the chiller heat exchanger. To address these challenges, the study evaluates two strategies: (1) blending the fuel cell exhaust gas with ambient air, and (2) mixing the fuel cell exhaust gases with a fraction of the chiller exhaust gas. Both cases are shown to be viable and result in a temperature drop and flow rate increase of the

  11. Progress towards understanding and predicting heat transfer in the turbine gas path

    Science.gov (United States)

    Simoneau, Robert J.; Simon, Frederick F.

    1993-01-01

    A new era is dawning in the ability to predict convection heat transfer in the turbine gas path. We feel that the technical community now has the capability to mount a major assault on this problem, which has eluded significant progress for a long time. In this paper we hope to make a case for this bold statement by reviewing the state of the art in three major and related areas, which we believe are indispensable to the understanding and accurate prediction of turbine gas path heat transfer: configuration-specific experiments, fundamental physics and model development, and code development. We begin our review with the configuration-specific experiments, whose data have provided the big picture and guided both the fundamental modeling research and the code development. Following that, we examine key modeling efforts and comment on what will be needed to incorporate them into the codes. In this region we concentrate on bypass transition, 3D endwalls, and film cooling. We then review progress and directions in the development of computer codes to predict turbine gas path heat transfer. Finally, we cite examples and make observations on the more recent efforts to do all this work in a simultaneous, interactive, and more synergistic manner. We conclude with an assessment of progress, suggestions for how to use the current state of the art, and recommendations for the future.

  12. Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corp. , Columbus, Ohio. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-11-01

    The Solar Energy System located at the Columbia Gas Corporation, Columbus, Ohio, has 2978 ft/sup 2/ of Honeywell single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/h Bryan water-tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton Arkla hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts are included from the site files, specification references, drawings, installation, operation and maintenance instructions.

  13. Mathematical Simulation of Convective Heat Transfer in the Low-Temperature Storage of Liquefied Natural Gas

    Directory of Open Access Journals (Sweden)

    Shestakov Igor A.

    2015-01-01

    Full Text Available The article shows the results of mathematical modeling of convective heat transfer in the low-temperature storage of liquefied natural gas. Regime of natural convection in an enclosure with different intensity of the heat flux at the external borders are investigated. Was examined two-dimensional nonstationary problem within the model of Navier-Stokes in dimensionless variables “vorticity - stream function - temperature”. Distributions of hydrodynamic parameters and temperatures that characterize the basic regularities of the processes are obtained. Circulating flows are determined and carried out the analysis of vortices formation mechanism and the temperature distribution in solution at conditions of natural convection when the Grashof number (Gr = 106. A significant influence of heat transfer rate on solutions boundary on flow structure and temperature field in LNG storage tanks.

  14. Gas chromatographic analysis of volatile sulfur compounds from heated milk using static headspace sampling.

    Science.gov (United States)

    Christensen, K R; Reineccius, G A

    1992-08-01

    An investigation was conducted to test the feasibility of using gas chromatography with static headspace sampling as an objective tool to measure milk flavor quality. Heated milk off-flavor was chosen for study. Different strategies were tried for increasing the sensitivity of a commercially available headspace method, including salting out with sodium sulfate, cryofocusing during injection, and applying backpressure to the sampling loop. With the aid of a sulfur-specific detector, the resulting system was sufficiently sensitive to detect the sulfur volatiles, H2S and dimethyl sulfide, at the concentrations found in pasteurized skim milk. Milk that was heated to varying degrees was analyzed, and the analytical results were compared with the intensity of heated flavor as determined by a sensory panel. For skim milk, correlations were moderately strong: Spearman's correlation coefficients for H2S and dimethyl sulfide were .75 and .60, respectively. Correlations were weak for whole milk.

  15. Laboratory Performance Evaluation of Residential Scale Gas Engine Driven Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Heiba, Ahmad [ORNL; Mehdizadeh Momen, Ayyoub [ORNL; Mahderekal, Dr. Isaac [Intellichoice Energy, Boulder City, Nevada

    2016-01-01

    Building space cooling is, and until 2040 is expected to continue to be, the single largest use of electricity in the residential sector in the United States (EIA Energy Outlook 2015 .) Increases in electric-grid peak demand leads to higher electricity prices, system inefficiencies, power quality problems, and even failures. Thermally-activated systems, such as gas engine-driven heat pump (GHP), can reduce peak demand. This study describes the performance of a residential scale GHP. It was developed as part of a cooperative research and development agreement (CRADA) that was authorized by the Department of Energy (DOE) between OAK Ridge National Laboratory (ORNL) and Southwest Gas. Results showed the GHP produced 16.5 kW (4.7 RT) of cooling capacity at 35 C (95 F) rating condition with gas coefficient of performance (COP) of 0.99. In heating, the GHP produced 20.2 kW (5.75 RT) with a gas COP of 1.33. The study also discusses other benefits and challenges facing the GHP technology such as cost, reliability, and noise.

  16. Similarity solution for the flow behind a shock wave in a non-ideal gas with heat conduction and radiation heat-flux in magnetogasdynamics

    Science.gov (United States)

    Nath, G.; Vishwakarma, J. P.

    2014-05-01

    The propagation of a spherical (or cylindrical) shock wave in a non-ideal gas with heat conduction and radiation heat-flux, in the presence of a spacially decreasing azimuthal magnetic field, driven out by a moving piston is investigated. The heat conduction is expressed in terms of Fourier's law and the radiation is considered to be of the diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient αR are assumed to vary with temperature and density. The gas is assumed to have infinite electrical conductivity and to obey a simplified van der Waals equation of state. The shock wave moves with variable velocity and the total energy of the wave is non-constant. Similarity solutions are obtained for the flow-field behind the shock and the effects of variation of the heat transfer parameters, the parameter of the non-idealness of the gas, both, decreases the compressibility of the gas and hence there is a decrease in the shock strength. Further, it is investigated that with an increase in the parameters of radiative and conductive heat transfer the tendency of formation of maxima in the distributions of heat flux, density and isothermal speed of sound decreases. The pressure and density vanish at the inner surface (piston) and hence a vacuum is form at the center of symmetry. The shock waves in conducting non-ideal gas with conductive and radiative heat fluxes can be important for description of shocks in supernova explosions, in the study of central part of star burst galaxies, nuclear explosion, chemical detonation, rupture of a pressurized vessels, in the analysis of data from exploding wire experiments, and cylindrically symmetric hypersonic flow problems associated with meteors or reentry vehicles, etc. The findings of the present works provided a clear picture of whether and how the non-idealness parameter, conductive and radiative heat transfer parameters and the magnetic field affect the flow behind the shock

  17. The Effect of Inclination Angle on Critical Heat Flux in a Locally Heated Liquid Film Moving Under the Action of Gas Flow in a Mini-Channel

    Directory of Open Access Journals (Sweden)

    Tkachenko Egor M.

    2016-01-01

    Full Text Available Intensively evaporating liquid films moving under the action of the cocurrent gas flow in a microchannel are promising for the use in modern cooling systems of semiconductor devices with high local heat release. This work has studied the dependence of the critical heat flux on the inclination angle of the channel. It has been found that the inclination angle in the plane parallel to the flow has no significant effect on the critical heat flux. Whereas the inclination angle in the plane perpendicular to the flow, on the contrary, significantly changes the value of the critical heat flux. However, for a given flow rate of fluid there is a threshold gas velocity at which the critical heat flux does not differ from the case of zero inclination of the channel. Thus, it can be concluded that the cooling system based on shear-driven liquid films can be potentially used when direction of the gravity changes.

  18. Intelligent Integration between Human Simulated Intelligence and Expert Control Technology for the Combustion Process of Gas Heating Furnace

    Directory of Open Access Journals (Sweden)

    Yucheng Liu

    2014-01-01

    Full Text Available Due to being poor in control quality of the combustion process of gas heating furnace, this paper explored a sort of strong robust control algorithm in order to improve the control quality of the combustion process of gas heating furnace. The paper analyzed the control puzzle in the complex combustion process of gas heating furnace, summarized the cybernetics characteristic of the complex combustion process, researched into control strategy of the uncertainty complex control process, discussed the control model of the complex process, presented a sort of intelligent integration between human-simulated intelligence and expert control technology, and constructed the control algorithm for the combustion process controlling of gas heating furnace. The simulation results showed that the control algorithm proposed in the paper is not only better in dynamic and steady quality of the combustion process, but also obvious in energy saving effect, feasible, and effective in control strategy.

  19. Improvement of the thermal and mechanical flow characteristics in the exhaust system of piston engine through the use of ejection effect

    Science.gov (United States)

    Plotnikov, L. V.; Zhilkin, B. P.; Brodov, Yu M.

    2017-11-01

    The results of experimental research of gas dynamics and heat transfer in the exhaust process in piston internal combustion engines are presented. Studies were conducted on full-scale models of piston engine in the conditions of unsteady gas-dynamic (pulsating flows). Dependences of the instantaneous flow speed and the local heat transfer coefficient from the crankshaft rotation angle in the exhaust pipe are presented in the article. Also, the flow characteristics of the exhaust gases through the exhaust systems of various configurations are analyzed. It is shown that installation of the ejector in the exhaust system lead to a stabilization of the flow and allows to improve cleaning of the cylinder from exhaust gases and to optimize the thermal state of the exhaust pipes. Experimental studies were complemented by numerical simulation of the working process of the DM-21 diesel engine (production of “Ural diesel-motor plant”). The object of modeling was the eight-cylinder diesel with turbocharger. The simulation was performed taking into account the processes nonstationarity in the intake and exhaust pipes for the various configurations of exhaust systems (with and without ejector). Numerical simulation of the working process of diesel was performed in ACTUS software (ABB Turbo Systems). The simulation results confirmed the stabilization of the flow due to the use of the ejection effect in the exhaust system of a diesel engine. The use of ejection in the exhaust system of the DM-21 diesel leads to improvement of cleaning cylinders up to 10 %, reduces the specific fuel consumption on average by 1 %.

  20. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Emergencies A-Z Share this! Home » Emergency 101 Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

  1. The Gas-Cooled Fast Reactor: Report on Safety System Design for Decay Heat Removal

    Energy Technology Data Exchange (ETDEWEB)

    K. D. Weaver; T. Marshall; T. Y. C. Wei; E. E. Feldman; M. J. Driscoll; H. Ludewig

    2003-09-01

    The gas-cooled fast reactor (GFR) was chosen as one of the Generation IV nuclear reactor systems to be developed based on its excellent potential for sustainability through reduction of the volume and radiotoxicity of both its own fuel and other spent nuclear fuel, and for extending/utilizing uranium resources orders of magnitude beyond what the current open fuel cycle can realize. In addition, energy conversion at high thermal efficiency is possible with the current designs being considered, thus increasing the economic benefit of the GFR. However, research and development challenges include the ability to use passive decay heat removal systems during accident conditions, survivability of fuels and in-core materials under extreme temperatures and radiation, and economical and efficient fuel cycle processes. This report addresses/discusses the decay heat removal options available to the GFR, and the current solutions. While it is possible to design a GFR with complete passive safety (i.e., reliance solely on conductive and radiative heat transfer for decay heat removal), it has been shown that the low power density results in unacceptable fuel cycle costs for the GFR. However, increasing power density results in higher decay heat rates, and the attendant temperature increase in the fuel and core. Use of active movers, or blowers/fans, is possible during accident conditions, which only requires 3% of nominal flow to remove the decay heat. Unfortunately, this requires reliance on active systems. In order to incorporate passive systems, innovative designs have been studied, and a mix of passive and active systems appears to meet the requirements for decay heat removal during accident conditions.

  2. A (S)TEM Gas Cell Holder with Localized Laser Heating for In Situ Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Mehraeen, Shareghe [Univ. of California, Davis, CA (United States). Dept. of Molecular and Cellular Biology; McKeown, Joseph T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Condensed Matter and Materials Division; Deshmukh, Pushkarraj V. [E.A. Fischione Instruments, Inc., Export, PA (United States); Evans, James E. [Univ. of California, Davis, CA (United States). Dept. of Molecular and Cellular Biology; Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Chemical and Materials Science Division; Abellan, Patricia [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Chemical and Materials Science Division; Xu, Pinghong [Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science; Reed, Bryan W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Condensed Matter and Materials Division; Taheri, Mitra L. [Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science & Engineering; Fischione, Paul E. [E.A. Fischione Instruments, Inc., Export, PA (United States); Browning, Nigel D. [Univ. of California, Davis, CA (United States). Dept. of Molecular and Cellular Biology; Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Chemical and Materials Science Division; Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science

    2013-03-04

    We report that the advent of aberration correction for transmission electron microscopy has transformed atomic resolution imaging into a nearly routine technique for structural analysis. Now an emerging frontier in electron microscopy is the development of in situ capabilities to observe reactions at atomic resolution in real time and within realistic environments. Here we present a new in situ gas cell holder that is designed for compatibility with a wide variety of sample type (i.e., dimpled 3-mm discs, standard mesh grids, various types of focused ion beam lamellae attached to half grids). Its capabilities include localized heating and precise control of the gas pressure and composition while simultaneously allowing atomic resolution imaging at ambient pressure. The results show that 0.25-nm lattice fringes are directly visible for nanoparticles imaged at ambient pressure with gas path lengths up to 20 μm. Additionally, we quantitatively demonstrate that while the attainable contrast and resolution decrease with increasing pressure and gas path length, resolutions better than 0.2 nm should be accessible at ambient pressure with gas path lengths less than the 15 μm utilized for these experiments.

  3. Flow and heat transfer in gas turbine disk cavities subject to nonuniform external pressure field

    Energy Technology Data Exchange (ETDEWEB)

    Roy, R.P.; Kim, Y.W.; Tong, T.W. [Arizona State Univ., Tempe, AZ (United States)

    1995-10-01

    Injestion of hot gas from the main-stream gas path into turbine disk cavities, particularly the first-stage disk cavity, has become a serious concern for the next-generation industrial gas turbines featuring high rotor inlet temperature. Fluid temperature in the cavities increases further due to windage generated by fluid drag at the rotating and stationary surfaces. The resulting problem of rotor disk heat-up is exacerbated by the high disk rim temperature due to adverse (relatively flat) temperature profile of the mainstream gas in the annular flow passage of the turbine. A designer is concerned about the level of stresses in the turbine rotor disk and its durability, both of which are affected significantly by the disk temperature distribution. This distribution also plays a major role in the radial position of the blade tip and thus, in establishing the clearance between the tip and the shroud. To counteract mainstream gas ingestion as well as to cool the rotor and the stator disks, it is necessary to inject cooling air (bled from the compressor discharge) into the wheel space. Since this bleeding of compressor air imposes a penalty on the engine cycle performance, the designers of disk cavity cooling and sealing systems need to accomplish these tasks with the minimum possible amount of bleed air without risking disk failure. This requires detailed knowledge of the flow characteristics and convective heat transfer in the cavity. The flow in the wheel space between the rotor and stator disks is quite complex. It is usually turbulent and contains recirculation regions. Instabilities such as vortices oscillating in space have been observed in the flow. It becomes necessary to obtain both a qualitative understanding of the general pattern of the fluid motion as well as a quantitative map of the velocity and pressure fields.

  4. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W.; Ren, W.

    1996-06-01

    The objective of the research is to provide databases and design criteria to assist in the selection of optimum alloys for construction of components needed to contain process streams in advanced heat recovery and hot-gas cleanup systems. Typical components include: steam line piping and superheater tubing for low emission boilers (600 to 700{degrees}C), heat exchanger tubing for advanced steam cycles and topping cycle systems (650 to 800{degrees}C), foil materials for recuperators, on advanced turbine systems (700 to 750{degrees}C), and tubesheets for barrier filters, liners for piping, cyclones, and blowback system tubing for hot-gas cleanup systems (850 to 1000{degrees}C). The materials being examined fall into several classes, depending on which of the advanced heat recovery concepts is of concern. These classes include martensitic steels for service to 650{degrees}C, lean stainless steels and modified 25Cr-30Ni steels for service to 700{degrees}C, modified 25Cr-20Ni steels for service to 900{degrees}C, and high Ni-Cr-Fe or Ni-Cr-Co-Fe alloys for service to 1000{degrees}C.

  5. High temperature corrosion of advanced ceramic materials for hot-gas filters and heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Kupp, E.R.; Trubelja, M.F.; Spear, K.E.; Tressler, R.E. [Pennsylvania State Univ., University Park, PA (United States)

    1995-08-01

    Experimental corrosion studies of hot gas filter materials and heat exchanger materials in oxidizing combustion environments have been initiated. Filter materials from 3M Co. and DuPont Lanxide Composites Inc. are being tested over a range of temperatures, times and gas flows. It has been demonstrated that morphological and phase changes due to corrosive effects occur after exposure of the 3M material to a combustion environment for as little as 25 hours at 800{degrees}C. The study of heat exchanger materials has focused on enhancing the corrosion resistance of DuPont Lanxide Dimox{trademark} composite tubes by adding chromium to its surfaces by (1) heat treatments in a Cr{sub 2}O{sub 3} powder bed, or (2) infiltrating surface porosity with molten chromium nitrate. Each process is followed by a surface homogenization at 1500{degrees}C. The powder bed method has been most successful, producing continuous Cr-rich layers with thicknesses ranging from 20 to 250 {mu}m. As-received and Cr-modified DuPont Lanxide Dimox{trademark} samples will be reacted with commonly encountered coal-ash slags to determine the Cr effects on corrosion resistance.

  6. New Approach to Microclimate Parameter Selection for the Production Area with Heat Supply Systems Based on Gas Infrared Radiators

    Directory of Open Access Journals (Sweden)

    Kurilenko N. I.

    2016-01-01

    Full Text Available There presented experimental research results for the heat transfer behavior in the areas with the radiant heating systems based on the gas infrared radiators. The model of heat-gravitational convection is formulated, that conforms to the transformation conditions of radiant energy coming from the radiators. A new approach to the parameter selection of the indoor climate with the radiant heating systems is developed based on the analysis and collation of experimental data for the temperature patterns and that of the heat flows of the object of research.

  7. Heat transfer to immersed horizontal tubes in gas fluidized bed dryers

    Energy Technology Data Exchange (ETDEWEB)

    Jonassen, Ola

    1999-07-01

    The main objective of this study was to construct heat pump fluidized bed dryers of the FHT type with improved dewatering capacity for a given size of the dryer. The use of heat exchangers immersed in the fluidized bed drying chambers is an important part of the FHT (Fluidized Bed High Temperature Heat Pump Dryer) concept. A pilot plant FHT dryer was built and successfully tested on fish meal raw material and seaweed. The plant included two fluidized bed drying chambers with immersed heat exchangers. The gain in water vapor of the drying air through the chambers was increased up to four times that of adiabatic drying. The energy saving concept was retained as a SMER ratio of 3.5 to 4.7 was measured in the same tests. Therefore optimization of the immersed heat exchangers was considered the most important single objective for this work. The optimization study of the heat exchangers was confined to the actual operating conditions for the dryers using: (1) Bubbling gas fluidized beds were used, (2) air as the only type of fluidizing gas,(3) beds at atmospheric pressure, (4) bed temperatures below 100 {sup o}C, (5) fluidized particles of Geldart classes B and D, (6) horizontal tube banks for the immersed heat exchanger and the influence of radiation heat transfer was ignored. The heat transfer study was confined to the fluidized bed side of the heat exchanger surface. It was concluded early in this work that the bubbles play a major role in generating the particle circulation inside the bed and hence also in heat transfer. Publications describing the most important bubble induced mechanisms contributing to high rates of heat transfer were found to be limited. Therefore the first part of this study was aimed at establishing a method for locating and measuring the size and rise velocity of bubbles inside the bed. The method established through this work using differential pressure measurements from two static pressure probes was used later in the study of heat transfer

  8. Heat transfer to immersed horizontal tubes in gas fluidized bed dryers

    Energy Technology Data Exchange (ETDEWEB)

    Jonassen, Ola

    1999-10-01

    The main objective of this study was to construct heat pump fluidized bed dryers of the FHT type with improved dewatering capacity for a given size of the dryer. The use of heat exchangers immersed in the fluidized bed drying chambers is an important part of the FHT (Fluidized Bed High Temperature Heat Pump Dryer) concept. A pilot plant FHT dryer was built and successfully tested on fish meal raw material and seaweed. The plant included two fluidized bed drying chambers with immersed heat exchangers. The gain in water vapor of the drying air through the chambers was increased up to four times that of adiabatic drying. The energy saving concept was retained as a SMER ratio of 3.5 to 4.7 was measured in the same tests. Therefore optimization of the immersed heat exchangers was considered the most important single objective for this work. The optimization study of the heat exchangers was confined to the actual operating conditions for the dryers using: (1) Bubbling gas fluidized beds were used, (2) air as the only type of fluidising gas, (3) beds at atmospheric pressure, (4) bed temperatures below 100 {sup o}C, (5) fluidized particles of Geldart classes B and D, (6) horizontal tube banks for the immersed heat exchanger, and the influence of radiation heat transfer was ignored. The heat transfer study was confined to the fluidized bed side of the heat exchanger surface. It was concluded early in this work that the bubbles play a major role in generating the particle circulation inside the bed and hence also in heat transfer. Publications describing the most important bubble induced mechanisms contributing to high rates of heat transfer were found to be limited. Therefore the first part of this study was aimed at establishing a method for locating and measuring the size and rise velocity of bubbles inside the bed. The method established through this work using differential pressure measurements from two static pressure probes was used later in the study of heat transfer

  9. Combined heat and power production based on gas turbine operation with biomass by gasification or powder firing; Kraftvaermeproduktion baserad paa gasturbindrift med biobraensle genom foergasning alternativt pulvereldning

    Energy Technology Data Exchange (ETDEWEB)

    Marbe, Aasa; Colmsjoe, Linda

    2006-12-15

    them create strategically plans. The results show that techniques based on gasification of biofuel are more expensive than the traditional biofuelled CHP-plant. The gasification technique will be a competitive option if the price of delivered electrical power increases, prices of green certificates increase or if the investment costs compared to the reference alternative is lowered. The global CO{sub 2} exhaust decreases significantly using gasification technique instead of the traditional technique. This is due to the higher amount electrical power produced. This technique requires high operation level and a huge heat demand because of the high investment costs and the limited part load performance. It has also been shown that it is not economically profitable to integrate a bio powder combustion gas turbine to the existing CHP-plant. The reason is the low contribution of generated electricity and the high investment costs. The both techniques require an additional development before it could be used commercially.

  10. Applicability of heat and gas trans-port models in biocover design based on a case study from Denmark

    DEFF Research Database (Denmark)

    Nielsen, A. A. F.; Binning, Philip John; Kjeldsen, Peter

    2015-01-01

    . Both models used the heat equation for heat transfer, and the numerical model used advection-diffusion model with dual Monod kinetics for gas transport. The results were validated with data from a Danish landfi The models correlated well with the observed data: the coefficient of determination (R2...

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

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud

    2009-01-01

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

  12. Enhancing the radiative heat dissipation from high-temperature SF6 gas plasma by using selective absorbers

    Science.gov (United States)

    Tsuda, Shinichiro; Horinouchi, Katsuhiko; Yugami, Hiroo

    2017-09-01

    Radiative cooling accomplished by tailoring the properties of spectral thermal emission is an interesting method for energy harvesting and high-efficiency passive cooling of terrestrial structures. This strategy, however, has not been extended to cool enclosed heat sources, common in engineering applications, and heat sources in high-temperature environments where radiative transfer plays a dominant role. Here we show a radiative cooling scheme for a high-temperature gaseous medium, using radiative heat extraction with selective absorbers matched to the gas-selective emission properties. We used SF6 gas plasma as a model, because this gas is used in gas circuit breakers, which require effective cooling of the hot insulating gas. Our theoretical analysis confirms that a copper photonic absorber, matched to the ultraviolet-to-near-infrared-selective emission properties of the gas, effectively extracts heat from the high-temperature gas plasma and lowers the radiative equilibrium gas temperature by up to 1270 K, exceeding both blackbody-like and metallic surfaces in practical operating conditions.

  13. Critical power concept adapted for the specific table tennis test: comparisons between exhaustion criteria, mathematical modeling, and correlation with gas exchange parameters.

    Science.gov (United States)

    Zagatto, A; Miranda, M F; Gobatto, C A

    2011-07-01

    The purposes of this study were to determine and to compare the critical power concept adapted for the specific table tennis test (critical frequency - C F ) estimated from 5 mathematical models and using 2 different exhaustion criteria (voluntary and technical exhaustions). Also, it was an aim to assess the relationship between C F estimated from mathematical models and respiratory compensation point (RCP), peak oxygen uptake ( V˙O (2PEAK)) and minimal intensity at which V˙O (2PEAK) ( F V˙O (2PEAK)) appears. 9 male table tennis players [18(1) years; 62.3(4.4) kg] performed the maximal incremental test and 3-4 exhaustive exercise bouts to estimate C F s (balls · min (-1)). The exhaustion time and C F obtained were independent of the exhaustion criteria. The C F from 3-parameter model [45.2(7.0)-voluntary, 43.2(5.6)-technical] was lower than C F estimated by linear 2-parameter models, frequency-time (-1) [53.5(3.6)-voluntary, 53.5(3.5)-technical] and total ball thrown-time [52.2(3.5)-voluntary, 52.2(3.5)-technical] but significantly correlated. C F values from 2 linear models were significantly correlated with RCP [47.4(3.4) balls · min (-1)], and C F values of the linear and nonlinear models were correlated with F V˙O (2PEAK) [56.7(3.4) balls · min (-1)]. However, there were no significant correlations between C F values and V˙O (2PEAK) [49.8(1.1)ml · kg (-1) · min (-1)]. The results were not modified by exhaustion criteria. The 2 linear and non-linear 2-parameter models can be used to estimate aerobic endurance in specific table tennis tests. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Analysis of Fluid Flow and Heat Transfer Model for the Pebble Bed High Temperature Gas Cooled Reactor

    OpenAIRE

    S. Yamoah; E.H.K. Akaho; Nana G.A. Ayensu; M. Asamoah

    2012-01-01

    The pebble bed type high temperature gas cooled nuclear reactor is a promising option for next generation reactor technology and has the potential to provide high efficiency and cost effective electricity generation. The reactor unit heat transfer poses a challenge due to the complexity associated with the thermalflow design. Therefore to reliably simulate the flow and heat transport of the pebble bed modular reactor necessitates a heat transfer model that deals with radiation as well as ther...

  15. Performance testing of cross flow heat exchanger operating in the atmosphere of flue gas particulate with vapor condensation

    Directory of Open Access Journals (Sweden)

    Nuntaphan, A.

    2006-05-01

    Full Text Available Performance testing of a cross flow heat exchanger operating under the atmosphere of flue gas particulate from combustion was carried out in this work. This heat exchanger exchanges heat between flue gas from the fuel oil combustion and cold water. The heat exchanger is composed of a spiral finned tube bank having 3 rows and 8 tubes per row with a staggered arrangement. The fin spacings considered are 2.85 and 6.10 mm. The theories of thermodynamics and heat transfer are used for analyzing the performance of this system.In this experiment, the flue gas temperature of 200ºC from combustion having 0.35 kg/s mass flow rate flows along outside surface of the heat exchanger and transfers heat to the 25ºC cooling water having 0.15 kg/s mass flow rate flowing in the tube side. Each experiment uses 750 hr for testing. During the testing, part of flue gas condenses on the heat transfer surface.From the experiment, it was found that the heat transfer rate of both heat exchangers tended to decrease with time while the airside pressure drop increased. These results come from the fouling on the heat transfer surface. Moreover, it is found that the heat exchanger having 2.85 mm fin spacing has an approximately 4 times higher fouling resistance than that of the 6.10 mm fin spacing.In this work a model for calculating the fouling resistance is also developed as a the function of time. The model is developed from that of Kern and Seaton and the mean deviation of the model is 0.789.

  16. SO2 gas adsorption by modified kaolin clays: influence of previous heating and time acid treatments.

    Science.gov (United States)

    Volzone, Cristina; Ortiga, Jose

    2011-10-01

    Modified kaolin clays were used as adsorbents for SO(2) gas adsorptions. The clays were heated up to 900 °C previous to acid treatments with 0.5 N sulfuric acid solutions at boiling temperature during different times up to 1440 min. Equilibrium adsorption at 25 °C and 0.1 MPa was carried out by using a volumetric apparatus. The samples were characterized by chemical analysis, X-ray diffraction and infrared analysis. The heating of the clays followed by acid treatment improved the adsorption capacity of the kaolin clays. The presence of amorphous silica and hydroxyl in the final products improved SO(2) adsorption capacity. Better properties for SO(2) adsorption were found in kaolin rich in not well ordered kaolinite clay mineral. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Computational prediction of heat transfer to gas turbine nozzle guide vanes with roughened surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Guo, S.M.; Jones, T.V. [Univ. of Oxford (United Kingdom). Dept. of Engineering Science; Lock, G.D. [Univ. of Bath (United Kingdom). Dept. of Mechanical Engineering; Dancer, S.N. [Rolls-Royce PLC, Derby (United Kingdom)

    1998-04-01

    The local Mach number and heat transfer coefficient over the aerofoil surfaces and endwalls of a transonic gas turbine nozzle guide vane have been calculated. the computations were performed by solving the time-averaged Navier-Stokes equations using a fully three-dimensional computational code (CFDS), which is well established at Rolls-Royce. A model to predict the effects of roughness has been incorporated into CFDS and heat transfer levels have been calculated for both hydraulically smooth and transitionally rough surfaces. The roughness influences the calculations in two ways; first the mixing length at a certain height above the surface is increased; second the wall function used to reconcile the wall condition with the first grid point above the wall is also altered. The first involves a relatively straightforward shift of the origin in the van Driest damping function description, the second requires an integration of the momentum equation across the wall layer. A similar treatment applies to the energy equation. The calculations are compared with experimental contours of heat transfer coefficient obtained using both thin-film gages and the transient liquid crystal technique. Measurements were performed using both hydraulically smooth and roughened surfaces, and at engine-representative Mach and Reynolds numbers. The heat transfer results are discussed and interpreted in terms of surface-shear flow visualization using oil and dye techniques.

  18. Boundary element method applied to a gas-fired pin-fin-enhanced heat pipe

    Energy Technology Data Exchange (ETDEWEB)

    Andraka, C.E.; Knorovsky, G.A.; Drewien, C.A.

    1998-02-01

    The thermal conduction of a portion of an enhanced surface heat exchanger for a gas fired heat pipe solar receiver was modeled using the boundary element and finite element methods (BEM and FEM) to determine the effect of weld fillet size on performance of a stud welded pin fin. A process that could be utilized by others for designing the surface mesh on an object of interest, performing a conversion from the mesh into the input format utilized by the BEM code, obtaining output on the surface of the object, and displaying visual results was developed. It was determined that the weld fillet on the pin fin significantly enhanced the heat performance, improving the operating margin of the heat exchanger. The performance of the BEM program on the pin fin was measured (as computational time) and used as a performance comparison with the FEM model. Given similar surface element densities, the BEM method took longer to get a solution than the FEM method. The FEM method creates a sparse matrix that scales in storage and computation as the number of nodes (N), whereas the BEM method scales as N{sup 2} in storage and N{sup 3} in computation.

  19. WATRE: a program for computing water and gas released from heated concrete

    Energy Technology Data Exchange (ETDEWEB)

    Claybrook, S.W.; Muhlestein, L.D.

    1985-01-01

    The WATRE computer program calculates the rate and quantity of water and carbon dioxide gas released from heated concrete. Recent development efforts have improved the numerical solution scheme, resulting in increased computational efficiency. The WATRE model is presented and the numerical procedure used to solve the governing equations is outlined. Validation of the WATRE model by comparison with extensive experimental data is emphasized. Results of a sensitivity study which investigated the effects that changes in input data have on WATRE calculations are also discussed.

  20. KEY DESIGN REQUIREMENTS FOR THE HIGH TEMPERATURE GAS-COOLED REACTOR NUCLEAR HEAT SUPPLY SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    L.E. Demick

    2010-09-01

    Key requirements that affect the design of the high temperature gas-cooled reactor nuclear heat supply system (HTGR-NHSS) as the NGNP Project progresses through the design, licensing, construction and testing of the first of a kind HTGR based plant are summarized. These requirements derive from pre-conceptual design development completed to-date by HTGR Suppliers, collaboration with potential end users of the HTGR technology to identify energy needs, evaluation of integration of the HTGR technology with industrial processes and recommendations of the NGNP Project Senior Advisory Group.

  1. An experimental and theoretical study of decentralized gas fired liquid heating

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, Rolf

    1996-12-01

    The effects on the energy situation in industry when gas fired liquid heaters replace steam have been determined by energy surveys performed in a brewery and a slaughterhouse, measurements of the performance and emissions from liquid heaters installed in these industries, and theoretical analyses of the potential energy. The theoretical study in the first part of the project provides information that allows assessment of the effects on the energy situation, of a part or complete conversion to decentralized heating, under the conditions prevailing in the industries concerned. The second part of the project focused on increasing the liquid heater efficiency and reducing emissions of carbon monoxide and hydrocarbons. Heat transfer and pressure drop for a corrugated tube was investigated experimentally. Empirical correlations for heat transfer and pressure drop for a corrugated tube were developed. These correlations were used in the design model that was developed within this project. The design model was validated against experimental data and data from an industrial application, where a section of the smooth heat exchanger tube was replaced with a corrugated tube. The results show that the design model predicts the outlet flue gas temperature and the heater efficiency quite accurately. The wall temperature at the first corrugation is also predicted with reasonable accuracy. These results make it possible to calculate the location where a corrugated tube can be inserted without causing subcooled boiling or severe fouling. It is shown that emissions of carbon monoxide and hydrocarbons can be held at low levels, even when conventional industrial burners are used. The use of nozzles that produce long soft flames increase the risk for large emissions of hydrocarbons and carbon monoxide. 125 refs, 89 figs, 16 tabs

  2. On mechanism of non-heating sterilization using the underwater shock wave loading and gas formation

    Directory of Open Access Journals (Sweden)

    Ayumi Takemoto

    2007-12-01

    Full Text Available In the field where the thermal sterilization can’t be applied, the establishment of the sterilization technology with non-heating is strongly requested. The sterilization by pressurizing is one of the sterilization technology. Especially, the underwater shock wave causes scarcely heat in pressurizing because the pressurizing time is extremely short. That is, it is thought that the underwater shock wave enables non-heating sterilization that originates only in pressure. Hence, in this research, the underwater shock wave loading caused by explosive was used for non-heating sterilization. Saccharomyces cerevisiae, one of the budding yeast was used for experiments. S. cerevisiae starts fermentation by feeding the glucose, and causes CO2 within its body. There is the great density difference between cells of S. cerevisiae and the gas, hence, the acoustic impedance is different on the underwater shock wave transmission. Therefore, a strong reflected wave is caused on the boundary of the cell and the gas, and a remarkable expansion is caused. Fermented S. cerevisiae are sterilized by this phenomenon, and showed high sterilization rates. The sterilization rate by the underwater shock wave was low for not giving the glucose, that is, S. cerevisiae that had not fermented. The sterilization rate that had been done on three conditions was as follows in the order of higher. 1 Fermenting S. cerevisiae, high pressure. 2 Fermenting S. cerevisiae, low pressure. 3 Non-fermenting S. cerevisiae, high pressure. The detonation fuse was used in this experiment. There was an interesting phenomenon, that is, the sterilization rate was high at the side of detonation beginning, and it was decreased toward the direction. It is thought that this is related to a constant angle of the shock wave caused from the detonation fuse. A corresponding result to the phenomenon was gotten by the numerical analysis between the progress of the detonation and the change of pressure.

  3. Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corporation, Columbus, Ohio

    Science.gov (United States)

    1980-01-01

    The solar energy system installed in the building has 2,978 sq ft of single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/hour water tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts from the site files, specification references, drawings, installation, operation and maintenance instructions are included.

  4. Flow distribution control characteristics in marine gas turbine waste-heat recovery system. Phase 2: Flow distribution control in waste-heat steam generators

    Science.gov (United States)

    Kuo, S. C.; Shu, H. T.

    1982-07-01

    The effect of flow distribution control on the design and performance of marine gas turbine waste heat steam generators was investigated. Major design requirements and critical problems associated with a waste heat steam generator were reviewed, and an existing two dimensional heat exchanger model based on the compact heat exchanger design criteria and the relaxation approach was modified and updated to estimate the waste heat steam generator performance at any inlet gas flow distribution. Performance estimates were made of the steam generator using uniform velocity distribution, and also actual flow distribution data available (at the diffuser inlet) with and without flow distribution controls, all at design and off design operating conditions of the gas turbine engine. Results indicate that the exit steam temperatures of the baseline waste heat steam generator with and without flow distribution controls would be 725 F and 450 F, respectively, for a constant design flow ratio of 7.9 lb/sec, and for a constant exit temperature of 700 F, the water flow rates would be 8.1 lb/sec and 6.6 lb/sec, respectively.

  5. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Science.gov (United States)

    2010-07-01

    ... cooling as required; or (ii) Using a short duct (up to 12 feet long) constructed of smooth wall pipe with a minimum of flexible sections maintained at a temperature above the dew point of the mixture, but... flexible connectors are allowed under this option; or (iv) By omitting the duct and performing the exhaust...

  6. Improved heat recovery and high-temperature clean-up for coal-gas fired combustion turbines

    Energy Technology Data Exchange (ETDEWEB)

    Barthelemy, N.M.; Lynn, S.

    1991-07-01

    This study investigates the performance of an Improved Heat Recovery Method (IHRM) applied to a coal-gas fired power-generating system using a high-temperature clean-up. This heat recovery process has been described by Higdon and Lynn (1990). The IHRM is an integrated heat-recovery network that significantly increases the thermal efficiency of a gas turbine in the generation of electric power. Its main feature is to recover both low- and high-temperature heat reclaimed from various gas streams by means of evaporating heated water into combustion air in an air saturation unit. This unit is a packed column where compressed air flows countercurrently to the heated water prior to being sent to the combustor, where it is mixed with coal-gas and burned. The high water content of the air stream thus obtained reduces the amount of excess air required to control the firing temperature of the combustor, which in turn lowers the total work of compression and results in a high thermal efficiency. Three designs of the IHRM were developed to accommodate three different gasifying process. The performances of those designs were evaluated and compared using computer simulations. The efficiencies obtained with the IHRM are substantially higher those yielded by other heat-recovery technologies using the same gasifying processes. The study also revealed that the IHRM compares advantageously to most advanced power-generation technologies currently available or tested commercially. 13 refs., 34 figs., 10 tabs.

  7. Simulation on Toxic Gases in Vehicle Exhaust Equipped with Modified Catalytic Converter : A Review

    Directory of Open Access Journals (Sweden)

    Leman A.M.

    2016-01-01

    Full Text Available Air pollution and global warming is a major issue nowadays. One of the main contributors to be the emission of harmful gases produced by vehicle exhausts lines. The harmful gases like NOx, CO, unburned HC and particulate matter increases the global warming, so catalytic converter plays a vital role in reducing harmful gases. Catalytic converters are used on most vehicles on the road today. This research deals with the gas emission flow in the catalytic converter involving the heat transfer, velocity flow, back pressure and others chemical reaction in the modified catalytic converter by using FeCrAl as a substrate that is treated using the ultrasonic bath and electroplating techniques. The objective of this study is to obtain a quantitative description of the gas emission in the catalytic converter system of automobile exhaust gas using ANSYS Software. The description of the gas emission in the catalytic converter system of automobile exhaust gas using ANSYS Software was simulated in this research in order to provide better efficiency and ease the reusability of the catalytic converter by comparing experimental data with software analysing data. The result will be expected to demonstrate a good approximation of gas emission in the modified catalytic converter simulation data compared to experimental data in order to verify the effectiveness of modified catalytic converter. Therefore studies on simulation of flow through the modified catalytic converter are very important to increase the accuracy of the obtained emission result.

  8. Current instabilities under HF electron gas heating in semiconductors with negative differential conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, Yu. G.; Logvinov, G. N. [Instituto Politecnico Nacional, Mexico, D.F. (Mexico); Laricheva, N. [Datmouth College, New Hampshire (United States); Mashkevich, O. L. [Kharkov University, Kharkov (Ukraine)

    2001-10-01

    A nonlinear temperature dependence of the kinetic coefficients of semiconductor plasma can result in the appearance of regions of negative differential conductivity (NDC) in both the high-frequency (HF) and static current-voltage characteristics (CVC). In the present paper the formation of the static NDC under simultaneous electron gas heating by HF and static electric field is studied. As is shown below, in this case the heating electromagnetic wave has a pronounced effect on the appearance of NDC caused by the overheating mechanisms and the type of the static CVC as a whole. [Spanish] Una dependencia no lineal de la temperatura de los coeficientes cineticos del plasma del semiconductor puede llevar a la aparicion de regiones con conductividad diferencial negativa (CDN) en las caracteristicas corriente voltaje (CCV) de alta frecuencia (AF) y estatica. En este articulo se estudia la formacion de la CDN estatica bajo la accion simultanea del calentamiento del gas de electrones por AF y el campo electrico estatico. Como se muestra mas adelante, en este caso la onda electromagnetica que calienta a los electrones ejerce un fuerte efecto en la aparicion de la CDN; que se obtiene por mecanismos de sobrecalentamiento, y en el tipo de CCV estatica.

  9. System efficiency for two-step metal oxide solar thermochemical hydrogen production – Part 2: Impact of gas heat recuperation and separation temperatures

    KAUST Repository

    Ehrhart, Brian D.

    2016-09-22

    The solar-to-hydrogen (STH) efficiency is calculated for various operating conditions for a two-step metal oxide solar thermochemical hydrogen production cycle using cerium(IV) oxide. An inert sweep gas was considered as the O2 removal method. Gas and solid heat recuperation effectiveness values were varied between 0 and 100% in order to determine the limits of the effect of these parameters. The temperature at which the inert gas is separated from oxygen for an open-loop and recycled system is varied. The hydrogen and water separation temperature was also varied and the effect on STH efficiency quantified. This study shows that gas heat recuperation is critical for high efficiency cycles, especially at conditions that require high steam and inert gas flowrates. A key area for future study is identified to be the development of ceramic heat exchangers for high temperature gas-gas heat exchange. Solid heat recuperation is more important at lower oxidation temperatures that favor temperature-swing redox processing, and the relative impact of this heat recuperation is muted if the heat can be used elsewhere in the system. A high separation temperature for the recycled inert gas has been shown to be beneficial, especially for cases of lower gas heat recuperation and increased inert gas flowrates. A higher water/hydrogen separation temperature is beneficial for most gas heat recuperation effectiveness values, though the overall impact on optimal system efficiency is relatively small for the values considered. © 2016 Hydrogen Energy Publications LLC.

  10. Relationship between vehicle emissions laws and incidence of suicide by motor vehicle exhaust gas in Australia, 2001-06: an ecological analysis.

    Directory of Open Access Journals (Sweden)

    David M Studdert

    2010-01-01

    Full Text Available BACKGROUND: Globally, suicide accounts for 5.2% of deaths among persons aged 15 to 44 years and its incidence is rising. In Australia, suicide rates peaked in 1997 and have been declining since. A substantial part of that decline stems from a plunge in suicides by one particular method: asphyxiation by motor vehicle exhaust gas (MVEG. Although MVEG remains the second most common method of suicide in Australia, its incidence decreased by nearly 70% in the decade to 2006. The extent to which this phenomenon has been driven by national laws in 1986 and 1999 that lowered permissible levels of carbon monoxide (CO emissions is unknown. The objective of this ecological study was to test the relationship by investigating whether areas of Australia with fewer noxious vehicles per capita experienced lower rates of MVEG suicide. METHODS AND FINDINGS: We merged data on MVEG suicides in Australia (2001-06 with data on the number and age of vehicles in the national fleet, as well as socio-demographic data from the national census. Poisson regression was used to analyse the relationship between the incidence of suicide within two levels of geographical area--postcodes and statistical subdivisions (SSDs--and the population density of pre-1986 and pre-1999 passenger vehicles in those areas. (There was a mean population of 8,302 persons per postcode in the study dataset and 87,413 persons per SSD. The annual incidence of MVEG suicides nationwide decreased by 57% (from 2.6 per 100,000 in 2001 to 1.1 in 2006 during the study period; the population density of pre-1986 and pre-1999 vehicles decreased by 55% (from 14.2 per 100 persons in 2001 to 6.4 in 2006 and 26% (from 44.5 per 100 persons in 2001 to 32.9 in 2006, respectively. Area-level regression analysis showed that the suicide rates were significantly and positively correlated with the presence of older vehicles. A percentage point decrease in the population density of pre-1986 vehicles was associated with a 6

  11. Features of the gas dynamics and local heat transfer in intake system of piston engine with supercharging

    Science.gov (United States)

    Plotnikov, L. V.

    2017-09-01

    Comparison of experimental research results of gas dynamics and instantaneous local heat transfer in the intake pipes for piston internal combustion engines (ICE) without and with supercharging are presented in the article. Studies were conducted on full-scale experimental setups in terms of gas dynamic nonstationarity, which is characteristic of piston engines. It has been established that the turbocharger installation in a gas-air system of piston internal combustion engine leads to significant differences in the patterns of change in gas-dynamic and heat transfer characteristics of flows. These data can be used in a modernization of piston engines due to installation of a turbocharger or in a development of gas-air systems for piston ICE with supercharging.

  12. Experimental validation of a dynamic waste heat recovery system model for control purposes

    NARCIS (Netherlands)

    Feru, E.; Kupper, F.; Rojer, C.; Seykens, X.L.J.; Scappin, F.; Willems, F.P.T.; Smits, J.; Jager, B. de; Steinbuch, M.

    2013-01-01

    This paper presents the identification and validation of a dynamic Waste Heat Recovery (WHR) system model. Driven by upcoming CO2 emission targets and increasing fuel costs, engine exhaust gas heat utilization has recently attracted much attention to improve fuel efficiency, especially for

  13. The Application of Discontinuous Galerkin Methods in Conjugate Heat Transfer Simulations of Gas Turbines

    Directory of Open Access Journals (Sweden)

    Zeng-Rong Hao

    2014-11-01

    Full Text Available The performance of modern heavy-duty gas turbines is greatly determined by the accurate numerical predictions of thermal loading on the hot-end components. The purpose of this paper is: (1 to present an approach applying a novel numerical technique—the discontinuous Galerkin (DG method—to conjugate heat transfer (CHT simulations, develop the engineering-oriented numerical platform, and validate the feasibility of the methodology and tool preliminarily; and (2 to utilize the constructed platform to investigate the aerothermodynamic features of a typical transonic turbine vane with convection cooling. Fluid dynamic and solid heat conductive equations are discretized into explicit DG formulations. A centroid-expanded Taylor basis is adopted for various types of elements. The Bassi-Rebay method is used in the computation of gradients. A coupled strategy based on a data exchange process via numerical flux on interface quadrature points is simply devised. Additionally, various turbulence Reynolds-Averaged-Navier-Stokes (RANS models and the local-variable-based transition model γ-Reθ are assimilated into the integral framework, combining sophisticated modelling with the innovative algorithm. Numerical tests exhibit good consistency between computational and analytical or experimental results, demonstrating that the presented approach and tool can handle well general CHT simulations. Application and analysis in the turbine vane, focusing on features around where there in cluster exist shock, separation and transition, illustrate the effects of Bradshaw’s shear stress limitation and separation-induced-transition modelling. The general overestimation of heat transfer intensity behind shock is conjectured to be associated with compressibility effects on transition modeling. This work presents an unconventional formulation in CHT problems and achieves its engineering applications in gas turbines.

  14. Preliminary study of the decay heat removal strategy for the gas demonstrator allegro

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Gusztáv, E-mail: gusztav.mayer@energia.mta.hu [Hungarian Academy of Sciences, Centre for Energy Research, P.O. Box 49, H-1525 Budapest (Hungary); Bentivoglio, Fabrice, E-mail: fabrice.bentivoglio@cea.fr [CEA/DEN/DM2S/STMF/LMES, F-38054, Grenoble (France)

    2015-05-15

    Highlights: • Improved decay heat removal strategy was adapted for the 75 MW ALLEGRO MOX core. • New nitrogen injection strategy was proposed for the DEC LOCA transients. • Preliminary CATHARE study shows that most of the investigated transients fulfill criteria. • Further improvements and optimizations are needed for nitrogen injection. - Abstract: The helium cooled Gas Fast Reactor (GFR) is one of the six reactor concepts selected in the frame of the Generation IV International Forum. Since no gas cooled fast reactor has ever been built, a medium power demonstrator reactor – named ALLEGRO – is necessary on the road towards the 2400 MWth GFR power reactor. The French Commissariat à l’Energie Atomique (CEA) completed a wide range of studies during the early stage of development of ALLEGRO, and later the ALLEGRO reactor concept was developed in several European Union projects in parallel with the GFR2400. The 75 MW thermal power ALLEGRO is currently developed in the frame of the European ALLIANCE project. As a result of the collaboration between CEA and the Hungarian Academy of Sciences Centre for Energy Research (MTA EK) new improvements were done in the safety approach of ALLEGRO. A complete Decay Heat Removal (DHR) strategy was devised, relying on the primary circuits as a first way to remove decay heat using pony-motors to drive the primary blowers, and on the secondary and tertiary circuits being able to work in forced or natural circulation. Three identical dedicated loops circulating in forced convection are used as a second way to remove decay heat, and these loops can circulate in natural convection for pressurized transients, providing a third way to remove decay heat in case of accidents when the primary circuit is still under pressure. The possibility to use nitrogen to enhance both forced and natural circulation is discussed. This DHR strategy is supported by a wide range of accident transient simulations performed using the CATHARE2 code

  15. Energy Management of a Hybrid-Power Gas Engine-Driven Heat Pump

    Directory of Open Access Journals (Sweden)

    Qingkun Meng

    2015-10-01

    Full Text Available The hybrid-power gas engine-driven heat pump (HPGHP combines hybrid power technology with a gas engine heat pump. The engine in the power system is capable of operating constantly with high thermal efficiency and low emissions during different operating modes. In this paper, the mathematical models of various components is established, including the engine thermal efficiency map and the motor efficiency map. The comprehensive charging/discharging efficiency model and energy management optimization strategy model which is proposed to maximize the efficiency of instantaneous HPGHP system are established. Then, different charging/discharging torque limits are obtained. Finally, a novel gas engine economical zone control strategy which combined with the SOC of battery in real time is put forward. The main operating parameters of HPGHP system under energy management are simulated by Matlab/Simulink and validated by experimental data, such as engine and motor operating torque, fuel consumption rate and comprehensive efficiency, etc. The results show that during 3600 s’ run-time, the SOC value of battery packs varies between 0.58 and 0.705, the fuel consumption rate reaches minimum values of approximately 291.3 g/(kW h when the compressor speed is nearly 1550 rpm in mode D, the engine thermal efficiency and comprehensive efficiency reach maximum values of approximately 0.2727 and 0.2648 when the compressor speed is 1575 rpm and 1475 rpm, respectively, in mode D. In general, the motor efficiency can be maintained above 0.85 in either mode.

  16. Theoretical and experimental insights into effects of wind on leaf heat and gas exchange

    Science.gov (United States)

    Schymanski, Stanislaus J.; Or, Dani

    2014-05-01

    Transpiration and heat exchange by plant leaves are coupled physiological processes of significant importance for surface-climate interactions and ecohydrology. The common practice of modelling transpiration as an isothermal process (assuming equal leaf and air temperatures) may introduce significant bias into estimates of transpiration rates and water use efficiency (WUE, the amount of carbon gained by photosynthesis per unit of water lost by transpiration). In contrast, explicit consideration of stomatal and leaf boundary layer resistances in series and the leaf energy balance in a physically-based model led to some surprising results, such as suppressed transpiration rates for increasing wind speed at constant stomatal conductance. The model predicts that for high wind velocities, the same leaf conductance (for water vapour and carbon dioxide) can be maintained with less evaporative losses. If this leaf-scale effect is consistent across most leaves, it may have profound implications for canopy-scale water use efficiency under globally decreasing wind speeds. This presentation reports the results of a systematic study of the effect of wind speed on leaf heat and gas exchange rates and introduces a novel experimental design to verify the modelling results using an insulated wind tunnel and artificial leaves with defined pore geometries, allowing to measure leaf-scale latent and sensible heat fluxes independently. First experimental results and new insights will be highlighted.

  17. Field synergy characteristics in condensation heat transfer with non-condensable gas over a horizontal tube

    Directory of Open Access Journals (Sweden)

    Junxia Zhang

    2017-05-01

    Full Text Available Field synergy characteristics in condensation heat transfer with non-condensable gas (NCG over a horizontal tube were numerically simulated. Consequently, synergy angles between velocity and pressure or temperature gradient fields, gas film layer thickness, and induced velocity and shear stress on gas–liquid interface were obtained. Results show that synergy angles between velocity and temperature gradient fields are within 73.2°–88.7° and ascend slightly with the increment in mainstream velocity and that the synergy is poor. However, the synergy angle between velocity and pressure gradient fields decreases intensively with the increase in mainstream velocity at θ ≤ 30°, thereby improving the pressure loss. As NCG mass fraction increases, the gas film layer thickness enlarges and the induced velocity and shear stress on gas–liquid interface decreases. The synergy angles between velocity and temperature gradient fields increase, and the synergy angles between velocity and pressure gradient fields change at θ = 70°, decrease at θ 70°. When the horizontal tube circumference angle increases, the synergy angles between velocity and temperature or pressure gradient fields decrease, the synergy between velocity and pressure fields enhances, and the synergy between velocity and temperature fields degrades.

  18. Slag and seed deposition on heat exchanger surfaces from gas-droplet mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Im, K. H.; Chung, P. M.; Carlson, L. W.

    1978-01-01

    Mechanisms of particulate deposition from turbulent streams to solid surfaces are first discussed. Two problems of current interest in MHD application are then analyzed. One is the collection of slag droplets on the interior wall of vertical tubes from the turbulent droplet-laden gas stream. Such processes take place during the cycle of the regenerative heat exchanger used to preheat combustion air. The other is the removal of sub-micron-size slag particles or collection of seed by a bank of staggered vertical tubes situated normal to the gas flow direction. Removal of both vapor and droplet phases of slag and seed is possible with such a system. While thermophoresis is found to be a strong function of the temperature difference between the gas stream and the film surface, it was found that lowering of the tube temperature may not greatly enhance the deposition rate because the lower temperature implies a thicker slag film, and the necessary temperature difference is not correspondingly increased.

  19. Self-consistent plasma chemistry model for surface microdischarge in humid air including effects of ohmic heating and gas flow

    Science.gov (United States)

    Yi, Changho; Yoon, Sung-Young; Eom, Sangheum; Park, Seungil; Kim, Seong Bong; Ryu, Seungmin; Yoo, Suk Jae

    2017-10-01

    A numerical model is presented for surface microdischarges (SMDs) in flowing humid air at atmospheric pressure, to investigate the effects of the direct ohmic heating of gases in the discharge layer, and the transports of heat and particles by gas flow. Using a simplified configuration of heat transfer and gas flow, the proposed model calculated not only the densities of neutral species but also the temperatures of gases as time dependent variables. The calculated dynamics for various reactive oxygen and nitrogen species showed reasonable agreement with the experimental results obtained by Fourier transformed infrared absorption spectroscopy, while the calculated dynamics without ohmic heating of gases in the discharge layer showed significant disagreement. These results imply that local ohmic heating of the thin discharge layer by the microdischarge itself considerably affected the rate constants of the temperature dependent chemical reactions. The dynamics of the neutral species were also affected by gas flow, both directly through particle transport, and indirectly through cooling. Accordingly, to properly simulate the dynamics of reactive neutral species in SMDs, plasma chemistry models should treat plasmas as sources of both particles and heat which can be deliberately transported by gas flow.

  20. Heat supply systems using natural gas in the residential sector: The case of the agglomeration of Seoul

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hi-Chun [Department of Economics, Inha University, Yonghyun-Dong, Incheon 402-751 (Korea, Republic of)], E-mail: hi-chun.park@inha.ac.kr; Kim, Hoseok [Korea Environment Institute, 613-2, Bulkwang-Dong, Seoul 122-040 (Korea, Republic of)

    2008-10-15

    Combined heat and power (CHP) and district heating (DH) promotion policies are based on the assumption of high energy efficiencies. In the last two decades, however, there has been a big increase in energy efficiencies of combined-cycle gas power plants (CCs) including CHPs and gas-condensing boilers. This study tries to verify the validity of the assumption of high energy efficiency of DH. The experience in the agglomeration of Seoul shows that DH in combination with large modern CHPs is not more energy efficient but substantially more expensive compared to individual gas heating by efficient condensing boilers in combination with CCs. We argue that the Korean government should review its CHP/DH support programs and abandon the so-called heat supply monopoly for DH operators in newly developed residential areas. Such a policy intervention only distorts the space heating market and wastes valuable financial resources. Furthermore, the public should be properly informed on energy efficiency as well as energy- and system-related costs of various heat supply systems. In the light of the present improvements in the performance of gas-condensing boilers and CCs, the validity of the assumption of high energy efficiency of CHP/DH in other countries has to be reviewed.

  1. Heat supply systems using natural gas in the residential sector. The case of the agglomeration of Seoul

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hi-Chun [Department of Economics, Inha University, Yonghyun-Dong, Incheon 402-751 (Korea); Kim, Hoseok [Korea Environment Institute, 613-2, Bulkwang-Dong, Seoul 122-040 (Korea)

    2008-10-15

    Combined heat and power (CHP) and district heating (DH) promotion policies are based on the assumption of high energy efficiencies. In the last two decades, however, there has been a big increase in energy efficiencies of combined-cycle gas power plants (CCs) including CHPs and gas-condensing boilers. This study tries to verify the validity of the assumption of high energy efficiency of DH. The experience in the agglomeration of Seoul shows that DH in combination with large modern CHPs is not more energy efficient but substantially more expensive compared to individual gas heating by efficient condensing boilers in combination with CCs. We argue that the Korean government should review its CHP/DH support programs and abandon the so-called heat supply monopoly for DH operators in newly developed residential areas. Such a policy intervention only distorts the space heating market and wastes valuable financial resources. Furthermore, the public should be properly informed on energy efficiency as well as energy- and system-related costs of various heat supply systems. In the light of the present improvements in the performance of gas-condensing boilers and CCs, the validity of the assumption of high energy efficiency of CHP/DH in other countries has to be reviewed. (author)

  2. Effects of fuel properties and oxidation catalyst on diesel exhaust emissions; Keiyu seijo oyobi sanka shokubai no diesel haishutsu gas eno eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Aihara, S.; Morihisa, H.; Tamanouchi, M.; Araki, H.; Yamada, S. [Petroleum Energy Center, Advanced Technology and Research Institute, Tokyo (Japan)

    1997-10-01

    Effects of fuel properties (T90 and Poly-Aromatic Hydrocarbons: PAH) and oxidation catalyst on diesel exhaust emissions were studied using three DI diesel engines and two diesel passenger cars. (IDI engine) PM emissions were found to increase as T90 and PAH increased and could be decreased considerably for each fuel if an oxidation catalyst was installed. 5 refs., 9 figs., 3 tabs.

  3. Effects of gasoline properties on exhaust emission and photochemical reactivity; Gasoline seijo ga haiki gas sosei, kokagaku hannosei ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, R.; Usui, K.; Moriya, A.; Sato, M.; Nomura, T.; Sue, H. [Petroleum Energy Center, Advanced Technology and Research Institute, Tokyo (Japan)

    1997-10-01

    In order to investigate the effects of fuel properties on emissions, four passenger cars were tested under Japanese 11 and 10-15 modes using two series gasoline fuels. The test results suggest that the distillation property (T90) affects A/F ratio which in turn influences exhaust emissions. The results of regression analysis show that both ozone forming potential and air toxics are highly corrected with the composition of aromatic hydrocarbons in gasoline. 3 refs., 10 figs., 6 tabs.

  4. Demonstration of an on-site PAFC cogeneration system with waste heat utilization by a new gas absorption chiller

    Energy Technology Data Exchange (ETDEWEB)

    Urata, Tatsuo [Tokyo Gas Company, LTD, Tokyo (Japan)

    1996-12-31

    Analysis and cost reduction of fuel cells is being promoted to achieve commercial on-site phosphoric acid fuel cells (on-site FC). However, for such cells to be effectively utilized, a cogeneration system designed to use the heat generated must be developed at low cost. Room heating and hot-water supply are the most simple and efficient uses of the waste heat of fuel cells. However, due to the short room-heating period of about 4 months in most areas in Japan, the sites having demand for waste heat of fuel cells throughout the year will be limited to hotels and hospitals Tokyo Gas has therefore been developing an on-site FC and the technology to utilize tile waste heat of fuel cells for room cooling by means of an absorption refrigerator. The paper describes the results of fuel cell cogeneration tests conducted on a double effect gas absorption chiller heater with auxiliary waste heat recovery (WGAR) that Tokyo Gas developed in its Energy Technology Research Laboratory.

  5. Effect of the rate of temperature increase on water quality during heating in electromagnetic- and gas-heated pans.

    Science.gov (United States)

    Hiratsuka, Hiroshi; Sasaki, Ken

    2004-04-01

    More rapid increases in the pH value and hardness during electromagnetic heating of a pan of water were observed than when the pan was heated by LNG or LPG. The water quality changed universally in several tap water samples across Japan. This quality change was closely correlated with the rate of temperature increase, irrespective of heating by electromagnetic induction, LNG or LPG.

  6. Biomass combustion gas turbine CHP

    Energy Technology Data Exchange (ETDEWEB)

    Pritchard, D.

    2002-07-01

    This report summarises the results of a project to develop a small scale biomass combustor generating system using a biomass combustor and a micro-gas turbine indirectly fired via a high temperature heat exchanger. Details are given of the specification of commercially available micro-turbines, the manufacture of a biomass converter, the development of a mathematical model to predict the compatibility of the combustor and the heat exchanger with various compressors and turbines, and the utilisation of waste heat for the turbine exhaust.

  7. Investigation of Continuous Gas Engine CHP Operation on Biomass Producer Gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Jensen, Torben Kvist

    2005-01-01

    heat from the exhaust gas is utilised for drying and pyrolysis of the biomass in the gasification system, and the engine directly controls the load of the gasifier. Two different control approaches have been applied and investigated: one where the flow rate of the producer gas is fixed and the engine......More than 2000 hours of gas engine operation with producer gas from biomass as fuel has been conducted on the gasification CHP demonstration and research plant, named “Viking” at the Technical University of Denmark. The gas engine is an integrated part of the entire gasification plant. The excess...

  8. High-efficiency gas heat pump air-conditioner equipped with absorption refrigerator

    Science.gov (United States)

    Kawakami, Ryuichiro; Imai, Kazuya; Nakajima, Hidekazu; Okamoto, Hiroaki; Hihara, Eiji

    To improve rated efficiency and partial load efficiency of gas engine heat pump (GHP), we are developing a new type air-cooled absorption refrigerator which is driven by the engine waste hot water. To shape the compact absorption refrigerator body that was able to be built into the space of a GHP outdoor-unit, an air-cooled sub-cooled adiabatic absorber and flowing liquid film plate type generator were newly developed. Maximum cooling capacity was increased about 20%, rated load COP was increased 40%, and partial load COP was increased 46% or less, as a result of the combination examination of a prototype 8.0kW absorption refrigerator and a 56kW GHP at a laboratory.

  9. Heat and metal transfer in gas metal arc welding using argon and helium

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, P.G.; Eagar, T.W.; Szekely, J. [Massachusetts Inst. of Technology, Cambridge, MA (United States). Dept. of Materials Science and Engineering

    1995-04-01

    This article describes a theoretical investigation on the arc parameters and metal transfer in gas metal arc welding (GMAW) of mild steel using argon and helium shielding gases. Major differences in the predicted arc parameters were determined to be due to large differences in thermophysical properties. Various findings from the study include that an arc cannot be struck in a pure helium atmosphere without the assistance of metal vapor, that a strong electromagnetic cathode force affects the fluid flow and heat transfer in the helium arc, providing a possible explanation for the experimentally observed globular transfer mode and that the tapering of t electrode in an argon arc is caused by electron condensation on the side of the electrode.

  10. Heat and metal transfer in gas metal arc welding using argon and helium

    Science.gov (United States)

    Jönsson, P. G.; Eagar, T. W.; Szekely, J.

    1995-04-01

    This article describes a theoretical investigation on the arc parameters and metal transfer in gas metal arc welding (GMAW) of mild steel using argon and helium shielding gases. Major differences in the predicted arc parameters were determined to be due to large differences in thermophysical properties. Various findings from the study include that an arc cannot be struck in a pure helium atmosphere without the assistance of metal vapor, that a strong electromagnetic cathode force affects the fluid flow and heat transfer in the helium arc, providing a possible explanation for the experimentally observed globular transfer mode and that the tapering of the electrode in an argon arc is caused by electron condensation on the side of the electrode.

  11. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W.; Ren, W. [Oak Ridge National Lab., TN (United States)

    1995-08-01

    Alloys for design and construction of structural components needed to contain process streams and provide internal structures in advanced heat recovery and hot gas cleanup systems were examined. Emphasis was placed on high-strength, corrosion-resistant alloys for service at temperatures above 1000 {degrees}F (540{degrees}C). Data were collected that related to fabrication, joining, corrosion protection, and failure criteria. Alloys systems include modified type 310 and 20Cr-25Ni-Nb steels and sulfidation-resistance alloys HR120 and HR160. Types of testing include creep, stress-rupture, creep crack growth, fatigue, and post-exposure short-time tensile. Because of the interest in relatively inexpensive alloys for high temperature service, a modified type 310 stainless steel was developed with a target strength of twice that for standard type 310 stainless steel.

  12. Investigation of austenitic alloys for advanced heat recovery and hot-gas cleanup systems

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, and modified alloy 800. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700 C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925 C with good weldability and ductility.

  13. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W.; Ren, W. [Oak Ridge National Lab., TN (United States)

    1996-08-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, modified alloy 800, and two sulfidation resistant alloys: HR160 and HR120. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700{degrees}C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925{degrees}C with good weldability and ductility.

  14. Gamma densitomeric measurements of gas concentrations at a heated tube bundle; Gammadensitometrische Gasgehaltsmessungen an einem beheizten Rohrbuendel

    Energy Technology Data Exchange (ETDEWEB)

    Franz, R.; Sprewitz, U.; Hampel, U.

    2012-07-01

    The contribution under consideration reports on a gamma denitometric measurement of gas concentrations in a vertical heated tube bundle which is flowed around by a fluid. Two measurement positions, two flow rates of the circulating fluid, two subcooling values and eleven heat fluxes were selected for the measurement. The authors of this contribution describe the test facility, measurement methodology, results and their interpretation. The measurement uncertainty is described in detail.

  15. Study of flue gas condensing for biofuel fired heat and power plants; Studie av roekgaskondensering foer biobraensleeldade kraftvaermeanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Axby, Fredrik; Gustafsson, J.O.; Nystroem, Johan; Johansson, Kent

    2000-11-01

    This report considers questions regarding flue gas condensing plants connected to bio-fuelled heat and power plants. The report consists of two parts, one where nine existing plants are described regarding technical issues and regarding the experience from the different plants. Part two is a theoretical study where heat balance calculations are made to show the technical and economical performance in different plant configurations and operating conditions. Initially the different parts in the flue gas condensing plant are described. Tube, plate and scrubber condensers are described briefly. The different types of humidifiers are also described, rotor, cross-stream plate heat exchanger and scrubber. Nine flue gas-condensing plants have been visited. The plants where chosen considering it should be bio-fuel fired plant primarily heat and power plants. Furthermore we tried to get a good dissemination considering plant configuration, supplier, geographical position, operating situation and plant size. The description of the different plants focuses on the flue gas condenser and the belonging components. The fuel, flue gas and condensate composition is described as well as which materials are used in the different parts of the plant. The experience from operating the plants and the reasons of why they decided to chose the actual condenser supplier are reported.

  16. Energetic evaluation of low potential biomass gasifier coupled with a burner of the produced gas for generation of heat; Avaliacao energetica de um gaseificador de biomassa de baixa potencia, associado a um combustor do gas produzido, para geracao de calor

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Samuel [Universidade de Brasilia (FAV/UNB), DF (Brazil). Fac. de Agronomia e Medicina Veterinaria], email: samuelmartin@unb.nr; Silva, Jadir Nogueira [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Engenharia Agricola; Machado, Cassio Silva; Zanatta, Fabio Luis; Galvarro, Svetlana F.S. [Universidade Federal de Vicosa (UFV), MG (Brazil)

    2011-07-01

    In the search of alternatives for sustainable socio-economic development, this study had the objective of evaluating the energetic performance of a concurrent flow biomass gasifier associated with a burner for the gas produced which was of low potential for air heating using a renewable energy source (substituting non-renewable). In this system 4 tests were performed using eucalyptus chips (tests 1 and 2) and logs (tests 3 and 4) as fuel, for the two fan motor frequencies of 60 and 50 hertz. Temperature in the combustion chamber was monitored, along with fuel consumption and other variables. In the tests, the average exhaust air temperature was maintained between 92.7 and 100.4 deg C, and the reduction in the motor frequency from 60 to 50 Hz caused an increase in the duration of the tests. The system presented the best energetic performance when utilizing a frequency of 60 Hz for both fuel types. However, the results of energy efficiency varied very little when comparing tests performed at the same fan frequency. Thus, the gasification process was little affected by variation in the physical characteristics of the tested fuels, and it was recommended that the equipment operate with a frequency of 60 Hz. (author)

  17. High temperature corrosion of advanced ceramic materials for hot gas filters and heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Crossland, C.E.; Shelleman, D.L.; Spear, K.E. [Pennsylvania State Univ., University Park, PA (United States)] [and others

    1996-08-01

    A vertical flow-through furnace has been built to study the effect of corrosion on the morphology and mechanical properties of ceramic hot gas filters. Sections of 3M Type 203 and DuPont Lanxide SiC-SiC filter tubes were sealed at one end and suspended in the furnace while being subjected to a simulated coal combustion environment at 870{degrees}C. X-ray diffraction and electron microscopy is used to identify phase and morphology changes due to corrosion while burst testing determines the loss of mechanical strength after exposure to the combustion gases. Additionally, a thermodynamic database of gaseous silicon compounds is currently being established so that calculations can be made to predict important products of the reaction of the environment with the ceramics. These thermodynamic calculations provide useful information concerning the regimes where the ceramic may be degraded by material vaporization. To verify the durability and predict lifetime performance of ceramic heat exchangers in coal combustion environments, long-term exposure testing of stressed (internally pressurized) tubes must be performed in actual coal combustion environments. The authors have designed a system that will internally pressurize 2 inch OD by 48 inch long ceramic heat exchanger tubes to a maximum pressure of 200 psi while exposing the outer surface of the tubes to coal combustion gas at the Combustion and Environmental Research Facility (CERF) at the Pittsburgh Energy and Technology Center. Water-cooled, internal o-ring pressure seals were designed to accommodate the existing 6 inch by 6 inch access panels of the CERF. Tubes will be exposed for up to a maximum of 500 hours at temperatures of 2500 and 2600{degrees}F with an internal pressure of 200 psi. If the tubes survive, their retained strength will be measured using the high temperature tube burst test facility at Penn State University. Fractographic analysis will be performed to identify the failure source(s) for the tubes.

  18. Gas Depletion in Local Group Dwarfs on ~250 kpc Scales: Ram Pressure Stripping Assisted by Internal Heating at Early Times

    Science.gov (United States)

    Nichols, Matthew; Bland-Hawthorn, Joss

    2011-05-01

    A recent survey of the Galaxy and M31 reveals that more than 90% of dwarf galaxies within 270 kpc of their host galaxy are deficient in H I gas. At such an extreme radius, the coronal halo gas is an order of magnitude too low to remove H I gas through ram pressure stripping for any reasonable orbit distribution. However, all dwarfs are known to have an ancient stellar population (gsim 10 Gyr) from early epochs of vigorous star formation which, through heating of H I, could allow the hot halo to remove this gas. Our model looks at the evolution of these dwarf galaxies analytically as the host-galaxy dark matter halo and coronal halo gas build up over cosmic time. The dwarf galaxies—treated as spherically symmetric, smooth distributions of dark matter and gas—experience early star formation, which sufficiently heats the gas, allowing it to be removed easily through tidal stripping by the host galaxy, or ram pressure stripping by a tenuous hot halo (n H = 3 × 10-4 cm-3 at 50 kpc). This model of evolution is able to explain the observed radial distribution of gas-deficient and gas-rich dwarfs around the Galaxy and M31 if the dwarfs fell in at high redshift (z ~ 3-10).

  19. Energy, exergy and environmental quality of hard coal and natural gas in whole life cycle concerning home heating

    Directory of Open Access Journals (Sweden)

    Pikon Krzysztof

    2016-01-01

    Full Text Available The use of coal is suspected to have high environmental impact. Natural gas is treated as more environmentally friendly with high methane content and lower emission factors. In order to calculate the environmental impact in the whole life cycle associated with combustion of coal and natural gas all stages from “cradle to grave” should be taken into account. In particular, the transportation stage, especially in the case of life cycle analysis of gas, seems to be crucial. The distance of transmission of gas from gas fields, for instance located in Siberia, could be mainly associated with high diffuse emission of methane. The comparison of environmental impact assessment of coal and natural gas utilization for heating purposes is presented in the paper. The additional factor taken into account is localisation of boilers. In the analysis the coal is sombusted in combined heat and power plants equipped with flue gas treatment units is that released emissions are relatively remote from an urban area. In contrast, the natural gas is burned in small domestic installations with no additional FGT systems. The results of the analysis are given in 6 major impact categories. Moreover, the results of the life cycle analysis were brought into comprehensive thermo-ecological cost index, which is a cumulated exergy consumption of non-renewable resources. The results presented in the paper refer to the contemporary problem of the choice of energy sources in the context of its overall environmental efficiency.

  20. Evaluation of radiation heat transfer in porous medial: Application for a pebble bed modular reactor cooled by CO2 gas

    Directory of Open Access Journals (Sweden)

    Sidi-Ali Kamel

    2013-01-01

    Full Text Available This work analyses the contribution of radiation heat transfer in the cooling of a pebble bed modular reactor. The mathematical model, developed for a porous medium, is based on a set of equations applied to an annular geometry. Previous major works dealing with the subject have considered the forced convection mode and often did not take into account the radiation heat transfer. In this work, only free convection and radiation heat transfer are considered. This can occur during the removal of residual heat after shutdown or during an emergency situation. In order to derive the governing equations of radiation heat transfer, a steady-state in an isotropic and emissive porous medium (CO2 is considered. The obtained system of equations is written in a dimensionless form and then solved. In order to evaluate the effect of radiation heat transfer on the total heat removed, an analytical method for solving the system of equations is used. The results allow quantifying both radiation and free convection heat transfer. For the studied situation, they show that, in a pebble bed modular reactor, more than 70% of heat is removed by radiation heat transfer when CO2 is used as the coolant gas.

  1. Stepping on the gas for district heating in Germany. Gas and steam turbines for cogeneration; Gas geben fuer Fernwaerme in Deutschland. Gas- und Dampfturbinen fuer die KWK

    Energy Technology Data Exchange (ETDEWEB)

    Bohtz, Christian [Alstom Power, Baden (Switzerland). Marketing and Product Management Gas Business

    2011-07-15

    Measured by its intensive efforts to lower CO{sub 2} emissions Germany is one of the leading countries in the EU. One contribution to this end is to be had from cogeneration. As a provider of cogeneration plants Alstom is working to improve the fuel efficiency as well as the overall efficiency and flexibility of its products. The author explains the technology of gas-fired cogeneration plants and gives three examples of their use.

  2. Evaluation of Gas, Oil and Wood Pellet Fueled Residential Heating System Emissions Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, R.

    2009-12-01

    This study has measured the emissions from a wide range of heating equipment burning different fuels including several liquid fuel options, utility supplied natural gas and wood pellet resources. The major effort was placed on generating a database for the mass emission rate of fine particulates (PM 2.5) for the various fuel types studied. The fine particulates or PM 2.5 (less than 2.5 microns in size) were measured using a dilution tunnel technique following the method described in US EPA CTM-039. The PM 2.5 emission results are expressed in several units for the benefit of scientists, engineers and administrators. The measurements of gaseous emissions of O{sub 2}, CO{sub 2}, CO, NO{sub x} and SO{sub 2} were made using a combustion analyzer based on electrochemical cells These measurements are presented for each of the residential heating systems tested. This analyzer also provides a steady state efficiency based on stack gas and temperature measurements and these values are included in the report. The gaseous results are within the ranges expected from prior emission studies with the enhancement of expanding these measurements to fuels not available to earlier researchers. Based on measured excess air levels and ultimate analysis of the fuel's chemical composition the gaseous emission results are as expected and fall within the range provided for emission factors contained in the US-EPA AP 42, Emission Factors Volume I, Fifth Edition. Since there were no unexpected findings in these gaseous measurements, the bulk of the report is centered on the emissions of fine particulates, or PM 2.5. The fine particulate (PM 2.5) results for the liquid fuel fired heating systems indicate a very strong linear relationship between the fine particulate emissions and the sulfur content of the liquid fuels being studied. This is illustrated by the plot contained in the first figure on the next page which clearly illustrates the linear relationship between the measured mass of

  3. Comparison of Two Potassium-Filled Gas-Controlled Heat Pipes

    Science.gov (United States)

    Bertiglia, F.; Iacomini, L.; Moro, F.; Merlone, A.

    2015-12-01

    Calibration by comparison of platinum resistance thermometers and thermocouples requires transfer media capable of providing very good short-term temperature uniformity and temperature stability over a wide temperature range. This paper describes and compares the performance of two potassium-filled gas-controlled heat pipes (GCHP) for operation over the range from 420° C to 900° C. One of the heat pipes has been in operation for more than 10 years having been operated at temperature for thousands of hours, while the other was commissioned in 2010 following recently developed improvements to both the design, assembly, and filling processes. It was found that the two devices, despite differences in age, structure, number of wells, and filling processes, realized the same temperatures within the measurement uncertainty. The results show that the potassium-filled GCHP provides a durable and high-quality transfer medium for performing thermometer calibrations with very low uncertainties, over the difficult high-temperature range from 420° C to 900° C.

  4. Investigations on burning efficiency and exhaust emission of in-line type emulsified fuel system

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Y.K. [National Chinyi University of Technology (Taiwan). Dept. of Mechanical Engineering; Cheng, H.C. [Point Environmental Protection Technology Company Limited (Taiwan)

    2011-07-28

    In this research, the burning efficiency as well as exhaust emission of a new water-in-oil emulsified fuel system was studied. This emulsified system contains two core processes, the first one is to mix 97% water with 3% emulsifier by volume, and get the milk-like emulsified liquid, while the second one is to compound the milk-like emulsified liquid with heavy oil then obtain the emulsified fuel. In order to overcome the used demulsification problem during in reserve or in transport, this system was designed as a made and use in-line type. From the results of a series of burning tests, the fuel saving can be 8--15%. Also, from the comparison of decline for the heat value and total energy output of emulsified fuel, one can find that the water as the dispersed phase in the combustion process will lead to a micro-explosion as well as the water gas effect, both can raise the combustion temperature and burning efficiency. By comparing the waste gas emission of different types of emulsified fuel, one can know that, the CO2 emission reduces approximately 14%, and NOx emission reduces above 46%, meaning the reduction of the exhaust gas is truly effective. From the exhaust temperature of tail pipe, the waste heat discharge also may reduce 27%, it is quite advantageous to the global warming as well as earth environmental protection.

  5. A MEMS-based Benzene Gas Sensor with a Self-heating WO3 Sensing Layer

    Directory of Open Access Journals (Sweden)

    Lung-Ming Fu

    2009-04-01

    Full Text Available In the study, a MEMS-based benzene gas sensor is presented, consisting of a quartz substrate, a thin-film WO3 sensing layer, an integrated Pt micro-heater, and Pt interdigitated electrodes (IDEs. When benzene is present in the atmosphere, oxidation occurs on the heated WO3 sensing layer. This causes a change in the electrical conductivity of the WO3 film, and hence changes the resistance between the IDEs. The benzene concentration is then computed from the change in the measured resistance. A specific orientation of the WO3 layer is obtained by optimizing the sputtering process parameters. It is found that the sensitivity of the gas sensor is optimized at a working temperature of 300 °C. At the optimal working temperature, the experimental results show that the sensor has a high degree of sensitivity (1.0 KΩ ppm-1, a low detection limit (0.2 ppm and a rapid response time (35 s.

  6. ESO 3060170: A massive fossil galaxy group with a heated gas core?

    DEFF Research Database (Denmark)

    Sun, M.; Forman, W.; Vikhlinin, A.

    2004-01-01

    We present a detailed study of the ESO 3060170 galaxy group, combining Chandra, XMM-Newton, and optical observations. The system is found to be a fossil galaxy group. The group X-ray emission is composed of a central, dense, cool core (10 kpc in radius) and an isothermal medium beyond the central...... 10 kpc. The region between 10 and 50 kpc (the cooling radius) has the same temperature as the gas from 50 to 400 kpc, although the gas cooling time between 10 and 50 kpc (2-6 Gyr) is shorter than the Hubble time. Thus, the ESO 3060170 group does not have a group-sized cooling core. We suggest......(vir) is not consistent with the predicted temperature profile in recent numerical simulations. We compare the entropy profile of the ESO 3060170 group with those of three other groups and find a flatter relation than that predicted by simulations involving only shock heating, S proportional to r(similar to0...

  7. Formation of secondary organic aerosols from gas-phase emissions of heated cooking oils

    Directory of Open Access Journals (Sweden)

    T. Liu

    2017-06-01

    Full Text Available Cooking emissions can potentially contribute to secondary organic aerosol (SOA but remain poorly understood. In this study, formation of SOA from gas-phase emissions of five heated vegetable oils (i.e., corn, canola, sunflower, peanut and olive oils was investigated in a potential aerosol mass (PAM chamber. Experiments were conducted at 19–20 °C and 65–70 % relative humidity (RH. The characterization instruments included a scanning mobility particle sizer (SMPS and a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS. The efficiency of SOA production, in ascending order, was peanut oil, olive oil, canola oil, corn oil and sunflower oil. The major SOA precursors from heated cooking oils were related to the content of monounsaturated fat and omega-6 fatty acids in cooking oils. The average production rate of SOA, after aging at an OH exposure of 1. 7 × 1011 molecules cm−3 s, was 1. 35 ± 0. 30 µg min−1, 3 orders of magnitude lower compared with emission rates of fine particulate matter (PM2. 5 from heated cooking oils in previous studies. The mass spectra of cooking SOA highly resemble field-derived COA (cooking-related organic aerosol in ambient air, with R2 ranging from 0.74 to 0.88. The average carbon oxidation state (OSc of SOA was −1.51 to −0.81, falling in the range between ambient hydrocarbon-like organic aerosol (HOA and semi-volatile oxygenated organic aerosol (SV-OOA, indicating that SOA in these experiments was lightly oxidized.

  8. Formation of secondary organic aerosols from gas-phase emissions of heated cooking oils

    Science.gov (United States)

    Liu, Tengyu; Li, Zijun; Chan, ManNin; Chan, Chak K.

    2017-06-01

    Cooking emissions can potentially contribute to secondary organic aerosol (SOA) but remain poorly understood. In this study, formation of SOA from gas-phase emissions of five heated vegetable oils (i.e., corn, canola, sunflower, peanut and olive oils) was investigated in a potential aerosol mass (PAM) chamber. Experiments were conducted at 19-20 °C and 65-70 % relative humidity (RH). The characterization instruments included a scanning mobility particle sizer (SMPS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). The efficiency of SOA production, in ascending order, was peanut oil, olive oil, canola oil, corn oil and sunflower oil. The major SOA precursors from heated cooking oils were related to the content of monounsaturated fat and omega-6 fatty acids in cooking oils. The average production rate of SOA, after aging at an OH exposure of 1. 7 × 1011 molecules cm-3 s, was 1. 35 ± 0. 30 µg min-1, 3 orders of magnitude lower compared with emission rates of fine particulate matter (PM2. 5) from heated cooking oils in previous studies. The mass spectra of cooking SOA highly resemble field-derived COA (cooking-related organic aerosol) in ambient air, with R2 ranging from 0.74 to 0.88. The average carbon oxidation state (OSc) of SOA was -1.51 to -0.81, falling in the range between ambient hydrocarbon-like organic aerosol (HOA) and semi-volatile oxygenated organic aerosol (SV-OOA), indicating that SOA in these experiments was lightly oxidized.

  9. Install Waste Heat Recovery Systems for Fuel-Fired Furnaces (English/Chinese) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2011-10-01

    Chinese translation of ITP fact sheet about installing Waste Heat Recovery Systems for Fuel-Fired Furnaces. For most fuel-fired heating equipment, a large amount of the heat supplied is wasted as exhaust or flue gases. In furnaces, air and fuel are mixed and burned to generate heat, some of which is transferred to the heating device and its load. When the heat transfer reaches its practical limit, the spent combustion gases are removed from the furnace via a flue or stack. At this point, these gases still hold considerable thermal energy. In many systems, this is the greatest single heat loss. The energy efficiency can often be increased by using waste heat gas recovery systems to capture and use some of the energy in the flue gas. For natural gas-based systems, the amount of heat contained in the flue gases as a percentage of the heat input in a heating system can be estimated by using Figure 1. Exhaust gas loss or waste heat depends on flue gas temperature and its mass flow, or in practical terms, excess air resulting from combustion air supply and air leakage into the furnace. The excess air can be estimated by measuring oxygen percentage in the flue gases.

  10. Effect of Heat Input on Mechanical and Metallurgical Properties of Gas Tungsten Arc Welded Lean Super Martensitic Stainless Steel

    OpenAIRE

    Muthusamy,Chellappan; Karuppiah, Lingadurai; Paulraj,Sathiya; Kandasami,Devakumaran; Kandhasamy,Raja

    2016-01-01

    Welding of 6mm thick AISI: 410S lean super martensitic stainless steel (LSMSS) under different heat input of 7.97, 8.75 and 10.9 kJ/cm was carried out by gas tungsten arc welding process. The influence of heat input on metallurgical and mechanical properties in weld and HAZ region was studied. The tensile tests were carried out at different temperatures, namely at room temperature, at 600ºC, 7000C and 8000C. It is observed that rise in the heat input and temperature decreased the tensile stre...

  11. Convective heat-transfer rate distributions over a 140 deg blunt cone at hypersonic speeds in different gas environments

    Science.gov (United States)

    Stewart, David A.; Chen, Y. K.

    1993-01-01

    Experiments were conducted in air, CO2, and CO2-argon gas mixtures to obtain heating distribution data over a 140 deg blunt cone with various corner radii. The effect of corner radius on the heating distribution over the forebody of the cone was included in the investigation. These experiments provide data for validation of two-dimensional axisymmetric and three-dimensional Navier-Stokes solutions. Heating distribution data and measured bow shock wave stand-off distances for 0 deg angle of attack were compared with predicted values using a two-dimensional axisymmetric Navier-Stokes code.

  12. Experimental validation of a new sorption refrigerator heated by natural gas; Validacao experimental de um refigerador de sorcao aquecido por gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Maria E. Vieira da; Medeiros, Marcelo R.Q. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Schwarzer, Klemens [Universidade de Ciencias Aplicadas de Aachen (Germany); Campos, Michel F. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This article presents the experimental results that validate the operation of a new refrigerator in sorption cycle that uses natural gas as its heat source. The project was financed by the RedeGasEnergia of the Petroleo Brasileiro Company - PETROBRAS and by Brazilian agency Agencia Brasileira Financiadora de Estudos e Projetos - FINEP. The refrigeration cycle has two phases: heating/desorption and cooling/adsorption. The materials used were the zeolite 13X and water. The system components, designed for this project, were: two adsorbers, two burners, one condenser and one evaporator. In the heating phase, the burners were turned on to heat up the adsorbers. The adsorbate was released in the vapor phase e flew to the condenser. After its condensation, the liquid moved by the action of gravity to the evaporator. When the burners were turned off, the adsorbers started to cool down due to natural convection and radiation to the ambient. With the decrease of temperature in the adsorbers, the adsorption process began and temperatures below 0 deg C (ice making) were measured in the evaporator. The equipment showed good thermal performance and temperatures near -4 deg C were measured in the evaporator. To produce 5 kg of ice, 0,123 kg of natural gas was used. (author)

  13. Monitoring gas and heat emissions at Norris Geyser Basin, Yellowstone National Park, USA based on a combined eddy covariance and Multi-GAS approach

    Science.gov (United States)

    Lewicki, Jennifer L.; Kelly, Peter; Bergfeld, Deborah; Vaughan, R. Greg; Lowenstern, Jacob B.

    2017-01-01

    We quantified gas and heat emissions in an acid-sulfate, vapor-dominated area (0.04-km2) of Norris Geyser Basin, located just north of the 0.63 Ma Yellowstone Caldera and near an area of anomalous uplift. From 14 May to 3 October 2016, an eddy covariance system measured half-hourly CO2, H2O and sensible (H) and latent (LE) heat fluxes and a Multi-GAS instrument measured (1 Hz frequency) atmospheric H2O, CO2 and H2S volumetric mixing ratios. We also measured soil CO2 fluxes using the accumulation chamber method and temperature profiles on a grid and collected fumarole gas samples for geochemical analysis. Eddy covariance CO2 fluxes ranged from − 56 to 885 g m− 2 d− 1. Using wavelet analysis, average daily eddy covariance CO2 fluxes were locally correlated with average daily environmental parameters on several-day to monthly time scales. Estimates of CO2emission rate from the study area ranged from 8.6 t d− 1 based on eddy covariance measurements to 9.8 t d− 1 based on accumulation chamber measurements. Eddy covariance water vapor fluxes ranged from 1178 to 24,600 g m− 2 d− 1. Nighttime H and LEwere considered representative of hydrothermal heat fluxes and ranged from 4 to 183 and 38 to 504 W m− 2, respectively. The total hydrothermal heat emission rate (H + LE + radiant) estimated for the study area was 11.6 MW and LE contributed 69% of the output. The mean ± standard deviation of H2O, CO2 and H2S mixing ratios measured by the Multi-GAS system were 9.3 ± 3.1 parts per thousand, 467 ± 61 ppmv, and 0.5 ± 0.6 ppmv, respectively, and variations in the gas compositions were strongly correlated with diurnal variations in environmental parameters (wind speed and direction, atmospheric temperature). After removing ambient H2O and CO2, the observed variations in the Multi-GAS data could be explained by the mixing of relatively H2O-CO2-H2S-rich fumarole gases with CO2-rich and H2O-H2S-poor soil gases. The

  14. Gas depletion in Local Group dwarfs on ~250 kpc scales: Ram pressure stripping assisted by internal heating at early times

    OpenAIRE

    Nichols, Matthew; Bland-Hawthorn, Joss

    2011-01-01

    A recent survey of the Galaxy and M31 reveals that more than 90% of dwarf galaxies within 270 kpc of their host galaxy are deficient in HI gas. At such an extreme radius, the coronal halo gas is an order of magnitude too low to remove HI gas through ram-pressure stripping for any reasonable orbit distribution. However, all dwarfs are known to have an ancient stellar population (\\geq 10 Gyr) from early epochs of vigorous star formation which, through heating of HI, could allow the hot halo to ...

  15. Exhaust Recirculation Control for Reduction of NOx from Large Two-Stroke Diesel Engines

    DEFF Research Database (Denmark)

    Nielsen, Kræn Vodder

    restriction on NOx emissions from large two-stroke diesel engines on vessels operating in certain NOx Emission Control Areas. Exhaust Gas Recirculation (EGR) is one of the three technologies on the market that are able to reduce the NOx emission adequately for Tier III operation. EGR is well known from...... the automotive industry, but have only recently been introduced commercially to large two-stroke diesel engines. Recirculation of exhaust gas to the cylinders lowers the oxygen availability and increases the heat capacity during combustion, which in turn leads to less formation of NOx. Experience shows......, that while large two-stroke engines with EGR perform well in steady state, fast engine load transients cause smoke formation due to the decreased oxygen availability. The aim of this thesis is to design a control system that enables the large two-stroke engines with EGR to meet the emission limits...

  16. Performance of hybrid quad generation system consisting of solid oxide fuel cell system and absorption heat pump

    DEFF Research Database (Denmark)

    Cachorro, Irene Albacete; Daraban, Iulia Maria; Lainé, Guillaume

    2013-01-01

    In this paper a system consisting of an SOFC system for cogeneration of heat and power and vapour absorption heat pump for cooling and freezing is assessed and performance is evaluated. Food industry where demand includes four forms of energy simultaneously is a relevant application such a system...... with natural gas. The natural gas is first converted to a mixture of H2 and CO which feed the anode after a preheating step. The cathode is supplied with preheated air and gives, as output, electrical energy. The anode output is the exhaust gas which represents the thermal energy reservoir for heating...... in order to meet the bought cooling and freezing demands. This is an innovative configuration for absorption heat pumps because the cascade is implemented only in vapour compression heat pumps. A smaller ratio of the exhausted gases supplies the energy demand for space heating. The SOFC is fuelled...

  17. Recovery of flue gas energy in heat-integrated gasification combined cycle (IGCC) power plants using the contact economizer system

    CSIR Research Space (South Africa)

    Madzivhandila, VA

    2011-03-01

    Full Text Available (flue gas) stream of a heat-integrated gasification combined cycle (IGCC) design of the Elcogas plant adopted from previous studies. The underlying support for this idea was the direct relationship between efficiency of the IGCC and the boiler feedwater...

  18. Neural network analysis on the effect of heat fluxes on greenhouse gas emissions from anaerobic swine waste treatment lagoon

    Science.gov (United States)

    In this study, we examined the various meteorological factors (i.e., air temperatures, solar radiation, and heat fluxes) that potentially affect greenhouse gas (GHG) emissions from swine waste lagoon. GHG concentrations (methane, carbon dioxide, and nitrous oxide) were monitored using a photoacous...

  19. Technical and Economical Analysis of Regulation Methods for Intermediate Steam Over-Heating in Gas and Fuel Oil Boilers

    Directory of Open Access Journals (Sweden)

    V. I. Nazarov

    2006-01-01

    Full Text Available Various methods for temperature regulation of intermediate steam over-heating have been investigated. The most economical method, namely, smoke gas recirculation with regular water sprinkling from ПВД-8 drain has been selected in the paper.

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

    Directory of Open Access Journals (Sweden)

    S. A. Kachan

    2010-01-01

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