WorldWideScience

Sample records for exhaust gas temperature

  1. Effect of EGR on the exhaust gas temperature and exhaust opacity in compression ignition engines

    Indian Academy of Sciences (India)

    Avinash Kumar Agrawal; Shrawan Kumar Singh; Shailendra Sinha; Mritunjay Kumar Shukla

    2004-06-01

    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 reducing the NOx emission of a diesel engine is by late injection of fuel into the combustion chamber. This technique is effective but increases fuel consumption by 10–15%, which necessitates the use of more effective NOx reduction techniques like exhaust gas recirculation (EGR). Re-circulating part of the exhaust gas helps in reducing NOx, but appreciable particulate emissions are observed at high loads, hence there is a trade-off between NOx and smoke emission. To get maximum benefit from this trade-off, a particulate trap may be used to reduce the amount of unburnt particulates in EGR, which in turn reduce the particulate emission also. An experimental investigation was conducted to observe the effect of exhaust gas re-circulation on the exhaust gas temperatures and exhaust opacity. The experimental setup for the proposed experiments was developed on a two-cylinder, direct injection, air-cooled, compression ignition engine. A matrix of experiments was conducted for observing the effect of different quantities of EGR on exhaust gas temperatures and opacity.

  2. 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.

  3. Exhaust Gas Temperature Measurements in Diagnostics of Turbocharged Marine Internal Combustion Engines Part I Standard Measurements

    Directory of Open Access Journals (Sweden)

    Korczewski Zbigniew

    2015-01-01

    Full Text Available The article discusses the problem of diagnostic informativeness of exhaust gas temperature measurements in turbocharged marine internal combustion engines. Theoretical principles of the process of exhaust gas flow in turbocharger inlet channels are analysed in its dynamic and energetic aspects. Diagnostic parameters are defined which enable to formulate general evaluation of technical condition of the engine based on standard online measurements of the exhaust gas temperature. A proposal is made to extend the parametric methods of diagnosing workspaces in turbocharged marine engines by analysing time-histories of enthalpy changes of the exhaust gas flowing to the turbocompressor turbine. Such a time-history can be worked out based on dynamic measurements of the exhaust gas temperature, performed using a specially designed sheathed thermocouple.

  4. Thermodynamic control-oriented modeling of cycle-to-cycle exhaust gas temperature in an HCCI engine

    International Nuclear Information System (INIS)

    Highlights: • First thermodynamic model in the literature to predict exhaust temperature in HCCI engines. • The model can be used for integrated control of HCCI combustion and exhaust temperature. • The model is experimentally validated at over 300 steady state and transient conditions. • Results show a good agreement between predicted and measured exhaust temperatures. • Sensitivity of exhaust gas temperature to variation of engine variables is shown. - Abstract: Model-based control of Homogenous Charge Compression Ignition (HCCI) engine exhaust temperature is a viable solution to optimize efficiency of both engine and the exhaust aftertreatment system. Low exhaust temperature in HCCI engines can limit the abatement of hydrocarbon (HC) and carbon monoxide (CO) emissions in an exhaust aftertreatment system. A physical–empirical model is described for control of exhaust temperature in HCCI engines. This model captures cycle-to-cycle dynamics affecting exhaust temperature and is based on thermodynamic relations and semi-empirical correlations. It incorporates intake and exhaust gas flow dynamics, residual gas mixing, and fuel burn rate and is validated with experimental data from a single cylinder engine at over 300 steady state and transient conditions. The validation results indicate a good agreement between predicted and measured exhaust gas temperature

  5. Optimization of Low-Temperature Exhaust Gas Waste Heat Fueled Organic Rankine Cycle

    Institute of Scientific and Technical Information of China (English)

    WANGHui—tao; WANGHua; ZHANGZhu—ming

    2012-01-01

    Low temperature exhaust gases carrying large amount of waste heat are released by steel-making process and many other industries, Organic Rankine Cycles (ORCs) are proven to be the most promising technology to re- cover the low-temperature waste heat, thereby to get more financial benefits for these industries. The exergy analysis of ORC units driven by low-temperature exhaust gas waste heat and charged with dry and isentropic fluid was per- formed, and an intuitive approach with simple impressions was developed to calculate the performances of the ORC unit. Parameter optimization was conducted with turbine inlet temperature simplified as the variable and exergy effi- ciency or power output as the objective function by means of Penalty Function and Golden Section Searching algo- rithm based on the formulation of the optimization problem. The power generated by the optimized ORC unit can be nearly as twice as that generated by a non-optimized ORC unit. In addition, cycle parametric analysis was performed to examine the effects of thermodynamic parameters on the cycle performances such as thermal efficiency and exergy efficiency. It is proven that performance of ORC unit is mainly affected by the thermodynamic property of working fluid, the waste heat temperature, the pinch point temperature of the evaporator, the specific heat capacity of the heat carrier and the turbine inlet temperature under a given environment temperature.

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

    Directory of Open Access Journals (Sweden)

    Ning-bo Zhao

    2014-01-01

    Full Text Available 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 approach, firstly, the GM (1, 1 model is used to forecast the trend by using limited data samples. Then, Markov chain model is integrated into GM (1, 1 model in order to enhance the forecast performance, which can solve the influence of random fluctuation data on forecasting accuracy and achieving an accurate estimate of the nonlinear forecast. As an example, the historical monitoring data of exhaust gas temperature from CFM56 aeroengine of China Southern is used to verify the forecast performance of the GM (1, 1 Markov chain model. The results show that the GM (1, 1 Markov chain model is able to forecast exhaust gas temperature accurately, which can effectively reflect the random fluctuation characteristics of exhaust gas temperature changes over time.

  7. Effect of Ambient Temperature on Total Organic Gas Speciation Profiles from Light-Duty Gasoline Vehicle Exhaust.

    Science.gov (United States)

    Roy, Anirban; Sonntag, Darrell; Cook, Richard; Yanca, Catherine; Schenk, Charles; Choi, Yunsoo

    2016-06-21

    Total organic gases (TOG) emissions from motor vehicles include air toxic compounds and contribute to formation of ground-level ozone and secondary organic aerosol (SOA). These emissions are known to be affected by temperature; however previous studies have typically focused only on the temperature dependence of total emission factors and select toxic compounds. This study builds on the previous research by performing an evaluation of a comprehensive set of gas-phase organic compounds present in gasoline motor vehicle exhaust. A fleet of five vehicles using port fuel injection engine technology and running on E10 fuel was tested. Overall, three temperatures (0, 20, and 75 °F; or -18, -7, and 24 °C), two driving conditions (urban-FTP75 and aggressive driving-US06) and 161 compounds were evaluated; the emissions distributions were used to construct speciation profiles for each driving cycle and temperature. Overall, the speciation results indicated a significant increase in alkane and methane content, and decrease in alcohol, aldehyde and ketone content with decreasing temperature. These were verified using a statistical significance test. The fraction and composition of Mobile Source Air Toxics (MSATs) were significantly affected by temperature for both driving cycles. The ozone forming potentials of these profiles were evaluated using the maximum incremental reactivity (MIR) scale. Aromatic content was predicted to be a major driver behind the ozone forming potentials. Additionally, the decreasing ozone potential could be attributed to increased methane fractions with increasing temperature. PMID:27203618

  8. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  9. Thermodynamic optimization of several (heat recovery steam generator) HRSG configurations for a range of exhaust gas temperatures

    International Nuclear Information System (INIS)

    Design optimization of a (heat recovery steam generator) HRSG is essential due to its direct impact on large power generation combined cycles. This study is aimed at giving a thermodynamic comparison between the optimums of three configurations of HRSG operating at exhaust gas temperature (TOT) from 350 °C to 650 °C. The optimization results, using PSO (Particle Swarm Optimization) method, show that adding another pressure level allows achieving a higher pressure at the inlet of high pressure turbine, producing more steam quantities, destroying less exergy and finally producing more specific work independently of TOT. For a given value of 600 °C representative of TOT of recent gas turbines, an addition of a pressure level is shown to increase the specific work of about 17 kJ/kg, representing a benefit of about 10% for the steam cycle, whereas a third pressure level results in 8 kJ/kg increase in the specific work, corresponding to 4% in the steam cycle. - Highlights: • Three types of HRSG are optimized and compared between them for several TOT values. • Adding a pressure level leads to thermodynamic performance enhancement whatever TOT. • Adding a pressure level permits reaching higher optimal pressures whatever TOT value. • Adding a pressure level permits producing more steam quantities. • Superheater effectiveness tends to its highest possible value except for high TOTs

  10. High temperature sensors for exhaust diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Svenningstorp, Henrik

    2000-07-01

    One of the largest problems that we will have to deal with on this planet this millennium is to stop the pollution of our environment. In many of the ongoing works to reduce toxic emissions, gas sensors capable of enduring rough environments and high temperatures, would be a great tool. The different applications where sensors like this would be useful vary between everything from online measurement in the paper industry and food industry to measurement in the exhaust pipe of a car. In my project we have tested Schottky diodes and MlSiCFET sensor as gas sensors operating at high temperatures. The measurement condition in the exhaust pipe of a car is extremely tough, not only is the temperature high and the different gases quite harmful, there are also a lot of particles that can affect the sensors in an undesirable way. In my project we have been testing Schottky diodes and MlSiCFET sensors based on SiC as high temperature sensors, both in the laboratory with simulated exhaust and after a real engine. In this thesis we conclude that these sensors can work in the hostile environment of an engines exhaust. It is shown that when measuring in a gas mixture with a fixed I below one, where the I-value is controlled by the O{sub 2} concentration, a sensor with a catalytic gate metal as sensitive material respond more to the increased O{sub 2} concentration than the increased HC concentration when varying the two correspondingly. A number of different sensors have been tested in simulated exhaust towards NO{sub x}. It was shown that resistivity changes in the thin gate metal influenced the gas response. Tests have been performed where sensors were a part of a SCR system with promising results concerning NH{sub 3} sensitivity. With a working temperature of 300 deg C there is no contamination of the metal surface.

  11. 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.

  12. Short review on heat recovery from exhaust gas

    Science.gov (United States)

    Jaber, Hassan; Khaled, Mahmoud; Lemenand, Thierry; Ramadan, Mohamad

    2016-07-01

    The increasing growth of energy demand leads to issues associated with energy demand reduction and propose new energy efficient solutions. Heat recovery consists the most promising solution especially in regions where renewable energy resources are not available. That is why the domain of heat recovery has shown a tremendous improvement during the recent years. On the other hand, few works have been dedicated to heat recovery from exhaust gas. This paper presents a review on heat recovery from exhaust gas. The authors propose to classify exhaust gas heat recovery systems within three different classifications that are exhaust gas temperature, utilized equipment and recovery purposes.

  13. 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...... of the current valve seat alloy, Alloy 718 (Ni-based, 19 wt% Cr, 18 wt% Fe, 5.1 wt% Nb, 3 wt% Mo, 1 wt% Ti and 0.6 wt% Al), and thereby to obtain a more hot corrosion resistant alloy. To validate these calculations, 16 Ni-based alloys, containing 40 wt% Cr and Nb, Ta and Ti in varying levels, were produced...

  14. Development of high temperature SiC based field effect sensors for internal combustion engine exhaust gas monitoring

    OpenAIRE

    Wingbrant, Helena

    2003-01-01

    While the car fleet becomes increasingly larger it is important to lower the amounts of pollutants from each individual diesel or gasoline engine to almost zero levels. The pollutants from these engines predominantly originate from high NOx emissions and particulates, in the case when diesel is utilized, and emissions at cold start from gasoline engines. One way of treating the high NOx levels is to introduce ammonia in the diesel exhausts and let it react with the NOx to form nitrogen gas an...

  15. Effects of exhaust temperature on helicopter infrared signature

    International Nuclear Information System (INIS)

    The effects of exhaust temperature on infrared signature (in 3–5 μm band) for a helicopter equipped with integrative infrared suppressor were numerically investigated. The internal flow of exhaust gas and the external downwash flow, as well as the mixing between exhaust gas and downwash were simulated by CFD software to determine the temperature distributions on the helicopter skin and in the exhaust plume. Based on the skin and plume temperature distributions, a forward–backward ray-tracing method was used to calculate the infrared radiation intensity from the helicopter with a narrow-band model. The results show that for a helicopter with its integrative infrared suppressor embedded inside its rear airframe, the exhaust temperature has significant influence on the plume radiation characteristics, while the helicopter skin radiation intensity has little impact. When the exhaust temperature is raised from 900 K to 1200 K, the plume radiation intensity in 3–5 μm band is increased by about 100%, while the skin radiation intensity is increased by only about 5%. In general, the effects of exhaust temperature on helicopter infrared radiation intensity are mainly concentrated on plume, especially obvious for a lower skin emissivity case. -- Highlights: ► The effect of exhaust temperature on infrared signature for a helicopter is numerically investigated. ► The impact of exhaust temperature on helicopter skin temperature is revealed. ► The impact of exhaust temperature on plume radiation characteristics is revealed. ► The impact of exhaust temperature on helicopter skin radiation is revealed. ► The impact of exhaust temperature on helicopter's total infrared radiation intensity is revealed

  16. 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.

  17. Exhaust gas assisted reforming of rapeseed methyl ester for reduced exhaust emissions of CI engines

    International Nuclear Information System (INIS)

    The nitrogen oxides (NOx) emissions of compression ignition (CI) engines fueled with biodiesel are generally higher compared to conventional diesel fuelling. Previous research work in CI engines has shown that the partial replacement of hydrocarbon fuels by hydrogen combined with exhaust gas recirculation (EGR) can reduce NOx and smoke emissions without significant changes to the engine efficiency. In the present study, the production of hydrogen-rich gas by catalytic exhaust gas assisted fuel reforming of rapeseed methyl ester (RME) has been investigated experimentally as a way to provide the required hydrogen for the reduction of biodiesel emissions. For comparison, tests with ultra low sulphur diesel (ULSD) were also performed. The reforming experiments were carried out in a mini reactor supplied with exhaust gas from a single cylinder CI engine. In all cases, the reactor inlet temperature was kept at 290-bar C which was chosen as a typical low exhaust gas temperature of diesel engines operating at part load. The engine operating condition (speed, load) was the same in all the tests and the reactor product gas was examined as a function of the reactor fuel flow rate and the composition of fuel and engine exhaust gas. Up to 17% hydrogen content of the reformer product was achieved and the results indicated that the main reactions in the reformer were the exothermic complete oxidation of part of the fuel and the endothermic steam reforming reaction. Reforming of RME produced more hydrogen with higher fuel conversion efficiency compared to ULSD reforming

  18. Method of controlling temperature of a thermoelectric generator in an exhaust system

    Science.gov (United States)

    Prior, Gregory P; Reynolds, Michael G; Cowgill, Joshua D

    2013-05-21

    A method of controlling the temperature of a thermoelectric generator (TEG) in an exhaust system of an engine is provided. The method includes determining the temperature of the heated side of the TEG, determining exhaust gas flow rate through the TEG, and determining the exhaust gas temperature through the TEG. A rate of change in temperature of the heated side of the TEG is predicted based on the determined temperature, the determined exhaust gas flow rate, and the determined exhaust gas temperature through the TEG. Using the predicted rate of change of temperature of the heated side, exhaust gas flow rate through the TEG is calculated that will result in a maximum temperature of the heated side of the TEG less than a predetermined critical temperature given the predicted rate of change in temperature of the heated side of the TEG. A corresponding apparatus is provided.

  19. Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi, E-mail: ysekine@waseda.jp [Department of Applied Chemistry, Waseda University, 65-301, Okubo, Shinjuku, Tokyo 169-8555 (Japan)

    2011-07-13

    Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C{sub 2} hydrocarbon without coke formation at a ratio of CO{sub 2}/C{sub fuel} = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

  20. Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system

    Science.gov (United States)

    Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi

    2011-07-01

    Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

  1. 1025t/h锅炉排烟温度高改造%Treatment of high exhaust gas temperature for 1025t / h boiler

    Institute of Scientific and Technical Information of China (English)

    刘勋川; 周胜利

    2011-01-01

    This paper briefly introduces the structure of 1025t/h boiler and its operation in Guizhou Qianbei Power Plant, aiming at its existing problems, such as high exhaust gas temperature and high desuperheating water flow, etc. By analyzing the boiler operation pa- rameters, this article presents some proposals to reduce exhaust gas temperature and boiler desuperheating water flow, and to improve the efficiency of the heating boiler. After the transformation, while receiving obvious effects, compared with the design value, it still has bigger difference. The author also puts forward views and opinions.%简要介绍了贵州西电黔北发电总厂1025t/h锅炉的结构及运行情况,针对锅炉排烟温度高、减温水流量大等问题。通过对锅炉运行参数的分析,提出了旨在降低锅炉排烟温度和减温水流量,提高了锅炉效率的受热面改造的建议。

  2. Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system

    International Nuclear Information System (INIS)

    Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

  3. Low exhaust temperature electrically heated particulate matter filter system

    Science.gov (United States)

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    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.

  4. Exhaust gas side corrosion of oil fired central heating boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1987-09-01

    While Swiss boiler producers aim primarily at achieving low exhaust gas temperatures, in our northern neighbouring country, lower boiler water temperatures are being set as favourite objectives to be met. The first method aims at reducing the exhaust gas losses, i.e. of the heat content of the exhaust gases; the second one aims at reducing service life losses (= losses in the off-air of the boiler). Flue-gas caused corrosion, however, sets practical limits to the energy-saving reduction of the exhaust gas and boiler water temperatures. To be able to define this practical limit more exactly is the main goal of this project which is supported by NEFF and which is carried out in cooperation with the Institute for Energy Engineering of the ETHZ (Professor P. Suter). In addition to this, however, the author also head to find out about sill inexplained cases of corrosion in boilers which are being operated correctly, i.e. with comparably high boiler water and exhaust gas temperatures.

  5. Effects of diluent admissions and intake air temperature in exhaust gas recirculation on the emissions of an indirect injection dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Abd-Alla, G.H.; Soliman, H.A.; Badr, O.A.; Abd-Rabbo, M.F. [Zagazig University, Cairo (Egypt). Shoubra Faculty of Engineering

    2001-05-01

    The operation of Diesel engines on gaseous fuels, commonly known as dual fuel engines, uses Diesel fuel as the pilot fuel and gaseous fuel (methane and sometimes propane in the present work) as the main fuel. The gaseous fuel was inducted in the intake manifold to mix with the intake air. The investigation was conducted on a high speed indirect injection (Ricardo-E6) dual fuel engine and was concerned with the effects of exhaust gas recirculation (EGR) on the dual fuel engine combustion and emissions, in particular, the effects of intake air temperature and diluent admissions (N{sub 2} and CO{sub 2}) on combustion and emissions. The use of diluents to displace oxygen (O{sub 2}) in the intake air resulted in a reduction in the O{sub 2} supplied to the engine, increased the inlet charge thermal capacity (thermal effect) and, potentially, CO{sub 2} and N{sub 2} participated in the combustion process (chemical effect). In a separate series of tests, the temperature of the engine inlet charge was raised gradually in order to simulate the effect of mixing hot EGR with the engine inlet gaseous fuel air mixture. It was found that the admission of diluents resulted in reductions in the exhaust oxides of nitrogen (NO{sub x}). Higher inlet charge temperature increases the exhaust NO{sub x} but reduces the unburned hydrocarbon emissions. Finally, when carbon dioxide was added to the inlet gaseous fuel air charge, large reductions in NO{sub x} were observed. (author)

  6. Sorption dehumidification of natural gas exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M.; Longo, G.A. (Padua Univ. (Italy)); Piccininni, F. (Politecnico di Bari (Italy). Ist. di Fisica Tecnica)

    1992-09-01

    The calorific value of natural gas can be fully utilized only if the water vapour in the exhaust gases is condensed. This can be achieved in condensing boilers. Another possibility is to dry the exhaust before discharge by sorption dehumidification. The sorbent can be regenerated directly by the boiler. The vapour developed in the regenerator can be condensed in a condenser with useful effect. Simulations given an efficiency higher than 97% with respect to the Gross Calorific value. (author).

  7. Exhaust gas treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Among global environmental problems, atmospheric pollution has been discussed since relatively old days, and various countermeasures have been taken, but recently in connection with acid rain, the efficient and economical treatment technology is demanded. As the denitration and desulfurization technology for the exhaust gas from the combustion of fossil fuel, the incineration of city trash and internal combustion engines, three is the treatment method by electron beam irradiation. By irradiating electron beam to exhaust gas, nitrogen oxides and sulfur oxides are oxidized to nitric acid and sulfuric acid, and by promoting the neutralization of these acids with injected alkali, harmless salts are recovered. This method has the merit that nitrogen oxides and surfur oxides can be removed efficiently with a single system. In this report, as for the exhaust gas treatment by electron beam irradiation, its principle, features, and the present status of research and development are described, and in particular, the research on the recent exhaust gas treatment in city trash incineration is introduced. This treatment method is a dry process, accordingly, waste water disposal is unnecessary. The reaction products are utilized as fertilizer, and waste is not produced. (K.I.)

  8. Low temperature operation and exhaust emission

    Energy Technology Data Exchange (ETDEWEB)

    Laurikko, J.

    1987-01-01

    Ambient temperature has the greatest effect on the exhaust emissions of internal combustion engines during the initial cold star and before the engine is fully warmed-up. Fuel evaporation is poor in a cold engine and the fuel-air mixture must be made richer to ensure that the engine weill start and be driveable. However, the combustion of a rich fuel-air mixture is incomplete because of the lack of oxygen, and the exhaust gases will contain an excessive amount of carbon monoxide (CO). The formation of nitrogen oxides (NO/sub x/) in a combustion engine is tied to high temperatures and oxygen concentrations. The conditions in a non-warmed engine using a rich fuel-air mixture are unfavourable for the formation of NO/sub x/ and the emission of NO/sub x/ may even diminish with falling ambient temperature. When the engine has reached its normal operating temperature the exhaust emissions are usually independent of the ambient temperature if the engine is equipped with intake air preheating that is sufficiently powerful. The reduction efficiency of a catalytic converter mainly depends on its operation temperature. Continuous operation at low temperatures may cause rapid poisoning of the converter. At low temperatures, carbon and other particles that do not burn collect on the active surface of the converter reducing its effectiveness.

  9. 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....

  10. 40 CFR 86.511-90 - 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. 86.511... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.511-90 Exhaust gas analytical system. (a) Schematic drawings. Figure F90-3 is a schematic drawing of the exhaust gas analytical system for analysis...

  11. 40 CFR 86.111-90 - 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. 86.111... Complete Heavy-Duty Vehicles; Test Procedures § 86.111-90 Exhaust gas analytical system. (a) Schematic drawings. Figure B90-7 is a schematic drawing of the exhaust gas analytical system for analysis...

  12. Integrated exhaust gas recirculation and charge cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ko-Jen

    2013-12-10

    An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.

  13. Second law analysis of a low temperature combustion diesel engine: Effect of injection timing and exhaust gas recirculation

    International Nuclear Information System (INIS)

    For diesel engines, low temperature combustion (LTC) with a high level of EGR and late injection becomes attractive because of its potential of simultaneous reduction of nitrogen oxides (NOx) and particulate matter (PM) emissions. However, detailed thermodynamic evaluations including second law analysis of the LTC are few. The current work employed an engine cycle simulation incorporating the second law of thermodynamics to evaluate the energy and exergy distribution of various processes in a low temperature combustion diesel engine. After validation with experimental data at eight operating conditions including four different EGR levels and two different injection timings, the model was used to evaluate the effect of EGR level and injection timing on the first and second law parameters. As EGR was increased, intake temperature and equivalence ratio increased. Results showed that for the case at 0% EGR level with conventional injection timing, about 30% of the fuel exergy was destructed during combustion processes, and as EGR level increased to 45% (intake temperature and equivalence ratio also increased), the combustion destructed exergy decreased to 20% of the fuel exergy. This was largely due to the related combustion temperature increase. For both conventional (−6.5° aTDC) and late (1.5° aTDC) injection timings, the percentage of exergy transfer through flows increases as EGR increases, which is attributed to the retarded ignition by increasing EGR. Other parameters such as energy and exergy transfer due to heat transfer, blow-by, and unburned fuel also were determined as a function of EGR level and injection timing. -- Highlights: ► Exergy destruction during combustion decreased as intake temperature increased. ► Both conventional and late injection timings (LTC cases) were examined. ► For conventional injection timings, the combustion efficiency remains constant as EGR increases. ► For late injections and high EGR, combustion was incomplete.

  14. Design of a high temperature chemical vapor deposition reactor in which the effect of the condensation of exhaust gas in the outlet is minimized using computational modeling

    Science.gov (United States)

    Yoon, Ji-Young; Geun Kim, Byeong; Nam, Deok-Hui; Yoo, Chang-Hyoung; Lee, Myung-Hyun; Seo, Won-Seon; Shul, Yong-Gun; Lee, Won-Jae; Jeong, Seong-Min

    2016-02-01

    Tetramethylsilane (TMS) was recently proposed as a safe precursor for SiC single crystal growth through high temperature chemical vapor deposition (HTCVD). Because the C content of TMS is much higher than Si, the exhaust gas from the TMS-based HTCVD contains large amounts of C which is condensed in the outlet. Because the condensed C close to the crystal growth front will influence on the thermodynamic equilibrium in the crystal growth, an optimal reactor design was highly required to exclude the effect of the condensed carbon. In this study, we report on a mass/heat transfer analysis using the finite element method (FEM) in an attempt to design an effective reactor that will minimize the effect of carbon condensation in the outlet. By applying the proposed reactor design to actual growth experiments, single 6H-SiC crystals with diameters of 50 mm were successfully grown from a 6H-SiC seed. This result confirms that the proposed reactor design can be used to effectively grow 6H-SiC crystals using TMS-based HTCVD.

  15. 40 CFR 86.1509 - Exhaust gas sampling system.

    Science.gov (United States)

    2010-07-01

    ... Regulations for Otto-Cycle Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum... Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test Procedures § 86.1509 Exhaust gas sampling system. (a) The exhaust gas sampling system shall transport...

  16. Boosting devices with integral features for recirculating exhaust gas

    Science.gov (United States)

    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.

  17. A bearing temperature stability control method and application of axial exhaust coal gas turbine machine%轴向排气型煤气透平的轴承温度稳定控制方法及应用

    Institute of Scientific and Technical Information of China (English)

    张亚军; 叶欣

    2012-01-01

    This paper concisely analyses the reasons for bearing temperature rise of the exhaust side which happened to radial intake and axial exhaust gas turbo-expanders. How to avoid the exhaust side's bearing temperature rise of the gas turbo-expanders is very important to guarantee the normal operation of turbine unit. This paper put forward through the control of the turbine exhaust temperature method of lateral bearing, making the process control function of TRT unit's automation system further improving.%简要分析了径向进气、轴向排气型煤气透平膨胀机的排气侧轴承温度增高的原因,如何避免煤气透平膨胀机排气侧支撑轴承温度的升高,对保证TRT机组的正常运行非常重要.通过该文提出的控制透平排气侧轴承温度升高的方法,使TRT机组自动化系统的控制功能更加完善.

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

    Science.gov (United States)

    Duffy, Kevin P.; Kieser, Andrew J.; Rodman, Anthony; Liechty, Michael P.; Hergart, Carl-Anders; Hardy, William L.

    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. 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.

  20. 40 CFR 1065.127 - Exhaust gas recirculation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  1. 30 CFR 7.102 - Exhaust gas cooling efficiency test.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING....102 Exhaust gas cooling efficiency test. (a) Test procedures. (1) Follow the procedures specified...

  2. 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... analytical system. The provisions of § 86.111-94 apply to this subpart, except that the NOX analyzer is optional. The exhaust gas analytical system must contain components necessary to determine...

  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...

  4. 30 CFR 36.26 - Composition of exhaust gas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Composition of exhaust gas. 36.26 Section 36.26... EQUIPMENT Construction and Design Requirements § 36.26 Composition of exhaust gas. (a) Preliminary engine... immediately at full load and speed. The preliminary liquid-fuel-injection rate shall be such that the...

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

    Science.gov (United States)

    Meisner, G. P.

    2013-03-01

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

  6. 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.)

  7. Exhaust gas recirculation for advanced diesel combustion cycles

    International Nuclear Information System (INIS)

    Highlights: • Analysis of the incremental (cycle-by-cycle) build-up of EGR. • Proposed one-step equations for transient/steady-state gas concentration estimation. • Defined an in-cylinder excess-air ratio to account for the recycled oxygen with EGR. • Demonstrated the use of intake oxygen as a reliable measure of EGR effectiveness. • Demonstrated the impact of engine load and intake pressure on EGR effectiveness. - Abstract: Modern diesel engines tend to utilize significantly large quantities of exhaust gas recirculation (EGR) and high intake pressures across the engine load range to meet NOx targets. At such high EGR rates, the combustion process and exhaust emissions tend to exhibit a marked sensitivity to small changes in the EGR quantity, resulting in unintended deviations from the desired engine performance characteristics (energy efficiency, emissions, stability). An accurate estimation of EGR and its effect on the intake dilution are, therefore, necessary to enable its application during transient engine operation or unstable combustion regimes. In this research, a detailed analysis that includes estimation of the transient (cycle-by-cycle) build-up of EGR and the time (engine cycles) required to reach the steady-state EGR operation has been carried out. One-step global equations to calculate the transient and steady-state gas concentrations in the intake and exhaust are proposed. The effects of engine load and intake pressure on EGR have been examined and explained in terms of intake charge dilution and in-cylinder excess-air ratio. The EGR analysis is validated against a wide range of empirical data that include low temperature combustion cycles, intake pressure and load sweeps. This research intends to not only formulate a clear understanding of EGR application for advanced diesel combustion but also to set forth guidelines for transient analysis of EGR

  8. Exhaust Gas Energy Recovery Technology Applications

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Robert M [ORNL; Szybist, James P [ORNL

    2014-01-01

    Exhaust waste heat recovery systems have the potential to significantly improve vehicle fuel economy for conventional and hybrid electric powertrains spanning passenger to heavy truck applications. This chapter discusses thermodynamic considerations and three classes of energy recovery technologies which are under development for vehicle applications. More specifically, this chapter describes the state-of-the-art in exhaust WHR as well as challenges and opportunities for thermodynamic power cycles, thermoelectric devices, and turbo-compounding systems.

  9. Automotive exhaust gas flow control for an ammonia–water absorption refrigeration system

    International Nuclear Information System (INIS)

    A considerable part of the energy generated by an automotive internal combustion engine is wasted as heat in the exhaust system. This wasted heat could be recovered and applied to power auxiliary systems in a vehicle, contributing to its overall energy efficiency. In the present work, the experimental analysis of an absorption refrigeration system was performed. The exhaust system of an automotive internal combustion engine was connected to the generator element of an absorption refrigeration system. The performance of the absorption refrigerator was evaluated as a function of the supplied heat. The use of a control strategy for the engine exhaust gas mass flow rate was implemented to optimize the system. Exhaust gas flow was controlled by step-motor actuated valves commanded by a microcontroller in which a proportional-integral control scheme was implemented. Information such as engine torque, speed, key temperatures in the absorption cycle, as well as internal temperatures of the refrigerator was measured in a transient regime. The results indicated that the refrigeration system exhibited better performance when the amount of input heat is controlled based on the temperature of the absorption cycle generator. It was possible to conclude that, by dynamically controlling the amount of input heat, the utilisation range of the absorption refrigeration system powered by exhaust gas heat could be expanded in order to incorporate high engine speed operating conditions. - Highlights: •An absorption refrigerator was driven by automotive exhaust gas heat. •A system for controlling the refrigeration system heat input was developed. •Excessive exhaust gas heat leads to ineffective operation of the refrigerator. •Control of refrigerator's generator temperature led to better performance. •The use of exhaust gas was possible for high engine speeds

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

    OpenAIRE

    Adhimoulame Kalaisselvane; Natarajan Alagumurthy; Krishnaraj Palaniradja; G Selvaraj Gunasegarane

    2010-01-01

    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...

  11. Methane oxidation over noble metal catalysts as related to controlling natural gas vehicle exhaust emissions

    International Nuclear Information System (INIS)

    Natural gas has considerable potential as an alternative automotive fuel. This paper reports on methane, the principal hydrocarbon species in natural-gas engine exhaust, which has extremely low photochemical reactivity but is a powerful greenhouse gas. Therefore, exhaust emissions of unburned methane from natural-gas vehicles are of particular concern. This laboratory reactor study evaluates noble metal catalysts for their potential in the catalytic removal of methane from natural-gas vehicle exhaust. Temperature run-up experiments show that the methane oxidation activity decreases in the order Pd/Al2O3 > Rh/Al2O3 > Pt/Al2O3. Also, for all the noble metal catalysts studied, methane conversion can be maximized by controlling the O2 concentration of the feedstream at a point somewhat rich (reducing) of stoichiometry

  12. Method for controlling exhaust gas heat recovery systems in vehicles

    Science.gov (United States)

    Spohn, Brian L.; Claypole, George M.; Starr, Richard D

    2013-06-11

    A method of operating a vehicle including an engine, a transmission, an exhaust gas heat recovery (EGHR) heat exchanger, and an oil-to-water heat exchanger providing selective heat-exchange communication between the engine and transmission. The method includes controlling a two-way valve, which is configured to be set to one of an engine position and a transmission position. The engine position allows heat-exchange communication between the EGHR heat exchanger and the engine, but does not allow heat-exchange communication between the EGHR heat exchanger and the oil-to-water heat exchanger. The transmission position allows heat-exchange communication between the EGHR heat exchanger, the oil-to-water heat exchanger, and the engine. The method also includes monitoring an ambient air temperature and comparing the monitored ambient air temperature to a predetermined cold ambient temperature. If the monitored ambient air temperature is greater than the predetermined cold ambient temperature, the two-way valve is set to the transmission position.

  13. 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.

  14. Exhaust gas energy recovery system of pneumatic driving automotive engine

    Institute of Scientific and Technical Information of China (English)

    Han Yongqiang; Sun Wenxu; Li Qinghua; Zhong Ming; Hao Wei; Du Wenchang

    2011-01-01

    Almost the same quantity to net output work of energy has been carried out and wasted by exhaust gas in typical automotive engine. Recovering the energy from exhaust gas and converting to mechanical energy will dramatically increase the heat efficiency and decrease the fuel consumption. With the increasing demand of fuel conservation, exhaust gas energy recovery technologies have been a hot topic. At present, many researches have been focused on heating or cooling the cab, mechanical energy using and thermo-electronic converting. Unfortunately, the complicated transmission of mechanical energy using and the depressed efficiency of thermo-electronic converting restrict their widely applying. In this paper, a kind of exhaust gas energy recovery system of pneumatic driving automotive engine, in which highly compressed air acts as energy storing and converting carrier, has been established. Pneumatic driving motor can produce moderate speed and high torque output, which is compatible for engine using. The feasibility has been certificated by GT-Power simulation and laboratory testes. The technologies about increasing recovery efficiency have been discussed in detail. The results demonstrated that the in parallel exhaust gas energy recovery system, which is similar to the compound turbo-charger structure can recovery 8 to 10 percent of rated power output. At last, a comprehensive system,which includes Rankine cycle based power wheel cycle unit etc. , has been introduced.

  15. Simulation of exhaust gas heat recovery from a spray dryer

    International Nuclear Information System (INIS)

    This study explored various alternatives in improving the energy utilization of spray drying process through the exhaust gas heat recovery. Extensible and user-friendly simulation code was written in Visual Basic for Applications within Microsoft Excel for this purpose. The effects of process parameters were analyzed on the energy efficiency and energy saving in the industrial-scale spray drying system with exhaust gas heat recovery in an air-to-air heat exchanger and in the system with partial recirculation of exhaust air. The spray dryer is equipped with an indirect heater for heating the drying air. The maximum gains of 16% in energy efficiency and 50% in energy saving were obtained for spray drying system equipped with heat exchanger for exhaust air heat recovery. In addition, 34% in energy efficiency and 61% in energy saving for system with recirculation of exhaust air in the present range of process parameters. The high energy efficiency was obtained during drying of large amount of dilute slurry. The energy saving was increased using the large amount of hot drying air. - Highlights: • We model industrial-scale spray drying process with the exhaust gas heat recovery. • We develop an Excel VBA computer program to simulate spray dryer with heat recovery. • We examine effects of process parameters on energy efficiency and energy saving. • High energy efficiency is obtained during drying of large amount of dilute slurry. • Energy saving is increased using the large amount of hot drying air

  16. Organic Rankine cycle for power recovery of exhaust flue gas

    International Nuclear Information System (INIS)

    To study the effects of different working fluids on the performance of organic Rankine cycle (ORC), three working fluids, a mixture that matches with heat source, a mixture that matches with heat sink and a pure working fluid, are selected in this paper. Thermodynamic models were built in Matlab together with REFPROP, with which, the physical properties of the selected working fluids can be acquired. Heat source of the ORC system is the exhaust flue gas of boiler in a 240 MW pulverized coal-fired power plant. Some indicators such as thermal efficiency, inlet temperature of expander, superheat degree, mass flow, volumetric flow, and exergy destruction distribution, as well as the influence of recuperator are studied. The analytical results show that the mixture that matches with heat sink has the greatest efficiency and the mixture that matches with heat source has the lowest superheat degree. The rate of heat exchanged in recuperator to that in evaporator has a maximum value with evaporating pressure. There exists no optimal working fluid for all indicators (thermal efficiency, heat exchanger area, mass flow and volumetric flow etc.). An appropriate working fluid should be chosen by taking both investment cost and power generating benefits into account. The cost-benefit ratio of the proposed ORC plant was evaluated either. - Highlights: • Three types of working fluids are selected for ORC using exhaust flue gas. • The mixture that matches with heat sink has the greatest efficiency. • The mixture that matches with heat source has the lowest superheat degree. • There does not exist a working fluid that satisfies all the indicators

  17. Novel catalytic converter for natural gas powered diesel engines to meet stringent exhaust emission regulations

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, M.; Mirosh, E.A. [Alternative Fuel Systems Inc. (Canada); Matros, Yu.S.; Bunimovich, G.A.; Strots, V.O. [Matros Technologies Inc. (United States); Sallamie, N.; Checkel, M.D. [Alberta Univ. (Canada); Windawi, H. [Johnson Matthey (United States)

    1998-12-31

    The implementation of stringent exhaust emission regulations has led to the development of natural gas powered dual fuel systems with electronic multiport injection. The high compression ratio of the baseline diesel engine was maintained to keep the high thermal efficiency of diesel cycles. The dual fuel system is mainly powered by natural gas and ignited by a diesel pilot. Extensive experimental results indicate that the diesel dual fuel system provides simultaneous reductions in NO{sub x} and particulate emissions. The system also has low exhaust THC and CO under heavy-duty operations. With the combined use of exhaust gas recirculation and catalytic converter, low emission operation has been extended to a larger range, from medium to full loads for all testing speeds. However, conventional converters exhibit poor conversion efficiency at low engine loads due to the low exhaust temperature levels. This leads to increased exhaust emissions during low load operations, especially for the non-reactive hydrocarbons, specifically, methane. To solve this problem, a novel automotive exhaust gas aftertreatment system - the reversing flow catalytic converter - has been developed. The prototype Reversing Flow Converter (RFC) consists of a diversion flow valve and a catalytic monolith converter. The diversion valve periodically re-directs the engine exhaust flow through the catalyst in alternative directions. The duration of flow in each direction is determined by engine operating conditions to obtain an ideal temperature profile along the axis of the monolith. The catalytic converter was designed to have high methane conversion efficiency. Associated techniques, such as retarding fuel injection, exhaust gas recirculation, and the variation of diesel pilot to natural gas ratio, can be used to raise exhaust temperature and bring the catalytic converter to light-off temperatures quicker. Engine dynamometer tests showed that CO conversion rate was above 95% and CH{sub 4

  18. A method for removal of CO from exhaust gas using pulsed corona discharge.

    Science.gov (United States)

    Li, X; Yang, L; Lei, Y; Wang, J; Lu, Y

    2000-10-01

    An experimental study of the oxidation of CO in exhaust gas from a motorcycle has been carried out using plasma chemical reactions in a pulsed corona discharge. In the process, some main parameters, such as the initial CO concentration, amplitude and frequency of pulses, residence time, reactor volume, and relative humidity (RH), as well as their effects on CO removal characteristics, were investigated. O3, which is beneficial to reducing CO, was produced during CO removal. When the exhaust gas was at ambient temperature, more than 80% CO removal efficiency was realized at an initial concentration of 288 ppm in a suitable range of the parameters. PMID:11288300

  19. An approach for exhaust gas energy recovery of internal combustion engine: Steam-assisted turbocharging

    International Nuclear Information System (INIS)

    Highlights: • The calculation method for SAT engine was developed and introduced. • SAT can effectively promote the low-speed performances of IC engine. • At 1500 r/min, intake pressure reaches target value and torque is increased by 25%. • The thermal efficiency of SAT engine only has a slight increase. - Abstract: An approach for IC engine exhaust gas energy recovery, named as steam-assisted turbocharging (SAT), is developed to assist the exhaust turbocharger. A steam generating plant is coupled to the exhaust turbocharged engine’s exhaust pipe, which uses the high-temperature exhaust gas to generate steam. The steam is injected into turbine inlet and used as the supplementary working medium for turbine. By this means, turbine output power and then boosting pressure can be promoted due to the increase of turbine working medium. To reveal the advantages and energy saving potentials of SAT, this concept was applied to an exhaust turbocharging engine, and a parameter analysis was carried out. Research results show that, SAT can effectively promote the low-speed performances of IC engine, and make the peak torque shift to low-speed area. At 1500 r/min, the intake gas pressure can reach the desired value and the torque can be increased by 25.0% over the exhaust turbocharging engine, while the pumping mean effective pressure (PMEP) and thermal efficiency only have a slight increase. At 1000 r/min, the improvement of IC engine performances is very limited due to the low exhaust gas energy

  20. 40 CFR 86.111-94 - Exhaust gas analytical system.

    Science.gov (United States)

    2010-07-01

    ...(a) and 1 CFR part 51. (B) Copies may be inspected at U.S. EPA, OAR, 401 M St., SW., Washington, DC... 40 CFR 1065.275 for the determination of N2O (required for 2015 and later model year vehicles). A... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas analytical system....

  1. Estimating IC engine exhaust gas lambda and oxygen from the response of a universal exhaust gas oxygen sensor

    International Nuclear Information System (INIS)

    Universal exhaust gas oxygen sensors (UEGOs) are in widespread use in internal combustion engines where they are used to measure lambda (the non-dimensional air–fuel ratio) and oxygen concentration (XO2). The sensors are used on production engines and for research and development. In a previous paper, a model of the UEGO sensor was presented, based on a solution of the Stefan–Maxwell equations for an axisymmetric geometry, and it was shown that for a known gas composition, predictions of the sensor response agreed well with experiment. In the present paper, the more ‘practical’ problem is addressed: how well can such a model predict λ and XO2 based on the sensor response? For IC engine applications, a chemistry model is required in order to predict λ, and such a model is also desirable for an accurate prediction of XO2. A fast (matrix exponential) method of solving the Stefan–Maxwell equations is also introduced, which offers the possibility of a near real-time computation of λ and XO2, with application, for example, to bench instruments. Extensive results are presented showing how the interpretation of the UEGO response may be compromised by uncertainties. These uncertainties may relate not only to the sensor itself, such as temperature, pressure and mean pore diameter, but also the chemistry model. (paper)

  2. 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.

  3. 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.

  4. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Thomas R.

    2009-12-31

    This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

  5. Electron beam treatment of exhaust gas with high NOx concentration

    International Nuclear Information System (INIS)

    Simulated exhaust gases with a high NOx concentration, ranging from 200 to 1700 ppmv, were irradiated by an electron beam from an accelerator. In the first part of this study, only exhaust gases were treated. Low NOx removal efficiencies were obtained for high NOx concentrations, even with high irradiation doses applied. In the second part of study, gaseous ammonia or/and vapor ethanol were added to the exhaust gas before its inlet to the plasma reactor. These additions significantly enhanced the NOx removal efficiency. The synergistic effect of high SO2 concentration on NOx removal was observed. The combination of electron beam treatment with the introduction of the above additions and with the performance of irradiation under optimal parameters ensured high NOx removal efficiency without the application of a solid-state catalyst. (paper)

  6. 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.

  7. 75 FR 82040 - Notice of Public Meeting on the International Maritime Organization Guidelines for Exhaust Gas...

    Science.gov (United States)

    2010-12-29

    ... Exhaust Gas Cleaning Systems for Marine Engines To Comply with Annex VI to MARPOL 73/78 AGENCY: Coast... meeting on the International Maritime Organization guidelines for exhaust gas cleaning systems for marine...-543 policy letter 09-01 that provide guidance for exhaust gas cleaning systems under MARPOL Annex...

  8. High exhaust temperature, zoned, electrically-heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    2015-09-22

    A system includes a particulate matter (PM) filter, an electric heater, and a control circuit. The electric heater includes multiple zones, which each correspond to longitudinal zones along a length of the PM filter. A first zone includes multiple discontinuous sub-zones. The control circuit determines whether regeneration is needed based on an estimated level of loading of the PM filter and an exhaust flow rate. In response to a determination that regeneration is needed, the control circuit: controls an operating parameter of an engine to increase an exhaust temperature to a first temperature during a first period; after the first period, activates the first zone; deactivates the first zone in response to a minimum filter face temperature being reached; subsequent to deactivating the first zone, activates a second zone; and deactivates the second zone in response to the minimum filter face temperature being reached.

  9. Temperature optimisation of a diesel engine using exhaust gas heat recovery and thermal energy storage (Diesel engine with thermal energy storage)

    OpenAIRE

    Kauranen, Pertti; Elonen, Tuomo; Wikström, Lisa; Heikkinen, Jorma; Laurikko, Juhani

    2009-01-01

    Abstract Modern automotive diesel engines are so energy efficient that they are heating up slowly and tend to run rather cold at subzero temperatures. The problem is especially severe in mail delivery operations where the average speed is low and the drive cycle includes plenty of idling. The problem is typically solved by adding a diesel fuelled additional engine heater which is used for the preheating of the engine during cold start and additional heating of the engine if the coo...

  10. 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.

  11. An assessment of consistence of exhaust gas emission test results obtained under controlled NEDC conditions

    Science.gov (United States)

    Balawender, K.; Jaworski, A.; Kuszewski, H.; Lejda, K.; Ustrzycki, A.

    2016-09-01

    Measurements concerning emissions of pollutants contained in automobile combustion engine exhaust gases is of primary importance in view of their harmful impact on the natural environment. This paper presents results of tests aimed at determining exhaust gas pollutant emissions from a passenger car engine obtained under repeatable conditions on a chassis dynamometer. The test set-up was installed in a controlled climate chamber allowing to maintain the temperature conditions within the range from -20°C to +30°C. The analysis covered emissions of such components as CO, CO2, NOx, CH4, THC, and NMHC. The purpose of the study was to assess repeatability of results obtained in a number of tests performed as per NEDC test plan. The study is an introductory stage of a wider research project concerning the effect of climate conditions and fuel type on emission of pollutants contained in exhaust gases generated by automotive vehicles.

  12. Effect of exhaust gas recirculation on diesel engine nitrogen oxide reduction operating with jojoba methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Saleh, H.E. [Mechanical Power Department, Faculty of Engineering, Mattaria, Helwan University, 9 k Eltaaweniat, Nasr Road, P.O. Box 11718, Cairo (Egypt)

    2009-10-15

    Jojoba methyl ester (JME) has been used as a renewable fuel in numerous studies evaluating its potential use in diesel engines. These studies showed that this fuel is good gas oil substitute but an increase in the nitrogenous oxides emissions was observed at all operating conditions. The aim of this study mainly was to quantify the efficiency of exhaust gas recirculation (EGR) when using JME fuel in a fully instrumented, two-cylinder, naturally aspirated, four-stroke direct injection diesel engine. The tests were carried out in three sections. Firstly, the measured performance and exhaust emissions of the diesel engine operating with diesel fuel and JME at various speeds under full load are determined and compared. Secondly, tests were performed at constant speed with two loads to investigate the EGR effect on engine performance and exhaust emissions including nitrogenous oxides (NO{sub x}), carbon monoxide (CO), unburned hydrocarbons (HC) and exhaust gas temperatures. Thirdly, the effect of cooled EGR with high ratio at full load on engine performance and emissions was examined. The results showed that EGR is an effective technique for reducing NO{sub x} emissions with JME fuel especially in light-duty diesel engines. With the application of the EGR method, the CO and HC concentration in the engine-out emissions increased. For all operating conditions, a better trade-off between HC, CO and NO{sub x} emissions can be attained within a limited EGR rate of 5-15% with very little economy penalty. (author)

  13. Treating exhaust gas from a pressurized fluidized bed reaction system

    Science.gov (United States)

    Isaksson, Juhani; Koskinen, Jari

    1995-01-01

    Hot gases from a pressurized fluidized bed reactor system are purified. Under superatmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a flitrate cake on the surface of the separator, and a reducing agent--such as an NO.sub.x reducing agent (like ammonia), is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1-20 cm/s) during passage of the gas through the filtrate cake while at superatmospheric pressure. Separation takes place within a distinct pressure vessel the interior of which is at a pressure of about 2-100 bar, and-introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine).

  14. Evaluation of the necessity of exhaust gas recirculation employment for a methanol/diesel reactivity controlled compression ignition engine operated at medium loads

    International Nuclear Information System (INIS)

    Highlights: • Methanol fraction considerably affected the engine performance. • Exhaust gases had little effect on fuel efficiency at a fixed ignition timing. • Good performance was obtained without exhaust gases at low initial temperature. • The introduction of exhaust gases was essential when initial temperature is high. - Abstract: Three-dimensional computational fluid dynamics simulation was conducted to investigate the improvement of engine performance by managing exhaust gas recirculation rate and methanol fraction in a methanol/diesel reactivity controlled compression ignition engine. By defining fuel efficiency and ringing intensity as the restricted boundaries, the operating ranges of exhaust gas recirculation rate and methanol fraction under various initial temperatures were determined to simultaneously achieve high fuel economy and avoid engine knock. The results indicated that the fuel efficiency and ringing intensity were dominantly affected by the combustion phasing, and they was nearly insensitive to the variations of exhaust gas recirculation rate and initial temperature at a constant combustion phasing. The necessity of exhaust gas recirculation employment at medium loads was dependent on the level of initial temperature. When initial temperature was less than the critical value (380 K in this study), optimal engine performance could be achieved by only adopting high methanol fraction without introducing exhaust gas recirculation. Once initial temperature was beyond the critical value, exhaust gas recirculation was imperative to avoid excessive ringing intensity. Through simultaneously optimizing methanol fraction and exhaust gas recirculation rate, the combined strategy exhibited more advantages in fuel efficiency, nitrogen oxides, and ringing intensity under a wide range of initial temperature

  15. Exhaust Gas Recirculation in Gas Turbines for Reduction of CO2 Emissions; Combustion Testing with Focus on Stability and Emissions

    Directory of Open Access Journals (Sweden)

    Johan E. Hustad

    2005-12-01

    Full Text Available Exhaust gas recirculation can be applied with the intention of reducing CO2 emissions. When a fraction of the exhaust gas is injected in the entry of a gas turbine, the amount of CO2 in the exhaust gas not being recirculated will be higher and less complicated to capture. However, with this change in combustion air composition, especially the reduced concentration of oxygen, the combustion process will be affected. The lower oxygen concentration decreases the stability and the increased amount of CO2, H2O and N2 will decrease the combustion temperature and thus, the NOx emissions. Testing has been performed on a 65 kW gas turbine combustor, to investigate the effect of adding N2, CO2 and O2 in the combustion process, with focus on stability and emissions of NOx. Results show that adding N2 and CO2 decreases the NOx emissions, whereas O2 addition increases the NOx emissions. The tests have been performed both in a diffusion flame (pilot burner and a premixed flame (main burner, and for additives being injected with the fuel or with the air stream. Addition into the fuel stream is proven to affect the NOx emissions the most. The stability limits of the flames are indicated with respect to mass-based additive-to-fuel ratios.

  16. Measurement of Gas-phase Acids in Diesel Exhaust

    Science.gov (United States)

    Wentzell, J. J.; Liggio, J.; Li, S.; Vlasenko, A. L.; Staebler, R. M.; Brook, J.; Lu, G.; Poitras, M.; Chan, T.

    2012-12-01

    Gas-phase acids were measured using chemical ionization mass spectrometry (CIMS) as part of the Diesel Engine Emission Research Experiment (DEERE). The CIMS technique, utilizing acetate ion (CH3COO-) as a reagent ion, proved to be a rapid (measurements on the order of seconds) and sensitive (several counts/pptv) method of quantifying the acid emissions. Diluted diesel exhaust measurements were made from a Constant Volume Sampling dilution tunnel using a light duty (1.9L turbocharged Volkswagen Jetta TDI) diesel engine equipped with an OEM diesel oxidation catalyst and exhaust gas recirculation, mounted on an engine dynamometer. Acids measured included isocyanic, nitrous, nitric, propionic and sum of lactic and oxalic, as well as other unidentified compounds. Complimentary measurements of CO, CO2, Total Hydrocarbon (THC), and NOx, were also performed. Several engine modes (different engine rpm and torque outputs) at steady state were examined to determine their effect on acid emissions. Emission rates with respect to NOx and fuel based emission factors were determined. Measurements of HONO fuel emission factors agree well with real-world measurements within a traffic tunnel.1 The first estimate of isocyanic acid emission factors from a diesel engine is reported, and suggests that the emission of this highly toxic compound in diesel exhaust should not be ignored. 1. Kurtenbach, R., Becker, K. H., Gomes, J. A. G., Kleffmann, J.,Lorzer, J. C., Spittler, M., Wiesen, P., Ackermann, R., Geyer, A.,and Platt, U.: Investigations of emissions and heterogeneous formation of HONO in a road traffic tunnel, Atmos. Environ., 35, 3385-3394, doi:10.1016/S1352-2310(01)00138-8, 2001.

  17. Steady-state modelling of the universal exhaust gas oxygen (UEGO) sensor

    International Nuclear Information System (INIS)

    The universal exhaust gas oxygen (UEGO) sensor is a well-established device which was developed for the measurement of relative air fuel ratio in internal combustion engines. There is, however, little information available which allows for the prediction of the UEGO's behaviour when exposed to arbitrary gas mixtures, pressures and temperatures. Here we present a steady-state model for the sensor, based on a solution of the Stefan–Maxwell equation, and which includes a momentum balance. The response of the sensor is dominated by a diffusion barrier, which controls the rate of diffusion of gas species between the exhaust and a cavity. Determination of the diffusion barrier characteristics, especially the mean pore size, porosity and tortuosity, is essential for the purposes of modelling, and a measurement technique based on identification of the sensor pressure giving zero temperature sensitivity is shown to be a convenient method of achieving this. The model, suitably calibrated, is shown to make good predictions of sensor behaviour for large variations of pressure, temperature and gas composition. (paper)

  18. 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)

  19. Inlet Exhaust Gas Temperature Condition for a Burner-type DPF at the Low and Moderate Load Steady State%喷油助燃再生DPF过滤体入口废气温度条件研究

    Institute of Scientific and Technical Information of China (English)

    伏军; 龚金科; 吴钢; 余明果; 吁璇; 张文强

    2011-01-01

    阐述了DPF喷油助燃再生的工作原理,在考虑过滤体内沉积微粒氧化反应次模型的基础上,以壁流式蜂窝陶瓷过滤体为研究对象,建立柴油机稳态工况下过滤体人口孔道的再生简化模型.考虑到柴油机中小负荷排气富氧条件,通过无量纲化,结合DPF的排气背压模型,得到了喷油助燃再生DPF时过滤体入口端所需的温度条件.试验表明,以该条件获得的理论过滤体入口废气温度所对应的喷油率来调节燃烧器功率可顺利实现DPF的再生过程,为DPF喷油助燃再生系统的设计提供了一定的理论依据.%The operation principle of a burner-type diesel particulate filter was presented. Taking the subordinate oxidation reaction model into consideration, and taking the honeycomb wall-flow ceramic monolith filter as a research object, the simplified regeneration model in the single inlet channel of the filter was built at the steady state of the diesel engine. Based on the non-dimensionalization and the exhaust back-pressure model of DPF, the required temperature condition of the inlet exhaust for the burner-type DPF was obtained. The tests showed that the DPF regeneration could be smoothly completed by the burner power adjustment according to the oil spray rate correspond to the theoretical inlet exhaust temperature. It provided a definite theory basis to the design of the burner-type DPF.

  20. 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...

  1. 40 CFR 92.114 - Exhaust gas and particulate sampling and analytical system.

    Science.gov (United States)

    2010-07-01

    ... sampling of the particulate material may take place (Figure B114-3 of this section) at this point. (i)(A... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Exhaust gas and particulate sampling... Procedures § 92.114 Exhaust gas and particulate sampling and analytical system. (a) General. (1)...

  2. Neuralfussy multivariable control applied to the control of velocity, power, and exhaust gas temperature of a turbo gas unit; Control neurodifuso multivariable aplicado al control de velocidad, potencia y temperatura de gases de escape de una unidad turbogas

    Energy Technology Data Exchange (ETDEWEB)

    Segura Ozuna, Victor Octavio

    2004-11-15

    The electric power demand in Mexico has forced to the electric sector to be in a constant search of methods and systems that, among other objectives, improve the operation of the generating power stations of electric power continually. As part of their mission, the Electrical Research Institute (IIE) has promoted and leaning the applied research and the technological development to improve the indexes of security, readiness, dependability, efficiency and durability of central generating by means of the development and the installation of big digital systems of information and control. At the present time, inside the scheme of electric power generation, the gas turbine (UTG) represent 7% of the generation of the national electric sector [1]. These units have become the dominant way of the new electric generation in the U.S, either in simple cycle or combined. The above-mentioned, is attributable at less installation cost for generated kilowatt, to the shortest construction programs, at first floor levels of emission of pollutants and competitive operation costs. The control system of the gas turbine is based on conventional control algorithms of the type PI [2]. This control scheme is dedicated for regulation tasks and rejection to interferences, and it doesn't stop pursuit of reference points. The controllers act all on a control valve, that which represents a strong interaction among the same ones, for example an adjustment in the parameters of the algorithm of the digital PI of temperature, it can improve their acting but it can also affect the acting of the speed control or that of power. The gas turbine presents a non lineal behavior and variant in the time, mainly in the starting stage where several important disturbances are presented. At the moment, the controllers used in the scheme of control of the turbines are lineal, which are syntonized for a specific operation point and they are conserved this way by indefinite time. In this thesis the

  3. Temperature monitoring of vehicle engine exhaust gases under vibration condition using optical fibre temperature sensor systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, W Z [School of Eng. and Math. Sciences, City University, Northampton Square, London EC1V 0HB (United Kingdom); Suna, T [School of Eng. and Math. Sciences, City University, Northampton Square, London EC1V 0HB (United Kingdom); Grattana, K T V [School of Eng. and Math. Sciences, City University, Northampton Square, London EC1V 0HB (United Kingdom); Shen, Y H [Department of Physics, Zhejiang University, Hangzhou, China, 310027 (China); Wei, C L [Department of Elec. Eng. and Electronics, University of Liverpool, Brownlow Hill, Liverpool, L69 3GJ (United Kingdom); Al-Shamma' a, A I [Department of Elec. Eng. and Electronics, University of Liverpool, Brownlow Hill, Liverpool, L69 3GJ (United Kingdom)

    2006-07-15

    Two optical approaches, comprising and contracting both the fluorescence decay lifetime and the fibre Bragg grating (FBG) methods, were developed and evaluated for temperature monitoring of exhaust gases for use on a vehicle engine. The FBGs used in the system were written into specially designed Bi-Ge co-doped photosensitive fibres, to enable them to sustain high temperatures to over 800{sup 0}C, which is far beyond that of FBGs written into most commercial photosensitive fibres. The sensors were subjected to a range of vibration tests, as a part of an optical exhaust monitoring network under development, and results from the test carried out are reported.

  4. Removal of methane from compressed natural gas fueled vehicle exhaust

    International Nuclear Information System (INIS)

    The objective of this paper is to investigate the modes of methane (CH4) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the oxidation of methane with oxygen as well as nitric oxide contributes to its removal under net reducing conditions. The steam reforming reaction does not significantly contribute to the removal of methane. The methane conversions under net reducing conditions are higher than those observed under net oxidizing conditions. The study shows that the presence of carbon monoxide in the feed gas leads to a gradual decrease in the methane conversion with increasing redox ratio, under net oxidizing conditions. a minimum in methane conversion is observed at a redox ratio of 0. 8. The higher activity for the methane-oxygen reaction resulting from a lowering in the overall oxidation state of palladium and the contribution of the methane-nitric oxide reaction toward the removal of CH4 appear to account for the higher CH4 conversions observed under net reducing conditions

  5. 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.

  6. Turbine gas temperature measurement and control system

    Science.gov (United States)

    Webb, W. L.

    1973-01-01

    A fluidic Turbine Inlet Gas Temperature (TIGIT) Measurement and Control System was developed for use on a Pratt and Whitney Aircraft J58 engine. Based on engine operating requirements, criteria for high temperature materials selection, system design, and system performance were established. To minimize development and operational risk, the TIGT control system was designed to interface with an existing Exhaust Gas Temperature (EGT) Trim System and thereby modulate steady-state fuel flow to maintain a desired TIGT level. Extensive component and system testing was conducted including heated (2300F) vibration tests for the fluidic sensor and gas sampling probe, temperature and vibration tests on the system electronics, burner rig testing of the TIGT measurement system, and in excess of 100 hours of system testing on a J58 engine. (Modified author abstract)

  7. Analysis of the reusability of the energy of the exhaust gas from the calciner for the production of carbon

    International Nuclear Information System (INIS)

    A calciner is used to produce carbon from anthracite coal. In its working process, a significant amount of energy is lost through its exhaust gas. How much energy can be recovered from the exhaust gas becomes important. To answer this question a method to determine the mass flow rate and the composition of the exhaust gas from a calciner is developed, and a combustion model based on well-stirred reactor is used to obtain the suitable combustor parameters and the amount of the chemical energy which can be released in combustion. As an example to verify the method and the model, the energy utilization ratio of a calciner with power of 1250 kW is investigated. The results show that the method can determine the mass flow rate and the composition of the exhaust gas, and the combustion model is suitable for obtaining reasonable results in determining the volume and the heat duty of the combustor, the air–fuel ratio, and the amount of the chemical energy released. For a calciner with power of 1250 kW, when the temperature of the tail gas after combustion reaches to 135 °C, the energy utilization ratio of the calciner is calculated to be around 77%. - Highlights: • A method obtaining the mass balance of exhaust gas from calciner is reported. • A combustion model obtaining combustion behavior of the exhaust gas is reported. • Determining the energy utilization ratio of a typical calciner is demonstrated. • The energy utilization ratio of a typical calciner is about 77%

  8. Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor

    OpenAIRE

    Ralf Moos; Kerstin Wiesner; Diana Biskupski; Andrea Geupel; Maximilian Fleischer

    2009-01-01

    Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electroche...

  9. Dual-purpose power plants, experiences with exhaust gas purification plants

    International Nuclear Information System (INIS)

    From 1984 to 1988, the research and development project ''pollutant reduction for exhaust gases from heat production systems'' sponsored by the Federal Ministry of Research and Technology (BMFT) has been carried out by TUeV in Bavaria. This project was to show the state of exhaust gas technology for small and medium-sized plants (boilers and motoric heat generators). When publishing the final report, no positive balance could be given. Based on the results, the succession project ''Exhaust gas purification plants in field test'' (ARIF) has been started. This project has the following objectives: -Measuring technical investigation of the exhaust gas purification of motoric driven heat generator systems in field test. - Suitability of hand measuring devices for emissions for a discontinuous control of the exhaust gas purification plat by the operator. - Control of new methods regarding pollutant reduction for motoric and conventional heat generators. (orig.)

  10. Laboratory Scale of Liquid Coal Fuel Combustion Process and Exhaust Gas Formation

    Directory of Open Access Journals (Sweden)

    Kartika K. Hendratna

    2010-01-01

    Full Text Available Problem statement: Much research of coal has been already undertaken to ascertain the possibilities of coal being used as substitute for heavy fuel oil in the transportation sector. The effects of using coal as transportation fuel to the environment must also be considered. This study will review several aspects of the coal oil combustion process including combustion behavior, flame stability, some emissions from exhaust gas; CO, NOx and the particulate matter in a well insulated laboratory scale furnace for more stable of combustion. Approach: New way for preparation for liquid coal oil steady combustion on a 2.75 m horizontal boiler with four annular segment tubes, a water jacket system and a system for measurement of water temperature inside was archived. Data was gained by applying liquid coal in the experiment. Detailed preparation and setting for steady combustion of coal oil and formation of the exhaust gas were discussed based on data sampling from four sample points in each centre of the angular tube segments. Results: Preparation for coal oil combustion is an important point in the successful of combustion. Heating coal fuel to than 100°C, heating the fuel line to the same temperature and providing enough air pressure for atomization of coal oil until 0.1 MPa allows coal fuel smoothly atomized in the semi gas phase. There was enough of air combustion via a blower with 4500 L min-1 of flow rate and a 24 L min-1 of water flow rate in the water jacket transforms the energy of the fuel to the heat. Uncolored of the exhaust gas and the physical inspection describes the completion of combustion. This result close-relates with the pollutants formation in the exhaust gas. Conclusion: By conducting a deep research process, there is a chance for the substitute of heavy fuel oil with liquid coal fuel with no special treatment needed in combustion process without ignoring the contribution of the combustion results as an environmental problem.

  11. Test procedures for measuring exhaust emissions from natural gas transmission engines

    International Nuclear Information System (INIS)

    This paper reports on the measurement of exhaust components from large natural gas transmission engines involves collection of the exhaust sample, transfer of the sample to the analytical instrumentation, measurement of individual component concentrations, and calculations of emission results in terms of mass, fuel specific, and brake specific rates. The major exhaust components measured include nitrogen oxides (NOx), total hydrocarbons (THC), carbon dioxide (CO2), carbon monoxide (CO), and oxygen (O2). Collection of the exhaust sample requires proper probe design and placement in the exhaust system. Transfer of the sample to the analytical instruments must maintain sample integrity from the point where the sample is removed from the exhaust stream to the point at which the sample enters the instrument for analysis. Various analytical techniques are used to measure the exhaust emission concentrations

  12. 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.)

  13. Development of exhaust gas treatment technologies for environment protection

    International Nuclear Information System (INIS)

    Full text: The emission of carbon dioxide (CO2) and other pollutants which result from burning fossil fuels has been identified as the major contributor to global warming and climate change. However, for the immediate term over the next 10 - 20 years at least, the world will continue to rely on fossil fuels as the source of primary energy. The challenge for the fossil fuel industry is to find cost-effective solutions that will reduce the release of CO2 and other pollutants into the atmosphere. The focus of this paper is on the ability to treat the exhaust gas from fossil fuel power plants in order to capture and store the CO2 and remove other pollutants such as SOx and NOx which are released in the atmosphere. In summary, capture/separation costs represent the largest financial impediment for this types of plants. Hence, efficient, cost-effective capture/separation technologies will need to be developed in order to allow their large-scale use. (authors)

  14. Influence of Ambient Temperature on the CO2 Emitted With Exhaust Gases of Gasoline Vehicles

    Science.gov (United States)

    Chainikov, D.; Chikishev, E.; Anisimov, I.; Gavaev, A.

    2016-08-01

    This article focuses on the regulation of CO2 emitted in the exhaust gases of gasoline vehicles. Based on comparing the world practices of restrictive measures on greenhouse gas emissions with Russian legislation, we conclude that there is a need to adjust the limits of CO2 emission taking into account the negative impact of ambient temperature on CO2 emission. The climatic conditions of many countries stipulate the use of vehicles in temperatures below zero. At the same time, the existing regulations fully take into account the temperature features of the various countries, which casts doubt on the existence of uniform emission standards for all countries. Here, we conduct an experiment on one of the most popular cars in Russia: the Mitsubishi Lancer 9. We establish that lower temperatures are correlated with larger concentrations of CO2 in the exhaust gases. We draw a conclusion about the need to account for the actual operating conditions when establishing limit values on CO2 emissions of vehicles.

  15. 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

    of recovering some of the waste heat from the exhaust gas. This heat is converted into electrical energy used on-board instead of using auxiliary engines. Exhaust Gas Recirculation (EGR) systems, are recirculating a part of the exhaust gas through the engine combustion chamber to reduce emissions. WHRS combined......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...

  16. Evaluating tractor performance and exhaust gas emissions using biodiesel from cotton seed oil

    International Nuclear Information System (INIS)

    Alternative fuels for diesel engines, such as biodiesel, have attracted much attention recently due to increasing fuel prices and the imperative to reduce emissions. The exhaust gas emissions from tractors and other agricultural machinery make a significant contribution to these emissions. The use of biodiesel in internal combustion engines (ICE) has been reported to give comparable performance to conventional diesel (CD), but with generally lower emissions. There is however, contradictory evidence of NO emissions being both higher and lower from the use of biodiesel. In this work, agriculture tractor engine performance and its emission using both CD and biodiesel from cotton seed oil (CSO-B20) mixed at a 20% blend ration has been evaluated and compared. The PTO test results showed comparable exhaust emissions between CD and CSO-B20. However, the use of CSO-B20 led to reductions in the thermal efficiency and exhaust temperature and an increase in the brake specific fuel consumption (BSFC), when compared to CD.

  17. Evaluation of SI engine exhaust gas emissions upstream and downstream of the catalytic converter

    Energy Technology Data Exchange (ETDEWEB)

    Silva, C.M.; Costa, M.; Farias, T.L. [Mechanical Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais, 1049-001 Lisbon (Portugal); Santos, H. [Escola Superior de Tecnologia e Gestao, Instituto Politecnico de Leiria, Leiria (Portugal)

    2006-11-15

    The conversion efficiency of a catalytic converter, mounted on a vehicle equipped with a 2.8l spark ignition engine, was evaluated under steady state operating conditions. The inlet and outlet chemical species concentration, temperature and air fuel ratio (A/F) were measured as a function of the brake mean effective pressure (BMEP) and engine speed (rpm). Oil temperature, coolant temperature, brake power and spark advance were also monitored. In parallel, a mathematical model for the catalytic converter has been developed. The main inputs of the model are the temperature, flow rate, chemical species mass flow and local A/F ratio as measured at the catalyst inlet section. The main conclusions are: (i) the exhaust gas and substrate wall temperatures at the catalyst outlet increase with BMEP and rpm; (ii) the HC conversion efficiency increases with the value of BMEP up to a maximum beyond which it decreases; (iii) the CO conversion efficiencies typically increase with BMEP; (iv) the NO{sub x} conversion efficiency remains nearly constant regardless of BMEP and rpm; (v) except for idle, the NO{sub x} conversion efficiency is typically the highest, followed in turn by the CO and HC conversion efficiencies; (vi) conversion efficiencies are lower for idle conditions, which can be a problem under traffic conditions where idle is a common situation; (vii) regardless of rpm and load, for the same flow rate the conversion efficiency is about the same; (viii) the model predictions slightly over estimate the exhaust gas temperature data at the catalyst outlet section with the observed differences decreasing with BMEP and engine speed; (ix) in general, the model predictions of the conversion efficiencies are satisfactory. (author)

  18. 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.

  19. 40 CFR 91.420 - CVS concept of exhaust gas sampling system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false CVS concept of exhaust gas sampling system. 91.420 Section 91.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... mixing tunnel into which the engine exhaust and dilutant (background) air are dumped; a dilute...

  20. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false CVS concept of exhaust gas sampling system. 90.420 Section 90.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... consist of: a mixing tunnel into which the engine exhaust and dilutant (background) air are dumped;...

  1. 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...

  2. 40 CFR 86.1310-90 - Exhaust gas sampling and analytical system; diesel engines.

    Science.gov (United States)

    2010-07-01

    ... deflections or voltage output of analyzers with non-linear calibration curves shall be converted to... system; diesel engines. 86.1310-90 Section 86.1310-90 Protection of Environment ENVIRONMENTAL PROTECTION... Particulate Exhaust Test Procedures § 86.1310-90 Exhaust gas sampling and analytical system; diesel...

  3. Simulation and evaluation of a CCHP system with exhaust gas deep-recovery and thermoelectric generator

    International Nuclear Information System (INIS)

    Highlights: • Exhaust gas deep-recovery and thermoelectric generator are applied in CCHP system. • Electric output of TEG changes from 0.231 kW to 1.18 kW. • Total recoverable waste heat increases by 13–16%. • ESR, CSR and PEE are improved to 0.304, 0.417, and 0.944, respectively. • The total investment increment of system is about 11%. - Abstract: Combined cooling, heating and power (CCHP) systems are thought to be highly efficient in energy utilization. But there are still potentials to further improve system performance. This work proposed a CCHP system based on internal combustion engine (ICE) for power generation, refrigeration and domestic hot water production. Thermoelectric generator (TEG) and condensing heat exchanger are applied to efficiently recover the exhaust gas waste heat of ICE. All the energy flows are designed based on energy cascading utilization principle. Basing on the test results of a 16 kW ICE, CCHP system characteristics are investigated by simulation from idling condition to full load condition. Especially, the part load performance of TEG and absorption chiller are simulated and discussed. The feasible operating zone of ICE and feed water flow rate are figured out to keep the domestic hot water temperature within a certain range. Results show that the primary energy efficiency of system can reach 0.944, thanks to the condensing heat recovery from exhaust gas. The primary energy saving ratio and cost saving ratio can reach 0.304 and 0.417, respectively. Considering some more equipment is incorporated, the total investment increment is about 11.1%

  4. Mutagenicity of diesel exhaust particle extracts: influence of driving cycle and environmental temperature.

    Science.gov (United States)

    Clark, C R; Dutcher, J S; Brooks, A L; McClellan, R O; Marshall, W F; Naman, T M

    1982-01-01

    General Motors and Volkswagen diesel passenger cars (1980 and 1981 model year) were operated on a climate controlled chassis dynomometer and the particulate portion of the exhaust was collected on high volume filters. Dichloromethane extracts of the exhaust particles (soot) collected while the cars were operated under simulated highway, urban and congested urban driving cycles were assayed for mutagenicity in Salmonella strains TA-98 and TA-100. Driving pattern did not significantly influence the mutagenic potency of the exhaust particle extracts or estimates of the amount of mutagenicity emitted from the exhaust despite large differences in particle emission rates and extractable fraction of the particles. Mutagenicity of extracts of exhaust particles collected while the vehicles were operated at test chamber temperatures of 25, 50, 75 and 100 degrees F were also very similar. The results suggest that driving pattern and environmental temperature do not significantly alter the emission of genotoxic combustion products from the exhaust. PMID:6193022

  5. Mutagenicity of diesel exhaust particle extracts: influence of driving cycle and environmental temperature.

    Science.gov (United States)

    Clark, C R; Dutcher, J S; Brooks, A L; McClellan, R O; Marshall, W F; Naman, T M

    1982-01-01

    General Motors and Volkswagen diesel passenger cars (1980 and 1981 model year) were operated on a climate controlled chassis dynomometer and the particulate portion of the exhaust was collected on high volume filters. Dichloromethane extracts of the exhaust particles (soot) collected while the cars were operated under simulated highway, urban and congested urban driving cycles were assayed for mutagenicity in Salmonella strains TA-98 and TA-100. Driving pattern did not significantly influence the mutagenic potency of the exhaust particle extracts or estimates of the amount of mutagenicity emitted from the exhaust despite large differences in particle emission rates and extractable fraction of the particles. Mutagenicity of extracts of exhaust particles collected while the vehicles were operated at test chamber temperatures of 25, 50, 75 and 100 degrees F were also very similar. The results suggest that driving pattern and environmental temperature do not significantly alter the emission of genotoxic combustion products from the exhaust.

  6. Exhaust purification with on-board ammonia production

    Science.gov (United States)

    Robel, Wade J.; Driscoll, James Joshua; Coleman, Gerald N.

    2008-05-13

    A system of ammonia production for a selective catalytic reduction system is provided. The system includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream may be converted into ammonia.

  7. Gas separation process using membranes with permeate sweep to remove CO.sub.2 from gaseous fuel combustion exhaust

    Science.gov (United States)

    Wijmans Johannes G.; Merkel, Timothy C.; Baker, Richard W.

    2012-05-15

    A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.

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

    OpenAIRE

    Nielsen, Kræn V.; Blanke, Mogens; Vejlgaard-Laursen, Morten

    2015-01-01

    A nonlinear adaptive controller is proposed for the exhaust gas recirculation system on large two-stroke diesel engines. The control design is based on a control oriented model of the nonlinear dynamics at hand that incorporates fuel flow and turbocharger speed changes as known disturbances to the exhaust gas recirculation. The paper provides proof of exponential stability for closed loop control of the model given. Difficulties in the system include that certain disturbance levels will make ...

  9. Selection оf Parameters for System of Diesel Engine Exhaust Gas Recirculation

    Directory of Open Access Journals (Sweden)

    G. M. Kukharionok

    2014-01-01

    Full Text Available The paper presents research results of various methods for recirculation of diesel engine exhaust gases. An influence of recirculation parameters on economic and ecological diesel engine characteristics has been evaluated in the paper. The paper considers an influence of turbocharger configuration on the intensity of gas recirculation. Specific features of the recirculation system operation in dynamic modes have been shown in the paper. The paper provides recommendations for selection of a diesel engine exhaust gas recirculation system.

  10. 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....

  11. Design review report for the RMCS exhauster modifications for flammable gas tanks

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, J.E., Westinghouse Hanford

    1996-08-27

    This report documents the completion of the formal design review for the Rotary Mode Core Sampling (RMCS) Exhauster modifications for flammable gas tanks. The RMCS Exhauster modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to approve Engineering Change Orders and new drawings, at the 100% design completion state. The conclusion reached by the review committee was that the design was acceptable and efforts should continue toward fabrication and delivery.

  12. 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.

  13. 40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Exhaust gas sampling system; Otto... HIGHWAY VEHICLES AND ENGINES (CONTINUED) Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1309-90 Exhaust gas sampling system;...

  14. Exhaust gas recirculation – Zero dimensional modelling and characterization for transient diesel combustion control

    International Nuclear Information System (INIS)

    Highlights: • Zero-dimensional EGR model for transient diesel combustion control. • Detailed analysis of EGR effects on intake, cylinder charge and exhaust properties. • Intake oxygen validated as an operating condition-independent measure of EGR. • Quantified EGR effectiveness in terms of NOx emission reduction. • Twin lambda sensor technique for estimation of EGR/in-cylinder parameters. - Abstract: The application of exhaust gas recirculation (EGR) during transient engine operation is a challenging task since small fluctuations in EGR may cause larger than acceptable spikes in NOx/soot emissions or deterioration in the combustion efficiency. Moreover, the intake charge dilution at any EGR ratio is a function of engine load and intake pressure, and typically changes during transient events. Therefore, the management of EGR during transient engine operation or advanced combustion cycles (that are inherently less stable) requires a fundamental understanding of the transient EGR behaviour and its impact on the intake charge development. In this work, a zero-dimensional EGR model is described to estimate the transient (cycle-by-cycle) progression of EGR and the time (engine cycles) required for its stabilization. The model response is tuned to a multi-cylinder engine by using an overall engine system time-constant and shown to effectively track the transient EGR changes. The impact of EGR on the actual air–fuel ratio of the cylinder charge is quantified by defining an in-cylinder excess-air ratio that accounts for the oxygen in the recycled exhaust gas. Furthermore, a twin lambda sensor (TLS) technique is implemented for tracking the intake dilution and in-cylinder excess-air ratio in real-time. The modelling and analysis results are validated against a wide range of engine operations, including transient and steady-state low temperature combustion tests

  15. [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. PMID:25208369

  16. 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.

  17. Exhaust gas concentration of CNG fuelled direct injection engine at MBT timing

    International Nuclear Information System (INIS)

    Full text: This paper presents an experimental result of exhaust gas concentration of high compression engine fuelled with compressed natural gas (CNG) at maximum brake torque (MBT). The engine uses central direct injection (DI) technique to inject the CNG into the cylinder. The engine geometry bases on gasoline engine with 14:1 compression ratio and called CNGDI engine. The injectors are positioned within a certain degrees of spark plug location. The objective of the experiment is to study the influence and significant of MBT timing in CNGDI engine towards exhaust gases. The experimental tests were carried out using computer-controlled eddy-current dynamometer, which measures the CNGDI engine performance. At MBT region, exhaust gas concentration as such CO, HC, NOx, O2 and CO2, were recorded and analyzed during the test using the Horiba analyzer. A closed loop wide band lambda sensor has been mounted at the exhaust manifold to indicate the oxygen level during the exercise. (author)

  18. An analysis of the thermodynamic efficiency for exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB)

    International Nuclear Information System (INIS)

    This study presents fundamental research on the development of a new boiler that is expected to have a higher efficiency and lower emissions than existing boilers. The thermodynamic efficiency of exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB) was calculated using thermodynamic analysis and was compared with other boilers. The results show the possibility of obtaining a high efficiency when the temperature of the exhaust gas is controlled within 50–60 °C because water in the exhaust gas is condensed within this temperature range. In addition, the enthalpy emitted by the exhaust gas for the new boiler is smaller because the amount of condensed water is increased by the high dew-point temperature and the low exhaust gas temperature. Thus, the new boiler can obtain a higher efficiency than can older boilers. The efficiency of the EGR-CWR-WHR CB proposed in this study is 93.91%, which is 7.04% higher than that of existing CB that is currently used frequently. - Highlights: • The study presents the development of a new boiler expected to have a high efficiency. • Thermodynamic efficiency of EGR-CWR-WHR condensing boiler was calculated. • Efficiency of EGR-CWR-WHR CB is 93.91%, which is 7.04% higher than existing CB

  19. 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

  20. Research and Practice on Recover Boiler Waste Heat by Reduce the Exhaust Gas Temperature%降低锅炉排烟温度利用烟气余热的实践与理论研究

    Institute of Scientific and Technical Information of China (English)

    胡广涛; 岳益锋

    2012-01-01

    排烟温度偏高是国内电站锅炉普遍存在的问题,排烟温度较高时严重影响电厂的热经济性,因此,降低排烟温度对于节能降耗、提高锅炉的安全可高性具有重要的现实意义.通过煤粉炉改造实践和利用等效焓降法分析加装低压省煤器后的经济效益,结果表明低压省煤器系统不仅能降低锅炉机组排烟温度,而且能降低煤耗,提高锅炉的运行经济性,在电厂余热回收方面具有重要作用.%The over high exhaust smoke temperature ( EST) is a universal problem for power station boilers at present. When the EST exceeds over the design value very much, it affects the thermal economic efficiency of power stations, and it has a great meaning to decrease the EST for saving the energy, promoting safety and reliability of boilers. Through modificatory of 130 t/h pulverized coal - fired boiler and analysed economic by equivalent enthalpy drop method in low pressure economizer it has been found that the low - press economizer not only decreases the EST, bul also decreases the carbon - consumption,enhance the operation economy of boiler. It plays an important role in the remaining heat reclaiming in the power plant.

  1. Analysis of benefits of using internal exhaust gas recirculation in biogas-fueled HCCI engines

    International Nuclear Information System (INIS)

    Highlights: • The influence of EGR on combustion of biogas fueled HCCI was investigated. • The aim was to reduce intake temperature requirement by internal EGR. • Combustion products caused the delay of combustion in similar conditions. • Internal EGR enabled by negative valve overlap increased cylinder temperature. • This increase was not enough to significantly reduce the intake temperature. - Abstract: This paper describes a numerical study that analyzed the influence of combustion products (CP) concentration on the combustion characteristics (combustion timing and combustion duration) of a biogas fueled homogeneous charge compression ignition (HCCI) engine and the possibility of reducing the high intake temperature requirement necessary for igniting biogas in a HCCI engine by using internal exhaust gas recirculation (EGR) enabled by negative valve overlap (NVO). An engine model created in AVL Boost, and validated against experimental engine data, was used in this study. The results show, somewhat counter-intuitively, that when CP concentrations are increased the required intake temperature for maintaining the same combustion timing must be increased. When greater NVO is used to increase the in-cylinder CP concentration, the in-cylinder temperature does increase, but the chemical dilution influence of CP almost entirely counteracts this thermal effect. Additionally, it has been observed that with larger fractions of CP some instability of combustion in the calculation was obtained which indicates that the increase of internal EGR might produce some combustion instability

  2. Platform for a hydrocarbon exhaust gas sensor utilizing a pumping cell and a conductometric sensor.

    Science.gov (United States)

    Biskupski, Diana; Geupel, Andrea; Wiesner, Kerstin; Fleischer, Maximilian; Moos, Ralf

    2009-01-01

    Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga(2)O(3) or doped SrTiO(3) are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well. PMID:22423212

  3. Study on the combustion characteristics of a premixed combustion system with exhaust gas recirculation

    International Nuclear Information System (INIS)

    The boiler of a premixed combustion system with EGR (exhaust gas recirculation) is investigated to explore the potential for increasing thermal efficiency and lowering pollutant emissions. To achieve this purpose, a thermodynamic analysis is performed to predict the effect of EGR on the thermodynamic efficiency for various equivalence ratios. Experiments of a preheated air condensing boiler with EGR were conducted to measure the changes in the thermal efficiency and the characteristics of the pollutant emission. Finally, a 1-D premixed code was calculated to understand the effect of the EGR method on the NO reduction mechanism. The results of the thermodynamic analysis show that the thermodynamic efficiency is not changed because the temperature and the amount of the exhaust gas are unchanged, even though the EGR method is implemented in the system. However, when the EGR method is used with an equivalence ratio near 1.00, it is experimentally verified that the thermal efficiency increases and the NOx concentration decreases. Based on the results from numerical calculations, it is shown that the NO production rates of N + O2 ↔ NO + O and N + OH ↔ NO + H are remarkably changed due to the decrease in the flame temperature and the NO mole fraction is decreased. - Highlights: • Premixed combustion system with EGR is studied for a high efficiency and low NOx. • All research is performed with various EGR and equivalence ratios. • It verified that efficiency increases and the NOx emission decreases with EGR method. • NO production rates are remarkably changed by N + O2 ↔ NO + O and N + OH ↔ NO + H with EGR

  4. 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. PMID:26695777

  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. 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.

  7. Turbocharger efficiencies in pulsating exhaust gas flow; Turboladerwirkungsgrade in pulsierender Abgasstroemung

    Energy Technology Data Exchange (ETDEWEB)

    Aymanns, Richard; Scharf, Johannes; Uhlmann, Tolga [FEV GmbH, Aachen (Germany). Business Unit Gasoline Engines; Pischinger, Stefan [RWTH Aachen (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen

    2012-07-15

    The exhaust pressure pulse amplitudes in downsizing engines challenge the quasi steady modelling of turbocharger turbines in engine process simulation. An early selection of a well matching turbocharger is the key to time efficiency in the concept development phase of engines with ambitious performance and fuel economy targets. This article from FEV and RWTH Aachen assesses the turbocharger efficiencies in pulsating exhaust gas flow and gives a handling recommendation to minimise matching errors. (orig.)

  8. 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.

  9. High temperature gas reactor

    International Nuclear Information System (INIS)

    The present invention provides a reflector block structure of a high temperature gas reactor in which graphite blocks are not failed even a containing cylinder loaded to a fuel exchanger collides against to secured reflectors upon loading and withdrawing fuel constitutional elements. Namely, a protection plate made of a metal material such as stainless steel is covered on the secured reflector blocks disposed to the upper most step among secured graphite reflector blocks constituting the reactor core. In addition, positioning guide grooves are formed on the protection plate for guiding the containing cylinder loaded to the fuel exchanger to the column of the reactor core constitutional elements. With such a constitution, even if the containing cylinder of fuel exchanger is hoisted down and collided against the inner circumferential edge of the secured reflector blocks due to deviation of the position and the direction upon exchange of fuels, the reflector blocks are not failed since the above-mentioned portion is covered with the metal protection plate. In addition, the positioning guide grooves lead the fuel exchanger to a predetermined column correctly. (I.S.)

  10. Application of the water gas shift reaction to fusion fuel exhaust streams

    International Nuclear Information System (INIS)

    In a Fusion Fuel Clean Up (FCU) system, impurities will be removed from the fusion reactor exhaust and neutral beam line streams. Tritium in this impurity stream will be recovered and recycled to the fuel stream. In one flowsheet configuration of the Tritium Systems Test Assembly (TSTA), tritium is recovered from a simulated impurity stream via uranium hot metal beds and recycled to an isotope separation system. This study has shown, however, that the catalyzed water gas shift reaction, by which (H,D,T)2O and CO are converted to (H,D,T)2 and CO2 is a better method of (H,D,T)2O reduction than the hot metal beds. Catalytic reactors were designed, built and tested to provide data for the design of a prototype reactor to replace the hot metal beds in the FCU system. The prototype reactor contains only 10 g of catalyst and is expected to last at least 5 years. The reactor is small (1.3 cm OD x 13 cm long), operates at low temperatures (approximately 490 K) and will convert water to hydrogen, at a CO/H2O ratio of 1.5, with an efficiency of greater than 98 percent. Results show that the catalytic reactor is very stable even during upset conditions. Wide ranges of flow and a CO/H2O ratio variance from 1.3 upward have little effect on the conversion efficiency. Short term high temperature excursions do not affect the catalyst and lower temperatures will simply decrease the reaction rate resulting in lower conversions. The reactor appears to be unaffected by NO2, CO2, O2 and N2 in the feed stream at concentration levels expected in a fusion reactor exhaust stream

  11. Removal of Carbon Dioxide Gas From the Exhaust Gases Generated at the Takoradi Thermal Power Station

    Directory of Open Access Journals (Sweden)

    M. Charles

    2010-10-01

    Full Text Available Takoradi Thermal Power Station (TTPS generates electricity by burning fossil-fuel and hence it also generates greenhouse gases especially carbon dioxide, which is vented into the atmosphere. These greenhouse gases are pollutants known to cause global warming. A method for the removal of carbon dioxide gas from the exhaust gases generated at TTPS is proposed in this research. It aims at reducing the plant’s carbon dioxide emission into the atmosphere and hence reducing the plant’s rate of pollution into the atmosphere. The method employed is a modification of a method known as the Fluor Daniel ECONAMINE FG process. This method removes carbon dioxide from exhaust gas by using an amine solution which comes into “contact” with the exhaust gas in a counter-current manner. This method has been applied by 23 companies which produce CO2 on a large scale. However, before TTPS apply this method a cost feasibility study is recommended.

  12. Dynamic exhaust gas measurement with diode-lasers. Dynamische Abgasmessung mit Diodenlasern

    Energy Technology Data Exchange (ETDEWEB)

    Nitzschke, E.; Wolf, H.

    The future development of internal combustion engines requires an exact knowledge of dynamic processes. Information on the time resolved concentration of single exhaust gas components is of special importance. Measurement techniques should have a time resolution of one combustion cycle. The reported instrument fulfills this requirement and has a response time of 3 ms. The exhaust gas analysis is performed by using a spectroscopic technique with infrared diode lasers. First applications of the system have shown it to be important for the analysis and optimization of modern engines. With gas sampling close to the exhaust valve the combustion process can precisely be analyzed. Strong variations were observed between single combustion cycles. Sampling behind the catalyst high system speed revealed dynamic properties of the catalyst and motor management system. (orig./HW).

  13. 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.

  14. Exhaust Gas Emissions from a Rotating Detonation-wave Engine

    Science.gov (United States)

    Kailasanath, Kazhikathra; Schwer, Douglas

    2015-11-01

    Rotating detonation-wave engines (RDE) are a form of continuous detonation-wave engines. They potentially provide further gains in performance than an intermittent or pulsed detonation-wave engine (PDE). The overall flow field in an idealized RDE, primarily consisting of two concentric cylinders, has been discussed in previous meetings. Because of the high pressures involved and the lack of adequate reaction mechanisms for this regime, previous simulations have typically used simplified chemistry models. However, understanding the exhaust species concentrations in propulsion devices is important for both performance considerations as well as estimating pollutant emissions. Progress towards addressing this need will be discussed in this talk. In this approach, an induction parameter model is used for simulating the detonation but a more detailed finite-chemistry model including NOx chemistry is used in the expansion flow region, where the pressures are lower and the uncertainties in the chemistry model are greatly reduced. Results show that overall radical concentrations in the exhaust flow are substantially lower than from earlier predictions with simplified models. The performance of a baseline hydrogen/air RDE increased from 4940 s to 5000 s with the expansion flow chemistry, due to recombination of radicals and more production of H2O, resulting in additional heat release. Work sponsored by the Office of Naval Research.

  15. Feeding a Gas Turbine with Aluminum Plant Exhaust for Increased CO2 Concentration in Capture Plant

    OpenAIRE

    Jordal, Kristin; Anantharaman, Rahul; Genrup, Magnus; Aarhaug, Thor Anders; Bakken, Jørn; Lilliestråle, Astrid; Mejdell, Thor; Holt, Nancy J.

    2015-01-01

    Aluminum production contributes to global CO2 emissions both due to the production process itself and due to the generation of electric power required for aluminum production. A concept is presented for increasing the CO2 concentration in the aluminum exhaust from ∼1% to ∼5% through the feeding of aluminum plant exhaust gas to a natural gas combined cycle (NGCC). The specific energy demand for CO2 capture is therewith reduced for both the aluminum plant and the NGCC. An evaluation was made of...

  16. 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.

  17. NOVEL GAS SENSORS FOR HIGH-TEMPERATURE FOSSIL FUEL APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Palitha Jayaweera

    2004-05-01

    SRI is developing ceramic-based microsensors for detection of exhaust gases such as NO, NO{sub 2}, and CO in advanced combustion and gasification systems. The sensors detect the electrochemical activity of the exhaust gas species on catalytic electrodes and are designed to operate at high temperatures, elevated pressures, and corrosive environments typical of large power generation exhausts. Under this research project we are developing sensors for multiple gas detection in a single package along with data acquisition and control software and hardware. The sensor package can be easily integrated into online monitoring systems for active emission control. This report details the research activities performed from May 2004 to October 2004 including testing of catalytic materials, sensor design and fabrication, and software development.

  18. 40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas sampling system; Otto... Year New Light-Duty Vehicles and New Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles; Test Procedures § 86.109-94 Exhaust gas sampling system; Otto-cycle vehicles not requiring...

  19. 40 CFR 86.110-90 - Exhaust gas sampling system; diesel vehicles.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas sampling system; diesel vehicles. 86.110-90 Section 86.110-90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... connected to a dilution tunnel. Figure B90-5 is a schematic drawing of the PDP system. Figure B90-6 is...

  20. 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....

  1. 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...

  2. An overview of exhaust emissions regulatory requirements and control technology for stationary natural gas engines

    International Nuclear Information System (INIS)

    In this paper a practical overview of stationary natural gas engine exhaust emissions control technology and trends in emissions regulatory requirements is presented. Selective and non-selective catalytic reduction and lean burn technologies are compared. Particular emphasis is focussed on implications of the Clean Air Act of 1990. Recent emissions reduction conversion kit developments and a practical approach to continuous monitoring are discussed

  3. Research Progress About Gas-Exhaust-Device for Fuel Element

    Institute of Scientific and Technical Information of China (English)

    ZHONG; Wu-ye

    2012-01-01

    <正>UO2-x stack applied in the fuel element has a form of a cylinder with a central hole, where temperature field characterized by high temperature and high gradient is formed due to irradiation. Then nearly all of the gaseous fission products (GFPs) can release into central cavity. However, uranium oxide will evaporate form the fuel stack’s inner surface because of its high temperature (about 1 800-2 000 ℃),

  4. Interaction between Struts and Swirl Flow in Gas Turbine Exhaust Diffusers

    Institute of Scientific and Technical Information of China (English)

    Roman Z.PIETRASCH; Joerg R. SEUME

    2005-01-01

    The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modem gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions.Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter (LDV). Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle settings. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.

  5. Trigeneration scheme for energy efficiency enhancement in a natural gas processing plant through turbine exhaust gas waste heat utilization

    International Nuclear Information System (INIS)

    Highlights: ► Efficiency enhancement of Natural Gas (NG) processing plants in hot/humid climates. ► Gas turbine waste heat powered trigeneration scheme using absorption refrigeration. ► Annual NG savings of 1879 MSCM and operating cost savings of US$ 20.9 million realized. ► Trigeneration scheme payback period estimated at approximately 1 year. ► Significant economical and environmental benefits for NG processing plants. - Abstract: The performance of Natural Gas Processing Plants (NGPPs) can be enhanced with the integration of Combined Cooling, Heating and Power (CCHP) generation schemes. This paper analyzes the integration of a trigeneration scheme within a NGPP, that utilizes waste heat from gas turbine exhaust gases to generate process steam in a Waste Heat Recovery Steam Generator (WHRSG). Part of the steam generated is used to power double-effect water–lithium bromide (H2O–LiBr) absorption chillers that provide gas turbine compressor inlet air-cooling. Another portion of the steam is utilized to meet part furnace heating load, and supplement plant electrical power in a combined regenerative Rankine cycle. A detailed techno-economic analysis of scheme performance is presented based on thermodynamic predictions obtained using Engineering Equation Solver (EES). The results indicate that the trigeneration system could recover 79.7 MW of gas turbine waste heat, 37.1 MW of which could be utilized by three steam-fired H2O–LiBr absorption chillers to provide 45 MW of cooling at 5 °C. This could save approximately 9 MW of electric energy required by a typical compression chiller, while providing the same amount of cooling. In addition, the combined cycle generates 22.6 MW of additional electrical energy for the plant, while process heating reduces furnace oil consumption by 0.23 MSCM per annum. Overall, the trigeneration scheme would result in annual natural gas fuel savings of approximately 1879 MSCM, and annual operating cost savings of

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel

    International Nuclear Information System (INIS)

    A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N2 dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke emissions. figs.

  8. Analysis of Exhaust Gas Waste Heat Recovery and Pollution Processing for Z12V190 Diesel Engine

    Directory of Open Access Journals (Sweden)

    Hou Xuejun

    2012-06-01

    Full Text Available With the increasingly prominent problem regarding rapid economy development and the gradually serious environmental pollution, the waste heat recovery and waste gas pollution processing have received significant attention. Z12V190 diesel engine has high fuel consumption and low thermal efficiency and releases large amounts of exhaust gas and waste heat into the atmosphere, causing serious problems of energy waste and environmental pollution. In this work, the diesel engine exhaust gas components are analysed and the diesel engine exhaust emission rates and exhaust gas waste heat rates are calculated. The calculating results proved the economic feasibility of waste heat recovery from Z12V190 diesel engine exhaust gas. Then, the mainly harmful components are analysed and the corresponding methods of purification and processing about Z12V190 diesel engine exhaust gas pollution discussed. In order to achieve full recovery of waste heat, save energy, purify treatment pollution and ultimate to lay the foundation for waste gas recovery and pollution treatment, the comprehensive process flows of Z12V190 diesel engine exhaust gas pollution processing and waste heat recovery are preliminary designed.

  9. 40 CFR 86.509-90 - Exhaust gas sampling system.

    Science.gov (United States)

    2010-07-01

    ... cooling and resulting condensation in the sample lines), a critical flow venturi, and assorted valves, and... flow over the test period. (2) Vehicle tailpipe to CVS duct. For methanol fueled vehicles, cooling of... (insulation may remain in place and/or heating may occur during testing provided maximum temperature is...

  10. Study of modeling theory of multiphase gas distribution in exhaust process of automobile

    Institute of Scientific and Technical Information of China (English)

    臧杰

    2004-01-01

    According to experiments and the phenomena that tailpipes often have dirty particulate matter, this paper takes dynamic theory analysis as its study aim, beginning with the description method of multiphase gas distribution differential equation. According to the characteristics that exhaust gas will flow with high velocity in a tailpipe, it is supposed that gas mass that differ largely will layer when flowing with high velocity in a tailpipe.This means the exhaust gas is mixed with particulate matter, gas with large mass (CO2 ,HC,NOx ) and gas with small mass (CO,H2O,N2 ,O2). The interface of two phase fluid will be become clearer as it flows in the pipe for a long distance. The fluid continuous equation between gas phase and solid phase and the mathematical relationship between the geometry parameter and the flowing are established by a multiphase gas flowing theory. Analyzing the interface and state of layers will provide a basic theory for developing a catalytic converter with high efficiency.

  11. The effect of piston bowl temperature on diesel exhaust emissions

    OpenAIRE

    Ladommatos, N; Xiao, Z.; Zhao, H.

    2005-01-01

    In modern, high-speed, direct injection diesel engines for passenger vehicles, there is extensive impingement of the fuel sprays on to the piston bowl walls. Recent trends towards smaller engine sizes, equipped with high-pressure common-rail fuel injection systems, have tended to increase the spray/piston wall interaction. This paper describes tests carried out in a high-speed direct injection automotive diesel engine, during which the temperature of the piston was increased in a controlled m...

  12. Analysis of Exhaust Gas Waste Heat Recovery and Pollution Processing for Z12V190 Diesel Engine

    OpenAIRE

    Hou Xuejun; Gao Deli

    2012-01-01

    With the increasingly prominent problem regarding rapid economy development and the gradually serious environmental pollution, the waste heat recovery and waste gas pollution processing have received significant attention. Z12V190 diesel engine has high fuel consumption and low thermal efficiency and releases large amounts of exhaust gas and waste heat into the atmosphere, causing serious problems of energy waste and environmental pollution. In this work, the diesel engine exhaust gas compone...

  13. Experimental research on exhaust gas purifying facilities in incinerating treatment of radioactive wastes

    International Nuclear Information System (INIS)

    Among the research on the incinerating treatment of combustible low level wastes, three items, that is, combustible low level radioactive wastes and incinerating treatment method, wet type exhaust gas purifying facilities and ceramic filter type dry exhaust gas purifying facilities, were selected, and experimental research was carried out on the main theme of exhaust gas purification in the incineration of low level radioactive wastes. The definition of combustible low level radioactive wastes was decided, and the wastes conforming to this criteria were investigated and classified. The combustible low level wastes generated in the Tokai Research Establishment were classified and weighed, and the results reflected well the state of activities. The change of radioactive wastes to radioactive aerosol, radioactive gas and residue by incineration was investigated. The effect of volume reduction by incineration was studied. The decontamination performance of wet purifying system, the release of tritium steam, the cooling capacity of scrubbers and their corrosion, the construction of the test incinerator using ceramic filters, and the various tests on ceramic filters are reported. (K.I.)

  14. 4-Nitrophenol, 1-nitropyrene, and 9-nitroanthracene emissions in exhaust particles from diesel vehicles with different exhaust gas treatments

    Science.gov (United States)

    Inomata, Satoshi; Fushimi, Akihiro; Sato, Kei; Fujitani, Yuji; Yamada, Hiroyuki

    2015-06-01

    The dependence of nitro-organic compound emissions in automotive exhaust particles on the type of aftertreatment used was investigated. Three diesel vehicles with different aftertreatment systems (an oxidation catalyst, vehicle-DOC; a particulate matter and NOx reduction system, vehicle-DPNR; and a urea-based selective catalytic reduction system, vehicle-SCR) and a gasoline car with a three-way catalyst were tested. Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) and nitrophenols in the particles emitted were analyzed by thermal desorption gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. The secondary production of nitro-organic compounds on the filters used to collect particles and the adsorption of gaseous nitro-organic compounds by the filters were evaluated. Emissions of 1-nitropyrene, 9-nitroanthracene, and 4-nitrophenol in the diesel exhaust particles were then quantified. The NOx reduction process in vehicle-DPNR appeared to remove nitro-hydrocarbons efficiently but not to remove nitro-oxygenated hydrocarbons efficiently. The nitro-PAH emission factors were lower for vehicle-DOC when it was not fitted with a catalyst than when it was fitted with a catalyst. The 4-nitrophenol emission factors were also lower for vehicle-DOC with a catalyst than vehicle-DOC without a catalyst, suggesting that the oxidation catalyst was a source of both nitro-PAHs and 4-nitrophenol. The time-resolved aerosol mass spectrometry data suggested that nitro-organic compounds are mainly produced when an engine is working under load. The presence of 4-nitrophenol in the particles was not confirmed statistically because of interference from gaseous 4-nitrophenol. Systematic errors in the estimated amounts of gaseous 1-nitropyrene and 9-nitroanthracene adsorbed onto the filters and the estimated amounts of volatile nitro-organic compounds that evaporated during sampling and during post-sampling conditioning could not be excluded. An analytical method

  15. Optimization of a thermoelectric generator subsystem for high temperature PEM fuel cell exhaust heat recovery

    DEFF Research Database (Denmark)

    Gao, Xin; Andreasen, Søren Juhl; Kær, Søren Knudsen;

    2014-01-01

    In previous work, a thermoelectric (TE) exhaust heat recovery subsystem for a high temperature polymer electrolyte membrane (HT-PEM) fuel cell stack was developed and modeled. Numerical simulations were conducted and have identified an optimized subsystem configuration and 4 types of compact heat...... modules are now connected into branches. The procedures of designing and optimizing this TE exhaust heat recovery subsystem are drawn out. The contribution of TE exhaust heat recovery to the HT-PEM fuel cell power system is preliminarily concluded. Its feasibility is also discussed....... cell stack. All through this study, different electrical connection styles of all the thermoelectric generator (TEG) modules in the subsystem and their influences are also discussed. In the end, the subsystem configuration is further optimized and a higher subsystem power output is achieved. All TEG...

  16. 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

    recirculation. The paper provides proof of exponential stabilityfor closed loop control of the model given. Difficulties in the system include that certaindisturbance levels will make a desired setpoint in O2 unreachable, for reasons of the physics of thesystem, and it is proven that the proposed control......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....

  17. 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

  18. 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

    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...... principles followed by parameter identication and compares the results of these approaches. The paper performs a validation against experimental data from a test engine and presents a linearised model for EGR control design....

  19. Evaluation of Exhaust Gas Condensing Economizer Installation at Riga CHP Plants

    OpenAIRE

    Zigurs, Aris; Kunickis, Maris; Balodis, Maris; Linkevics, Olegs; Stuklis, Ilmars; Ivanova, Polina

    2015-01-01

    In this study, passive exhaust gas condensing economizer installation is evaluated at Riga CHP plants No. 1 and No. 2 to increase efficiency of heat only boilers (HOBs). Five options are investigated: two options for Riga CHP plant No. 1 and three options for Riga CHP plant No. 2. The study provides the analysis of HOBs operation statistics, determination of HOBs operation trends, development of production programmes, as well as economic and sensitivity analysis of the considered options. Bas...

  20. Investigation of Materials for Use in Exhaust Gas Condensate Environment with Focus on EGR systems

    OpenAIRE

    Olofsson, Andreas

    2012-01-01

    EGR (Exhaust Gas Recirculation) ar en teknik som anvands for dieselmotorer, for att mota de hart satta utslappskraven for kvaveoxider. EGR fungerar genom att en del av avgaserna aterfors till cylindrarna. Avgaserna gor sa att den maximala forbranningstemperaturen sanks, vilket kraftigt reducerar bildandet av kvaveoxider. Dieselavgaser inneh aller framst CO2, NOx, SO2 och H2O och innan avgasernaaterfors till cylindrarna kyls de ner. Detta leder till att det bildas ett korrosivt kondensat, eft...

  1. Analysis of impulse electric field effect on organic exhaust gas decomposition

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The technique of organic exhaust gas decomposition with impulse corono-dischrge plasma has been investigated in this study. It has been discovered that the impulse electric fieldaffected the decomposition efficiency with the secondary electron emission coefficient (δ of the corona electrode as an intermediate: when W was fixed the corona electrode material with higher δcould induce higher decomposition efficiency. In these experiments,wolfram electrode which has the highest δhas really induced the highest decomposition efficiency.

  2. 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...... plate-fin heat exchangers is adopted. Then the model is validated against experimental data and the main variables are identified by means of a sensitivity analysis. Finally, the system configuration is optimized for recovering heat from the exhaust gas. The results exhibit the crucial importance...... of the model accuracy and the optimization on system configuration. Future studies will concentrate on heat exchanger structures....

  3. 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

    2016-02-23

    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.

  4. 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

  5. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas sampling system; Diesel... of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF... the outside surface of the CVS duct or dilution tunnel....

  6. Enhanced Performance of Discharge Plasma in Raw Engine Exhaust Treatment-Operation under Different Temperatures and Loads

    Institute of Scientific and Technical Information of China (English)

    B S Rajanikanth; A D Srinivasan; Subhankar das

    2005-01-01

    This paper reports improved performance of discharge plasma in raw engine exhaust treatment. For the purpose of investigation, both filtered and raw diesel engine exhaust were separately treated by the discharge plasma. In raw exhaust environment, the discharge plasma exhibits a superior performance with regard to NOx removal, energy consumption and formation of by-products. In this study, experiments were conducted at conditions of different temperatures and loads.

  7. Effects of injection pressure and injection timing to exhaust gas opacity for a conventional indirect diesel engine

    Science.gov (United States)

    Budiman, Agus; Majid, Akmal Irfan; Pambayun, Nirmala Adhi Yoga; Yuswono, Lilik Chaerul; Sukoco

    2016-06-01

    In relation to pollution control and environmental friendliness, the quality of exhaust gas from diesel engine needs to be considered. The influences of injection pressure and timing to exhaust gas opacity were investigated. A series of experiments were conducted in a one-cylinder conventional diesel engine with a naturally aspirated system and indirect injection. The default specification of injection pressure was 120 kg/cm2. To investigate the injection pressure, the engine speed was retained on 1000 rpm with pressure variations from 80 to 215 kg/cm2. On the other hand, the various injection timing (8, 10, 12, 16 degrees before TDC point and exact 18 degrees before TDC point) were used to determine their effects to exhaust gas opacity. In this case, the engine speed was varied from 1000 to 2400 rpm. The injector tester was used to measure injection pressure whereas the exhaust gas opacity was determined by the smoke meter. Those data were also statistically analyzed by product moment correlation. As the results, the injection pressure of diesel engine had a non-significant positive correlation to the exhaust gas opacity with r = 0.113 and p > 5 %. Injection pressure should be adjusted to the specification listed on the diesel engine as if it was too high or too low will lead to the higher opacity. Moreover, there was a significant positive correlation between injection timing and the exhaust gas opacity in all engine speeds.

  8. 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

  9. 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 NO(x) 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 NO(x)-loading of lean NO(x) traps, and the soot loading of Diesel particulate filters. PMID:22163575

  10. 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)

  11. Multiple Exhaust Nozzle Effects on J-2X Gas Generator Outlet Impedance

    Science.gov (United States)

    Kenny, R. Jeremy; Muss, Jeffrey; Hulka, James R.; Casiano, Matthew

    2010-01-01

    The current test setup of the J-2X gas generator system uses a multiple nozzle configuration to exhaust hot gases to drive the propellant supply turbines. Combustion stability assessment of this gas generator design requires knowledge of the impedance effects the multiple nozzle configuration creates on the combustion chamber acoustic modes. Parallel work between NASA and Sierra Engineering is presented, showing two methods used to calculate the effective end impedance resulting from multiple nozzle configurations. The NASA method is a simple estimate of the effective impedance using the long wavelength approximation. Sierra Engineering has developed a more robust numerical integration method implemented in ROCCID to accommodate for multiple nozzles. Analysis using both methods are compared to J-2X gas generator test data collected over the past year.

  12. 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.

  13. Ion beam analyses of particulate matter in exhaust gas of a ship diesel engine

    Science.gov (United States)

    Furuyama, Yuichi; Fujita, Hirotsugu; Taniike, Akira; Kitamura, Akira

    2011-12-01

    There is an urgent need to reduce emission of the particulate matter (PM) in the exhaust gas from ship diesel engines causing various health hazards and serious environmental pollution. Usually the heavy fuel oil (HFO) for ships is of low quality, and contains various kinds of impurities. Therefore, the emission of PM along with exhaust gas from ship diesel engines is one of the most serious environmental issues. However, the PM fundamental properties are not well known. Therefore, it is important to perform elemental analysis of the PM. The HFO contains sulfur with a relatively high concentration of a few percent. It is important to make quantitative measurements of sulfur in the PM, because this element is poisonous for the human body. In the present work, PM samples were collected from exhaust gas of a test engine, and RBS and PIXE analyses were applied successfully to quantitative analysis of the PM samples. The RBS analysis enabled quantitative analysis of sulfur and carbon in the collected PM, while heavier elements such as vanadium and iron were analyzed quantitatively with the PIXE analysis. It has been found that the concentration ratio of sulfur to carbon was between 0.007 and 0.012, and did not strongly depend on the output power of the engine. The S/ C ratio is approximately equal to the original composition of the HFO used in the present work, 0.01. From the known conversion ratio 0.015 of sulfur in the HFO to sulfates, the conversion ratio of carbon in the HFO to the PM is found to be 0.01-0.02 by the RBS measurements. On the other hand, the PIXE analysis revealed a vanadium enrichment of one order of magnitude in the PM.

  14. Evaluation of an exhaust gas evacuation system during propane-fueled lift truck maintenance

    International Nuclear Information System (INIS)

    Exposure to carbon monoxide (CO) gas in the workplace can cause health problem. CO gas is colourless and odourless, and exposure to it can cause intoxication, particularly for mechanics working on internal combustion engines fed by propane-fueled lift trucks. Regular procedures for evacuating the gases emitted during routine mechanical repairs involve the use of rigid evacuating pipes attached to the building and hooked to a flexible pipe at the end of the exhaust pipe. With lift trucks, this procedure is limited because of the configuration of these vehicles, and also because this type of work is often done in places without access to permanent mechanical ventilation. The object of this study was to propose a new evacuation method for CO gas fumes that would lower the exposures of fumes for mechanics and for workstations. It identified the criteria that should be considered, such as the configuration of the existing exhaust system of lift trucks, and feasibility of using this system at a variety of on-site locations. The design of the device was described and evaluated. 7 refs., 6 tabs., 8 figs., 3 appendices

  15. 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.

  16. 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.

  17. 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.

  18. 对废气中氮化物的测量%Measurement of nitrogen compounds in exhaust gas

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Environmental standards and technological advances continue to cut emission levels. The lowering of pollutant concentrations in exhaust gas is increasing demands on measurement technology. Measurement of pollutants is required for monitoring and adjusting pollutant reduction systems. Such measurement equipment must be reliable and low maintenance. Continuous gas analyzers from ABB show how innovative approaches permit industrial metrology to achieve higher sensitivity.

  19. 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

    2012-08-01

    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. PMID:22732009

  20. 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

    2012-08-01

    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.

  1. KATsim. A tool for numerically simulating exhaust-gas catalysts; KATsim. Ein Werkzeug zur numerischen Simulation von Abgaskatalysatoren

    Energy Technology Data Exchange (ETDEWEB)

    Dusemund, Sandra; Schneider, Hellfried; Langeheinecke, Kay [IAV GmbH, Gifhorn (Germany). Geschaeftsbereich Powertrain Mechatronik; Bank, Robert [Rostock Univ. (Germany). Lehrstuhl fuer Technische Thermodynamik

    2009-11-15

    The demands placed on numerically simulating exhaust-gas aftertreatment components are manifold. In addition to laying out the process engineering of exhaust-emission systems, the focus also rests on concept studies for their configuration as well as on 3-D simulations. Increasingly, simulations are also being used for developing and calibrating algorithms for engine control units. To meet these different requirements, IAV is developing the KATsim modular numeric simulation system. (orig.)

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

    International Nuclear Information System (INIS)

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

  3. Analysis of a Temperature-Controlled Exhaust Thermoelectric Generator During a Driving Cycle

    Science.gov (United States)

    Brito, F. P.; Alves, A.; Pires, J. M.; Martins, L. B.; Martins, J.; Oliveira, J.; Teixeira, J.; Goncalves, L. M.; Hall, M. J.

    2016-03-01

    Thermoelectric generators can be used in automotive exhaust energy recovery. As car engines operate under wide variable loads, it is a challenge to design a system for operating efficiently under these variable conditions. This means being able to avoid excessive thermal dilution under low engine loads and being able to operate under high load, high temperature events without the need to deflect the exhaust gases with bypass systems. The authors have previously proposed a thermoelectric generator (TEG) concept with temperature control based on the operating principle of the variable conductance heat pipe/thermosiphon. This strategy allows the TEG modules’ hot face to work under constant, optimized temperature. The variable engine load will only affect the number of modules exposed to the heat source, not the heat transfer temperature. This prevents module overheating under high engine loads and avoids thermal dilution under low engine loads. The present work assesses the merit of the aforementioned approach by analysing the generator output during driving cycles simulated with an energy model of a light vehicle. For the baseline evaporator and condenser configuration, the driving cycle averaged electrical power outputs were approximately 320 W and 550 W for the type-approval Worldwide harmonized light vehicles test procedure Class 3 driving cycle and for a real-world highway driving cycle, respectively.

  4. Application of Ceria and Lanthana in Catalyst for Cleansing Exhaust Gas of Car

    Institute of Scientific and Technical Information of China (English)

    Yang Chunsheng; Chen Jianhua; Dai Shaojun

    2004-01-01

    The importanCe of rare earths being applied in the catalyst for cleansing the exhaust gas out of car was introduced. The acting mechanism of ceria and lanthana in catalyst and its influencing factors were discussed, and its prospect was forecasted. Pt-Rh precious metals three-way catalyst is widely used for decontaminating the exhaust gas of car now. Ceria and lanthana, which can decrease the content of Pt-Rh and increase the content of Pd in the catalyst, are used as additive in the decontaminating catalyst in order to solve the problem of the supply and demand of Pt and Rh.It is reported that increasing the activity of the coat on catalyst, regulating automatically the ratio of air and fuel, acting as catalyst-accelerator, and improving its properties such as thermal stability and strength may primarily amount for the catalyzing, mechanism of ceria and lanthana. The factors, such as their interaction, additive methods, and effects of cocatalyst ZrO2, CuO, AgO, etc. , will remarkably influence the catalyzing function of ceria and lanthana.

  5. Oxidation and exhaust gas corrosion resistance of the cobalt base clad layers

    Directory of Open Access Journals (Sweden)

    H. Smolenska

    2008-12-01

    Full Text Available Purpose: Purpose of this work is describing the behaviour of the cobalt base cladding layers after treatment in hot air (750°C, 200 hours and exhaust gases (700°C, two month.Design/methodology/approach: The layers were produced by two cladding, laser and PTA, cladding technique. Cladding was conducted with a high power diode laser HDPL ROFIN SINAR DL 020 and Plasma Transformed Arc method. The layers consisted of three multitracking sublayers. The cobalt base layers were evaluated by microstructure investigations (optical and scanning electron microscope SEM, chemical analysis and micro hardness measurements.Findings: The microstructure of the investigated layers did not change much, neither on the top part nor in the clad/steel interface after treatment in both environments. On the outer surfaces the oxide layers were observed which consisted generally of chromium and iron oxides. The compositions of this scales were reviled by the EDS analyze. The changes in chemical compositions before and after oxidation and after corrosion in exhaust gases in the dendritic regions and micro regions were confirmed by the semi-quantitative chemical analysis (EDS. Neither the oxidation nor exposition for two month in exhaust gases did not influence on the morphology of the clad layers in any region however changes in chemical composition were observed. For both sort of clads the oxide layers were observed on the surface. The proposed layers are resistant for the hot exhausted gases.Research limitations/implications: The future researches should be done on microstructural and kinetic analyze of high temperature corrosion for higher temperature and times of the process.Practical implications: The clad layers, of this composition, were designed as a method to prolong service time for the ship engine exhausted valve and after this investigation the first valve heads with laser clad layer were installed in working ship engine.Originality/value: The chemical

  6. Novel Gas Sensors for High-Temperature Fossil Fuel Applications

    Energy Technology Data Exchange (ETDEWEB)

    Palitha Jayaweera; Francis Tanzella

    2005-03-01

    SRI International (SRI) is developing ceramic-based microsensors to detect exhaust gases such as NO, NO{sub 2}, and CO in advanced combustion and gasification systems under this DOE NETL-sponsored research project. The sensors detect the electrochemical activity of the exhaust gas species on catalytic electrodes attached to a solid state electrolyte and are designed to operate at the high temperatures, elevated pressures, and corrosive environments typical of large power generation exhausts. The sensors can be easily integrated into online monitoring systems for active emission control. The ultimate objective is to develop sensors for multiple gas detection in a single package, along with data acquisition and control software and hardware, so that the information can be used for closed-loop control in novel advanced power generation systems. This report details the Phase I Proof-of-Concept, research activities performed from October 2003 to March 2005. SRI's research work includes synthesis of catalytic materials, sensor design and fabrication, software development, and demonstration of pulse voltammetric analysis of NO, NO{sub 2}, and CO gases on catalytic electrodes.

  7. Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas

    International Nuclear Information System (INIS)

    Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines, i.e. they use conventional Diesel fuel and a gaseous fuel as well. This technology is currently reintroduced, associated with efforts to overcome various difficulties of HCCI engines, using various fuels. The use of natural gas as an alternative fuel is a promising solution. The potential benefits of using natural gas in Diesel engines are both economical and environmental. The high autoignition temperature of natural gas is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under dual fuel conditions. The primary amount of fuel is the gaseous one, which is ignited by a pilot Diesel liquid injection. Comparative results are given for various engine speeds and loads for conventional Diesel and dual fuel operation, revealing the effect of dual fuel combustion on engine performance and exhaust emissions

  8. Exhaust circulation into dry gas desulfurization process to prevent carbon deposition in an Oxy-fuel IGCC power generation

    International Nuclear Information System (INIS)

    Highlights: • Power plant with semi-closed gas turbine and O2–CO2 coal gasifier was studied. • We adopt dry gas sulfur removal process to establish the system. • The exhaust gas circulation remarkably prevented carbon deposition. • Efficiency loss for exhaust gas circulation is quite small. • Appropriate operating condition of sulfur removal process is revealed. - Abstract: Semi-closed cycle operation of gas turbine fueled by oxygen–CO2 blown coal gasification provides efficient power generation with CO2 separation feature by excluding pre-combustion type CO2 capture that usually brings large efficiency loss. The plant efficiency at transmission end is estimated as 44% at lower heating value (LHV) providing compressed CO2 with concentration of 93 vol%. This power generation system will solve the contradiction between economical resource utilization and reduction of CO2 emission from coal-fired power plant. The system requires appropriate sulfur reduction process to protect gas turbine from corrosion and environment from sulfur emission. We adopt dry gas sulfur removal process to establish the system where apprehension about the detrimental carbon deposition from coal gas. The effect of circulation of a portion of exhaust gas to the process on the retardation of carbon deposition was examined at various gas compositions. The circulation remarkably prevented carbon deposition in the sulfur removal sorbent. The impact of the circulation on the thermal efficiency is smaller than the other auxiliary power consumption. Thus, the circulation is appropriate operation for the power generation

  9. Exhaust gas analysis and formation mechanism of SiC nanowires synthesized by thermal evaporation method

    Directory of Open Access Journals (Sweden)

    Noppasint Jiraborvornpongsa

    2014-09-01

    Full Text Available Silicon carbide nanowires (SiCNWs are a set of promising reinforcement materials due to their superior properties. However, formation mechanism of the SiCNWs synthesized by the thermal evaporation method without metal catalyst is still unclear. To understand the formation mechanism, SiCNWs were synthesized by the thermal evaporation method at 1350 °C using a pre-oxidized Si powder and CH4 gas as precursors. SiCNWs obtained by this method were β-SiC/SiO2 core–shell nanowires with average diameter about 55 nm and with a length up to 1 mm. The exhaust gases during the SiCNWs synthesis process were examined by gas chromatography and the photographs of growth activity of SiCNWs inside the furnace were captured. CO gas was detected during the active formation of SiCNWs. It was clarified that CO gas was one of the byproducts from SiCNWs synthesis process, and the formation reaction of SiCNWs should be 3SiO(g + 3C(s → 2SiC(s + SiO2(s + CO(g. The formation of SiCNWs was discussed based on the oxide-assisted-growth mechanism.

  10. Effect of the Sequence of the Thermoelectric Generator and the Three-Way Catalytic Converter on Exhaust Gas Conversion Efficiency

    Science.gov (United States)

    Su, Chuqi; Tong, Naiqiang; Xu, Yuman; Chen, Shan; Liu, Xun

    2013-07-01

    The potential for thermoelectric exhaust heat recovery in vehicles has increased with recent improvements in the efficiency of thermoelectric generators (TEGs). The problem with using thermoelectric generators for vehicle applications is whether the device is compatible with the original vehicle exhaust system, which determines the quality of the exhaust gas treatment and the realization of energy conservation and emission reduction. Based on ANSYS CFX simulation analysis of the impact of two positional relationships between the TEG and three-way catalytic converter in the exhaust system on the working efficiency of both elements, it is concluded that the layout with the front three-way catalytic converter has an advantage over the other layout mode under current conditions. New ideas for an improvement program are proposed to provide the basis for further research.

  11. 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)

  12. A study on exhaust gas emissions from ships in Turkish Straits

    International Nuclear Information System (INIS)

    The Turkish Straits, i.e. Istanbul (Bosphorus) and Canakkale (Dardanellen), which connect Black Sea and Aegean Sea, have a continuously increasing maritime traffic. Especially, the maritime traffic on Bosphorus (Istanbul Strait) that connects the continents of Europe and Asia is too complex due to geographical conditions. The maritime traffic in the Turkish Straits includes the ships, which are in use in domestic transport, the transit passing ships with various aims and fishing, sport or strolling ships. In this paper, fuel consumption and exhaust gas emissions NOx, CO, CO2, VOC, PM exhausted from ships such as transit vessels, which are passing both Bosphorus and Dardanellen, and passenger ships used in domestic transport on the Bosphorus are calculated. In order to do this the general characteristics, the main engine systems, the fuel types, cruising times and speeds of all vessels are taken into consideration. The calculated NOx emissions on the Bosphorus are 2720t from domestic passenger ships and 4357t from transit ships. In this case it is clear that the transit ships cause more than half of the total amount of emissions from ships on the Bosphorus. The amount of nitrogen oxide emissions from domestic passenger ships used for public transport in Istanbul Strait is equal to approx. 4% of nitrogen oxide emissions from motor vehicles in Istanbul. Finally, the future emissions from ships in Turkish Straits are discussed. (Author)

  13. Control of gaseous pollutants emission with EGR (exhaust gas recirculation) and catalytic converter

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Fernando Silva de Araujo [Faculdade de Engenharia Quimica de Lorena (FAENQUIL), SP (Brazil); Mann, Jens; Ueberschaer, Dietmar [Fachhochschule Darmstadt (Germany). Fachbereich Maschinenbau; Balestieri, Jose Antonio Perrella; Nascimento, Nazem [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia]. E-mail: ftilor@eu.ansp.br; perrella@feg.unesp.br; nazem@feg.unesp.br

    1997-07-01

    Study of gaseous pollutant emission from engine tests simulating real work conditions, using spark point manually controlled and exhaust gas recirculation in diverse proportion levels. The objective of this present work is to re-examine the potential of the EGR conception, a well-known method of combustion control, employed together electronic fuel injection and three-way catalytic converter closed-loop control at a spark ignition engine, verifying the performance characteristics and technical availability of this conception to improve pollution control and fuel economy. The pollutant emissions under operational conditions were analyzed and compared with the expected by concerning theory and real tests performed by EGR equipped engines by factory. (author)

  14. EFFECTS OF COOLED EXTERNAL EXHAUST GAS RECIRCULATION ON DIESEL HOMOGENEOUS CHARGE COMPRESSION IGNITION ENGINE

    Institute of Scientific and Technical Information of China (English)

    SHI Lei; CUI Yi; DENG Kangyao

    2007-01-01

    The effects of cooled external exhaust gas recirculation (EGR) on the combustion and emission performance of diesel fuel homogeneous charge compression ignition (HCCI) are studied. Homogeneous mixture is formed by injecting fuel in-cylinder in the negative valve overlap (NVO) period. So, the HCCI combustion which has low NOx and smoke emission is achieved. Cooled external EGR can delay the start of combustion effectively, which is very useful for high cetane fuel (diesel) HCCI, because these fuels can easily self-ignition, which makes the start of combustion more early. External EGR can avoid the knock combustion of HCCI at high load which means that the EGR can expand the high load limit. HCCI maintains low smoke emission at various EGR rate and various load compared with conventional diesel engine because there is no fuel-rich area in cylinder.

  15. Application of Irradiation. Application to polymer processing, exhaust gas treatment, sterilization of medical instruments and food

    International Nuclear Information System (INIS)

    Many fields such as industry, agriculture, medical treatment and environment use radiation. This report explained some examples of irradiation applications. Radiation source is 60Co γ-ray. Polymer industry use radiation for radiation curing (thermally stable polymer), tire, expanded polymer, radiation induced graft copolymerization and electron beam curing. On environmental conservation, radiation is used for elimination of NOx and SOx in exhaust combustion gas. In the medical treatment, radiation is applied to sterilization of medical instruments, that occupied about 50% volume, and blood for transfusion, which is only one method to prevent GVHD after transfusion. On agriculture, irradiation to spice, dry vegetable, frozen kitchen, potato and garlic are carried out in 30 countries. However, potato is only a kind food in Japan. Radiation breeding and pest control are put in practice. (S.Y.)

  16. Dynamic instabilities in spark-ignited combustion engines with high exhaust gas recirculation

    Science.gov (United States)

    Daw, C. Stuart; Finney, Charles E. A.

    2011-04-01

    We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR.

  17. Dual-catalyst aftertreatment of lean-burn natural gas engine exhaust

    International Nuclear Information System (INIS)

    A dual-catalyst system for the reduction of NO with CH4 under lean conditions was investigated. The system is comprised of a mixed bed containing a Co/ZrO2 catalyst, active for the oxidation of NO to NO2, and a Pd/sulfated zirconia (SZ) catalyst that is active for the reduction of NO2 with CH4. Such a system is capable of taking advantage of higher reduction rates for NO2, as compared to NO, that have been previously observed. When simulated exhaust streams from lean-burn natural gas engines are used as feed, the dual-catalyst system is simultaneously active for the reduction of NOx and the oxidation of unburned hydrocarbons and CO. (author)

  18. Effects of exhaust gas recirculation on the thermal efficiency and combustion characteristics for premixed combustion system

    International Nuclear Information System (INIS)

    In this research, a boiler in a premixed combustion system used to achieve exhaust gas recirculation was investigated as a way to achieve high thermal efficiencies and low pollutant emissions. The effects of various exhaust gas recirculation (EGR) ratios, equivalence ratios and boiler capacities on thermal efficiency, NOx and CO emissions and the flame behavior on the burner surface were examined both experimentally and numerically. The results of the experiments showed that when EGR was used, the NOx and CO concentrations decreased and the thermal efficiency increased. In the case of a 15% EGR ratio at an equivalence ratio of 0.90, NOx concentrations were found to be smaller than for the current operating condition of the boiler, and the thermal efficiency was approximately 4.7% higher. However, unlike NOx concentrations, although the EGR ratio was increased to 20% at an equivalence ratio of 0.90, the CO concentration was higher than in the current operating condition of the boiler. From the viewpoint of burner safety, the red glow on the burner surface was noticeably reduced when EGR was used. These results confirmed that the EGR method is advantageous from the standpoint of reducing emission concentrations and ensuring burner safety. -- Highlights: ► The premixed boiler system applied EGR was investigated to achieve high thermal efficiencies and low pollutant emissions. ► Thermal efficiency and emission characteristics were examined with EGR ratios, equivalence ratios and boiler capacities. ► EGR method is advantageous from the standpoint of reducing emission concentrations and ensuring burner safety.

  19. Purification of exhaust gas from stenter%定形机废气的净化处理

    Institute of Scientific and Technical Information of China (English)

    黄晨昀

    2013-01-01

    定形机废气含有大量挥发性有机化合物,若不处理,会危害人体健康,影响生态环境.对此,可采用定形机废气净化处理技术,包括定形机废气的降温,蜂巢式高压工业静电除油烟,喷淋式除油烟以及废气除臭技术等.%The exhaust gas from heat setting machine contains large amounts of volatile organic compounds(VOCs) , it will endanger human health and ecological environment if not been processed. Purification technologies of exhaust gas from stenter are introduced, including cooling, removing fumes with high pressure static electricity generated by honeycombed device or spray system, as well as exhaust deodorization technology.

  20. The Effect of Ambient Temperature and Exercise to the Level of Exhaustion on

    Directory of Open Access Journals (Sweden)

    Somaye Kasharafifard

    2014-06-01

    Full Text Available Background: The increase in the amount of heat shock protein and C-reactive protein occurring as a result of stress was done with the aims of returning cell homeostasis, successful restoration of cell injury and protection of cell against more injuries. Materials and Methods: Fifteen climber and 15 non athlete subjects were chosen. A selected aerobic test was done by the subjects using Monark bicycle under two different conditions. Before starting the test, the subjects were exposed to a normal condition with the temperature of 24±2°C for an hour and a blood sample was taken from all the subjects. Then immediately, the subjects took the selected aerobic test to the level of exhaustion and blood sample was taken again. A week later, these subjects were exposed to a heated environment with the temperature of 38±2°C, followed by blood sample taking. Finally, the test was done by the subjects to the level of exhaustion and the last blood sample was taken. Then, the amount of heat shock protein (HSP and C - reactive protein (CRP in blood samples was measured. Results: A meaningful difference was observed in the changes of heat shock proteins (p=0.012 and C-reactive protein (p=0.02 between athlete and non athlete subjects. There was no meaningful difference in CRP and HSP in normal and hot condition for non athlete subjects before and after the test. But the result of the study demonstrates that There was a meaningful difference for athletes in both conditions before and after the test (p=0.002. Conclusion: Based on the study, it is claimed that while an athlete is exposed to several stressful conditions (e.g. high temperature and physical exercise, compared to a non athlete, the reaction of his body cells is more significant in order to prevent the injury.

  1. NO{sub x} reduction from a heavy-duty diesel engine with direct injection of natural gas and cooled exhaust gas recirculation

    Energy Technology Data Exchange (ETDEWEB)

    McTaggart-Cowan, G.; Bushe, W.K.; Hill, P.G. [British Columbia Univ., Dept. of Mechanical Engineering, Vancouver, BC (Canada); Munshi, S.R. [Westport Innovations Inc., Vancouver, BC (Canada)

    2004-06-01

    A heavy-duty ISX diesel engine has been commissioned for single-cylinder operation fuelled with pilot diesel ignited natural gas injected directly into the cylinder. The stock ISX engine was modified by replacing the diesel fuelling system with a high-pressure natural gas system, replacing the turbocharger with an independently controlled supercharger and installing a variable-flow exhaust gas recirculation (EGR) system. A study of the impact of cooled EGR on engine performance and gaseous emissions was carried out. Various engine speeds, loads and injection timings were tested over a range of EGR fractions. A preliminary study of the effect of EGR 'type' - supplemental or replacement - was also carried out. The results indicate that the NO{sub x} emissions varied linearly with the intake oxygen mass fraction (representative of the EGR fraction) until NO{sub x} emissions reached 20 per cent of their non-EGR levels. Further NO{sub x} reductions were achieved with higher EGR fractions, but the rate of reduction was significantly reduced. The NO{sub x} reductions were found to be independent of engine speed and load. An overall activation energy for NO{sub x} formation was determined by correlating the NO{sub x} reductions with a representative flame temperature. The emissions of combustion by-products, including carbon monoxide (CO)and unburned total hydrocarbons (THC) increased significantly at higher EGR fractions. The engine performance and efficiency were not significantly affected except at very high EGR fractions. (Author)

  2. Calculations of economy of 18-cylinder radial aircraft engine with exhaust-gas turbine geared to the crankshaft

    Science.gov (United States)

    Hannum, Richard W; Zimmerman, Richard H

    1945-01-01

    Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work.

  3. Low-temperature gas from marine shales

    OpenAIRE

    Jarvie Daniel M; Mango Frank D

    2009-01-01

    Abstract Thermal cracking of kerogens and bitumens is widely accepted as the major source of natural gas (thermal gas). Decomposition is believed to occur at high temperatures, between 100 and 200°C in the subsurface and generally above 300°C in the laboratory. Although there are examples of gas deposits possibly generated at lower temperatures, and reports of gas generation over long periods of time at 100°C, robust gas generation below 100°C under ordinary laboratory conditions is unprecede...

  4. The purification of internal combustion engine exhaust emissions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.J.; Jorgensen, Norman; Carlow, J.S.; Raybone, David.

    1994-03-02

    In this patent, improved catalytic reduction of exhaust gas pollutants from internal combustion engines is described. During the warm-up phase of the cycle, a plasma discharge is initiated in the exhaust gases upstream of the catalytic converter. The plasma is controlled using sensors which detect the catalyst temperature and gas pressure and flow rate. (UK)

  5. 热处理废气治理及环保标准%Handling of Exhaust Gas Originating from Heat Treatment and Related Environmental Standards

    Institute of Scientific and Technical Information of China (English)

    夏永辉; 苏兴武; 沈合利; 王红伟; 张峦

    2015-01-01

    The main source of exhaust gas in heat treatment trade and the standards related to exhaust gas discharging were introduced.The ways of handling exhaust gas were put forward.The exhaust gas originating from heat treatment should be strictly handled according to the relevant environmental standard,rendering discharged exhaust gas up to the standard.%介绍了热处理行业废气的主要来源及废气排放的相关标准,提出了治理废气的方法。热处理废气应该严格按相关的环保标准进行处理,使废气排放达标。

  6. PERFORMANCE AND EXHAUST GAS EMISSIONS ANALYSIS OF DIRECT INJECTION CNG-DIESEL DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    RANBIR SINGH

    2012-03-01

    Full Text Available Existing diesel engines are under stringent emission regulation particularly of smoke and particulate matter in their exhaust. Compressed Natural Gas and Diesel dual fuel operation is regarded as one of the best ways to control emissions from diesel engines and simultaneously saving petroleum based diesel fuel. Dual fuel engineis a conventional diesel engine which burn either gaseous fuel or diesel or both at the same time. In the present paper an experimental research was carried out on a laboratory single cylinder, four-stroke variable compression ratio, direct injection diesel engine converted to CNG-Diesel dual fuel mode to analyze the performance and emission characteristics of pure diesel first and then CNG-Diesel dual fuel mode. The measurements were recorded for the compression ratio of 15 and 17.5 at CNG substitution rates of 30% and 60% and varying theload from idle to rated load of 3.5kW in steps of 1 up to 3kW and then to 3.5kW. The results reveal that brake thermal efficiency of dual fuel engine is in the range of 30%-40% at the rated load of 3.5 kW which is 11%-13% higher than pure diesel engine for 30% and 60% CNG substitution rates. This trend is observed irrespective of the compression ratio of the engine. Brake specific fuel consumption of dual fuel engine is found better than pure diesel engine at all engine loads and for both CNG substitution rates. It is found that there is drastic reduction in CO, CO2, HC, NOx and smoke emissions in the exhaust of dual fuel engine at all loads and for 30% and 60% CNG substitution rates by employing some optimum operating conditions set forth for experimental investigations in this study.

  7. Pd catalysts supported on modified Zr0.5Al0.5O1.75 used for lean-burn natural gas vehicles exhaust purification

    Institute of Scientific and Technical Information of China (English)

    Hongyan Shang; Yun Wang; Maochu Gong; Yaoqiang Chen

    2012-01-01

    Composite supports Zr0.5Al0.5O1.75 modified by metal oxides,such as La2O3,ZnO,Y2O3 or BaO,were prepared by co-precipitation method,and palladium catalysts supported on the modified composite supports were prepared by impregnation method.Their properties were characterized by X-ray diffraction (XRD),NH3 temperature-programmed desorption (NH3-TPD),H2 temperature-programmed reduction (H2-TPR),N2 adsorption/desorption,and CO-chemisorption.The catalytic activity and the resistance to water poisoning of the prepared Pd catalysts were tested in a simulated exhaust gas from lean-burn natural gas vehicles with and without water vapor.The results demonstrated that the modified supports had an apparent effect on the performance of Pd catalysts,compared with the Pd catalyst supported on the unmodified ZrAl.The addition of ZnO or Y2O3 promoted the conversion of CH4.In the absence of water vapor,Pd/ZnZrAl exhibited the best activity for CH4 conversion with the light-off temperature (T50) of 275 ℃ and the complete conversion temperature (T90) of 314 ℃,respectively.However,in the presence of water vapor,Pd/YZrAl was the best one over which the light-off temperature (T50) of methane was 339 ℃ and the complete conversion temperature (T90) was 371 ℃.These results indicated that Pd catalyst supported on the modified composite ZrAl support showed excellent catalytic activity at low temperature and high resistance to H2O poisoning for the exhaust purification of lean-burn natural gas vehicles.

  8. The performance of a monolithic catalytic converter of automobile exhaust gas with oscillatory feeding of CO, NO, and O{sub 2}. A modelling study

    Energy Technology Data Exchange (ETDEWEB)

    Nievergeld, A.J.L.; Hoebink, J.H.B.J.; Marin, G.B. [Lab. voor Chemische Technologie, Eindhoven Univ. of Technology, Eindhoven (Netherlands)

    1995-12-31

    An isothermal monolithic catalytic converter of automobile exhaust gas was modelled in order to assess the effects of oscillatory feeding of CO, O{sub 2} and NO on the performance of the reactor. The influence of the temperature, frequency, and amplitude on the time average conversions was investigated. An improvement relative to the steady state conversion of 8% for CO and 30% for NO can be obtained. An explanation is given in terms of strongly changing surface coverage during cycling of the feed concentrations. 9 figs., 5 tabs., 16 refs.

  9. On exhaust emissions from petrol-fuelled passenger cars at low ambient temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Laurikko, J. [VTT Energy, Espoo (Finland). Energy Use

    1998-11-01

    The study at hand deals with regulated and unregulated exhaust emissions from petrol-fuelled cars at low ambient temperatures with present-day or near-future exhaust after treatment systems. The subject has been investigated at VTT over a decade and this report compiles data from various sub-studies carried out between the years 1993 - 1997. Each one of them viewed different aspects of the phenomenon, like determining the low-temperature response of today`s new cars employing three-way catalytic converters or assessing the long-term durability and the influence of vehicle mileage upon the low-temperature emissions performance. Within these studies, together more than 120 cars of model years from 1990 to 1997 have been tested. Most of them were normal, in-service vehicles with total mileages differing between only a few thousand kilometres for new cars up to 80,000 km or even more for the in-use vehicles. Both the US FTP75 and the European test cycle have been employed, and the ambient temperatures ranged from the baseline (+22 deg C) down to +- O deg C, -7 deg C and in some cases even to -20 deg C. The studies attested that new cars having today`s advanced emissions control systems produced fairly low levels of emissions when tested in conditions designated in the regulations that are the basis of the current new-vehicle certification. However, this performance was not necessarily attained at ambient temperatures that were below the normative range. Fairly widespread response was recorded, and cars having almost equal emissions output at baseline could produce largely deviating outcomes in low-temperature conditions. On average, CO and HC emissions increased by a factor of five to 10, depending on the ambient temperature and vehicle type. However, emissions of NO{sub x} were largely unaffected. Apart from these regulated emissions, many unregulated species were also determined, either by using traditional sampling and chromatography methods or on-line, employing

  10. Study of an exhaust gas recirculation equipped micro gas turbine supplied with bio-fuels

    International Nuclear Information System (INIS)

    The authors discuss in this paper some aspects related to the employment of liquid and gaseous bio-fuels in a micro-gas turbine. Besides the purpose of checking the effectiveness of methods for supplying the micro-turbine with fuels from renewable sources, the attention is focused on the need of controlling the pollutant emission. To this aim, several solutions are experienced and numerically tested. For the liquid fuel supply, a new shape and location of the main fuel injector is combined with a modified position of the pilot injector. In the case of the biogas fuelling, an external EGR option is considered as activated. Both methods aim at the reduction of the thermal and prompt NO formation by approaching the flameless combustion concept. -- Highlights: • External and internal EGR concepts applied to NOx control from micro gas turbines. • For gaseous fuels: internal EGR is obtained by a proper location of the pilot injector. • For liquid fuels: replacing the original radial injectors with a pressure swirl atomizer. • We apply a CFD based method, after validation with experimental data. • Blends of bio-fuels with fossil fuels promise noticeable benefits

  11. Some implications of applying the theory of the economics of exhaustible resources to oil and gas pricing

    Energy Technology Data Exchange (ETDEWEB)

    Inyang, E.D.; Stultz-Karim, S.P.; Thackeray, F.

    1986-01-01

    The theory of the economics of exhaustible resources is reviewed and discussed in terms of its applicability to the complex structure of the international petroleum industry. Particular attention is given to the implications of uncertainty in reserves estimations for corporate, public, and financial institutions which have the responsibilities of oil and gas pricing and depletion policy formulation. A modification of the model of the economics of exhaustible resources under a freely competitive market structure is analyzed to determine the effect of uncertainty in reserves estimations on the optimal net price and on depletion profiles. The uncertainty in the resultant time until economic exhaustion and the discount present value is found to be directly proportional to the uncertainty in the reserves estimations. These results should be carefully considered in the difficult conflicts between short-term profit maximization and long-term social objectives in the formulation of public and private pricing and depletion policies.

  12. Convolution Sum Discrete Process Neural Network and Its Application in Aeroengine Exhausted Gas Temperature Prediction%卷积和离散过程神经网络及其在航空发动机排气温度预测中的应用

    Institute of Scientific and Technical Information of China (English)

    钟诗胜; 雷达; 丁刚

    2012-01-01

    The changing process of aeroengine exhausted gas temperature (EGT) is affected by complicated nonlinear time varying factors, which make it difficult to construct its mathematic model. To cope with this issue, a convolution sum discrete process neural network (CSDPNN) model is proposed and used for EGT prediction. This model directly utilizes discrete sampling points as input, and uses the convolution sum to deal with the time accumulation process. Compared with the process neural network(PNN)with continuous function inputs, there is ho need to fit the sampling points to get input functions and then to decompose them by orthogonal basis functions which can lead to precision loss. Therefore, this model can a-chieve higher prediction precision. A learning algorithm for this model is also developed, and the model is explained and validated via Mackey-Glass chaos time series prediction. Then, the model is adopted to predict a real EGT time series. The prediction results are compared with results obtained by the process neural network with function inputs and the traditional artificial neural network(ANN), which proves that CSDPNN model has higher precision than the other two networks, and it exhibits good adaptability to EGT prediction. This model offers an effective method for real EGT prediction.%针对航空发动机排气温度的变化过程受复杂非线性时变因素的影响而难以用精确数学模型描述的问题,提出了卷积和离散过程神经网络(CSDPNN)模型,并将其应用于航空发动机排气温度(EGT)预测.该模型以离散样本作为直接输入,采用卷积和算法实现对时间累积效应的处理.相较于以连续函数作为输入的过程神经网络(PNN),不需要拟合离散样本得到连续函数后进行正交基展开,减少了精度损失,具有更高的预测精度.给出了卷积和离散过程神经网络模型的学习算法,并通过对Mackey-Glass混沌时间序列的预测对提出的方法进行应用说明

  13. Combustion and exhaust emission characteristics of a compression ignition engine using liquefied petroleum gas-Diesel blended fuel

    International Nuclear Information System (INIS)

    Towards the effort of reducing pollutant emissions, especially smoke and nitrogen oxides, from direct injection (DI) Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. The use of liquefied petroleum gas (LPG) as an alternative fuel is a promising solution. The potential benefits of using LPG in Diesel engines are both economical and environmental. The high auto-ignition temperature of LPG is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under LPG-Diesel blended fuel conditions, using LPG-Diesel blended fuels with various blended rates (0%, 10%, 20%, 30%, 40%). Comparative results are given for various engine speeds and loads for conventional Diesel and blended fuels, revealing the effect of blended fuel combustion on engine performance and exhaust emissions

  14. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Pollack, B.R.

    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 {mu}m 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.

  16. Reducing the CO2 emissions from fossil fuel power plans by exhaust gas treatment

    International Nuclear Information System (INIS)

    The emission of carbon dioxide (CO2) and other pollutants which result from burning fossil fuels has been identified as the major contributor to global warming and climate change. However, for the short term, at least for the next 10-20 years, the world will continue to rely on fossil fuels as the source of primary energy. The challenge for the fossil the fuel industry is to find cost-effective solutions that will reduce the release of CO2 and other pollutants into the atmosphere. The focus of this paper is on the ability to treat the exhaust gas from fossil fuel power plants in order to capture and store the CO2 and remove the other pollutants such as SOx and NOx which are released into the atmosphere. In summary, capture/separation costs represent the largest financial impediment for this type of plants. Hence, efficient, cost-effective capture/separation technologies need to be developed to allow their large-scale use. (author)

  17. Robust control of speed and temperature in a power plant gas turbine.

    Science.gov (United States)

    Najimi, Ebrahim; Ramezani, Mohammad Hossein

    2012-03-01

    In this paper, an H(∞) robust controller has been designed for an identified model of MONTAZER GHAEM power plant gas turbine (GE9001E). In design phase, a linear model (ARX model) which is obtained using real data has been applied. Since the turbine has been used in a combined cycle power plant, its speed and also the exhaust gas temperature should be adjusted simultaneously by controlling fuel signals and compressor inlet guide vane (IGV) position. Considering the limitations on the system inputs, the aim of the control is to maintain the turbine speed and the exhaust gas temperature within desired interval under uncertainties and load demand disturbances. Simulation results of applying the proposed robust controller on the nonlinear model of the system (NARX model), fairly fulfilled the predefined aims. Simulations also show the improvement in the performance compared to MPC and PID controllers for the same conditions.

  18. Temperature Controlled Filamentation in Argon Gas

    Institute of Scientific and Technical Information of China (English)

    CAO Shi-Ying; KONG Wei-Peng; SONG Zhen-Ming; QIN Yu; LI Ru-Xin; WANG Qing-Yue; ZHANG Zhi-Gang

    2008-01-01

    Temperature controlled filamentation is experimentally demonstrated in a temperature gradient gas-filled tube.The proper position of the tube is heated by a furnace and two ends of the tube are cooled by air. The experimental results show that multiple filaments are shrunken into a single fila.ment or no filament only by increasing the temperature at the beginning of the filament. This technique offers another degree of freedom of controlling the filamentation and opens a new way for intense monocycle pulse generation through gradient temperature in a noble gas.

  19. Temperature Modulation of a Catalytic Gas Sensor

    OpenAIRE

    Eike Brauns; Eva Morsbach; Sebastian Kunz; Marcus Baeumer; Walter Lang

    2014-01-01

    The use of catalytic gas sensors usually offers low selectivity, only based on their different sensitivities for various gases due to their different heats of reaction. Furthermore, the identification of the gas present is not possible, which leads to possible misinterpretation of the sensor signals. The use of micro-machined catalytic gas sensors offers great advantages regarding the response time, which allows advanced analysis of the sensor response. By using temperature modulation, additi...

  20. Reduction of the exhaust gas emissions during warm up by improving the mixture preparation of spark-ignition engines

    International Nuclear Information System (INIS)

    During warm-up the engine emits the highest concentration of exhaust gas emissions. An improvement of the atomization behaviour of the injected fuel should lead to a good mixture preparation in the manifold and combustion chamber and further to lower exhaust gas emissions during warm up. During these investigations it was found out that the build-up of fuel film in the manifold of cold spark-ignition engines can not be prevented. But by injecting the fuel at the open inlet valve it is possible to reduce the fuel film. The injection of extremely finely atomized fuel at the open inlet valve leads to a better mixture preparation with smaller fuel dropplets in the manifold and combustion chamber. This again leads, during warm-up of the spark ignition engine, to a reduction of the HC emissions of 30% and the CO emissions of 50%. (author)

  1. Application of exhaust gas fuel reforming in diesel and homogeneous charge compression ignition (HCCI) engines fuelled with biofuels

    OpenAIRE

    A. Megaritis; Yap, D

    2008-01-01

    This is the post-print version of the final paper published in Energy. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2007 Elsevier B.V. This paper documents the application of exhaust gas fuel reforming ...

  2. Effects of Gas Velocity and Temperature on Nitric Oxide Conversion in Simulated Catalytic Converter

    Directory of Open Access Journals (Sweden)

    Sathaporn Chuepeng

    2012-01-01

    Full Text Available Problem statement: Gaseous emissions from gasoline engine such as carbon monoxide, unburned hydrocarbon and nitrogen oxides were usually reduced in three-way catalytic converter simultaneously around theoretical fuel and air combustion. Engine speed and load and other parameters were varied over a wide range of operating conditions, resulting in different exhaust gas composition and condition intake into catalytic converter. This work was studied the conversion of Nitric Oxide (NO in exhaust gas catalytic converter affected by gas velocity and inlet temperature using numerical modeling. Approach: The simulation was based on a one-dimensional time-dependent model within a single monolith channel of the converter. Upon certain assumptions, the study was considered heterogeneous combustion reaction between gas and solid phases based on lumped kinetic reactions. In this study, constants and variables used for mass and heat transfers were dependent on gas or solid phase temperature and mole fraction. Finite difference scheme incorporated with the generated computer code was established for solving species and energy balances within gas and solid phases. Results: The NO conversion was increased with transient period in initial and reached steady state at different values. The lower inlet gas temperature was resulted in lesser NO conversion at the same inlet NO concentration and gas velocity. The light-off temperatures were up to 520 K and a sudden rise in NO conversion was from 550-605 K and decreasing onwards, generating working temperature window. NO conversion increased throughout the catalyst bed from the inlet and the conversion decreased as the gas velocity increased. Conclusion/Recommendations: Gas space velocity and gas temperature intake to the converter affected the NO conversion over the time and the axial distance from the catalyst bed inlet. The numerical results have summarily demonstrated a good approximation compared to experimental

  3. Thermodynamic and economic performances optimization of an organic Rankine cycle system utilizing exhaust gas of a large marine diesel engine

    International Nuclear Information System (INIS)

    Highlights: • A new parameter is proposed for optimizing economic performance of the ORC system. • Maximal thermodynamic and economic performances of an ORC system are presented. • The corresponding operating pressures in turbine of optimum thermodynamic and economic performances are investigated. • An optimal effectiveness of pre-heater is obtained for the ORC system. - Abstract: The aim of this study is to investigate the thermodynamic and economic performances optimization for an ORC system recovering the waste heat of exhaust gas from a large marine diesel engine of the merchant ship. Parameters of net power output index and thermal efficiency are used to represent the economic and thermodynamic performances, respectively. The maximum net power output index and thermal efficiency are obtained and the corresponding turbine inlet pressure, turbine outlet pressure, and effectiveness of pre-heater of the ORC system are also evaluated using R1234ze, R245fa, R600, and R600a. Furthermore, the analyses of the effects of turbine inlet temperature and cooling water temperature on the optimal economic and thermodynamic performances of the ORC system are carried out. The results show that R245fa performs the most satisfactorily followed by R600, R600a, and R1234ze under optimal economic performance. However, in the optimal thermodynamic performance evaluations, R1234ze has the largest thermal efficiency followed by R600a, R245fa, and R600. The payback periods will decrease from 0.5 year for R245fa to 0.65 year for R1234ze respectively as the system is equipped with a pre-heater. In addition, compared with conventional diesel oil feeding, the proposed ORC system can reduce 76% CO2 emission per kilowatt-hour

  4. 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.

  5. 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

  6. 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.

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

    OpenAIRE

    Branko Lalić; Gojmir Radica; Nikola Račić

    2016-01-01

    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 furth...

  8. Effect of Exhaust Gas Recirculation and Combustible Oxygen Mass Fraction on Emission Index of NOx for Counterflow Methane/Air Diffusion Flames

    OpenAIRE

    Sane, Mugdha S

    2013-01-01

    Exhaust gas recirculation has been proven to be an effective method of reducing emissions of oxides of nitrogen (NOx) from internal combustion engines. The present study validates this effect through flame simulations using detailed chemistry. Counterflow methane/air diffusion flames were simulated in one dimension in physical space using GRI-Mech 3.0 detailed chemistry mechanism, thermal, and transport data. The influence of Exhaust Gas Recirculation (EGR) on the flame structure and NOx emis...

  9. Thermally grown oxide films and corrosion performance of ferritic stainless steels under simulated exhaust gas condensate conditions

    International Nuclear Information System (INIS)

    Highlights: • Five ferritic stainless steels with dissimilar composition included. • Thermal oxide films and performance under exhaust gas condensate conditions studied. • Oxide films grown at 300 and 600 °C show differences in structure and properties. • Performance of alloys with >11.5 wt.% Cr is related to elements Ti, Si, Nb and Mo. • Compositional optimization requires knowledge on several linked processes. - Abstract: Five ferritic stainless steels are characterized in terms of thermally grown oxide films and corrosion performance under simulated exhaust gas condensate conditions. Oxide films developed at 300 °C show only little variation in microstructure and properties between the alloys, whereas those evolved at 600 °C exhibit clear differences. Especially in alloys with >11.5 wt.% chromium, the presence and distribution of such alloying elements as titanium, silicon, niobium and molybdenum are crucial for the film properties and the overall corrosion performance. The results may be exploited in the compositional optimization of the alloys for the cold-end components of automotive exhaust system

  10. Estimation of exhaust gas aerodynamic force on the variable geometry turbocharger actuator: 1D flow model approach

    International Nuclear Information System (INIS)

    Highlights: • Estimation of aerodynamic force on variable turbine geometry vanes and actuator. • Method based on exhaust gas flow modeling. • Simulation tool for integration of aerodynamic force in automotive simulation software. - Abstract: This paper provides a reliable tool for simulating the effects of exhaust gas flow through the variable turbine geometry section of a variable geometry turbocharger (VGT), on flow control mechanism. The main objective is to estimate the resistive aerodynamic force exerted by the flow upon the variable geometry vanes and the controlling actuator, in order to improve the control of vane angles. To achieve this, a 1D model of the exhaust flow is developed using Navier–Stokes equations. As the flow characteristics depend upon the volute geometry, impeller blade force and the existing viscous friction, the related source terms (losses) are also included in the model. In order to guarantee stability, an implicit numerical solver has been developed for the resolution of the Navier–Stokes problem. The resulting simulation tool has been validated through comparison with experimentally obtained values of turbine inlet pressure and the aerodynamic force as measured at the actuator shaft. The simulator shows good compliance with experimental results

  11. Effect of ejector dilutors on measurements of automotive exhaust gas aerosol size distributions

    International Nuclear Information System (INIS)

    Ejector dilutors have long been used for automotive exhaust particle sampling, as they can offer a low-cost option for stable dilution. In an ejector dilutor, pressurized air expanding in the periphery of a nozzle draws in and mixes with an exhaust sample which is then led to analytical equipment. The combination of processes involved may lead to particle losses which can affect the measurement. This study examines the losses of diesel exhaust particles of different characteristics (nucleation mode, non-volatile accumulation mode, internally and externally mixed accumulation mode) when these are sampled through an ejector dilutor. A scanning mobility particle sizer (SMPS), an electrical low-pressure impactor and a diffusion charger were used as analytical equipment to characterize losses with different instruments. Particle losses were found negligible for all practical applications of diesel exhaust aerosol sampling. Also, the sampling outlet and the operating pressure of the ejector dilutor were found to have a non-measurable effect on the distribution shape. Some variation of the labile nucleation mode particles was attributed to evaporation within the SMPS rather than an ejector effect, and this was confirmed by sampling solid NaCl particles in the same size range. The study further confirms the usability of ejector dilutors for exhaust particle sampling and dilution

  12. Catalysts, systems and methods to reduce NOX in an exhaust gas stream

    Science.gov (United States)

    Castellano, Christopher R.; Moini, Ahmad; Koermer, Gerald S.; Furbeck, Howard

    2010-07-20

    Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having an SCR catalyst comprising silver tungstate on an alumina support. The emissions treatment system may be used for the treatment of exhaust streams from diesel engines and lean burn gasoline engines. An emissions treatment system may further comprise an injection device operative to dispense a hydrocarbon reducing agent upstream of the catalyst.

  13. Low-temperature gas from marine shales: wet gas to dry gas over experimental time

    OpenAIRE

    Jarvie Daniel M; Mango Frank D

    2009-01-01

    Abstract Marine shales exhibit unusual behavior at low temperatures under anoxic gas flow. They generate catalytic gas 300° below thermal cracking temperatures, discontinuously in aperiodic episodes, and lose these properties on exposure to trace amounts of oxygen. Here we report a surprising reversal in hydrocarbon generation. Heavy hydrocarbons are formed before light hydrocarbons resulting in wet gas at the onset of generation grading to dryer gas over time. The effect is moderate under ga...

  14. 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

  15. The impact of using biodiesel/marine gas oil blends on exhaust emissions from a stationary diesel engine.

    Science.gov (United States)

    Karavalakis, G; Tzirakis, E; Mattheou, L; Stournas, S; Zannikos, F; Karonis, D

    2008-12-01

    The purpose of this work was to investigate the impact of marine gas oil (MGO)/biodiesel blends on the exhaust emissions and fuel consumption in a single cylinder, stationary, diesel engine. Three different origins of biodiesel were used as the blending feedstock with the reference MGO, at proportions of 5 and 10% by volume. Methyl esters were examined according to the automotive FAME standard EN 14214. The baseline MGO and biodiesel blends were examined according to ISO 8217:2005 specifications for the DMA category. Independently of the biodiesel used, a decrease of PM, HC, CO and CO(2) emissions was observed. Emissions of NO(x) were also lower with respect to MGO. This reduction in NO(x) may be attributed to some physicochemical properties of the fuels applied, such as the higher cetane number and the lower volatility of methyl esters. Reductions in PM for biodiesel blends were lower in the exhaust than those of the reference fuel which was attributed to the oxygen content and the near absence of sulphur and aromatics compounds in biodiesel. However, a slight increase in fuel consumption was observed for the biodiesel blends that may be tolerated due to the exhaust emissions benefits. Brake thermal efficiency was also determined. Unregulated emissions were characterized by determining the soluble organic fraction content of the particulate matter. PMID:18988104

  16. A well-based cost function and the economics of exhaustible resources: The case of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Chermak, J.M. [Naval Postgraduate School, Monterey, CA (United States); Patrick, R.H. [Rutgers Univ., Newark, NJ (United States)

    1995-03-01

    A cost function for natural gas production is estimated, using a pool of data from 29 wells. Statistically exact tests are performed for parameter stability across locations, formations, wells, and producing firms. Costs are determined to be inversely related to remaining recoverable reserves, and marginal costs of production are decreasing in all cases. Theoretical implications of these cost characteristics on optimal exhaustible resource extraction are analyzed. Although marginal cost is decreasing, production effects on the resource stock imply that an interior production path may be optimal. Conditions under which production optimally occurs at the capacity bound are delineated, and optimal interior production paths are characterized. 21 refs., 2 tabs.

  17. Operating limitations due to low gas temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bruschi, R.; Ghiselli, W.; Spinazze, M.

    1995-12-31

    A number of projects concerning continental links for the transport of treated natural gas over long distance, both on and offshore, have been implemented during the last few years or are currently being implemented. The long trunklines in North America and subsea trunklines planned or already in operation in the North Sea, are outstanding examples of such long distance transmission of gas in large diameter pipelines operated at high pressure. The development of such network has paid special attention to the effects that low temperature resulting from the transportation process may imply in terms of pipe structural integrity and environmental impact. Scope of this paper is to discuss operating limitations due to low gas temperature. New project scenarios are presented in a brief introduction. The fluido-thermo-dynamic background for the development of low temperatures are outlined. Finally some topics relevant to structural integrity are discussed in particular such as the pipe steel behaviour at low temperature, the prediction techniques of the ice bulb growth around the pipe, the interactions of the cold line with the soil and the consequences due to the differential compliancy of the pipeline towards points of fixity (in-line valves/tees or fixed plants). 30 refs., 22 figs., 1 tab.

  18. 40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Fleet average non-methane organic gas....1710-99 Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and light light-duty trucks. (a) Fleet average NMOG standards and compliance. (1) Each manufacturer...

  19. Polymer spiral film gas-liquid heat exchanger for waste heat recovery in exhaust gases

    OpenAIRE

    Breton, Antoine

    2012-01-01

    In this master thesis report the development of an innovative spiral heat exchanger based on polymer materials is described. Building prototypes, erection of a test bench and firsts tests of the heat exchanger are presented. The heat exchanger prototype survived all tests especially several days in contact with aggressive gases. A facility integrating a Diesel exhaust gases production has been developed to test this heat exchanger design. Performance results obtained during the tes...

  20. Prediction of emissions and exhaust temperature for direct injection diesel engine with emulsified fuel using ANN

    OpenAIRE

    KÖKKÜLÜNK, Görkem; Akdoğan, Erhan; AYHAN, Vezir

    2012-01-01

    Exhaust gases have many effects on human beings and the environment. Therefore, they must be kept under control. The International Convention for the Prevention of Pollution from Ships (MARPOL), which is concerned with the prevention of marine pollution, limits the emissions according to the regulations. In Emission Control Area (ECA) regions, which are determined by MARPOL as ECAs, the emission rates should be controlled. Direct injection (DI) diesel engines are commonly used as a prop...

  1. Exhaust Gas Recirculation Technology (EGR)%废气再循环系统EGR的探讨

    Institute of Scientific and Technical Information of China (English)

    桂林; 孙亮

    2012-01-01

    With the continuous improvement of economic level and living standards, an explosion of car makes easier to people in the life, but also causes serious air pollution. Exhaust gas recirculation technology (EGR) is the more effective emission control means. By a typical structure introduction, this paper gives an indepth analysis about how exhaust gas recirculation system works and the control strategies.%随着经济水平、生活水平的不断提高,汽车保有量激增,在给人们生活带来便利的同时,也造成了十分严重的大气污染。废气再循环技术(EGR),是目前比较有效地尾气控制手段。通过典型结构的介绍,深入分析废气再循环系统的工作原理、控制策略等。

  2. 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.

  3. The Evolution of High Temperature Gas Sensors.

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, F. H. (Fernando H.); Brosha, E. L. (Eric L.); Mukundan, R. (Rangachary)

    2001-01-01

    Gas sensor technology based on high temperature solid electrolytes is maturing rapidly. Recent advances in metal oxide catalysis and thin film materials science has enabled the design of new electrochemical sensors. We have demonstrated prototype amperometric oxygen sensors, nernstian potentiometric oxygen sensors that operate in high sulfur environments, and hydrocarbon and carbon monoxide sensing mixed potentials sensors. Many of these devices exhibit part per million sensitivities, response times on the order of seconds and excellent long-term stability.

  4. 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

    : publication of two new technical papers by Clemson detailing the control strategies used for the EGR system control. The two papers was published in the 2016 SAE World Congress in April 2016. The titles of each paper are, “Physics-Based Exhaust Pressure and Temperature Estimation for Low Pressure EGR Control in Turbocharged Gasoline Engines,” by K. Siokos, and “A Control Algorithm for Low Pressure – EGR Systems using a Smith Predictor with Intake Oxygen Sensor Feedback”, by R. Koli. All phase III work packages have been completed. The primary work packages in phase III were the following: completion of long-term sensor durability testing, final demonstration of benefits of EGR control w/o sensing, final decision of the second generation sensor development path.

  5. The pilot plant experiment of electron beam irradiation process for removal of NOx and SOx from sinter plant exhaust gas in the iron and steel industry

    International Nuclear Information System (INIS)

    Air pollution problem has become more important in the progress of industry. Nitrogen oxides (NOx, mostly NO) and sulfur oxides (SOx, mostly SO2) which are contained in a sinter plant exhaust gas, are known as serious air pollutants. In such circumstances, an attempt has been made to simultaneously remove NOx and SOx from the sinter plant exhaust gas by means of a new electron beam irradiation process. The process consists of adding a small amount of NH3 to the exhaust gas, irradiating the gas by electron beam, forming ammonium salts by reactions of NOx and SOx with the NH3 and collecting ammonium salts by dry electrostatic precipitator (E.P.). Basic research on the present process had been performed using heavy oil combustion gas. Based on the results research was launched to study the applicability of the process to the treatment of sinter plant exhaust gas. A pilot plant, capable of treating a gas flow of 3000 Nm3/H was set up, and experiments were performed from July 1977 to June 1978. The plant is described and the results are presented. (author)

  6. Power and temperature control of fluctuating biomass gas fueled solid oxide fuel cell and micro gas turbine hybrid system

    Science.gov (United States)

    Kaneko, T.; Brouwer, J.; Samuelsen, G. S.

    This paper addresses how the power and temperature are controlled in a biomass gas fueled solid oxide fuel cell (SOFC) and micro gas turbine (MGT) hybrid system. A SOFC and MGT dynamic model are developed and used to simulate the hybrid system performance operating on biomass gas. The transient behavior of both the SOFC and MGT are discussed in detail. An unstable power output is observed when the system is fed biomass gas. This instability is due to the fluctuation of gas composition in the fuel. A specially designed fuel controller succeeded not only in allowing the hybrid system to follow a step change of power demand from 32 to 35 kW, but also stably maintained the system power output at 35 kW. In addition to power control, fuel cell temperature is controlled by introduction and use of a bypass valve around the recuperator. By releasing excess heat to the exhaust, the bypass valve provided the control means to avoid the self-exciting behavior of system temperature and stabilized the temperature of SOFC at 850 °C.

  7. 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.

  8. Amperometric NOx-sensor for Combustion Exhaust Gas Control. Studies on transport properties and catalytic activity of oxygen permeable ceramic membranes

    International Nuclear Information System (INIS)

    The aim of the research described in this thesis is the development of a mixed conducting oxide layer, which can be used as an oxygen permselective membrane in an amperometric NOx sensor. The sensor will be used in exhaust gas systems. The exhaust gas-producing engine will run in the lean mix mode. The preparation of this sensor is carried out using screen-printing technology, in which the different layers of the sensor are applied successively. Hereafter, a co-firing step is applied in which all layers are sintered together. This co-firing step imposes several demands on the selection of materials. The design specifications of the sensor further include requirements concerning the operating temperature, measurement range and overall stability. The operating temperature of the sensor varies between 700 and 850C, enabling measurement of NOx concentrations between 50 and 1200 ppm with a measurement accuracy of 10 ppm. Concerning the stability of the sensor, it must withstand the exhaust gas atmosphere containing, amongst others, smoke, acids, abrasive particles and sulphur. Because of the chosen lean-mix engine concept, in which the fuel/air mixture switches continuously between lean (excess oxygen) and fat (excess fuel) mixtures, the sensor must withstand alternately oxidising and reducing atmospheres. Besides, it should be resistant to thermal shock and show no cross-sensitivity of NOx with other exhaust gas constituents like oxygen and hydrocarbons. The response time should be short, typically less than 500 ms. Because of the application in combustion engines of cars, the operational lifetime should be longer than 10 years. Demands on the mixed conducting oxide layer include the following ones. The layer should show minimal catalytic activity towards NOx-reduction. The oxygen permeability must be larger than 6.22 10-8 mol/cm2s at a layer thickness between 3-50 μm. Since the mixed conducting oxide layer is coated on the YSZ electrolyte embodiment, the two

  9. Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer

    Directory of Open Access Journals (Sweden)

    M. H. Erickson

    2012-02-01

    Full Text Available A new approach was developed to measure the total abundance of long chain alkanes (C12 and above in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS. These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1, monocyclic aromatics, and an ion group with formula CnH2n−1 (m/z 97, 111, 125, 139. The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 μg m−3 to 100 μg m−3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.

  10. Ejection of toxic and carcinogenic substances along with the exhaust gasses of gas turbine engines and ways of reducing them

    Energy Technology Data Exchange (ETDEWEB)

    Varshavskiy, I.L.; Kanilo, P.M.; Khesina, A.Y.; Ryabeka, V.P.; Smirnov, G.A.

    1981-01-01

    Studies of the amount of carcinogenic substances in exhaust gasses of piston aviation engines showed that the concentration of Benzene (A) tyrene in exhaust gasses is found at a level of 0.5-5 micrograms/m/sup 3/. It increases with an increase of a load, rotation frequency and angle of advance of fuel injection. The maximum concentration of Benzene(A)tyrene is observed in transitional states related to acceleration of the airplane. Measures to reduce the ejection of NO (injection of water into the combustion chamber, the use of water and fuel emulsions, recirculation of the treated gasses into the combustion chamber) relates to an increase of Benzene(a)tyrene ejections. Tests were carried out on an experimental test bed using the gas turbine aviation engine type AI-9 to determine the amount of waste gasses that are carcinogenic and toxic. The Benzene(a)tyrene concentration in waste gasses of piston engines (0.8 micrograms/m/sup 3/) with an increase of the total coefficient of excess air in a combustion chamber increases by a factor of 2 to 4. Enriching the fuel-air mixture with hydrogen in a combustion chamber of a gas turbine engine by adding hydrogen to the primary zone of the combustion chamber simultaneously reduces the concentration of waste gasses, Benzene(a)tyrene and CO. For the AI-25 gas turbine engine the addition of hydrogen in the amount of 5% mass of fuel reduces the ejection of CO by a factor of 2, and that of Benzene(a)tyrene by a factor of 7.

  11. High temperature gas-cooled reactor: gas turbine application study

    International Nuclear Information System (INIS)

    The high-temperature capability of the High-Temperature Gas-Cooled Reactor (HTGR) is a distinguishing characteristic which has long been recognized as significant both within the US and within foreign nuclear energy programs. This high-temperature capability of the HTGR concept leads to increased efficiency in conventional applications and, in addition, makes possible a number of unique applications in both electrical generation and industrial process heat. In particular, coupling the HTGR nuclear heat source to the Brayton (gas turbine) Cycle offers significant potential benefits to operating utilities. This HTGR-GT Application Study documents the effort to evaluate the appropriateness of the HTGR-GT as an HTGR Lead Project. The scope of this effort included evaluation of the HTGR-GT technology, evaluation of potential HTGR-GT markets, assessment of the economics of commercial HTGR-GT plants, and evaluation of the program and expenditures necessary to establish HTGR-GT technology through the completion of the Lead Project

  12. High temperature gas-cooled reactor: gas turbine application study

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    The high-temperature capability of the High-Temperature Gas-Cooled Reactor (HTGR) is a distinguishing characteristic which has long been recognized as significant both within the US and within foreign nuclear energy programs. This high-temperature capability of the HTGR concept leads to increased efficiency in conventional applications and, in addition, makes possible a number of unique applications in both electrical generation and industrial process heat. In particular, coupling the HTGR nuclear heat source to the Brayton (gas turbine) Cycle offers significant potential benefits to operating utilities. This HTGR-GT Application Study documents the effort to evaluate the appropriateness of the HTGR-GT as an HTGR Lead Project. The scope of this effort included evaluation of the HTGR-GT technology, evaluation of potential HTGR-GT markets, assessment of the economics of commercial HTGR-GT plants, and evaluation of the program and expenditures necessary to establish HTGR-GT technology through the completion of the Lead Project.

  13. 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.

  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. Exhaust Gas Analysis and Parametric Study of Ethanol Blended Gasoline Fuel in Spark Ignition Engine

    Directory of Open Access Journals (Sweden)

    Jitendra kumar

    2013-07-01

    Full Text Available It is well known that the future availability of energy resources, as well as the need for reducing CO2 emissions from the fuels used has increased the need for the utilization of regenerative fuels. This research is done taking commercial gasoline as reference which is originally blended with 5% ethanol. Hence 5%, 10%, 15%, 20% ethanol blended with Gasoline initially was tested in SI engines. Physical properties relevant to the fuel were determined for the four blends of gasoline. A four cylinder, four stroke, varying rpm, Petrol (MPFI engine was tested on blends containing 5%,10%,15%,20% ethanol and performance characteristics, and exhaust emissions were evaluated. Even though higher blends can replace gasoline in a SI engine, results showed that there is a reduction in exhaust gases, such as HC, O2, CO, CO2 and increase in Brake Thermal Efficiency on blending. Hence we can conclude from the result that using 10% ethanol blend is most effective and we can utilize it for further use in SI engines with little constraint on material used to sustain little increase in pressure.

  16. Bicycle Painting Exhaust Gas Treatment Technology Comparison%自行车涂装废气治理技术的对比

    Institute of Scientific and Technical Information of China (English)

    杜万义; 张晓燕

    2015-01-01

    The exhaust gas of bicycle spraying mainly contains two parts. The first part is the mist particles which appear during spraying process. The second part is VOC which appear during the process of spraying and drying. This paper describes the main treatment method of the exhaust gas during bicycle spraying.%自行车涂装废气主要有两部分,一是喷涂过程中产生的漆雾颗粒物,二是喷涂和烘干过程中产生的VOC。本文阐述了涂装废气的治理主要方法。

  17. Market structure and exhaustible resources: The case of natural gas and crude oil in California

    Science.gov (United States)

    Czastkiewicz, Carolina

    Using a dataset of natural gas and crude oil production in the state of California, evidence shows overextraction incentives among market participants that shared a common pool. Due to these incentives the supply of gas and crude oil extraction tends to become more inelastic as the number of firms in the pool increases. Using an instrumental variables estimation of the supply function, the results show that the common pool externality caused an average overproduction rate of 11% and 4% over the 1977--2001 period, in natural gas and crude oil, respectively. These figures imply 1 year and 4 years of additional production for natural gas and crude oil, respectively.

  18. Bimodular high temperature planar oxygen gas sensor

    Directory of Open Access Journals (Sweden)

    Xiangcheng eSun

    2014-08-01

    Full Text Available A bimodular planar O2 sensor was fabricated using NiO nanoparticles (NPs thin film coated yttria-stabilized zirconia (YSZ substrate. The thin film was prepared by radio frequency (r.f. magnetron sputtering of NiO on YSZ substrate, followed by high temperature sintering. The surface morphology of NiO nanoparticles film was characterized by atomic force microscopy (AFM and scanning electron microscopy (SEM. X-ray diffraction (XRD patterns of NiO NPs thin film before and after high temperature O2 sensing demonstrated that the sensing material possesses a good chemical and structure stability. The oxygen detection experiments were performed at 500 °C, 600 °C and 800 °C using the as-prepared bimodular O2 sensor under both potentiometric and resistance modules. For the potentiometric module, a linear relationship between electromotive force (EMF output of the sensor and the logarithm of O2 concentration was observed at each operating temperature, following the Nernst law. For the resistance module, the logarithm of electrical conductivity was proportional to the logarithm of oxygen concentration at each operating temperature, in good agreement with literature report. In addition, this bimodular sensor shows sensitive, reproducible and reversible response to oxygen under both sensing modules. Integration of two sensing modules into one sensor could greatly enrich the information output and would open a new venue in the development of high temperature gas sensors.

  19. The Use of Exhaust Gas Recirculation to Optimize Fuel Economy and Minimize Emission in Engines Operating on E85 Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ko-Jen

    2011-12-31

    This report summarizes activities conducted for the project “The Use of Exhaust Gas Recirculation to Optimized Fuel Economy and Minimize Emissions in Engines Operating on E85 Fuel” under COOPERATIVE AGREEMENT NUMBER DE-FC26-07NT43271, which are as outlined in the STATEMENT OF PROJECT OBJECTIVES (SOPO) dated March 2007 and in the supplemental SOPO dated October 2010. The project objective was to develop and demonstrate an internal combustion engine that is optimized for E85 (85% ethanol and 15% gasoline) fuel operation to achieve substantially improved fuel economy while operating with E85 fuel and that is also production viable in the near- to medium-term. The key engine technology selected for research and development was turbocharging, which is known to improve fuel economy thru downsizing and is in particular capable of exploiting ethanol fuel’s characteristics of high octane number and high latent heat of vaporization. The engine further integrated synergistic efficiency improving technologies of cooled exhaust gas recirculation (EGR), direct fuel injection and dual continuously variable intake and exhaust cam phasers. On the vehicle level, fuel economy was furthered thru powertrain system optimization by mating a state-of-the-art six-speed automatic transmission to the engine. In order to achieve the project’s objective of near- to medium-term production viability, it was essential to develop the engine to be flex-fuel capable of operating with fuels ranging from E0 (0% ethanol and 100% gasoline) to E85 and to use three-way type of catalyst technology for exhaust aftertreatment. Within these scopes, various technologies were developed through systems approach to focus on ways to help accelerate catalyst light-off. Significant amount of development took place during the course of the project within General Motors, LLC. Many prototype flex-fuel engines were designed, built and developed with various hardware configurations selected to achieve the project

  20. 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.

  1. Effects of temperature conditions in a gas collector on operation of primary and secondary gas coolers

    Energy Technology Data Exchange (ETDEWEB)

    Chuishchev, V.M.; Selivanova, Z.G.; Vasyuta, V.I.

    1988-04-01

    Discusses composition of coal gas leaving coke ovens and temperature effects on its composition in a gas collector and cooling systems. Effects of coal gas temperature ranging from 78 to 90 C on operation of cooling systems are analyzed: cooling intensity, naphthalene buildup, etc. Analyses show that coal gas temperature fluctuations from 80 to 90 C do not influence gas collector operation, whereas operation of primary gas coolers is influenced by gas collector operation. When coal gas temperature is reduced from 88 to 80 C intensity of coal tar accumulation increases 2 times and that of naphthalene increases 5 to 6 times. Temperature of coal gas leaving the primary coolers ranges from 35 to 40 C. Types of primary coal gas coolers, their operation and performance are comparatively evaluated. Effects of gas cooler design on efficiency of coal tar separation from coal gas are discussed. 5 refs.

  2. Development of High Temperature Gas Sensor Technology

    Science.gov (United States)

    Hunter, Gary W.; Chen, Liang-Yu; Neudeck, Philip G.; Knight, Dak; Liu, Chung-Chiun; Wu, Quing-Hai; Zhou, Huan-Jun

    1997-01-01

    The measurement of engine emissions is important for their monitoring and control. However, the ability to measure these emissions in-situ is limited. We are developing a family of high temperature gas sensors which are intended to operate in harsh environments such as those in an engine. The development of these sensors is based on progress in two types of technology: (1) The development of SiC-based semiconductor technology; and (2) Improvements in micromachining and microfabrication technology. These technologies are being used to develop point-contact sensors to measure gases which are important in emission control especially hydrogen, hydrocarbons, nitrogen oxides, and oxygen. The purpose of this paper is to discuss the development of this point-contact sensor technology. The detection of each type of gas involves its own challenges in the fields of materials science and fabrication technology. Of particular importance is sensor sensitivity, selectivity, and stability in long-term, high temperature operation. An overview is presented of each sensor type with an evaluation of its stage of development. It is concluded that this technology has significant potential for use in engine applications but further development is necessary.

  3. Device for the removal of sulfur dioxide from exhaust gas by pulsed energization of free electrons

    International Nuclear Information System (INIS)

    The performance of a new device using pulsed streamer corona for the removal of sulfur dioxide from humid air has been evaluated. The pulsed streamer corona produced free electrons which enhance gas-phase chemical reactions, and convert SO2 to sulfuric acid mist. The SO2 removal efficiency was compared with that of the electron-beam flue-gas treatment process. The comparison demonstrates the advantage of the novel device

  4. Effects of Gas Temperature Fluctuation on the Soot Formation Reactions

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying; ZHANG Jian

    2013-01-01

    The effects of gas temperature fluctuations on soot formation and oxidation reactions are investigated numerically in a reacting flow.The instantaneous variations of soot mass fraction with time are obtained under the time-averaged gas temperature of 1500 1700 K.The simulation results show that the gas temperature fluctuation has obvious influence on the instantaneous processes of soot formation and oxidation.Within the present range of gas temperature,the gas temperature fluctuation results in generally lower soot mass fraction comparing to that without gas temperature fluctuation.The increase in the fluctuation amplitude of gas temperature leads to decrease in time-averaged soot mass fraction and increase in time-averaged soot particle number density.

  5. Control of PCDDs/PCDFs, PCBs and PAHs emissions in exhaust of landfill gas fed engines

    Energy Technology Data Exchange (ETDEWEB)

    Idczak, F.; Dengis, P.; Duchateau, P.; Petitjean, S. [ISSeP, Liege (Belgium)

    2004-09-15

    Wallonia in Belgium, like many countries around the world, planned to reduce amounts of waste generated by human activity and stored in landfills. Since they experienced a couple of crisis situations in the past, both with former and presently used landfill sites, authorities launched a demanding landfill monitoring program which covers now 9 out of the 10 major sites. Biogas produced in these landfills are collected and eliminated in two different ways. Either simply burned in a flare, or, when the methane grade and flow are high enough, the biogas can be burned in electricity producing engines. This later use represents an energy recovery from the waste. In the context of difficulty for landfill sites to be accepted by the public (the well-known NIMBY phenomenon), the question has been raised whether combustion of the biogas did not entail production of dioxins and other polyaromatic compounds. For the exhaust gases of engines operated with biogas, a check on the presence of dioxins and associated organic pollutants, composed of three different runs or days of sampling for each of 5 landfill sites was performed upon demand of responsible authorities.

  6. Inhalation of diesel engine exhaust affects spermatogenesis in growing male rats; Diesel enigne hai gas bakuro ni yoru seicho yusei rat no seishi keisei eno eiky

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, A. [Japan Automobile Research Institute Inc., Tsukuba (Japan)

    2000-04-01

    The paper investigated effects of the exposure of diesel engine exhaust on internal secretion function of genital organs of rats being in growth. Exposure tests were divided into a group of exposing rats to total exhaust gas (TG), a group of exposing rats to particulate-free exhaust gas (PFG), and a group of exposing rats to clean air (comparison group). The tests were carried out for 6 hours/day, for 5 days/week, and for 3 months from the birth. As to the weight at the time of finishing tests, there were no significant differences in weights of testicle and epididymis in each group. About the concentration of male/female sex hormones in serum, the values were significantly higher in TG and PFG groups than the comparison group. The follide stimulating hormone significantly decreased in both exposure groups as compared with the comparison group. The luteinizing hormone significantly decreased in TG group as compared with the comparison group and PFG group. Further, the sperm productivity and testicle hyaluronidase activity significantly decreased in both exhaust exposure groups as compared with the comparison group. It is indicated that the diesel engine exhaust stimulates the secretion of adrenal cortical hormone, reduces emission of gonadotropic hormone, and controls the spermatogenesis of rats. (NEDO)

  7. 14 CFR 29.1123 - Exhaust piping.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 29.1123 Section 29.1123... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust... by operating temperatures. (b) Exhaust piping must be supported to withstand any vibration...

  8. 14 CFR 27.1123 - Exhaust piping.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 27.1123 Section 27.1123... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping... operating temperatures. (b) Exhaust piping must be supported to withstand any vibration and inertia loads...

  9. Gas velocity and temperature near a liquid rocket injector face

    Science.gov (United States)

    Boylan, D. M.; Ohara, J.

    1973-01-01

    The gas flow near the injector of a liquid propellant rocket was investigated by rapidly inserting butt-welded platinum-platinum rhodium thermocouples through the injector into the chamber. The transient responses of the thermocouples were analyzed to determine average gas temperatures and velocities. A method of fitting exponential curves to repeated measurements of the transient temperature at several positions near the injector face produced consistent results. Preliminary tests yielded gas flow directions and gas compositions at the injector face. Average gas temperatures were found to be between 3100 (1700) and 3500 F (1950 C) and the average gas velocities between 550 (170) and 840 feet/second (260 m/sec).

  10. A New Ductility Exhaustion Model for High Temperature Low Cycle Fatigue Life Prediction of Turbine Disk Alloys

    Science.gov (United States)

    Zhu, Shun-Peng; Huang, Hong-Zhong; Li, Haiqing; Sun, Rui; Zuo, Ming J.

    2011-06-01

    Based on ductility exhaustion theory and the generalized energy-based damage parameter, a new viscosity-based life prediction model is introduced to account for the mean strain/stress effects in the low cycle fatigue regime. The loading waveform parameters and cyclic hardening effects are also incorporated within this model. It is assumed that damage accrues by means of viscous flow and ductility consumption is only related to plastic strain and creep strain under high temperature low cycle fatigue conditions. In the developed model, dynamic viscosity is used to describe the flow behavior. This model provides a better prediction of Superalloy GH4133's fatigue behavior when compared to Goswami's ductility model and the generalized damage parameter. Under non-zero mean strain conditions, moreover, the proposed model provides more accurate predictions of Superalloy GH4133's fatigue behavior than that with zero mean strains.

  11. 77 FR 76842 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Science.gov (United States)

    2012-12-31

    ... Aircraft Gas Turbine Engines and Identification Plate for Aircraft Engines AGENCY: Federal Aviation... Environmental Protection Agency (EPA) proposed new aircraft engine emission standards for oxides of nitrogen (NO... turbojet engines with rated thrusts greater than 26.7 kilonewtons (kN) (76 FR 45012, July 27, 2011)....

  12. 78 FR 63015 - 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... aircraft engines which, in the EPA Administrator's judgment, causes or contributes to air pollution that... aircraft engine emission standards for oxides of nitrogen (NO X ), compliance flexibilities, and...

  13. 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... emission of any air pollutant from classes of aircraft engines which, in the EPA Administrator's judgment... standards. On July 27, 2011, the EPA proposed new aircraft engine emission standards for oxides of...

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

    Science.gov (United States)

    2010-07-01

    ... water consumption, high-water level when the system sprays excess water, and low-water level when the... allowable liquid fuel rate and governed speed with 0.5 ±0.1 percent, by volume, of natural gas in the intake... cooling water shall be filled with the quantity of water recommended by the applicant. No cooling...

  15. Electrochemical high-temperature gas sensors

    Science.gov (United States)

    Saruhan, B.; Stranzenbach, M.; Yüce, A.; Gönüllü, Y.

    2012-06-01

    Combustion produced common air pollutant, NOx associates with greenhouse effects. Its high temperature detection is essential for protection of nature. Component-integration capable high-temperature sensors enable the control of combustion products. The requirements are quantitative detection of total NOx and high selectivity at temperatures above 500°C. This study reports various approaches to detect NO and NO2 selectively under lean and humid conditions at temperatures from 300°C to 800°C. All tested electrochemical sensors were fabricated in planar design to enable componentintegration. We suggest first an impedance-metric gas sensor for total NOx-detection consisting of NiO- or NiCr2O4-SE and PYSZ-electrolyte. The electrolyte-layer is about 200μm thickness and constructed of quasi-single crystalline columns. The sensing-electrode (SE) is magnetron sputtered thin-layers of NiO or NiCr2O4. Sensor sensitivity for detection of total NOx has been measured by applying impedance analysis. The cross-sensitivity to other emission gases such as CO, CO2, CH4 and oxygen (5 vol.%) has been determined under 0-1000ppm NO. Sensor maintains its high sensitivity at temperatures up to 550°C and 600°C, depending on the sensing-electrode. NiO-SE yields better selectivity to NO in the presence of oxygen and have shorter response times comparing to NiCr2O4-SE. For higher temperature NO2-sensing capability, a resistive DC-sensor having Al-doped TiO2-sensing layers has been employed. Sensor-sensitivity towards NO2 and cross-sensitivity to CO has been determined in the presence of H2O at temperatures 600°C and 800°C. NO2 concentrations varying from 25 to 100ppm and CO concentrations from 25 to 75ppm can be detected. By nano-tubular structuring of TiO2, NO2 sensitivity of the sensor was increased.

  16. 废气涡轮增压器故障诊断浅谈%Fault Diagnosis of Exhaust Gas Turbochargers

    Institute of Scientific and Technical Information of China (English)

    谷伟

    2014-01-01

    废气涡轮增压器被广泛应用于采油平台发电机组中。描述了废气涡轮增压器的构造、原理及作用,提出采用正确的使用和保养方法。针对影响增压器使用寿命因素加以诊断分析,并说明使用中的注意事项,意在减少增压器故障,延长其使用寿命,降低维护费用。%Exhaust gas turbochargers are widely applied in the generator sets of oil platforms. In the paper,the struc-ture,principle and functions of gas turbochargers were described and proper usage and maintenance methods were proposed. Moreover,factors affecting the service life of the turbochargers were diagnosed and analyzed and precau-tions were explained,aiming to reduce turbocharger failures,prolong their service life and reduce maintenance costs.

  17. 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.

  18. Experimental Investigation of a Temperature-Controlled Car Seat Powered by an Exhaust Thermoelectric Generator

    Science.gov (United States)

    Du, H.; Wang, Y. P.; Yuan, X. H.; Deng, Y. D.; Su, C. Q.

    2016-03-01

    To improve the riding comfort and rational utilization of the electrical energy captured by an automotive thermoelectric generator (ATEG), a temperature-controlled car seat was constructed to adjust the temperature of the car seat surface. Powered by the ATEG and the battery, the seat-embedded air conditioner can improve the riding comfort using a thermoelectric device to adjust the surface temperature of the seat, with an air duct to regulate the cold side and hot side of the thermoelectric device. The performance of the thermoelectric cooler (TEC) and theoretical analysis on the optimum state of the TEC device are put forward. To verify the rationality of the air duct design and to ensure sufficient air supply, the velocity field of the air duct system was obtained by means of the finite element method. To validate the reliability of the numerical simulation, the air velocity around the thermoelectric device was measured by a wind speed transmitter. The performance of the temperature-controlled car seat has been validated and is in good agreement with bench tests and real vehicle tests.

  19. The Study of Automotive Exhaust Gas Turbine Power Generation Technology%汽车废气涡轮发电技术的研究

    Institute of Scientific and Technical Information of China (English)

    张勇斌

    2015-01-01

    汽车废气涡轮发电是利用汽车尾气能量推动涡轮转动并带动发电机发电的一项技术。基于汽车节能的思想,以东风EQ6100型内燃机为例设计了汽车废气回收利用装置,并从内燃机进气流量入手配合实际循环状态和排气状况,对热量的回收效益和涡轮机功率进行了计算,并对涡轮机结构进行了初步设计,发电机进行了选型匹配。计算得出了汽车废气涡轮发电涡轮机的功率和排气能量大小,证实了利用汽车废气驱动涡轮发电的可行性。%Automotive exhaust gas turbine power generation is a technology to use the car exhaust energy to rotate and drive a turbine generator to generate electricity. Based on the idea of energy-saving cars, taking Dongfeng EQ6100-type internal combustion engine as an example, a vehicle exhaust recycling system was designed. Combining the engine intake air flow rate and the actual cycling situation as well as the exhaust situation, the heat recovery efficiency and turbine power were calculated, turbine structure was preliminarily designed, and the selection of matching generators was carried out. Calculation of the automobile exhaust turbine generator turbine power and exhaust energy confirmed the feasibility of the use of motor vehicle exhaust to drive a turbine to generate electricity.

  20. Gas formation. Formation temperatures of thermogenic and biogenic methane.

    Science.gov (United States)

    Stolper, D A; Lawson, M; Davis, C L; Ferreira, A A; Santos Neto, E V; Ellis, G S; Lewan, M D; Martini, A M; Tang, Y; Schoell, M; Sessions, A L; Eiler, J M

    2014-06-27

    Methane is an important greenhouse gas and energy resource generated dominantly by methanogens at low temperatures and through the breakdown of organic molecules at high temperatures. However, methane-formation temperatures in nature are often poorly constrained. We measured formation temperatures of thermogenic and biogenic methane using a "clumped isotope" technique. Thermogenic gases yield formation temperatures between 157° and 221°C, within the nominal gas window, and biogenic gases yield formation temperatures consistent with their comparatively lower-temperature formational environments (<50°C). In systems where gases have migrated and other proxies for gas-generation temperature yield ambiguous results, methane clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models. PMID:24970083

  1. In situ gas temperature measurements by UV-absorption spectroscopy

    DEFF Research Database (Denmark)

    Fateev, Alexander; Clausen, Sønnik

    2009-01-01

    The absorption spectrum of the NO A(2)Sigma(+) <- X(2)Pi gamma-system can be used for in situ evaluation of gas temperature. Experiments were performed with a newly developed atmospheric-pressure high-temperature flow gas cell at highly uniform and stable gas temperatures over a 0.533 m path in t....... The accuracy of both methods is discussed. Validation of the classical Lambert-Beer law has been demonstrated at NO concentrations up to 500 ppm and gas temperatures up to 1,500 degrees C over an optical absorption path length of 0.533 m....

  2. ENVIRONMENTAL CHARACTERISTICS OF DIESEL ENGINE WITH UTILIZING EXHAUST GASES RECIRCULATION

    Directory of Open Access Journals (Sweden)

    Petar Kazakov

    2016-07-01

    Full Text Available From the various methods for reducing harmful exhaust emissions as combustion control, improved fuel injection form of the combustion chamber, recirculation of the combustion products, impact of smoke particles, the addition of water, synthetic fuel. Is established that the system for recirculation of exhaust gas is one of the most effective methods for obtaining of lower values of NOx, because the reduced temperature of the combustion process and excess oxygen.

  3. 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.

  4. High-Performance Silicon-Germanium-Based Thermoelectric Modules for Gas Exhaust Energy Scavenging

    Science.gov (United States)

    Romanjek, K.; Vesin, S.; Aixala, L.; Baffie, T.; Bernard-Granger, G.; Dufourcq, J.

    2015-06-01

    Some of the energy used in transportation and industry is lost as heat, often at high-temperatures, during conversion processes. Thermoelectricity enables direct conversion of heat into electricity, and is an alternative to the waste-heat-recovery technology currently used, for example turbines and other types of thermodynamic cycling. The performance of thermoelectric (TE) materials and modules has improved continuously in recent decades. In the high-temperature range ( T hot side > 500°C), silicon-germanium (SiGe) alloys are among the best TE materials reported in the literature. These materials are based on non-toxic elements. The Thermoelectrics Laboratory at CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives) has synthesized n and p-type SiGe pellets, manufactured TE modules, and integrated these into thermoelectric generators (TEG) which were tested on a dedicated bench with hot air as the source of heat. SiGe TE samples of diameter 60 mm were created by spark-plasma sintering. For n-type SiGe doped with phosphorus the peak thermoelectric figure of merit reached ZT = 1.0 at 700°C whereas for p-type SiGe doped with boron the peak was ZT = 0.75 at 700°C. Thus, state-of-the-art conversion efficiency was obtained while also achieving higher production throughput capacity than for competing processes. A standard deviation output reaching 1.9 ± 0.2 W for a 370 degree temperature difference. When the temperature difference was increased to 500°C, electrical power output increased to >3.6 W. An air-water heat exchanger was developed and 30 TE modules were clamped and connected electrically. The TEG was tested under vacuum on a hot-air test bench. The measured output power was 45 W for an air flow of 16 g/s at 750°C. The hot surface of the TE module reached 550°C under these conditions. Silicon-germanium TE modules can survive such temperatures, in contrast with commercial modules based on bismuth telluride, which are limited to 400°C.

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

    Science.gov (United States)

    Gutfrind, Christophe; Dufour, Laurent; Liebart, Vincent; Vannier, Jean-Claude; Vidal, Pierre

    2016-01-01

    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. PMID:27213398

  6. Effects of Exhaust Gas Recirculation on the Homogeneous Charge Combustion Process of n-Heptane at Different Load Conditions

    Institute of Scientific and Technical Information of China (English)

    LIU Dexin; FENG Hongqing; ZHENG Jincai; MILLER David L; CERNANSKY Nicholas P

    2005-01-01

    Effects of exhaust gas recirculation (EGR) on homogeneous charge combustion of n-heptane was studied through simulation and experiment. Experiments were carried out in a single cylinder, four-stroke, air cooled engine and a single cylinder, two-stroke, water cooled engine. In the four-stroke engine, experiments of the effects of EGR were examined using heated N2 addition as a surrogate for external EGR and modifying engine to increase internal EGR. The ignition timing was sensitive to EGR due to thermal and chemical effects. EGR or extra air is a key factor in eliminating knock during mid-load conditions. For higher load operation the only way to avoid knock is to control reaction timing through the use of spark ignition. Experimental and modeling results from the two-stroke engine show that auto-ignition can be avoided by increasing the engine speed. The two-stroke engine experiments indicate that high levels of internal EGR can enable spark ignition at lean conditions. At higher load conditions, increasing the engine speed is an effective method to control transition from homogeneous charge compression ignition (HCCI) operation to non-HCCI operation and successful spark ignition of a highly dilute mixture can avoid serious knock.

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

    Science.gov (United States)

    Gutfrind, Christophe; Dufour, Laurent; Liebart, Vincent; Vannier, Jean-Claude; Vidal, Pierre

    2016-05-20

    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.

  8. Toward gas exhaustion in the W51 high-mass protoclusters

    CERN Document Server

    Ginsburg, Adam; Goddi, Ciriaco; Galván-Madrid, Roberto; Dale, James E; Bally, John; Battersby, Cara D; Youngblood, Allison; Sankrit, Ravi; Smith, Rowan; Darling, Jeremy; Kruijssen, J M Diederik; Liu, Hauyu Baobab

    2016-01-01

    We present new JVLA observations of the high-mass cluster-forming region W51A from 2 to 16 GHz with resolution ${\\theta}_{fwhm} \\approx$ 0.3 - 0.5". The data reveal a wealth of observational results: (1) Currently-forming, very massive (proto-O) stars are traced by o-H2CO $2_{1,1}-2_{1,2}$ emission, suggesting that this line can be used efficiently as a massive protostar tracer. (2) There is a spatially distributed population of $\\sim$mJy continuum sources, including hypercompact H ii regions and candidate colliding wind binaries, in and around the W51 proto-clusters. (3) There are two clearly detected protoclusters, W51e and W51 IRS2, that are gas-rich but may have most of their mass in stars within their inner $\\sim$ 0.05 pc. The majority of the bolometric luminosity in W51 most likely comes from a third population of OB stars between these clusters. The presence of a substantial population of exposed O-stars coincident with a population of still-forming massive stars, along with a direct measurement of the...

  9. Measured gas and particle temperatures in VTT's entrained flow reactor

    DEFF Research Database (Denmark)

    Clausen, Sønnik; Sørensen, L.H.

    2006-01-01

    Particle and gas temperature measurements were carried out in experiments on VTTs entrained flow reactor with 5% and 10% oxygen using Fourier transform infrared emission spectroscopy (FTIR). Particle temperature measurements were performed on polish coal,bark, wood, straw particles, and bark...... and wood particles treated with additive. A two-color technique with subtraction of the background light was used to estimate particle temperatures during experiments. A transmission-emission technique was used tomeasure the gas temperature in the reactor tube. Gas temperature measurements were in good...

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

    DEFF Research Database (Denmark)

    Stolberg-Rohr, Thomine Kirstine

    for the first time. Information about CO2 absorption and emission in combustion conditions is highly demanded for accurate modelling of heat transfer processes during combustion in large ship engines which in turn is crucial for understanding the formation of emission gasses, in particular NOx.......D study investigates a possible solution to this problem, which is to balance out the signal contribution from water vapour by means of carefully designed and manufactured optical bandpass filters. The thesis, presents a thorough theoretical description of the NDIR sensor concept together with simulations...... filters in general, and temperature invariant filters in particular. This work has led to the derivation of the thermo-optical expansion coefficients of embedded PbTe and ZnSe thin films, frequently used in optical bandpass filters for the mid-infrared range. Knowledge of these coefficients allows...

  11. Hydrogen production from biomass pyrolysis gas via high temperature steam reforming process

    International Nuclear Information System (INIS)

    Full text: The aim of this work has been undertaken as part of the design of continuous hydrogen production using the high temperature steam reforming process. The steady-state test condition was carried out using syngas from biomass pyrolysis, whilst operating at high temperatures between 600 and 1200 degree Celsius. The main reformer operating parameters (e.g. temperature, resident time and steam to biomass ratio (S/B)) have been examined in order to optimize the performance of the reformer. The operating temperature is a key factor in determining the extent to which hydrogen production is increased at higher temperatures (900 -1200 degree Celsius) whilst maintaining the same as resident time and S/B ratio. The effects of exhaust gas composition on heating value were also investigated. The steam reforming process produced methane (CH4) and ethylene (C2H4) between 600 to 800 degree Celsius and enhanced production ethane (C2H6) at 700 degree Celsius. However carbon monoxide (CO) emission was slightly increased for higher temperatures all conditions. The results show that the use of biomass pyrolysis gas can produce higher hydrogen production from high temperature steam reforming. In addition the increasing reformer efficiency needs to be optimized for different operating conditions. (author)

  12. Modelling of an SCR catalytic converter for diesel exhaust after treatment: Dynamic effects at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Tronconi, Enrico; Nova, Isabella; Ciardelli, Cristian [Dipartimento di Chimica, Materiali e Ingegneria Chimica ' G. Natta' , Politecnico di Milano, P.zza L. Da Vinci 32, 20133 Milano (Italy); Chatterjee, Daniel; Bandl-Konrad, Brigitte; Burkhardt, Thomas [DaimlerChrysler AG Abteilung RBP/C, HPC: 096-E220, D-70546 Stuttgart (Germany)

    2005-08-15

    As part of a fundamental and applied work on the development of an unsteady mathematical model of the NH{sub 3}-selective catalytic reduction (SCR) process for design and control of integrated after-treatment systems of heavy-duty engines, we present herein a transient kinetic analysis of the standard SCR NO+NH{sub 3} system which provides new insight in the catalytic kinetics and mechanism prevailing at low temperatures. Based on kinetic runs performed over a commercial powdered V{sub 2}O{sub 5}-WO{sub 3}-TiO{sub 2} catalyst in the 175-450{sup o}C T-range feeding NH{sub 3} and NO (1000ppm) in the presence of H{sub 2}O (1-10%, v/v) and O{sub 2} (2-6%, v/v), an original dual-site modified redox rate law is derived which effectively accounts for NH{sub 3} inhibition effects observed during transient reactive experiments at T<250{sup o}C. We also demonstrate that implementation of the novel modified redox kinetics into a fully predictive 1D+1D model of SCR monolith reactors can significantly improve simulations of SCR transient runs at different scales, including engine test bench experiments over full-scale SCR honeycomb catalysts.

  13. Deactivation of Pd Catalysts by Water during Low Temperature Methane Oxidation Relevant to Natural Gas Vehicle Converters

    Directory of Open Access Journals (Sweden)

    Rahman Gholami

    2015-03-01

    Full Text Available Effects of H2O on the activity and deactivation of Pd catalysts used for the oxidation of unburned CH4 present in the exhaust gas of natural-gas vehicles (NGVs are reviewed. CH4 oxidation in a catalytic converter is limited by low exhaust gas temperatures (500–550 °C and low concentrations of CH4 (400–1500 ppmv that must be reacted in the presence of large quantities of H2O (10–15% and CO2 (15%, under transient exhaust gas flows, temperatures, and compositions. Although Pd catalysts have the highest known activity for CH4 oxidation, water-induced sintering and reaction inhibition by H2O deactivate these catalysts. Recent studies have shown the reversible inhibition by H2O adsorption causes a significant drop in catalyst activity at lower reaction temperatures (below 450 °C, but its effect decreases (water adsorption becomes more reversible with increasing reaction temperature. Thus above 500 °C H2O inhibition is negligible, while Pd sintering and occlusion by support species become more important. H2O inhibition is postulated to occur by either formation of relatively stable Pd(OH2 and/or partial blocking by OH groups of the O exchange between the support and Pd active sites thereby suppressing catalytic activity. Evidence from FTIR and isotopic labeling favors the latter route. Pd catalyst design, including incorporation of a second noble metal (Rh or Pt and supports high O mobility (e.g., CeO2 are known to improve catalyst activity and stability. Kinetic studies of CH4 oxidation at conditions relevant to natural gas vehicles have quantified the thermodynamics and kinetics of competitive H2O adsorption and Pd(OH2 formation, but none have addressed effects of H2O on O mobility.

  14. Effect of nozzle hole size coupling with exhaust gas re-circulation on the engine emission perfomance based on KH-ACT spray model

    OpenAIRE

    Zhang Liang; He Zhixia; Wang Qian; Guo Genmiao

    2015-01-01

    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 experimen...

  15. 废气涡轮增压器的优缺点分析%Analysis of the advantages and disadvantages for exhaust gas turbocharger

    Institute of Scientific and Technical Information of China (English)

    富刚

    2013-01-01

    The exhaust gas turbocharger is a new technology for engine and a good solution for poor condition of nat-urally aspirated engine. Therefore, the exhaust gas turbocharger has been widely applied in a variety of models, particularly in sedan; Of course, the exhaust gas turbocharger also has its own drawbacks, so people use many effective ways to im-prove and compensate its shortcomings.%  废气涡轮增压器作为发动机的一项新技术,很好解决了自然吸气发动机动力性不佳的问题。因此,废气涡轮增压器在各种车型特别是轿车上得到了广泛的应用;当然,废气涡轮增压器也有其自身的缺点,因此针对其缺点人们采取了许多的有效的改善方法来弥补其缺陷。

  16. 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.)

  17. Tokamak fusion reactor exhaust

    International Nuclear Information System (INIS)

    This report presents a compilation of papers dealing with reactor exhaust which were produced as part of the TIGER Tokamak Installation for Generating Electricity study at Culham. The papers are entitled: (1) Exhaust impurity control and refuelling. (2) Consideration of the physical problems of a self-consistent exhaust and divertor system for a long burn Tokamak. (3) Possible bundle divertors for INTOR and TIGER. (4) Consideration of various magnetic divertor configurations for INTOR and TIGER. (5) A appraisal of divertor experiments. (6) Hybrid divertors on INTOR. (7) Refuelling and the scrape-off layer of INTOR. (8) Simple modelling of the scrape-off layer. (9) Power flow in the scrape-off layer. (10) A model of particle transport within the scrape-off plasma and divertor. (11) Controlled recirculation of exhaust gas from the divertor into the scrape-off plasma. (U.K.)

  18. Experimental study on scale prevention method using exhausted gases from geothermal power station. Chinetsu hatsudensho no haishutsu gas wo mochiita scale fuchaku boshiho no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Hirowatari, K. (Kyushu Electric Power Co. Ltd., Fukuoka (Japan))

    1990-10-25

    This paper reports on a method of suppressing the scale deposition, which is considered to be promising in view of both economical efficiency of power generation and prevention of environmental pollution. A brief summary is first given of the well known fact that the silica scaling can be suppressed by keeping geothermal water in acidic conditions. There is next a description of an experiment, which was performed at the Hatchobaru geothermal power station, on the control of pH condition of geothermal water using a technique of bringing it in contact with exhaust gas discharged from the plant, which contains 70% of CO {sub 2} gas and about 2% of H {sub 2} S gas in volume. It is shown by this experiment that pH of the geothermal water was lowered to a value less than about 5.5 and thereby the rate of scale deposition could be reduced to about one twentieth of that observed in the case of original thermal water. Furthermore, it is noted that H {sub 2} S gas causes the deposition of much slime containing various kinds of metal elements on the filler of vessels used for pH adjustment of the geothermal water, but it can be efficiently removed from the exhaust gas by means of the pressure swing adsorption process. 8 refs., 15 figs., 4 tabs.

  19. Tailoring the structural and microstructural properties of nanosized tantalum oxide for high temperature electrochemical gas sensors.

    Science.gov (United States)

    Bonavita, Anna; Di Bartolomeo, Elisabetta; Chevallier, Laure; D'Ottavi, Cadia; Licoccia, Silvia; Traversa, Enrico

    2009-07-01

    Ta2O5 nanopowders to be used as sensing electrodes in high temperature electrochemical gas sensors for hydrocarbons detection were synthesized using a sol-gel method and their structural and microstructural properties were investigated. The as-synthesized powders were heated at different temperatures in the range 250-1000 degrees C and characterized by TG-DTA, XRD, SEM, TEM and FT-IR. This investigation allowed to identify the correct thermal treatments to achieve the microstructural, textural and functional stability of materials working at high temperature, preserving their nano-metric grain size. Planar sensors fabricated by using Ta2O5 powders treated at 750 degrees C showed promising results for the selective detection of propylene at high temperature (700 degrees C). The good stability of the sensing response after gas exposure at high temperature was correlated to the stable microstructure the electrodes. Thus, Ta2O5 powders seems good candidate as sensing electrode for sensors for automotive exhausts monitoring. PMID:19916469

  20. Novel silica membranes for high temperature gas separations

    KAUST Repository

    Bighane, Neha

    2011-04-01

    This article describes fabrication of novel silica membranes derived via controlled oxidative thermolysis of polydimethylsiloxane and their gas separation performance. The optimized protocol for fabrication of the silica membranes is described and pure gas separation performance in the temperature range 35-80°C is presented. It is observed that the membranes exhibit activated transport for small gas penetrants such as He, H 2 and CO 2. The membranes can withstand temperatures up to 350°C in air and may ultimately find use in H 2/CO 2 separations to improve efficiency in the water-gas shift reactor process. © 2011 Elsevier B.V.

  1. Temperature detection in a gas turbine

    Science.gov (United States)

    Lacy, Benjamin; Kraemer, Gilbert; Stevenson, Christian

    2012-12-18

    A temperature detector includes a first metal and a second metal different from the first metal. The first metal includes a plurality of wires and the second metal includes a wire. The plurality of wires of the first metal are connected to the wire of the second metal in parallel junctions. Another temperature detector includes a plurality of resistance temperature detectors. The plurality of resistance temperature detectors are connected at a plurality of junctions. A method of detecting a temperature change of a component of a turbine includes providing a temperature detector include ing a first metal and a second metal different from the first metal connected to each other at a plurality of junctions in contact with the component; and detecting any voltage change at any junction.

  2. Soft Sensor Model of Automotive Exhaust Gas Oxygen Sensor%汽车废气氧传感器软测量模型

    Institute of Scientific and Technical Information of China (English)

    黄彩虹; 金福江

    2013-01-01

    The model of automotive exhaust gas oxygen sensor is one of the key technologies in the engine air-fuel ratio control system.There exists some deficiencies of the traditional relay model.Adopting a modeling method with tests,a soft sensor model was built between excessive air coefficient,temperature and output voltage.Rough estimation of the parameters were conducted with three-sum methods,and the optimum parameters were found by particle swarm optimization algorithm (PSO).And the verification of the model was showed with experimental data.The simulation results show that the model of the sensor has the advantage of simple structure and higher predictive accuracy.It can be used in simulation research of the engine air-fuel ratio control system.%汽车废气氧(EGO)传感器模型是实现发动机空燃比闭环控制的关键技术之一.传统采用的继电器模型,存在一定的不足.采用实验建模的方法,建立了过量空气系数、温度与输出电压之间的软测量模型.利用三段和法对模型参数进行初步估计,得到参数的粗略值,然后利用粒子群优化算法,寻找最优参数,并对所得结果进行检验.仿真结果表明:该软测量模型结构简单,预测精度高,可以用于空燃比闭环控制系统的仿真研究.

  3. Photochemical transformation of aircraft exhausts at their transition from the plume to the large scale dispersion in the Northern temperature belt

    Energy Technology Data Exchange (ETDEWEB)

    Karol, I.L.; Kiselev, A.A. [Main Geophysical Observatory, St.Petersburg (Russian Federation)

    1997-12-31

    The 2-D diurnally varying photochemical model of the Northern temperate zonal tropospheric belt with fixed (off line) temperature and air transport is used for the description of the formation of aircraft exhaust concentration distribution in the North Atlantic commercial flight corridor, based on actual flights in summer and winter. A strong diurnal and seasonal variation of emitted NO{sub x} oxidation rate is revealed and evaluated. (author) 11 refs.

  4. Temperature effect on gas phase alkylbenzene dealkylation

    International Nuclear Information System (INIS)

    Dealkylation of ethylbenzene, propylbenzene, and isopropylbenzene by radiolytically formed 2H3+ ions has been studied in the gaseous phase as a function of the irradiation temperature. The extent of the reaction, which increases with the temperature follows the order ethylbenzene -1 between the activation energies for dealkylation of ethylbenzene and isopropylbenzene, and of ethylbenzene and propylbenzene, respectively. (author)

  5. 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. PMID:27091946

  6. 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.

  7. Seismic stability of VGM type high temperature gas cooled reactors

    International Nuclear Information System (INIS)

    The main principles of the design provision of high temperature gas cooled VGM reactors seismic stability and the results of calculations, performed by linear-spectral method are presented. (author). 1 ref., 10 figs

  8. Reflection error correction of gas turbine blade temperature

    Science.gov (United States)

    Kipngetich, Ketui Daniel; Feng, Chi; Gao, Shan

    2016-03-01

    Accurate measurement of gas turbine blades' temperature is one of the greatest challenges encountered in gas turbine temperature measurements. Within an enclosed gas turbine environment with surfaces of varying temperature and low emissivities, a new challenge is introduced into the use of radiation thermometers due to the problem of reflection error. A method for correcting this error has been proposed and demonstrated in this work through computer simulation and experiment. The method assumed that emissivities of all surfaces exchanging thermal radiation are known. Simulations were carried out considering targets with low and high emissivities of 0.3 and 0.8 respectively while experimental measurements were carried out on blades with emissivity of 0.76. Simulated results showed possibility of achieving error less than 1% while experimental result corrected the error to 1.1%. It was thus concluded that the method is appropriate for correcting reflection error commonly encountered in temperature measurement of gas turbine blades.

  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

    2012-01-01

    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

  10. 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

  11. The Influence of Mixing in High Temperature Gas Phase Reactions

    DEFF Research Database (Denmark)

    Østberg, Martin

    1996-01-01

    The objective of this thesis is to describe the mixing in high temperature gas phase reactions.The Selective Non-Catalytic Reduction of NOx (referred as the SNR process) using NH3 as reductant was chosen as reaction system. This in-furnace denitrification process is made at around 1200 - 1300 K...... of the mixing in the SNR process using injection of NH3 with carrier gas into the flue gas in crossflow by a quartz nozzle.Experiments were made with variation in NH3 flow, carrier gas flow, carrier gas composition (O2 concentration) and reactor temperature. Natural gas has been used as an addition...... concentrations in the injected gas between 0 - 20 vol%.Using a nozzle with a diameter of 1.9 mm the reduction of NO is dependent on the carrier gas flow for temperatures above 1200 K (1100 K when natural gas is added).It is shown that this effect can not be described by macromixing using a simple reactor model...

  12. Swirl and blade wakes in the interaction between gas turbines and exhaust diffusers investigated by endoscopic particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Opilat, Victor

    2011-10-21

    Exhaust diffusers studied in this thesis are installed behind the last turbine stage of gas turbines, including those used in combined cycle power plants. Extensive research made in recent years proved that effects caused by an upstream turbine need to be taken into account when designing efficient diffusers. Under certain conditions these effects can stabilize the boundary layer in diffusers and prevent separation. In this research the impact of multiple parameters, such as tip leakage flow, swirl, and rotating blade wakes, on the performance of a diffuser is studied. Experiments were conducted using a diffuser test rig with a rotating bladed wheel as a turbine effect generator and with an additional tip leakage flow insert. The major advantages of this test rig are modularity and easy variation of the main parameters. To capture the complexity and understand the physics of diffuser flow, and to clarify the phenomenon of the flow stabilisation, the 2D endoscopic laser optical measurement technique Partide Image Velocimetry (PIV) was adopted to the closed ''rotating'' diffuser test rig. Intensity and distribution of vortices in the blade tip area are decisive for diffuser performance. Large vortices in the annular diffuser inlet behind the blade tips interact with the boundary layer in diffusers. At design point these vortices are very early suppressed by the main flow. For the operating point with a low value of the flow coefficient (negative swirl), vortices are ab out two tim es stronger than for design point and the boundary layer is destabilized. V mtices develop in the direction contrary to swirl in the main flow and just cause flow destabilization. Coherent back flow zones are induced and reduction of diffuser performance occurs. For the operating point with positive swirl (for a high flow coefficient value), these vortices are also strong but do not counteract the main flow because they develop in the same direction with the swirl in the

  13. GC/MS Gas Separator Operates At Lower Temperatures

    Science.gov (United States)

    Sinha, Mahadeva P.; Gutnikov, George

    1991-01-01

    Experiments show palladium/silver tube used to separate hydrogen carrier gas from gases being analyzed in gas-chromatography/mass-spectrometry (GC/MS) system functions satisfactorily at temperatures as low as 70 to 100 degrees C. Less power consumed, and catalytic hydrogenation of compounds being analyzed diminished. Because separation efficiency high even at lower temperatures, gas load on vacuum pump of mass spectrometer kept low, permitting use of smaller pump. These features facilitate development of relatively small, lightweight, portable GC/MS system for such uses as measuring concentrations of pollutants in field.

  14. Investigation and evaluation of potential exhaust braking strategiesusing model predictive control

    OpenAIRE

    Hallqvist, Erik

    2015-01-01

    The eciency of today's aftertreatment system relies on the exhaust gas temperature.The Selective Catalytic Reduction system, which is a part of theaftertreatment system has an operating temperature window which starts atapproximately 200C in order to work as eciently as possible. Rolling downhillwithout burning fuel could cause the exhaust aftertreatment system to cooldown below this window, which gives higher emissions when burning fuel again.This thesis focuses on investigating the potentia...

  15. A Smart Gas Sensor Insensitive to Humidity and Temperature Variations

    Energy Technology Data Exchange (ETDEWEB)

    Hajmirzaheydarali, Mohammadreza; Ghafarinia, Vahid, E-mail: m.heydarali@ee.kntu.ac.ir, E-mail: ghafarinia@ee.kntu.ac.ir [Electronic Materials Laboratory, Electronic Engineering Department, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

    2011-02-15

    The accuracy of the quantitative sensing of volatile organic compounds by chemoresistive gas sensors suffers from the fluctuations in the background atmospheric conditions. This is caused by the drift-like terms introduced in the responses by these instabilities, which should be identified and compensated. Here, a mathematical model is presented for a specific chemoresistive gas sensor, which facilitates these identification and compensation processes. The resistive gas sensor was considered as a multi-input-single-output system. Along with the steady state value of the measured sensor resistance, the ambient humidity and temperature are the inputs to the system, while the concentration level of the target gas is the output. The parameters of the model were calculated based on the experimental database. The model was simulated by the utilization of an artificial neural network. This was connected to the sensor and could deliver the correct contamination level upon receiving the measured gas response, ambient humidity and temperature.

  16. EFFECTS OF GAS TYPE AND TEMPERATURE ON FINE PARTICLE FLUIDIZATION

    Institute of Scientific and Technical Information of China (English)

    Chunbao Xu; J.-X. Zhu

    2006-01-01

    The influence of gas type (helium and argon) and bed temperature (77-473 K) on the fluidization behaviour of Geldart groups C and A particles was investigated. For both types of particles tested, i.e., Al2O3 (4.8 μm) and glass beads (39 μm), the fluidization quality in different gases shows the following priority sequence: Ar>He. In the same gaseous atmosphere, the particles when fluidized at an elevated temperature usually show larger bed voidages, higher bed pressure drops, and a lower umf for the group A powder, all indicating an enhancement in fluidization quality. Possible mechanisms governing the operations of gas type and temperature in influencing the fluidization behaviours of fine particles have been discussed with respect to the changes in both gas properties and interparticle forces (on the basis of the London-van der Waals theory). Gas viscosity (varying significantly with gas-type and temperature) proves to be the key parameter that influences the bed pressure drops and umf in fluidization of fine particles, while the interparticle forces (also varying with gas-type and temperature) may play an important role in fine-particle fluidization by affecting the expansion behaviour of the particle-bed.

  17. Control rod drive for high temperature gas cooled reactor

    Institute of Scientific and Technical Information of China (English)

    DengJun-Xian; XuJi-Ming; 等

    1998-01-01

    This control rod drive is developed for HTR-10 high temperature gas cooled test reactor.The stepmotor is prefered to improve positioning of the control rod and the scram behavior.The preliminary test in 1600170 ambient temperature shows that the selected stepmotor and transmission system can meet the main operation function requirements of HTR-10.

  18. Study on Temperature Modulation Techniques for Micro Gas Sensors

    Institute of Scientific and Technical Information of China (English)

    Guangfen Wei; Zhenan Tang; Hongquan Zhang; Yanbing Xue; Jun Yu

    2006-01-01

    The sensitivity and selectivity of gas sensors are related with not only sensing material, but also their operating temperatures. Applying this property, temperature modulation technique has been proposed to improve the selectivity of gas sensors. With a newly developed alumina based micro gas sensor, the sensitivity to CO and CH4 at different operating temperatures was investigated. By modulating the temperature of the sensor at pulse and sine wave modes with different frequencies and amplitudes, the dynamic responses of the sensor were measured and processed. Results show that the modulating waveshape plays an important role in the improvement of selectivity, while the influence of frequency is small at the suitable sampling frequency in the range of 25 mHz~200 mHz.

  19. Modern gas-based temperature and pressure measurements

    CERN Document Server

    Pavese, Franco

    2013-01-01

    This 2nd edition volume of Modern Gas-Based Temperature and Pressure Measurements follows the first publication in 1992. It collects a much larger set of information, reference data, and bibliography in temperature and pressure metrology of gaseous substances, including the physical-chemical issues related to gaseous substances. The book provides solutions to practical applications where gases are used in different thermodynamic conditions. Modern Gas-Based Temperature and Pressure Measurements, 2nd edition is the only comprehensive survey of methods for pressure measurement in gaseous media used in the medium-to-low pressure range closely connected with thermometry. It assembles current information on thermometry and manometry that involve the use of gaseous substances which are likely to be valid methods for the future. As such, it is an important resource for the researcher. This edition is updated through the very latest scientific and technical developments of gas-based temperature and pressure measurem...

  20. Determination of gas temperature in the plasmatron channel according to the known distribution of electronic temperature

    Directory of Open Access Journals (Sweden)

    Gerasimov Alexander V.

    2013-01-01

    Full Text Available An analytical method to calculate the temperature distribution of heavy particles in the channel of the plasma torch on the known distribution of the electronic temperature has been proposed. The results can be useful for a number of model calculations in determining the most effective conditions of gas blowing through the plasma torch with the purpose of heating the heavy component. This approach allows us to understand full details about the heating of cold gas, inpouring the plasma, and to estimate correctly the distribution of the gas temperature inside the channel.

  1. Effects of Gas Velocity and Temperature on Nitric Oxide Conversion in Simulated Catalytic Converter

    OpenAIRE

    Sathaporn Chuepeng

    2012-01-01

    Problem statement: Gaseous emissions from gasoline engine such as carbon monoxide, unburned hydrocarbon and nitrogen oxides were usually reduced in three-way catalytic converter simultaneously around theoretical fuel and air combustion. Engine speed and load and other parameters were varied over a wide range of operating conditions, resulting in different exhaust gas composition and condition intake into catalytic converter. This work was studied the conversion of Nitric Oxide (NO) in exhaust...

  2. Controlling automotive exhaust emissions: successes and underlying science.

    Science.gov (United States)

    Twigg, Martyn V

    2005-04-15

    Photochemical reactions of vehicle exhaust pollutants were responsible for photochemical smog in many cities during the 1960s and 1970s. Engine improvements helped, but additional measures were needed to achieve legislated emissions levels. First oxidation catalysts lowered hydrocarbon and carbon monoxide, and later nitrogen oxides were reduced to nitrogen in a two-stage process. By the 1980s, exhaust gas could be kept stoichiometric and hydrocarbons, carbon monoxide and nitrogen oxides were simultaneously converted over a single 'three-way catalyst'. Today, advanced three-way catalyst systems emissions are exceptionally low. NOx control from lean-burn engines demands an additional approach because NO cannot be dissociated under lean conditions. Current lean-burn gasoline engine NOx control involves forming a nitrate phase and periodically enriching the exhaust to reduce it to nitrogen, and this is being modified for use on diesel engines. Selective catalytic reduction with ammonia is an alternative that can be very efficient, but it requires ammonia or a compound from which it can be obtained. Diesel engines produce particulate matter, and, because of health concerns, filtration processes are being introduced to control these emissions. On heavy duty diesel engines the exhaust gas temperature is high enough for NO in the exhaust to be oxidised over a catalyst to NO2 that smoothly oxidises particulate material (PM) in the filter. Passenger cars operate at lower temperatures, and it is necessary to periodically burn the PM in air at high temperatures.

  3. Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.

    Science.gov (United States)

    Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C

    2011-01-01

    The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns.

  4. High temperature gas dynamics an introduction for physicists and engineers

    CERN Document Server

    Bose, Tarit K

    2014-01-01

    High Temperature Gas Dynamics is a primer for scientists, engineers, and students who would like to have a basic understanding of the physics and the behavior of high-temperature gases. It is a valuable tool for astrophysicists as well. The first chapters treat the basic principles of quantum and statistical mechanics and how to derive thermophysical properties from them. Special topics are included that are rarely found in other textbooks, such as the thermophysical and transport properties of multi-temperature gases and a novel method to compute radiative transfer. Furthermore, collision processes between different particles are discussed. Separate chapters deal with the production of high-temperature gases and with electrical emission in plasmas, as well as related diagnostic techniques.This new edition adds over 100 pages and includes the following updates: several sections on radiative properties of high temperature gases and various radiation models, a section on shocks in magneto-gas-dynamics, a sectio...

  5. On The Gas Temperature of Molecular Cloud Cores

    CERN Document Server

    Juvela, M

    2011-01-01

    We investigate the uncertainties affecting the temperature profiles of dense cores of interstellar clouds. In regions shielded from external ultraviolet radiation, the problem is reduced to the balance between cosmic ray heating, line cooling, and the coupling between gas and dust. We show that variations in the gas phase abundances, the grain size distribution, and the velocity field can each change the predicted core temperatures by one or two degrees. We emphasize the role of non-local radiative transfer effects that often are not taken into account, for example, when modelling the core chemistry. These include the radiative coupling between regions of different temperature and the enhanced line cooling near the cloud surface. The uncertainty of the temperature profiles does not necessarily translate to a significant error in the column density derived from observations. However, depletion processes are very temperature sensitive and a two degree difference can mean that a given molecule no longer traces t...

  6. Gas-flow fluctuation velocity within exhaust tube of pulse-jet engine%脉冲发动机喷管内气流压力波动速度研究

    Institute of Scientific and Technical Information of China (English)

    许林云; 周宏平; 徐幼林

    2007-01-01

    A portable pulse fogger, in which the fog will be generated by inducing pesticide into the pulse-jet engine exhaust tube that is full of high temperature and high speed exhaust gas, can be applied in disease and insect controling in forestry, greenhouse and sanitation with the advantages of high application efficiency and low environmental pollution. A system for measuring the gas-flow fluctuation velocity was set up to obtain the pressure signals at different axial positions of exhaust tube. On the principle of correlation between pressure signals from one signal source, the correlation analysis of two pressure signals at various positions of exhaust tube had been carried out. The autocorrelation function chart showed that the pressure signals in the exhaust tube were characterized as the sinusoidal or the cosinoidal waves with a few of random signals. The average gas-flow fluctuation velocity was derived from mutual correlation analysis of two signals at two positions. The average maximal gas flow velocity obtained by this measuring system was 5883 m/s, which was 8.72 times as fast as local sonic velocity 669 m/s.%便携式烟雾机是利用脉动发动机产生的高温、高速燃气将农药雾化形成直径微小的颗粒,达到高效、环保防治林木病虫害的目的.该文建立了一套气流波动速度测试装置,利用等直径喷管中气流脉动流动特性,测定喷管不同轴向位置处的压力信号,利用同一压力信号源流过喷管不同轴向位置处,相互之间具有相关性的原理,将喷管不同位置处获得的压力信号进行相关分析.自相关分析结果表明喷管内压力信号具有典型正(余)弦信号特征,只是其中包含少许随机信号.通过互相关分析可获得喷管中两测点之间的平均压力波动速度,即气流纵波的波动速度.测试计算结果表明喷管内气流最大平均压力波动速度达5833 m/s,相当于本地音速669 m/s的8.72倍.

  7. Simultaneous conversion of nitrogen oxides and soot into nitrogen and carbon dioxide over iron containing oxide catalysts in diesel exhaust gas

    International Nuclear Information System (INIS)

    This paper deals with the simultaneous catalytic conversion of NOx and soot into N2 and CO2 in diesel exhaust gas. Several iron containing oxide catalysts were partially modified by the alkali metal potassium and were used for NOx-soot reaction in a model exhaust gas. Fe1.9K0.1O3 has shown highest catalytic performance for N2 formation in the so far investigated catalysts. Further studies have shown that Fe1.9K0.1O3 was deactivated in a substantial way after about 20 TPR experiments due to the agglomeration of the promoter potassium. Experiments carried out over the aged Fe1.9K0.1O3 catalyst have shown that NOx-soot reaction was suppressed at higher O2 concentration, since O2-soot conversion was kinetically favored. In contrast to that, the catalytic activity was increased in presence of NO2 and H2O. Mechanistic examinations suggest that (CO) intermediates, formed at the soot surface, are the reactive sites in the NOx-soot reaction. Higher catalytic performance in presence of NO2 could be explained by the enhanced formation of these (CO) species. Moreover, nitrate species formed at the catalyst surface might also play an important role in NOx-soot conversion

  8. 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.

  9. Gravitational collapse of a magnetized fermion gas with finite temperature

    CERN Document Server

    Gaspar, I Delgado; Sussman, Roberto A; Rey, A Ulacia

    2013-01-01

    We examine the dynamics of a self--gravitating magnetized electron gas at finite temperature near the collapsing singularity of a Bianchi-I spacetime. Considering a general and appropriate and physically motivated initial conditions, we transform Einstein--Maxwell field equations into a complete and self--consistent dynamical system amenable for numerical work. The resulting numerical solutions reveal the gas collapsing into both, isotropic ("point-like") and anisotropic ("cigar-like") singularities, depending on the initial intensity of the magnetic field. We provide a thorough study of the near collapse behavior and interplay of all relevant state and kinematic variables: temperature, expansion scalar, shear scalar, magnetic field, magnetization and energy density. A significant qualitative difference in the behavior of the gas emerges in the temperature range $\\hbox{T} sim10^{4}\\hbox{K}$ and $\\hbox{T}\\sim 10^{7}\\hbox{K}$.

  10. Gravitational collapse of a magnetized fermion gas with finite temperature

    Energy Technology Data Exchange (ETDEWEB)

    Delgado Gaspar, I. [Instituto de Geofisica y Astronomia (IGA), La Habana (Cuba); Perez Martinez, A. [Instituto de Cibernetica, Matematica y Fisica (ICIMAF), La Habana (Cuba); Sussman, Roberto A. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico (ICN-UNAM), Mexico (Mexico); Ulacia Rey, A. [Instituto de Cibernetica, Matematica y Fisica (ICIMAF), La Habana (Cuba); Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico (ICN-UNAM), Mexico (Mexico)

    2013-07-15

    We examine the dynamics of a self-gravitating magnetized fermion gas at finite temperature near the collapsing singularity of a Bianchi-I spacetime. Considering a general set of appropriate and physically motivated initial conditions, we transform Einstein-Maxwell field equations into a complete and self-consistent dynamical system amenable for numerical work. The resulting numerical solutions reveal the gas collapsing into both, isotropic (''point-like'') and anisotropic (''cigar-like''), singularities, depending on the initial intensity of the magnetic field. We provide a thorough study of the near collapse behavior and interplay of all relevant state and kinematic variables: temperature, expansion scalar, shear scalar, magnetic field, magnetization, and energy density. A significant qualitative difference in the behavior of the gas emerges in the temperature range T/m{sub f} {proportional_to} 10{sup -6} and T/m{sub f} {proportional_to} 10{sup -3}. (orig.)

  11. Temperature distribution and control in liquefied petroleum gas fluidized beds

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Ping Wu; Yanping Zhang; Jing Yang; Lige Tong

    2004-01-01

    Temperature distribution and control have been investigated in a liquefied petroleum gas (LPG) fluidized bed with hollow corundum spheres (A12O3) of 0.867-1.212 mm in diameter at moderately high temperatures (800-1100℃). Experiments were carried out for the air consumption coefficient α in the range of 0.3 to 1.0 and the fluidization number N in the range of 1.3 to 3.0. Particle properties, initial bed height, α and N all affect temperature distribution in the bed. Bed temperature can be adjusted about 200℃ by combined the adjusting of α and N.

  12. Ceramic membranes for gas separation at high temperatures. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C.J.

    1994-03-01

    Superior heat, wear, erosion, and corrosion resistance of ceramic materials have motivated the studies of processing-structure-performance interrelationships of ceramic membranes for high temperature gas separations. A literature review on pore transport mechanisms, physical structure of membranes, and module configuration of industrial membrane processes has been made to obtain a better understanding of membrane performance in gas separations. The research experience in decomposing polymer resins for ablative composites has stimulated a research interest in developing a dynamic model for membrane processes, incorporating a temperature effects on material and fluid properties. Brief summaries of the reviewed literature, permeability experiments, and process modeling are presented in this report.

  13. Numerical simulation of gas metal arc welding temperature field

    Institute of Scientific and Technical Information of China (English)

    Zheng Zhentai; Shan Ping; Hu Shengsun; Wei Xinwei; Yang Jinglei

    2006-01-01

    The infrared camera is used to investigate the temperature field of gas metal arc welding. The results show that the temperature distribution of weld pool and adjacent area appears cone shape. A new heat source model combined by Gaussian distribution heat source of the arc and conical distribution heat source of the droplet is set up based on the experimental results,and with the combined boundary conditions, the temperature field of gas metal arc welding is simulated using finite element method. According to the comparison between the results of experiment and simulation in temperature field shows that the new combined heat source model is more accurate and effective than the Gauss heat source model.

  14. Laser mass spectrometry for high sensitive and multi-com- ponent analysis of exhaust gas from vehicles

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Laser mass spectrometry is a newly developed method for pollutantdetection. It combines resonance-en- hanced multiphoton ionization (REMPI) and time-of-flight mass spectro- metry (TOF-MS). It may detect pollutants with high sensitivity, high selectivity and in a multi-com- ponent way. In this note, laser mass spectrometry was used to detect the pollutants in exhaust gases from vehicles. With one-color REMPI (at 266 nm), several aromatic hydrocarbons, including benzene, toluene, xylene, C3-benzene, etc., were detected. These substances were selectively ionized by (1+1) REMPI and their mass resolution was detected by a TOF mass spectrometer. And a quantitative analysis was achieved.

  15. Microstructural Characterization of Low Temperature Gas Nitrided Martensitic Stainless Steel

    DEFF Research Database (Denmark)

    Fernandes, Frederico Augusto Pires; Christiansen, Thomas Lundin; Somers, Marcel A. J.

    2015-01-01

    The present work presents microstructural investigations of the surface zone of low temperature gas nitrided precipitation hardening martensitic stainless steel AISI 630. Grazing incidence X-ray diffraction was applied to investigate the present phases after successive removal of very thin sections...... of the sample surface. The development of epsilon nitride, expanded austenite and expanded martensite resulted from the low temperature nitriding treatments. The microstructural features, hardness and phase composition are discussed with emphasis on the influence of nitriding duration and nitriding potential....

  16. Temperatures of dust and gas in S~140

    CERN Document Server

    Koumpia, E; Ossenkopf, V; van der Tak, F F S; Mookerjea, B; Fuente, A; Kramer, C

    2015-01-01

    In dense parts of interstellar clouds (> 10^5 cm^-3), dust & gas are expected to be in thermal equilibrium, being coupled via collisions. However, previous studies have shown that the temperatures of the dust & gas may remain decoupled even at higher densities. We study in detail the temperatures of dust & gas in the photon-dominated region S 140, especially around the deeply embedded infrared sources IRS 1-3 and at the ionization front. We derive the dust temperature and column density by combining Herschel PACS continuum observations with SOFIA observations at 37 $\\mu$m and SCUBA at 450 $\\mu$m. We model these observations using greybody fits and the DUSTY radiative transfer code. For the gas part we use RADEX to model the CO 1-0, CO 2-1, 13CO 1-0 and C18O 1-0 emission lines mapped with the IRAM-30m over a 4' field. Around IRS 1-3, we use HIFI observations of single-points and cuts in CO 9-8, 13CO 10-9 and C18O 9-8 to constrain the amount of warm gas, using the best fitting dust model derived wit...

  17. Estimated times to exhaustion and power outputs at the gas exchange threshold, physical working capacity at the rating of perceived exertion threshold, and respiratory compensation point.

    Science.gov (United States)

    Bergstrom, Haley C; Housh, Terry J; Zuniga, Jorge M; Camic, Clayton L; Traylor, Daniel A; Schmidt, Richard J; Johnson, Glen O

    2012-10-01

    The purposes of this study were to compare the power outputs and estimated times to exhaustion (T(lim)) at the gas exchange threshold (GET), physical working capacity at the rating of perceived exertion threshold (PWC(RPE)), and respiratory compensation point (RCP). Three male and 5 female subjects (mean ± SD: age, 22.4 ± 2.8 years) performed an incremental test to exhaustion on an electronically braked cycle ergometer to determine peak oxygen consumption rate, GET, and RCP. The PWC(RPE) was determined from ratings of perceived exertion data recorded during 3 continuous workbouts to exhaustion. The estimated T(lim) values for each subject at GET, PWC(RPE), and RCP were determined from power curve analyses (T(lim) = ax(b)). The results indicated that the PWC(RPE) (176 ± 55 W) was not significantly different from RCP (181 ± 54 W); however, GET (155 ± 42 W) was significantly less than PWC(RPE) and RCP. The estimated T(lim) for the GET (26.1 ± 9.8 min) was significantly greater than PWC(RPE) (14.6 ± 5.6 min) and RCP (11.2 ± 3.1 min). The PWC(RPE) occurred at a mean power output that was 13.5% greater than the GET and, therefore, it is likely that the perception of effort is not driven by the same mechanism that underlies the GET (i.e., lactate buffering). Furthermore, the PWC(RPE) and RCP were not significantly different and, therefore, these thresholds may be associated with the same mechanisms of fatigue, such as increased levels of interstitial and (or) arterial [K⁺]. PMID:22716291

  18. Low temperature catalytic combustion of natural gas - hydrogen - air mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Newson, E.; Roth, F. von; Hottinger, P.; Truong, T.B. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The low temperature catalytic combustion of natural gas - air mixtures would allow the development of no-NO{sub x} burners for heating and power applications. Using commercially available catalysts, the room temperature ignition of methane-propane-air mixtures has been shown in laboratory reactors with combustion efficiencies over 95% and maximum temperatures less than 700{sup o}C. After a 500 hour stability test, severe deactivation of both methane and propane oxidation functions was observed. In cooperation with industrial partners, scaleup to 3 kW is being investigated together with startup dynamics and catalyst stability. (author) 3 figs., 3 refs.

  19. Kinetic Description of a Finite Temperature Meson Gas

    CERN Document Server

    Tan, Z G; Terranova, S; Bonasera, A; Tan, Zhi Guang; Zhou, Dai-Mei

    2006-01-01

    A transport model based on the mean free path approach for an interacting meson system at finite temperatures is discussed. A transition to a quark gluon plasma is included within the framework of the bag model. We discuss some calculations for a pure meson gas where the Hagedorn limiting temperature is reproduced when including the experimentally observed resonances. Next we include the possibility for a QGP formation based on the MIT bag model. The results obtained compare very well with Lattice QCD calculations. In particular the cross over to the QGP at about 175 MeV temperature is nicely reproduced.

  20. Exhaust gas emissions and environmental effects by use of rape seed oil based fuels in agricultural tractors; Schadstoffemissionen und Umweltwirkungen bei Verwendung von Rapsoelkraftstoffen in der Landwirtschaft

    Energy Technology Data Exchange (ETDEWEB)

    Krahl, J.; Vellguth, G.; Munack, A.; Stalder, K.; Bahadir, M.

    1996-01-01

    The use of biofuels can only be supported, if their effects on environment and human health are well known. So the exhaust gases of seven different Diesel engines fueled with rape seed oil or RME were analyzed and compared to those from Diesel fuel (DF). As motor test procedure the 5-mode cycle was chosen, which simulates the typical load of agricultural tractors. Besides the determination of the regulated and nonregulated exhaust gas compounds, some engines were examined with regard to the cytotoxic and mutagenic potentials of their particulates as well. The result of all investigations shows that RME has definite advantages when it is used in rural areas. (orig.) [Deutsch] Oekologische Aspekte, die Endlichkeit fossiler Ressourcen und das Bestreben, die landwirtschaftlichen Strukturen zu erhalten, motivieren die Verwendung nachwachsender Rohstoffe. In der Bundesforschungsanstalt fuer Landwirtschaft (FAL) wird seit den 70er Jahren die technische Nutzung von Rapsoel als Alternativkraftstoff untersucht. Schon sehr frueh zeigte sich, dass reines Rapsoel nicht langfristig in konventionellen Dieselmotoren einsetzbar ist, da schwere Motorschaeden die Folge sind. Um Rapsoel dennoch als Kraftstoff nutzen zu koennen, muss entweder der Motor oder der Kraftstoff veraendert werden. Durch motorische Sonderkonstruktionen auf der einen oder die Umesterung des Rapsoels - meist zu Rapsoelmethylester (RME) - auf der anderen Seite gelingt es, Rapsoel als fluessigen Energietraeger zu verwenden. Mit RME, der in seinen physikalischen Eigenschaften dem Dieselkraftstoff (DK) sehr aehnelt, wird seit 1982 in der Versuchsstation der FAL ein Traktor erfolgreich betrieben, Bild 1. Analog dazu muessen auch modifizierte Motoren ihre Tauglichkeit im Langzeitversuch unter Beweis stellen. (orig.)

  1. Effect of cooled EGR on performance and exhaust gas emissions in EFI spark ignition engine fueled by gasoline and wet methanol blends

    Science.gov (United States)

    Rohadi, Heru; Syaiful, Bae, Myung-Whan

    2016-06-01

    Fuel needs, especially the transport sector is still dominated by fossil fuels which are non-renewable. However, oil reserves are very limited. Furthermore, the hazardous components produced by internal combustion engine forces many researchers to consider with alternative fuel which is environmental friendly and renewable sources. Therefore, this study intends to investigate the impact of cooled EGR on the performance and exhaust gas emissions in the gasoline engine fueled by gasoline and wet methanol blends. The percentage of wet methanol blended with gasoline is in the range of 5 to 15% in a volume base. The experiment was performed at the variation of engine speeds from 2500 to 4000 rpm with 500 intervals. The re-circulated exhaust gasses into combustion chamber was 5%. The experiment was performed at the constant engine speed. The results show that the use of cooled EGR with wet methanol of 10% increases the brake torque up to 21.3%. The brake thermal efficiency increases approximately 39.6% using cooled EGR in the case of the engine fueled by 15% wet methanol. Brake specific fuel consumption for the engine using EGR fueled by 10% wet methanol decreases up to 23% at the engine speed of 2500 rpm. The reduction of CO, O2 and HC emissions was found, while CO2 increases.

  2. Numerical simulation of wall temperature on gas pipeline due to radiation of natural gas during combustion

    Directory of Open Access Journals (Sweden)

    Ilić Marko N.

    2012-01-01

    Full Text Available This paper presents one of the possible hazardous situations during transportation of gas through the international pipeline. It describes the case when at high-pressure gas pipeline, due to mechanical or chemical effect, cracks and a gas leakage appears and the gas is somehow triggered to burn. As a consequence of heat impingement on the pipe surface, change of material properties (decreasing of strength at high temperatures will occur. In order to avoid greater rapture a reasonable pressure relief rate needs to be applied. Standards in this particular domain of depressurizing procedure are not so exact (DIN EN ISO 23251; API 521. This paper was a part of the project to make initial contribution in defining the appropriate procedure of gas operator behaving during the rare gas leakage and burning situations on pipeline network. The main part of the work consists of two calculations. The first is the numerical simulation of heat radiation of combustible gas, which affects the pipeline, done in the FLUENT software. The second is the implementation of obtained results as a boundary condition in an additional calculation of time resolved wall temperature of the pipe under consideration this temperature depending on the incident flux as well as a number of other heat flow rates, using the Matlab. Simulations were done with the help of the “E.ON Ruhrgas AG” in Essen.

  3. 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

  4. Utilisation of CO2, fixation of nitrogen and exhaust gas cleaning in electric discharge with electrode catalysis

    International Nuclear Information System (INIS)

    The method reported here provides a contribution to CO2 utilisation, nitrogen fixation and combustion exhaust cleaning using synergetic effect of electric discharge with heterogeneous catalysis on electrodes. The efficiency of CO2 removal is about 40-65%. The process of CO2 removal is always accompanied by NOx, VOC, SX and other component removal and is connected with O2 formation. The final product of process is powder with fractal microstructure, low specific weight, water insoluble suitable for use as nitrogen containing fertilizer. The main component (95%) of solid product is amorphous condensate of amino acids with about 5% of metal organic compound with catalytic properties. The condensate has character of statistical proteinoid. Its creation seems to play important role during formation of life in pre-biotic Earth

  5. 46 CFR 119.430 - Engine exhaust pipe installation.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Engine exhaust pipe installation. 119.430 Section 119... INSTALLATION Specific Machinery Requirements § 119.430 Engine exhaust pipe installation. (a) The design of all... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must...

  6. NOx abatement in the exhaust of lean-burn natural gas engines over Ag-supported γ-Al2O3 catalysts

    Science.gov (United States)

    Azizi, Y.; Kambolis, A.; Boréave, A.; Giroir-Fendler, A.; Retailleau-Mevel, L.; Guiot, B.; Marchand, O.; Walter, M.; Desse, M.-L.; Marchin, L.; Vernoux, P.

    2016-04-01

    A series of Ag catalysts supported on γ-Al2O3, including two different γ-Al2O3 supports and various Ag loadings (2-8 wt.%), was prepared, characterized (SEM, TEM, BET, physisorption, TPR, NH3-TPD) and tested for the selective catalytic reduction of NOx by CH4 for lean-burn natural gas engines exhausts. The catalysts containing 2 wt.% Ag supported on γ-Al2O3 were found to be most efficient for the NOx reduction into N2 with a maximal conversion of 23% at 650 °C. This activity was clearly linked with the ability of the catalyst to concomitantly produce CO, via the methane steam reforming, and NO2. The presence of small AgOx nanoparticles seems to be crucial for the methane activation and NOx reduction.

  7. Optimized Feature Extraction for Temperature-Modulated Gas Sensors

    Directory of Open Access Journals (Sweden)

    Alexander Vergara

    2009-01-01

    Full Text Available One of the most serious limitations to the practical utilization of solid-state gas sensors is the drift of their signal. Even if drift is rooted in the chemical and physical processes occurring in the sensor, improved signal processing is generally considered as a methodology to increase sensors stability. Several studies evidenced the augmented stability of time variable signals elicited by the modulation of either the gas concentration or the operating temperature. Furthermore, when time-variable signals are used, the extraction of features can be accomplished in shorter time with respect to the time necessary to calculate the usual features defined in steady-state conditions. In this paper, we discuss the stability properties of distinct dynamic features using an array of metal oxide semiconductors gas sensors whose working temperature is modulated with optimized multisinusoidal signals. Experiments were aimed at measuring the dispersion of sensors features in repeated sequences of a limited number of experimental conditions. Results evidenced that the features extracted during the temperature modulation reduce the multidimensional data dispersion among repeated measurements. In particular, the Energy Signal Vector provided an almost constant classification rate along the time with respect to the temperature modulation.

  8. 汽车燃料和排放物的快速气相色谱分析%HIGH-SPEED GAS CHROMATOGRAPHY ANALYSIS OF AUTOMOTIVE FUELS AND EXHAUST SPECIES

    Institute of Scientific and Technical Information of China (English)

    AKIYAMAK

    2003-01-01

    The chemical analysis of organic compounds in the automotive fuels and exhaust species is an extremely important and complex procedure. For these compounds analysis, gas chromatography is the most widely method used because of its excellent selectivity, and wide dynamic concentration range. Although, analysis time of automotive fuels and exhausts are very long because these are complex mixtures, and target compounds in these samples are very low concentration. Concentrations of some species for example 13-butadiene are change after collection. Long analysis turnaround time make cost increase. The high-speed gas chromatography analysis techniques of automotive fuels and exhaust species are developed, because to decrease turnaround of analysis time is very important for cutback the cost of experiments and ensure of reliability.

  9. 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

  10. Gas temperature measurement in combustors by use of suction pyrometry

    International Nuclear Information System (INIS)

    The purpose of this paper is to introduce new measurement techniques and configurations in gas suction pyrometry. A detailed description of three types of mini-pyrometers for the study of burning and heat transfer processes is presented. A suction pyrometer whose inner cavity is insulated by ceramic wool was developed for use in high velocity and high temperature jets of combustion products. A second type of pyrometer was developed for measuring oscillating gas temperatures, based on a micron-size sensitive head located in a spherical piece of fibrous material, through which the hot gases are aspirated. A third pyrometer was developed with an electrically-heated thermocouple and pulsed suction for use in low velocity 'dirty' gaseous media

  11. Gas detection using low-temperature reduced graphene oxide sheets

    Science.gov (United States)

    Lu, Ganhua; Ocola, Leonidas E.; Chen, Junhong

    2009-02-01

    We demonstrate a high-performance gas sensor using partially reduced graphene oxide (GO) sheets obtained through low-temperature step annealing (300 °C at maximum) in argon flow at atmospheric pressure. The electrical conductance of GO was measured after each heating cycle to interpret the level of reduction. The thermally reduced GO showed p-type semiconducting behavior in ambient conditions and were responsive to low-concentration NO2 diluted in air at room temperature. The sensitivity is attributed to the electron transfer from the reduced GO to adsorbed NO2, which leads to enriched hole concentration and enhanced electrical conduction in the reduced GO sheet.

  12. Chemical relaxation times in a hadron gas at finite temperature

    CERN Document Server

    Goity, J L

    1993-01-01

    The relaxation times of particle numbers in hot hadronic matter with vanishing baryon number are estimated using the ideal gas approximation and taking into account resonance decays and annihilation processes as the only sources of particle number fluctuations. Near the QCD critical temperature the longest relaxation times turn out to be of the order of 10 fm and grow roughly exponentially to become of the order of $10^{3}$ fm at temperatures around 100 MeV. As a consequence of such long relaxation times, a clear departure from chemical equilibrium must be observed in the momentum distribution of secondary particles produced in high energy nuclear collisions.

  13. Physical processes in low-temperature gas-dynamic lasers

    Energy Technology Data Exchange (ETDEWEB)

    Konyukhov, V.K. (ed.)

    1990-01-01

    The book focuses on the coupled mode CO[sub 2] gasdynamic laser (16-22 [mu]m) and the feasibility of an H[sub 2]O or D[sub 2]O gasdynamic laser (in the submilimeter region) that could operate at exceptionally low stagnation temperatures. The text contains two major parts with eight chapters. In the first part, this text covers an overview of gas dynamic lasers in terms of vibrationally nonequilibrium processes for a homogeneous gas system and also for a gas-aerosol system with heterogeneous water condensation. The latter part is an excellent resource of a spectroscopic data base, which is useful in predicting performance characteristics of gasdynamic lasers. The last five chapters contain a detailed theoretical analysis and experimental results on rotationally nonequilibrium processes of both H[sub 2]O and D[sub 2]O in biphase (vapor liquid) supersonic flow. The role of rotational nonequilibrium has not received attention in gas dynamic lasers in the case of water-free condensation. The experimental measurements using high resolution spectroscopic studies in this text, however, indicate that a theoretical analysis of gasdynamic laser should take account the presence of effects of rotational non-equilibrium, particularly in rarefied supersonic jet streams with high water vapor concentration at low temperature. Similar rotational nonequilibrium effects were previously treated for HF or DF molecules when studying high energy chemical lasers.

  14. Enhancement of efficiency and environmental friendliness of driving gas turbines by integrating of existing turbomachine and high temperature ceramic overstructure

    Energy Technology Data Exchange (ETDEWEB)

    Soudarev, A.V.; Souryaninov, A.A.; Tikhoplav, V.Y. [Boyko Research Engineering, St. Petersburg (Russian Federation). Ceramic Heat Engines Center; Kozlov, S.I. [JSC GAZPROM, Moscow (Russian Federation). Dept. of Strategy Policy

    2004-07-01

    This paper discussed the development of a gas turbine engine (GTE) with a high temperature ceramic overstructure used as a high pressure turbocompressor with a low-toxic combustor installed between its compressor and turbine. The GTE was proposed as an environmentally friendly means of upgrading the 4000 gas turbine units currently being used in Russia. A pilot program using the GTE showed efficiency increases of 28 per cent, while nitrogen oxide (NO{sub x}) emissions were reduced to 12.5 ppm instead of 50 ppm. Initial gas temperatures were then increased through the use of a small ceramic air heater. Application of the ceramic overstructure allowed an increase in efficiency along with a simultaneous decrease in exhaust gas emissions. Fuel flow across the GTE was then compared with a conventional gas metal element design. Production of base-line single-shaft and double-support engines has now begun. A plant upgrade is also being planned using the ceramic overstructure, in which a Brayton cycle heat scheme will be used to increase maximum gas temperature and change-over to the double-shaft design. The second shaft will be formed as a turbo-compressor unit in a ceramic single-stage axial turbine and centrifugal double-stage compressor that will include the annular combustor with a ceramic liner and an air-lubricated gas static thrust-journal support component. A system analysis of the design has shown that the alumo-boron-nitride ceramics were the most appropriate materials. An equistrong diffusion jointing and elasto-erosion treatment technique was developed for the alumo-boron-nitride ceramic composites to extend the capability of components with a complex geometry. It was concluded that full-scale plant thermodynamic studies have demonstrated the feasibility of the design. 10 refs., 3 tabs., 6 figs.

  15. High-Temperature Gas-Cooled Test Reactor Point Design

    Energy Technology Data Exchange (ETDEWEB)

    Sterbentz, James William [Idaho National Laboratory; Bayless, Paul David [Idaho National Laboratory; Nelson, Lee Orville [Idaho National Laboratory; Gougar, Hans David [Idaho National Laboratory; Kinsey, James Carl [Idaho National Laboratory; Strydom, Gerhard [Idaho National Laboratory; Kumar, Akansha [Idaho National Laboratory

    2016-04-01

    A point design has been developed for a 200 MW high-temperature gas-cooled test reactor. The point design concept uses standard prismatic blocks and 15.5% enriched UCO fuel. Reactor physics and thermal-hydraulics simulations have been performed to characterize the capabilities of the design. In addition to the technical data, overviews are provided on the technological readiness level, licensing approach and costs.

  16. Exhaust gas emissions from diesel-engines driven by rape seed oil methyl ester, rape seed oil and diesel fuel - an evaluation of laboratory and vehicle fleet test results

    Energy Technology Data Exchange (ETDEWEB)

    Kern, C.; Widmann, B. [Technische Univ. Muenchen (Germany)

    1999-11-01

    Diesel fuels from rape seed oil can contribute to a reduction of CO{sub 2}-emissions and save mineral fuel resources. But at the same time other emission components, which have an environmental or health impact, must be compared with the exhaust gas emissions from presently used mineral diesel fuels. This study compares various results from vehicle emission tests, concentrating on personnel vehicles and rape seed oil methyl ester (RME), to show a tendency if there is a similar, lower or even higher output of critical exhaust gas components. The results vary in a wide range: for motors with a generally high emission level there is a tendency for lower emissions with RME, but for motors with a sophisticated technology (e.g. injection technique and exhaust gas cleaning) the differences between the fuels become more and more insignificant, so that general statements about advantages cannot be made. The influence of modern motor and exhaust gas cleaning technology seems more important here than the fuel properties. Even through the differences between the fuels in emission components are not significant in general it can be stated that the advantages concerning the reduction of CO{sub 2}-emission and biodegradability remain. (orig.)

  17. Exhaust gas emissions from diesel-engines driven by rape seed oil methyl ester, rape seed oil and diesel fuel - an evaluation of laboratory and vehicle fleet test results

    Energy Technology Data Exchange (ETDEWEB)

    Kern, C.; Widmann, B. (Technische Univ. Muenchen (Germany))

    1999-01-01

    Diesel fuels from rape seed oil can contribute to a reduction of CO[sub 2]-emissions and save mineral fuel resources. But at the same time other emission components, which have an environmental or health impact, must be compared with the exhaust gas emissions from presently used mineral diesel fuels. This study compares various results from vehicle emission tests, concentrating on personnel vehicles and rape seed oil methyl ester (RME), to show a tendency if there is a similar, lower or even higher output of critical exhaust gas components. The results vary in a wide range: for motors with a generally high emission level there is a tendency for lower emissions with RME, but for motors with a sophisticated technology (e.g. injection technique and exhaust gas cleaning) the differences between the fuels become more and more insignificant, so that general statements about advantages cannot be made. The influence of modern motor and exhaust gas cleaning technology seems more important here than the fuel properties. Even through the differences between the fuels in emission components are not significant in general it can be stated that the advantages concerning the reduction of CO[sub 2]-emission and biodegradability remain. (orig.)

  18. Gas Temperature and Carrier Gas effects on nanoparticle formation in silane plasmas

    Science.gov (United States)

    Bhandarkar, Upendra; Kortshagen, Uwe; Girshick, Steven

    2002-10-01

    The improvement in the electronic properties of thin silicon films deposited under plasma conditions that favor particle formation has spurred further research interest in the particle properties as well as the pathways leading to particle formation. We have been carrying out simulations to study particle generation in silane processing plasmas used in such deposition processes. Our zero-dimensional model solves for gas and surface chemistry, particle growth due to coagulation and surface growth, particle charging and plasma properties. We have been studying the effect of gas temperature and carrier gas that has been found to influence the particle nucleation time in experiments. At present our simulations suggest that these effects may primarily be caused by diffusion. An increase in the gas temperature or a lighter carrier gas speed up the diffusion of clusters and newly formed ``nuclei''. A decrease in the initial nuclei population has further effects in slowing down growth due to coagulation. This could have important implications in devicing methods to control the particle growth in plasmas. We will present results obtained from these calculations that also include the effect of gas pressure and input power.

  19. Non-intrusive measurement of hot gas temperature in a gas turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    DeSilva, Upul P.; Claussen, Heiko; Yan, Michelle Xiaohong; Rosca, Justinian; Ulerich, Nancy H.

    2016-09-27

    A method and apparatus for operating a gas turbine engine including determining a temperature of a working gas at a predetermined axial location within the engine. An acoustic signal is encoded with a distinct signature defined by a set of predetermined frequencies transmitted as a non-broadband signal. Acoustic signals are transmitted from an acoustic transmitter located at a predetermined axial location along the flow path of the gas turbine engine. A received signal is compared to one or more transmitted signals to identify a similarity of the received signal to a transmitted signal to identify a transmission time for the received signal. A time-of-flight is determined for the signal and the time-of-flight for the signal is processed to determine a temperature in a region of the predetermined axial location.

  20. Hybrid high temperature gas-cooled reactor, thermonuclear fusion

    International Nuclear Information System (INIS)

    The project of a multi-purpose high temperature gas-cooled reactor started in 1969. The Atomic Energy Commission, Japan, approved in 1980 the budget for the design study of the experimental reactor. The conceptual design is in progress. The manufacturing of coated fuel pellets and the test method have been developed. The study of graphite structure is carried out. Corrosion and creep tests are made to obtain the knowledge concerning the metals in high temperature helium gas. The engineering study of various machines and structures operating at high temperature is performed. International cooperative works are considered. The experimental reactor will be critical in 1987. A critical plasma test facility, JT-60, has been constructed at the Japan Atomic Energy Research Institute. As the theoretical work on plasma confinement, the evaluation of the critical beta value of JT-60 was made. By high temperature neutral beam injection, the slowing down and heating processes of high energy particles are studied. The development of a non-circular cross-section tokamak is in progress. The construction of JT-60 will be completed in 1984. Study concerning superconducting magnets is considered. Japan is one of the members of INTOR project. (Kato, T.)

  1. Generating usable and safe CO{sub 2} for enrichment of greenhouses from the exhaust gas of a biomass heating system

    Energy Technology Data Exchange (ETDEWEB)

    Dion, L.M.; Lefsrud, M. [McGill Univ., Macdonald Campus, Ste-Anne-deBellevue, PQ (Canada). Dept. of Bioresource Engineering

    2010-07-01

    This study demonstrated the use of biomass as a renewable fuel to enrich a greenhouse with carbon dioxide (CO{sub 2}). CO{sub 2} enrichment of greenhouses has been shown to improve crop production whether it occurs from liquid CO{sub 2} or combustion of fossil fuels. Biomass, in the form of wood chips or pellets, has received much interest as a sustainable and economically viable alternative to heat greenhouses. As such, the opportunity exists to convert exhaust gases from a greenhouse wood heating system into a useful resource. CO{sub 2} can be extracted from flue gas via membrane separation instead of electrostatic precipitators. This technique has shown potential for large industries trying to reduce and isolate CO{sub 2} emissions for sequestration and may be applicable to the greenhouse industry. Some research has also been done with wet scrubbers using catalysts to obtain plant fertilizers. Sulphur dioxide (SO{sub 2}) and nitrogen (NO) emissions can be stripped from flue gas to form ammonium sulphate as a valuable byproduct for fertilizer markets. This study will review the potential of these techniques in the summer of 2010 when experiments will be conducted at the Macdonald Campus of McGill University.

  2. 论多晶硅生产废气回收的必要性%On the Necessity for Recycling of Exhaust Gas in Polysilicon Production

    Institute of Scientific and Technical Information of China (English)

    陆大军

    2011-01-01

    介绍了某企业多晶硅生产过程中废气的来源和组成,对废气回收的必要性进行了论述。%In a 3,000 t/a polysilicon project with modified Siemens process,the low-boiling-point compositions which are produced in production systems are not recycled for some design and production reasons.As a result,the severe exceeding standard of low-boiling-point compositions in the production systems makes the systems always excess pressure,which makes it is not easy for the safety operation for the system.Besides,the recycling systems do not classify the discharge,then the off gas scrubber system do not work properly and the treatment cost is increased.This makes a lot of material waste and increases the production cost.In order to save production costs and reduce the treatment costs,it is urgent to recycle the exhaust gas.

  3. Lithographically fabricated silicon microreactor for operando QEXAFS studies in exhaust gas catalysis during simulation of a standard driving cycle

    Science.gov (United States)

    Doronkin, D. E.; Baier, S.; Sheppard, T.; Benzi, F.; Grunwaldt, J.-D.

    2016-05-01

    Selective catalytic reduction of NOx by ammonia over Cu-ZSM-5 was monitored by operando QEXAFS during simulation of the New European Driving Cycle. The required fast temperature transients were realized using a novel silicon microreactor, enabling simultaneous spectroscopic and kinetic analysis by X-ray absorption spectroscopy (XAS) and mass spectrometry (MS). Periods of high temperature were correlated to an increase in both N2 production and change of coordination of Cu sites. This operando approach using Si microreactors can be applied to other heterogeneous catalytic systems involving fast temperature transients.

  4. High-Temperature Gas Sensor Array (Electronic Nose) Demonstrated

    Science.gov (United States)

    Hunter, Gary W.

    2002-01-01

    The ability to measure emissions from aeronautic engines and in commercial applications such as automotive emission control and chemical process monitoring is a necessary first step if one is going to actively control those emissions. One single sensor will not give all the information necessary to determine the chemical composition of a high-temperature, harsh environment. Rather, an array of gas sensor arrays--in effect, a high-temperature electronic "nose"--is necessary to characterize the chemical constituents of a diverse, high-temperature environment, such as an emissions stream. The signals produced by this nose could be analyzed to determine the constituents of the emission stream. Although commercial electronic noses for near-room temperature applications exist, they often depend significantly on lower temperature materials or only one sensor type. A separate development effort necessary for a high-temperature electronic nose is being undertaken by the NASA Glenn Research Center, Case Western Reserve University, Ohio State University, and Makel Engineering, Inc. The sensors are specially designed for hightemperature environments. A first-generation high-temperature electronic nose has been demonstrated on a modified automotive engine. This nose sensor array was composed of sensors designed for hightemperature environments fabricated using microelectromechanical-systems- (MEMS-) based technology. The array included a tin-oxide-based sensor doped for nitrogen oxide (NOx) sensitivity, a SiC-based hydrocarbon (CxHy) sensor, and an oxygen sensor (O2). These sensors operate on different principles--resistor, diode, and electrochemical cell, respectively--and each sensor has very different responses to the individual gases in the environment. A picture showing the sensor head for the array is shown in the photograph on the left and the sensors installed in the engine are shown in the photograph on the right. Electronics are interfaced with the sensors for

  5. Optimum Reactor Outlet Temperatures for High Temperature Gas-Cooled Reactors Integrated with Industrial Processes

    Energy Technology Data Exchange (ETDEWEB)

    Lee O. Nelson

    2011-04-01

    This report summarizes the results of a temperature sensitivity study conducted to identify the optimum reactor operating temperatures for producing the heat and hydrogen required for industrial processes associated with the proposed new high temperature gas-cooled reactor. This study assumed that primary steam outputs of the reactor were delivered at 17 MPa and 540°C and the helium coolant was delivered at 7 MPa at 625–925°C. The secondary outputs of were electricity and hydrogen. For the power generation analysis, it was assumed that the power cycle efficiency was 66% of the maximum theoretical efficiency of the Carnot thermodynamic cycle. Hydrogen was generated via the hightemperature steam electrolysis or the steam methane reforming process. The study indicates that optimum or a range of reactor outlet temperatures could be identified to further refine the process evaluations that were developed for high temperature gas-cooled reactor-integrated production of synthetic transportation fuels, ammonia, and ammonia derivatives, oil from unconventional sources, and substitute natural gas from coal.

  6. Gas hydrate dissociation in sediments: Pressure-temperature evolution

    Science.gov (United States)

    Kwon, Tae-Hyuk; Cho, Gye-Chun; Santamarina, J. Carlos

    2008-03-01

    Hydrate-bearing sediments may destabilize spontaneously as part of geological processes, unavoidably during petroleum drilling/production operations or intentionally as part of gas extraction from the hydrate itself. In all cases, high pore fluid pressure generation is anticipated during hydrate dissociation. A comprehensive formulation is derived for the prediction of fluid pressure evolution in hydrate-bearing sediments subjected to thermal stimulation without mass transfer. The formulation considers pressure- and temperature-dependent volume changes in all phases, effective stress-controlled sediment compressibility, capillarity, and the relative solubilities of fluids. Salient implications are explored through parametric studies. The model properly reproduces experimental data, including the PT evolution along the phase boundary during dissociation and the effect of capillarity. Pore fluid pressure generation is proportional to the initial hydrate fraction and the sediment bulk stiffness; is inversely proportional to the initial gas fraction and gas solubility; and is limited by changes in effective stress that cause the failure of the sediment. When the sediment stiffness is high, the generated pore pressure reflects thermal and pressure changes in water, hydrate, and mineral densities. Comparative analyses for CO2 and CH4 highlight the role of gas solubility in excess pore fluid pressure generation. Dissociation in small pores experiences melting point depression due to changes in water activity, and lower pore fluid pressure generation due to the higher gas pressure in small gas bubbles. Capillarity effects may be disregarded in silts and sands, when hydrates are present in nodules and lenses and when the sediment experiences hydraulic fracture.

  7. The Freestyle RTO Incinerator for both Exhaust Gas and Phenolic Wastewater Treatment%可以同时处理废气与有机废液的自由式RTO焚烧炉

    Institute of Scientific and Technical Information of China (English)

    曾光龙

    2014-01-01

    For current RTO incinerator, most of them are only applied for exhaust gas, or trash-burning separately, but no such RTO incinerator that can be applied for all exhaust gas, phenolic wastewater and organic solid trash simultaneously till now. The treatment of phenolic wastewater has been a long-standing problem of phenolic resin industrial, through the heat made by exhaust gas burning to burn phenolic wastewater and solid trash, the RTO incinerator will be multipurpose and more energy-saving . Since freestyle RTO incinerator honeycomb ceramic is placed horizontally, incinerator furnace temperatures up to 850-950℃, wastewater into the incinerator will not come into contact with honeycomb ceramic, so it is not only suitable for gas processing, but will be also suitable for phenolic wastewater (including industrial waste water) and organic solid trash treatment, a complete decomposition of oxidation of organics, the fuel consumption is very low. Consider the advantages of simple structure, energy-saving, low cost and maintenance, and wider applications, the freestyle RTO incinerator will be very valuable for promotion.%当前的焚烧炉,多数是专用于焚烧有机废气,或专用于焚烧垃圾,未见过可以同时进行有机废气、废液、有机固体废弃物处理的RTO焚烧炉。含酚废水处理一直是酚醛树脂工业的老大难问题,利用燃烧有机废气产生热量,烧掉这些有机废液与有机固体废弃物,可以达到一炉多用又更加节能目的。由于自由式RTO焚烧炉的蜂窝陶瓷是水平摆放,焚烧炉炉膛的温度高达850-950℃,废水进入焚烧炉不会接触到蜂窝陶瓷,因此它不仅适用于废气处理,而且也适用于含酚废水(包含工业废液),以及有机固体废弃物的处理,有机物氧化分解彻底,燃料消耗非常低。由于自由式RTO的结构简单,节能,造价低,维护费用低,用途更加广泛,因此非常有推广价值。

  8. High-temperature gas effects on aerodynamic characteristics of waverider

    Institute of Scientific and Technical Information of China (English)

    Liu Jun; Li Kai; Liu Weiqiang

    2015-01-01

    This paper focuses on the analysis of high-temperature effect on a conical waverider and it is a typical configuration of near space vehicles. Two different gas models are used in the numerical simulations, namely the thermochemical non-equilibrium and perfect gas models. The non-equilibrium flow simulations are conducted with the usage of the parallel non-equilibrium pro-gram developed by the authors while the perfect gas flow simulations are carried out with the com-mercial software Fluent. The non-equilibrium code is validated with experimental results and grid sensitivity analysis is performed as well. Then, numerical simulations of the flow around the conical waverider with the two gas models are conducted. In the results, differences in the flow structures as well as aerodynamic performances of the conical waverider are compared. It is found that the thermochemical non-equilibrium effect is significant mainly near the windward boundary layer at the tail of the waverider, and the non-equilibrium influence makes the pressure center move forward to about 0.57%of the whole craft’s length at the altitude of 60 km.

  9. Low temperature dynamic characteristics of a three-way catalytic converter

    Energy Technology Data Exchange (ETDEWEB)

    Balenovic, M.; Backx, A.C.P.M. [Technische Univ. Eindhoven (Netherlands). Dept. of Electrical Engineering; Harmsen, J.M.A.; Hoebink, J.H.B.J. [Technische Univ. Eindhoven (Netherlands). Lab. of Chemical Reactor Engineering

    2001-07-01

    A mathematical model of a three-way catalytic converter based on a detailed chemical kinetic model has been created mainly to analyze the converter's dynamic behavior at low temperatures. The light-off process of the converter is analyzed in detail. Competition of species for empty noble metal surface determines the light-off characteristic, as inhibition processes increase light-off temperatures of some exhaust gas components in the complete exhaust mixture. Perturbations of the exhaust gas mixture around stoichiometry can in certain conditions decrease the effect of inhibition and lower the light-off temperature for some exhaust components. (orig.)

  10. Low temperature dynamic characteristics of a three-way catalytic converter

    Energy Technology Data Exchange (ETDEWEB)

    Balenovic, M.; Backx, A.C.P.M. [Eindhoven University of Technology (Netherlands). Dept. of Electrical Engineering; Harmsen, J.M.A.; Hoebink, J.H.B.J. [Eindhoven University of Technology (Netherlands). Laboratory of Chemical Reactor Engineering

    2001-07-01

    A mathematical model of a three-way catalytic converter based on a detailed chemical kinetic model has been created mainly to analyze the converter's dynamic behavior at low temperatures. The light-off process of the converter is analyzed in detail. Competition of species for empty noble metal surface determines the light-off characteristic, as inhibition processes increase light-off temperatures of some exhaust gas components in the complete exhaust mixture. Perturbations of the exhaust gas mixture around stoichiometry can in certain conditions decrease the effect of inhibition and lower the light-off temperature for some exhaust components. (author)

  11. Thorium fueled high temperature gas cooled reactors. An assessment

    International Nuclear Information System (INIS)

    The use of thorium as a fertile fuel for the High Temperature Gas Cooled Reactor (HTR) instead of uranium has been reviewed. It has been concluded that the use of thorium might be beneficial to reduce the actinide waste production. To achieve a real advancement, the uranium of the spent fuel has to be recycled and the requested make-up fissile material for the fresh fuel has to be used in the form of highly-enriched uranium. A self-sustaining fuel cycle may be possible in the HTR of large core size, but this could reduce the inherent safety features of the design. (orig.)

  12. Fission gas release from uranium dioxide in high temperature transients

    International Nuclear Information System (INIS)

    The experiments described in this thesis investigate the kinetics and mechanisms for release of inert fission gases from irradiated fuel (uranium dioxide) during temperature transients, occuring in AGR type and PWR type reactors. A description is given of the fundamental physical properties of uranium dioxide with particular emphasis placed on the effects of irradiation damage and the build-up of fission product concentrations. A brief review is given of the principle mechanisms by which gases are thought to be released, covering both thermal and irradiation induced processes. The main design features of the Civil Advanced Gas Cooled Reactor (CAGR) and Pressurised Water Reactor (PWR) systems, concentrating on the specifications and normal operating conditions of the uranium dioxide fuel. This is followed by a brief description of the conditions anticipated during postulated reactor malfunctions. Two classes of fault are considered, in which the fuel temperature increases through loss of coolant efficiency or a rise in heat generation rate. (author)

  13. 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.

  14. 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%.

  15. Analysis and Discussion of the Exhaust Gas in Thermoelectric Industry%热电行业大气污染防治分析与探讨

    Institute of Scientific and Technical Information of China (English)

    姚德飞; 姚建松; 张建中; 潘淑萍

    2011-01-01

    According to monitoring results and the pollution characteristics of exhaust gas in thermoelectric industry, this article discusses the selection of different type of boiler and analyzes the sulfur dioxide and nitrogen oxide emission characteristics, and also compares the treatment efficiency of different pollution treatment facilities. The conclusion will provide references for environment impact forecasting and assessment.%根据浙江省热电行业特点以及其污染特征,结合已有的监测结果,对热电行业的污染防治与废气排放特点进行分析与总结,探讨热电行业的锅炉设备选型,合理的选择污染防治设施与工艺、废气污染物的达标可行性,并重点对该行业废气治理设施,以及废气中烟尘、二氧化硫、氮氧化物的排放情况进行分析与探讨,为热电行业的环境影响预测与评价提供参考。

  16. Exfoliated black phosphorus gas sensing properties at room temperature

    Science.gov (United States)

    Donarelli, M.; Ottaviano, L.; Giancaterini, L.; Fioravanti, G.; Perrozzi, F.; Cantalini, C.

    2016-06-01

    Room temperature gas sensing properties of chemically exfoliated black phosphorus (BP) to oxidizing (NO2, CO2) and reducing (NH3, H2, CO) gases in a dry air carrier have been reported. To study the gas sensing properties of BP, chemically exfoliated BP flakes have been drop casted on Si3N4 substrates provided with Pt comb-type interdigitated electrodes in N2 atmosphere. Scanning electron microscopy and x-ray photoelectron spectroscopy characterizations show respectively the occurrence of a mixed structure, composed of BP coarse aggregates dispersed on BP exfoliated few layer flakes bridging the electrodes, and a clear 2p doublet belonging to BP, which excludes the occurrence of surface oxidation. Room temperature electrical tests in dry air show a p-type response of multilayer BP with measured detection limits of 20 ppb and 10 ppm to NO2 and NH3 respectively. No response to CO and CO2 has been detected, while a slight but steady sensitivity to H2 has been recorded. The reported results confirm, on an experimental basis, what was previously theoretically predicted, demonstrating the promising sensing properties of exfoliated BP.

  17. Automobile Exhaust Pollution and Purification Methods

    OpenAIRE

    Tang, Dawei

    2014-01-01

    As we all know, the automobile gas exhaust pollution has become more and more severe at recent years. It influences both to the human beings health and to quality of environment. The purpose of this thesis is to find out what are the main components of the exhaust gases, and give a basic and effective way to solve the problem. In this thesis, first the danger of exhaust pollution and its components will be presented. Then the writer will give the general mechanism of automobile exhaust ...

  18. 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

  19. Reduced graphene oxide for room-temperature gas sensors

    Science.gov (United States)

    Lu, Ganhua; Ocola, Leonidas E.; Chen, Junhong

    2009-11-01

    We demonstrated high-performance gas sensors based on graphene oxide (GO) sheets partially reduced via low-temperature thermal treatments. Hydrophilic graphene oxide sheets uniformly suspended in water were first dispersed onto gold interdigitated electrodes. The partial reduction of the GO sheets was then achieved through low-temperature, multi-step annealing (100, 200, and 300 °C) or one-step heating (200 °C) of the device in argon flow at atmospheric pressure. The electrical conductance of GO was measured after each heating cycle to interpret the level of reduction. The thermally-reduced GO showed p-type semiconducting behavior in ambient conditions and was responsive to low-concentration NO2 and NH3 gases diluted in air at room temperature. The sensitivity can be attributed mainly to the electron transfer between the reduced GO and adsorbed gaseous molecules (NO2/NH3). Additionally, the contact between GO and the Au electrode is likely to contribute to the overall sensing response because of the adsorbates-induced Schottky barrier variation. A simplified model is used to explain the experimental observations.

  20. A highly efficient six-stroke internal combustion engine cycle with water injection for in-cylinder exhaust heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    Conklin, James C.; Szybist, James P. [Oak Ridge National Laboratory, 2360 Cherahala Blvd, Knoxville, TN 37932 (United States)

    2010-04-15

    A concept adding two strokes to the Otto or Diesel engine cycle to increase fuel efficiency is presented here. It can be thought of as a four-stroke Otto or Diesel cycle followed by a two-stroke heat recovery steam cycle. A partial exhaust event coupled with water injection adds an additional power stroke. Waste heat from two sources is effectively converted into usable work: engine coolant and exhaust gas. An ideal thermodynamics model of the exhaust gas compression, water injection and expansion was used to investigate this modification. By changing the exhaust valve closing timing during the exhaust stroke, the optimum amount of exhaust can be recompressed, maximizing the net mean effective pressure of the steam expansion stroke (MEP{sub steam}). The valve closing timing for maximum MEP{sub steam} is limited by either 1 bar or the dew point temperature of the expansion gas/moisture mixture when the exhaust valve opens. The range of MEP{sub steam} calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEP{sub combustion}) of naturally aspirated gasoline engines are up to 10 bar, thus this concept has the potential to significantly increase the engine efficiency and fuel economy. (author)

  1. Advances in High Temperature Gas Cooled Reactor Fuel Technology

    International Nuclear Information System (INIS)

    This publication reports on the results of a coordinated research project on advances in high temperature gas cooled reactor (HTGR) fuel technology and describes the findings of research activities on coated particle developments. These comprise two specific benchmark exercises with the application of HTGR fuel performance and fission product release codes, which helped compare the quality and validity of the computer models against experimental data. The project participants also examined techniques for fuel characterization and advanced quality assessment/quality control. The key exercise included a round-robin experimental study on the measurements of fuel kernel and particle coating properties of recent Korean, South African and US coated particle productions applying the respective qualification measures of each participating Member State. The summary report documents the results and conclusions achieved by the project and underlines the added value to contemporary knowledge on HTGR fuel.

  2. Medium-size high-temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    This report summarizes high-temperature gas-cooled reactor (HTGR) experience for the 40-MW(e) Peach Bottom Nuclear Generating Station of Philadelphia Electric Company and the 330-MW(e) Fort St. Vrain Nuclear Generating Station of the Public Service Company of Colorado. Both reactors are graphite moderated and helium cooled, operating at approx. 7600C (14000F) and using the uranium/thorium fuel cycle. The plants have demonstrated the inherent safety characteristics, the low activation of components, and the high efficiency associated with the HTGR concept. This experience has been translated into the conceptual design of a medium-sized 1170-MW(t) HTGR for generation of 450 MW of electric power. The concept incorporates inherent HTGR safety characteristics [a multiply redundant prestressed concrete reactor vessel (PCRV), a graphite core, and an inert single-phase coolant] and engineered safety features

  3. The Status of Marine Engine Exhaust Gas Scrubbing and Desulfurizing Technology and its Development Trend%船舶废气洗涤脱硫技术现状及发展趋势

    Institute of Scientific and Technical Information of China (English)

    周松; 李琤; 沈飞翔

    2014-01-01

    As marine engine exhaust gas emission limitation is becoming more and more stringent, the research state of marine engine exhaust gas scrubber is introduced in detail, and the tendency, economy and prospect of the application of marine scrubbers are analyzed. The research shows that the exhaust gas scrubber is a valid measure to meet IMO 2015 regulation of fuel sulphur content. Although the initial in-vestment of scrubber is large, the capital can be recovered in 1~4 years, and is expected to have wide application in marine auxiliary products market.%针对船舶排放控制日趋严格,介绍了国内外船舶动力装置废气洗涤脱硫技术的研究现状,并分析了其发展趋势、经济性和应用前景。研究表明,船舶废气洗涤技术是应对2015年IMO燃油含硫量限制的有效方法。洗涤系统虽然初投资较大,但成本可在1~4年内收回,具有广阔的市场前景。

  4. Roles of catalytic oxidation in control of vehicle exhaust emissions

    International Nuclear Information System (INIS)

    Catalytic oxidation was initially associated with the early development of catalysis and it subsequently became a part of many industrial processes, so it is not surprising it was used to remove hydrocarbons and CO when it became necessary to control these emissions from cars. Later NOx was reduced in a process involving reduction over a Pt/Rh catalyst followed by air injection in front of a Pt-based oxidation catalyst. If over-reduction of NO to NH3 took place, or if H2S was produced, it was important these undesirable species were converted to NOx and SOx in the catalytic oxidation stage. When exhaust gas composition could be kept stoichiometric hydrocarbons, CO and NOx were simultaneously converted over a single Pt/Rh three-way catalyst (TWC). With modern TWCs car tailpipe emissions can be exceptionally low. NO is not catalytically dissociated to O2 and N2 in the presence of O2, it can only be reduced to N2. Its control from lean-burn gasoline engines involves catalytic oxidation to NO2 and thence nitrate that is stored and periodically reduced to N2 by exhaust gas enrichment. This method is being modified for diesel engines. These engines produce soot, and filtration is being introduced to remove it. The exhaust temperature of heavy-duty diesels is sufficient (250-400oC) for NO to be catalytically oxidised to NO2 over an upstream platinum catalyst that smoothly oxidises soot in the filter. The exhaust gas temperature of passenger car diesels is too low for this to take place all of the time, so trapped soot is periodically burnt in O2 above 550oC. Catalytic oxidation of higher than normal amounts of hydrocarbon and CO over an upstream catalyst is used to give sufficient temperature for soot combustion with O2 to take place. (author)

  5. 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

  6. The determination of regulated and some unregulated exhaust gas components from ethanol blended diesel fuels in comparison with neat diesel and ethanol fuel

    International Nuclear Information System (INIS)

    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 NOx 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

  7. Metal sorbents for high temperature mercury capture from fuel gas

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Poulston; Evan J. Granite; Henry W. Pennline; Christina R. Myers; Dennis P. Stanko; Hugh Hamilton; Liz Rowsell; Andrew W.J. Smith; Thomas Ilkenhans; Wilson Chu [Johnson Matthey Technology Centre, Reading (United Kingdom)

    2007-07-01

    We have determined the effect of a pre-sulphiding treatment on the Hg removal capacities of Pt and Pd supported on alumina at a range of different metal loadings from 2 to 9wt% using Hg vapour in a simulated fuel gas feed. In the temperature range studied (204-288{sup o}C) Pd proved far superior to Pt for Hg removal and the sulphur pre-treatment led to a considerable increase in the Hg adsorption capacity. The Hg removal capacity for Pd increased with metal loading though decreased with sorbent temperature. A shift in the 2 Theta position of the Pd XRD diffraction peak from 82.1 to 79.5{sup o} after Hg adsorption at 204{sup o}C in the absence of a sulphur pre-treatment was consistent with the formation of a solid solution of Hg in Pd, with the sulphur pre-treatment the Pd related XRD peaks occur at even lower 2 Theta position suggesting a different Pd-Hg phase is formed. 5 refs., 1 tab.

  8. Thermal Hydraulics of the Very High Temperature Gas Cooled Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chang Oh; Eung Kim; Richard Schultz; Mike Patterson; Davie Petti

    2009-10-01

    The U.S Department of Energy (DOE) is conducting research on the Very High Temperature Reactor (VHTR) design concept for the Next Generation Nuclear Plant (NGNP) Project. The reactor design will be a graphite moderated, thermal neutron spectrum reactor that will produce electricity and hydrogen in a highly efficient manner. The NGNP reactor core will be either a prismatic graphite block type core or a pebble bed core. The NGNP will use very high-burnup, low-enriched uranium, TRISO-coated fuel, and have a projected plant design service life of 60 years. The VHTR concept is considered to be the nearest-term reactor design that has the capability to efficiently produce hydrogen. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during reactor core-accidents. The objectives of the NGNP Project are to: Demonstrate a full-scale prototype VHTR that is commercially licensed by the U.S. Nuclear Regulatory Commission, and Demonstrate safe and economical nuclear-assisted production of hydrogen and electricity. The DOE laboratories, led by the INL, perform research and development (R&D) that will be critical to the success of the NGNP, primarily in the areas of: • High temperature gas reactor fuels behavior • High temperature materials qualification • Design methods development and validation • Hydrogen production technologies • Energy conversion. This paper presents current R&D work that addresses fundamental thermal hydraulics issues that are relevant to a variety of possible NGNP designs.

  9. Thermal Hydraulics of the Very High Temperature Gas Cooled Reactor

    International Nuclear Information System (INIS)

    The U.S Department of Energy (DOE) is conducting research on the Very High Temperature Reactor (VHTR) design concept for the Next Generation Nuclear Plant (NGNP) Project. The reactor design will be a graphite moderated, thermal neutron spectrum reactor that will produce electricity and hydrogen in a highly efficient manner. The NGNP reactor core will be either a prismatic graphite block type core or a pebble bed core. The NGNP will use very high-burnup, low-enriched uranium, TRISO-coated fuel, and have a projected plant design service life of 60 years. The VHTR concept is considered to be the nearest-term reactor design that has the capability to efficiently produce hydrogen. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during reactor core-accidents. The objectives of the NGNP Project are to: Demonstrate a full-scale prototype VHTR that is commercially licensed by the U.S. Nuclear Regulatory Commission, and Demonstrate safe and economical nuclear-assisted production of hydrogen and electricity. The DOE laboratories, led by the INL, perform research and development (R and D) that will be critical to the success of the NGNP, primarily in the areas of: (1) High temperature gas reactor fuels behavior; (2) High temperature materials qualification; (3) Design methods development and validation; (4) Hydrogen production technologies; and (5) Energy conversion. This paper presents current R and D work that addresses fundamental thermal hydraulics issues that are relevant to a variety of possible NGNP designs

  10. Thermal hydraulics of the very high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    The Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy, is conducting research on the Very High Temperature Reactor (VHTR) design concept for the Next Generation Nuclear Plant (NGNP) Project. The reactor design will be a graphite moderated, thermal neutron spectrum reactor that will produce electricity and hydrogen in a highly efficient manner. The NGNP reactor core will be either a prismatic graphite block type core or a pebble bed core. The NGNP will use very high-burnup, low-enriched uranium, TRISO-coated fuel, and have a projected plant design service life of 60 years. The VHTR concept is considered to be the nearest-term reactor design that has the capability to efficiently produce hydrogen. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during reactor core-accidents. The objectives of the NGNP Project are to: Demonstrate a full-scale prototype VHTR that is commercially licensed by the U.S. Nuclear Regulatory Commission, and Demonstrate safe and economical nuclear-assisted production of hydrogen and electricity. The DOE laboratories, led by the INL, perform research and development (R and D) that will be critical to the success of the NGNP, primarily in the areas of: · High temperature gas reactor fuels behavior · High temperature materials qualification · Design methods development and validation · Hydrogen production technologies · Energy conversion. This paper presents current R and D work that addresses fundamental thermal hydraulics issues that are relevant to a variety of possible NGNP designs. (author)

  11. Lanthanide Catalysts for Conversion of Exhaust Gas from Compressed Natural Gas Automobiles%压缩天然气汽车稀土型尾气转化催化剂

    Institute of Scientific and Technical Information of China (English)

    姚如杰; 董新彬

    2004-01-01

    Aiming at improving the air quality, more and more automobiles with compressed natural gas (CNG) fuel are being used in some big cities now. The three way catalysts (TWC) for gasoline cars are not suitable for CNG cars. In the exhaust gases from CNG cars, the hydrocarbon is mainly methane, which is converted into carbon dioxide quite difficultly compared with other hydrocarbons. In this paper, a specially designed catalyst dosage was developed, which contained lanthanide oxides, transition element oxides and a minor part of noble metal oxides. The catalysts can reach a high conversion ratio for the exhaust pollutants above 700℃. More than 98.0 per cent of CH4 and CO in CNG engine exhaust gases can be converted into CO2 and H2O. At 1 000℃, the catalyst maintains a 99.0 per cent conversion ratio for CH4 and CO in 1.5 h, showing a high thermal stability. A resistance to sulfur oxides was also behaved.%压缩天然气(CNG)汽车因其良好的排放特性,正被越来越多的大型城市公交系统使用,但是汽油车辆用尾气净化催化剂对天然气汽车的主要烃类排放物甲烷转化效率低.针对天然气车辆排放物特点,设计了天然气汽车尾气净化催化剂,其成分包括稀土金属和过渡金属化合物、少量贵金属氧化物、结构稳定剂等.试验结果表明,在700℃以上,CO和CH4转化率达到98%以上,催化剂耐高温性能好,在1 000℃,1.5 h试验时间内HC和CO转化率达到99%,此外该催化剂具有一定的抗硫化物中毒能力.

  12. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    OpenAIRE

    Xiao-Liang Wang; Ming-Xu Zhang; Kun-Zhi Liu; Xi-Ming Sun

    2014-01-01

    We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs) condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the...

  13. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    Directory of Open Access Journals (Sweden)

    Xiao-Liang Wang

    2014-01-01

    Full Text Available We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the effectiveness of the stability criterion.

  14. Estimating the temperature of a catalytic converter

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T.T.-H.

    1994-11-02

    A method of estimating the temperature of a catalytic converter used in the exhaust system of an internal combustion engine is described. Heated exhaust gas oxygen (HEGO) sensors are placed upstream and downstream of the catalytic converter. The temperature of the catalytic converter shortly after start-up is measured by monitoring the resistance of the HEGO sensor's heating element. The downstream sensor is used for mixture control and to double check results of the upstream sensor. (UK)

  15. Study on Thermoelectric Generators Based on Exhaust Gas and Cryogenic Fuel for LNG Vehicles%面向 LNG 汽车的发动机排气与低温燃料温差发电器研究

    Institute of Scientific and Technical Information of China (English)

    郑江; 厉彦忠; 王春燕; 谭宏博

    2014-01-01

    To enhance the energy efficiency in the liquefied natural gas (LNG) vehicles, thermoelectric generator (TEG) is suggested in recovering the waste heat of the exhaust gas (EG) and the cold energy of the LNG.The TEGs here get higher efficiency than conventional ones, for they work with heat sinks at cryogenic temperatures and there are large temperature differences between EG and LNG.Based on the analyzing of the typical fuel system in the small LNG vehicles, two recovery systems for the LNG vehicles are proposed and the correla_tive parameters of systems are calculated and analyzed.The generation efficiency of TEGs is calculated and the recovery power of each sys_tem is analyzed.It is concluded that the output power of the vaporizer system is larger than that of the self_warming system; TEG with opti_mized multi_layer material brings larger output power than that with single_layer material for both systems.%为实现液化天然气(LNG)汽车的节能,提出了利用温差发电器(TEG)回收发动机排气(EG)的废热和低温燃料的冷能。指出了基于冷源所在的低温区,以及 EG 与 LNG 之间的大温差这两个特点,TEG 的热电转换效率会高于常规。基于对小型 LNG汽车中典型燃料系统的分析,设计了进行能量回收的两种系统流程,计算了其中各状态点的参数﹑及各换热器中布置温差发电器后的热电转换效率,得到了系统总的回收功率。结果表明,汽化器系统的回收功率大于自复温系统;在两种系统中,合理选取多种材料相较于仅用单种材料,TEG 的回收功率更大。

  16. Heat Exhaustion, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Heat Exhaustion, First Aid A A A Heat exhaustion signs and symptoms ... specific to the other stages of heat illness. First Aid Guide Use a combination of the following measures ...

  17. Effect of Temperature on Gas Hold—up in Aerated Stirred Tanks

    Institute of Scientific and Technical Information of China (English)

    高正明; 施力田

    2003-01-01

    Gas holdups in ambient gassed and hot sparged systems with multiple modern impellers and the effect of temperature on gas holdup are reported,The operating temperature has a great impact on gas holdup though the gas dispersion regime in the hot sparged system is similar to the ambient gassed condition,The gas holdup under the elevated temperature and the ambient gassed operation is successfully correlated.With the sarme total gas flow rate and power input,the gas holdup in the hot sparged system(say near the boiling point)is only about half of that in the ambient system ,The results imply that almost all existing hot sparged reactors have been designed on the basis of incorrect estimates of the gas holdup during operation.

  18. Integration of a molten carbonate fuel cell with a direct exhaust absorption chiller

    Energy Technology Data Exchange (ETDEWEB)

    Margalef, Pere; Samuelsen, Scott [National Fuel Cell Research Center (NFCRC), University of California, Irvine, CA 92697-3550 (United States)

    2010-09-01

    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

  19. Multiphysics methods development for high temperature gas reactor analysis

    Science.gov (United States)

    Seker, Volkan

    Multiphysics computational methods were developed to perform design and safety analysis of the next generation Pebble Bed High Temperature Gas Cooled Reactors. A suite of code modules was developed to solve the coupled thermal-hydraulics and neutronics field equations. The thermal-hydraulics module is based on the three dimensional solution of the mass, momentum and energy equations in cylindrical coordinates within the framework of the porous media method. The neutronics module is a part of the PARCS (Purdue Advanced Reactor Core Simulator) code and provides a fine mesh finite difference solution of the neutron diffusion equation in three dimensional cylindrical coordinates. Coupling of the two modules was performed by mapping the solution variables from one module to the other. Mapping is performed automatically in the code system by the use of a common material mesh in both modules. The standalone validation of the thermal-hydraulics module was performed with several cases of the SANA experiment and the standalone thermal-hydraulics exercise of the PBMR-400 benchmark problem. The standalone neutronics module was validated by performing the relevant exercises of the PBMR-268 and PBMR-400 benchmark problems. Additionally, the validation of the coupled code system was performed by analyzing several steady state and transient cases of the OECD/NEA PBMR-400 benchmark problem.

  20. High temperature strain gage technology for gas turbine engines

    Science.gov (United States)

    Fichtel, Edward J.; McDaniel, Amos D.

    1994-08-01

    This report summarizes the results of a six month study that addressed specific issues to transfer the Pd-13Cr static strain sensor to a gas turbine engine environment. The application issues that were addressed include: (1) evaluation of a miniature, variable potentiometer for use as the ballast resistor, in conjunction with a conventional strain gage signal conditioning unit; (2) evaluation of a metal sheathed, platinum conductor leadwire assembly for use with the three-wire sensor; and (3) subjecting the sensor to dynamic strain cyclic testing to determine fatigue characteristics. Results indicate a useful static strain gage system at all temperature levels up to 1350 F. The fatigue characteristics also appear to be very promising, indicating a potential use in dynamic strain measurement applications. The procedure, set-up, and data for all tests are presented in this report. This report also discusses the specific strain gage installation technique for the Pd-13Cr gage because of its potential impact on the quality of the output data.

  1. Exhaust emission control and diagnostics

    Science.gov (United States)

    Mazur, Christopher John; Upadhyay, Devesh

    2006-11-14

    A diesel engine emission control system uses an upstream oxidation catalyst and a downstream SCR catalyst to reduce NOx in a lean exhaust gas environment. The engine and upstream oxidation catalyst are configured to provide approximately a 1:1 ratio of NO to NO2 entering the downstream catalyst. In this way, the downstream catalyst is insensitive to sulfur contamination, and also has improved overall catalyst NOx conversion efficiency. Degradation of the system is determined when the ratio provided is no longer near the desired 1:1 ratio. This condition is detected using measurements of engine operating conditions such as from a NOx sensor located downstream of the catalysts. Finally, control action to adjust an injected amount of reductant in the exhaust gas based on the actual NO to NO2 ratio upstream of the SCR catalyst and downstream of the oxidation catalyst.

  2. Gas-Liquid Mass Transfer Characteristics in a Gas-Liquid-Solid Bubble Column under Elevated Pressure and Temperature

    Institute of Scientific and Technical Information of China (English)

    Haibo Jin; Suohe Yang; Guangxiang He; Delin Liu; Zemin Tong; Jianhua Zhu

    2014-01-01

    abstract The volumetric mass transfer coefficient kLa of gases (H2, CO, CO2) and mass transfer coefficient kL on liquid par-affin side were studied using the dynamic absorption method in slurry bubble column reactors under elevated temperature and elevated pressure. Meanwhile, gas-holdup and gas-liquid interfacial area a were obtained. The effects of temperature, pressure, superficial gas velocity and solid concentration on the mass transfer coeffi-cient were discussed. Experimental results show that the gas-liquid volumetric mass transfer coefficient kLa and interfacial area a increased with the increase of pressure, temperature, and superficial gas velocity, and decreased with the slurry concentration. The mass transfer coefficient kL increased with increasing superficial gas velocity and temperature and decreased with higher slurry concentration, while it changed slightly with pressure. Ac-cording to analysis of experimental data, an empirical correlation is obtained to calculate the values of kLa for H2 (CO, CO2) in the gas-paraffin-quartz system in a bubble column under elevated temperature and elevated pressure.

  3. Numerical Modeling of Exhaust Smoke Dispersion for a Generic Frigate and Comparisons with Experiments

    Institute of Scientific and Technical Information of China (English)

    Selma Ergin; Erin Dobrucal

    2014-01-01

    The exhaust smoke dispersion for a generic frigate is investigated numerically through the numerical solution of the governing fluid flow, energy, species and turbulence equations. The main objective of this work is to obtain the effects of the yaw angle, velocity ratio and buoyancy on the dispersion of the exhaust smoke. The numerical method is based on the fully conserved control-volume representation of the fully elliptic Navier-Stokes equations. Turbulence is modeled using a two-equation (k-ε) model. The flow visualization tests using a 1/100 scale model of the frigate in the wind tunnel were also carried out to determine the exhaust plume path and to validate the computational results. The results show that down wash phenomena occurs for the yaw angles between ψ=10° and 20°. The results with different exhaust gas temperatures show that the buoyancy effect increases with the increasing of the exhaust gas temperature. However, its effect on the plume rise is less significant in comparison with its momentum. A good agreement between the predictions and experiment results is obtained.

  4. Numerical modeling of exhaust smoke dispersion for a generic frigate and comparisons with experiments

    Science.gov (United States)

    Ergin, Selma; Dobrucalı, Erinç

    2014-06-01

    The exhaust smoke dispersion for a generic frigate is investigated numerically through the numerical solution of the governing fluid flow, energy, species and turbulence equations. The main objective of this work is to obtain the effects of the yaw angle, velocity ratio and buoyancy on the dispersion of the exhaust smoke. The numerical method is based on the fully conserved control-volume representation of the fully elliptic Navier-Stokes equations. Turbulence is modeled using a two-equation ( k- ɛ) model. The flow visualization tests using a 1/100 scale model of the frigate in the wind tunnel were also carried out to determine the exhaust plume path and to validate the computational results. The results show that down wash phenomena occurs for the yaw angles between ψ =10° and 20°. The results with different exhaust gas temperatures show that the buoyancy effect increases with the increasing of the exhaust gas temperature. However, its effect on the plume rise is less significant in comparison with its momentum. A good agreement between the predictions and experiment results is obtained.

  5. An Annular Mechanical Temperature Compensation Structure for Gas-Sealed Capacitive Pressure Sensor

    OpenAIRE

    Kohei Higuchi; Yonggang Jiang; Kazusuke Maenaka; Hidekuni Takao; Xiuchun Hao

    2012-01-01

    A novel gas-sealed capacitive pressure sensor with a temperature compensation structure is reported. The pressure sensor is sealed by Au-Au diffusion bonding under a nitrogen ambient with a pressure of 100 kPa and integrated with a platinum resistor-based temperature sensor for human activity monitoring applications. The capacitance-pressure and capacitance-temperature characteristics of the gas-sealed capacitive pressure sensor without temperature compensation structure are calculated. It is...

  6. Low-Temperature Photochemically Activated Amorphous Indium-Gallium-Zinc Oxide for Highly Stable Room-Temperature Gas Sensors.

    Science.gov (United States)

    Jaisutti, Rawat; Kim, Jaeyoung; Park, Sung Kyu; Kim, Yong-Hoon

    2016-08-10

    We report on highly stable amorphous indium-gallium-zinc oxide (IGZO) gas sensors for ultraviolet (UV)-activated room-temperature detection of volatile organic compounds (VOCs). The IGZO sensors fabricated by a low-temperature photochemical activation process and exhibiting two orders higher photocurrent compared to conventional zinc oxide sensors, allowed high gas sensitivity against various VOCs even at room temperature. From a systematic analysis, it was found that by increasing the UV intensity, the gas sensitivity, response time, and recovery behavior of an IGZO sensor were strongly enhanced. In particular, under an UV intensity of 30 mW cm(-2), the IGZO sensor exhibited gas sensitivity, response time and recovery time of 37%, 37 and 53 s, respectively, against 750 ppm concentration of acetone gas. Moreover, the IGZO gas sensor had an excellent long-term stability showing around 6% variation in gas sensitivity over 70 days. These results strongly support a conclusion that a low-temperature solution-processed amorphous IGZO film can serve as a good candidate for room-temperature VOCs sensors for emerging wearable electronics. PMID:27430635

  7. The gas corrosion of the cobalt base clad layer at elevated temperature

    Directory of Open Access Journals (Sweden)

    H. Smolenska

    2006-08-01

    Full Text Available Purpose: Purpose of this paper is to evaluate the microstructural and mechanical properties evolution of thelaser and PTA clad layers made of the powder containing cobalt after oxidation in air (750°C, 200 hours andcorrosion in exhaust gases (700°C, two month.Design/methodology/approach: The layers were made by cladding technique. Cladding was conducted witha high power diode laser HDPL ROFIN SINAR DL 020 and Plasma Transformed Arc method. The subsequenttracks were overlapped by 30÷40%. The performance of the hardfaced materials were evaluated by microstructure(optical and scanning electron microscope SEM, chemical analysis and micro hardness measurements.Findings: After heat treatment the microstructure of the clad layers did not change much, neither on the top partnor in the clad/steel interface. However the oxide layer on the surface is observed. The EDS analyze revile thecomposition of this scale which consisted generally of chromium and iron oxides. The semi-quantitative chemicalanalysis (EDS of the dendritic regions and micro regions confirms changes in chemical contents before and afteroxidation and after corrosion in exhaust gases. The oxidation at temperature 750°C for 200 hours in air and fortwo month in exhaust gases did not influence on the morphology of the clad layers neither on the top part nor inthe clad/steel interface. However changes in chemical composition were observed. On the surface of both sort ofclads the oxide layers were observed. These sorts of layers are resistant for the hot exhausted gases.Research limitations/implications: During the future research kinetic analyze of high temperature corrosionshould be done also for different temperature and times of the process.Practical implications: The layers were designed as a method to prolong service time for the ship engineexhausted valve.Originality/value: The chemical composition of the powder was new one. Also using the laser claddingtechnique for ship engine parts

  8. Determination of an instability temperature for alloys in the cooling gas of a high temperature reactor

    International Nuclear Information System (INIS)

    High temperature alloys designed to be used for components in the primary circuit of a helium cooled high temperature nuclear reactor show massive CO production above a certain temperature, called the instability temperature T/sub i/, which increases with increasing partial pressure of CO in the cooling gas. At p/sub CO/ = 15 microbar, T/sub i/ lies between 900 and 950 degrees C for the four alloys under investigation: T/sub i/ is lowest for the iron base alloy Incoloy 800 H and increases for the nickel base alloys in the order Inconel 617, HDA 230 and Nimonic 86. Measurements of T/sub i/ made at 3 different laboratories were compared and shown to agree for p/sub CO/25 microbar, compatible with CO production by a reaction of Cr2O3 with carbides. Some measurements of T/sub i/ on HDA 230 and Nimonic 86 were performed in the course of simulated reactor disturbances. They showed that the oxide layer looses its protective properties above T/sub i/. A highlight of the examinations was the detection of eta-carbides (M6C) with unusual properties. M6C is the only type of carbide occuring in HDA 230. An eta-carbide with a lattice constant of 1088.8 pm had developed at the surface of Nimonic 86 during pre-oxidation before the disturbance simulation. Its composition is estimated at Ni3SiMo2C. Eta-carbides containing Si and especially eta-carbides with lattice constants as low as 1088.8 pm have been described only rarely until now. (author)

  9. Coated particle fuel for high temperature gas cooled reactors

    International Nuclear Information System (INIS)

    for process heat/hydrogen generation applications with 950 .deg. C outlet temperatures. There is a clear set of standards for modern high quality fuel in terms of low levels of heavy metal contamination, manufacture-induced particle defects during fuel body and fuel element making, irradiation/accident induced particle failures and limits on fission product release from intact particles. While gas-cooled reactor design is still open-ended with blocks for the prismatic and spherical fuel elements for the pebble-bed design, there is near worldwide agreement on high quality fuel: a 500 μm diameter UO2 kernel of 10% enrichment is surrounded by a 100 μm thick sacrificial buffer layer to be followed by a dense inner pyrocarbon layer, a high quality silicon carbide layer of 35 μm thickness and theoretical density and another outer pyrocarbon layer. Good performance has been demonstrated both under operational and under accident conditions, i.e. to 10% FIMA and maximum 1600 .deg. C afterwards. And it is the wide-ranging demonstration experience that makes this particle superior. Recommendations are made for further work: 1. Generation of data for presently manufactured materials, e.g. SiC strength and strength distribution, PyC creep and shrinkage and many more material data sets. 2. Renewed start of irradiation and accident testing of modern coated particle fuel. 3. Analysis of existing and newly created data with a view to demonstrate satisfactory performance at burnups beyond 10% FIMA and complete fission product retention even in accidents that go beyond 1600 .deg. C for a short period of time. This work should proceed at both national and international level

  10. THE INTEGRATION OF PROCESS HEAT APPLICATIONS TO HIGH TEMPERATURE GAS REACTORS

    Energy Technology Data Exchange (ETDEWEB)

    Michael G. McKellar

    2011-11-01

    A high temperature gas reactor, HTGR, can produce industrial process steam, high-temperature heat-transfer gases, and/or electricity. In conventional industrial processes, these products are generated by the combustion of fossil fuels such as coal and natural gas, resulting in significant emissions of greenhouse gases such as carbon dioxide. Heat or electricity produced in an HTGR could be used to supply process heat or electricity to conventional processes without generating any greenhouse gases. Process heat from a reactor needs to be transported by a gas to the industrial process. Two such gases were considered in this study: helium and steam. For this analysis, it was assumed that steam was delivered at 17 MPa and 540 C and helium was delivered at 7 MPa and at a variety of temperatures. The temperature of the gas returning from the industrial process and going to the HTGR must be within certain temperature ranges to maintain the correct reactor inlet temperature for a particular reactor outlet temperature. The returning gas may be below the reactor inlet temperature, ROT, but not above. The optimal return temperature produces the maximum process heat gas flow rate. For steam, the delivered pressure sets an optimal reactor outlet temperature based on the condensation temperature of the steam. ROTs greater than 769.7 C produce no additional advantage for the production of steam.

  11. High temperature heat exchanger studies for applications to gas turbines

    Science.gov (United States)

    Min, June Kee; Jeong, Ji Hwan; Ha, Man Yeong; Kim, Kui Soon

    2009-12-01

    Growing demand for environmentally friendly aero gas-turbine engines with lower emissions and improved specific fuel consumption can be met by incorporating heat exchangers into gas turbines. Relevant researches in such areas as the design of a heat exchanger matrix, materials selection, manufacturing technology, and optimization by a variety of researchers have been reviewed in this paper. Based on results reported in previous studies, potential heat exchanger designs for an aero gas turbine recuperator, intercooler, and cooling-air cooler are suggested.

  12. IDENTIFICATION OF DYNAMIC CHARACTERISTICS OF AIRCRAFT GAS TEMPERATURE SENSORS

    Directory of Open Access Journals (Sweden)

    A. F. Sabitov

    2016-01-01

    Full Text Available The estimation of dynamic behavior of aircraft gas temperature sensors (GTS has to be done only in certified air installations and be based on recorded experimental transient response in accordance with the departmental standard. Experimental transient response has hindrances of different nature and can influence the accuracy of identification of dynamic behaviour of GTS. We suggested a new method to increase the accuracy of identification of dynamic behavior of GTS. The method is based on the use of amplitude spectrum of signal composed of experimental transient response. Shaped signal is an impulse decaying signal satisfying a Dirichlet condition and Fourier transform can apply to it to get amplitude spectrum. We worked out the relation between amplitude spectrum of shaped signals and time constant of dynamic behaviour for three mathematical models of GTS. The research showed that the information about dynamic behaviour of standard aircraft GTS is located in LF part of amplitude spectrum in the range of 0 to 1 rad/s and to 3 rad/s. The study revealed that hindrance in the transient response at frequency higher than 3 rad/s did not influence the accuracy of results if to use LF part of amplitude spectrum for the identification of dynamic behaviour of GTS. The amplitude spectrum of shaped signal can be estimated by measuring equipment like LF spectrum analyzer or calculated by software package with the function of fast Fourier transform. The value of time constant of certain mathematical model of GTS can be realized with the help of regression analysis or the use of embedded resources of different data processing systems. Thus, the method gives an opportunity to increase the accuracy of identification of dynamic behavior of GTS. 

  13. Proliferation resistance assessment of high temperature gas reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chikamatsu N, M. A. [Instituto Tecnologico y de Estudios Superiores de Monterrey, Campus Santa Fe, Av. Carlos Lazo No. 100, Santa Fe, 01389 Mexico D. F. (Mexico); Puente E, F., E-mail: midori.chika@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    The Generation IV International Forum has established different objectives for the new generation of reactors to accomplish. These objectives are focused on sustain ability, safety, economics and proliferation resistance. This paper is focused on how the proliferation resistance of the High Temperature Gas Reactors (HTGR) is assessed and the advantages that these reactors present currently. In this paper, the focus will be on explaining why such reactors, HTGR, can achieve the goals established by the GIF and can present a viable option in terms of proliferation resistance, which is an issue of great importance in the field of nuclear energy generation. The reason why the HTGR are being targeted in this writing is that these reactors are versatile, and present different options from modular reactors to reactors with the same size as the ones that are being operated today. Besides their versatility, the HTGR has designed features that might improve on the overall sustain ability of the nuclear reactors. This is because the type of safety features and materials that are used open up options for industrial processes to be carried out; cogeneration for instance. There is a small section that mentions how HTGR s are being developed in the international sector in order to present the current world view in this type of technology and the further developments that are being sought. For the proliferation resistance section, the focus is on both the intrinsic and the extrinsic features of the nuclear systems. The paper presents a comparison between the features of Light Water Reactors (LWR) and the HTGR in order to be able to properly compare the most used technology today and one that is gaining international interest. (Author)

  14. Functional Integral Approach to the Transition Temperature of Attractive Interacting Bose Gas in Traps

    Institute of Scientific and Technical Information of China (English)

    HU Guang-Xi; DAI Xian-Xi

    2004-01-01

    The functional integral approach (FIA) is introduced to study the transition temperature of an imperfect Bose gas in traps.An interacting model in quantum statistical mechanics is presented.With the model we study a Bose gas with attractive interaction trapped in an external potential.We obtain the result that the transition temperature of a trapped Bose gas will slightly shift upwards owing to the attractive interacting force.Successful application of the FIA to Bose systems is demonstrated.

  15. 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.

  16. Scaling Studies for High Temperature Test Facility and Modular High Temperature Gas-Cooled Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Richard R. Schult; Paul D. Bayless; Richard W. Johnson; James R. Wolf; Brian Woods

    2012-02-01

    The Oregon State University (OSU) High Temperature Test Facility (HTTF) is an integral experimental facility that will be constructed on the OSU campus in Corvallis, Oregon. The HTTF project was initiated, by the U.S. Nuclear Regulatory Commission (NRC), on September 5, 2008 as Task 4 of the 5-year High Temperature Gas Reactor Cooperative Agreement via NRC Contract 04-08-138. Until August, 2010, when a DOE contract was initiated to fund additional capabilities for the HTTF project, all of the funding support for the HTTF was provided by the NRC via their cooperative agreement. The U.S. Department of Energy (DOE) began their involvement with the HTTF project in late 2009 via the Next Generation Nuclear Plant (NGNP) project. Because the NRC's interests in HTTF experiments were only centered on the depressurized conduction cooldown (DCC) scenario, NGNP involvement focused on expanding the experimental envelope of the HTTF to include steady-state operations and also the pressurized conduction cooldown (PCC).

  17. A low-temperature ZnO nanowire ethanol gas sensor prepared on plastic substrate

    Science.gov (United States)

    Lin, Chih-Hung; Chang, Shoou-Jinn; Hsueh, Ting-Jen

    2016-09-01

    In this work, a low-temperature ZnO nanowire ethanol gas sensor was prepared on plastic substrate. The operating temperature of the ZnO nanowire ethanol gas sensor was reduced to room temperature using ultraviolet illumination. The experimental results indicate a favorable sensor response at low temperature, with the best response at 60 °C. The results also reveal that the ZnO nanowire ethanol gas sensor can be easily integrated into portable products, whose waste heat can improve sensor response and achieve energy savings, while energy consumption can be further reduced by solar irradiation.

  18. Ammonia Gas Detection by Tannic Acid Functionalized and Reduced Graphene Oxide at Room Temperature

    OpenAIRE

    Sweejiang Yoo; Xin Li; Yuan Wu; Weihua Liu; Xiaoli Wang; Wenhui Yi

    2014-01-01

    Reduced graphene oxide (rGO) based chemiresistor gas sensor has received much attention in gas sensing for high sensitivity, room temperature operation, and reversible. Here, for the first time, we present a promising chemiresistor for ammonia gas detection based on tannic acid (TA) functionalized and reduced graphene oxide (rGOTA functionalized). Green reductant of TA plays a major role in both reducing process and enhancing the gas sensing properties of rGOTA functionalized. Our results sho...

  19. Silicon carbide-based hydrogen gas sensors for high-temperature applications.

    Science.gov (United States)

    Kim, Seongjeen; Choi, Jehoon; Jung, Minsoo; Joo, Sungjae; Kim, Sangchoel

    2013-01-01

    We investigated SiC-based hydrogen gas sensors with metal-insulator-semiconductor (MIS) structure for high temperature process monitoring and leak detection applications in fields such as the automotive, chemical and petroleum industries. In this work, a thin tantalum oxide (Ta2O5) layer was exploited with the purpose of sensitivity improvement, because tantalum oxide has good stability at high temperature with high permeability for hydrogen gas. Silicon carbide (SiC) was used as a substrate for high-temperature applications. We fabricated Pd/Ta2O5/SiC-based hydrogen gas sensors, and the dependence of their I-V characteristics and capacitance response properties on hydrogen concentrations were analyzed in the temperature range from room temperature to 500 °C. According to the results, our sensor shows promising performance for hydrogen gas detection at high temperatures. PMID:24113685

  20. Research on Diagnosis of Gas-Liquid Detonation Exhaust Based on Double Optical Path Absortion Spectroscopy Technique%基于双光路吸收光谱技术的气液两相爆轰燃气诊断技术研究

    Institute of Scientific and Technical Information of China (English)

    吕晓静; 李宁; 翁春生

    2014-01-01

    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 spec-troscopy technique combined with double optical path cross-correlation algorithm ,the article raises the diagnosis method to real-ize the on-line testing of detonation exhaust velocity ,temperature and H2 O 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 H2 O absorption lines of 1343nm with a high frequency of 50 kHz ,the on-line detection of gas-liquid pulse detonation exhaust is realized .The re-sults 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 un-der 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 · 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 .H2 O gas concentration changes between 0~7% during detonation under experi-mental conditions .The research can provide measurement data for the detonation process diagnosis and analysis ,which is of sig-nificance to advance the detonation mechanism research and promote the research of pulse detonation engine control technology .%对爆轰燃气准确有效地检测可以为探索爆轰形成机理以及提升爆轰发动机工作效率提供数据支撑。提出了基于可调谐半导体激光吸收光谱技术结合双光路互相关算法

  1. Developments in advanced high temperature disc and blade materials for aero-engine gas turbine applications

    OpenAIRE

    Everitt, S

    2012-01-01

    The research carried out as part of this EngD is aimed at understanding the high temperature materials used in modern gas turbine applications and providing QinetiQ with the information required to assess component performance in new propulsion systems. Performance gains are achieved through increased turbine gas temperatures which lead to hotter turbine disc rims and blades. The work has focussed on two key areas: (1) Disc Alloy Assessment of High Temperature Properties; and (2) Thermal Barr...

  2. TRISO-Coated Fuel Processing to Support High Temperature Gas-Cooled Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Del Cul, G.D.

    2002-10-01

    The initial objective of the work described herein was to identify potential methods and technologies needed to disassemble and dissolve graphite-encapsulated, ceramic-coated gas-cooled-reactor spent fuels so that the oxide fuel components can be separated by means of chemical processing. The purpose of this processing is to recover (1) unburned fuel for recycle, (2) long-lived actinides and fission products for transmutation, and (3) other fission products for disposal in acceptable waste forms. Follow-on objectives were to identify and select the most promising candidate flow sheets for experimental evaluation and demonstration and to address the needs to reduce technical risks of the selected technologies. High-temperature gas-cooled reactors (HTGRs) may be deployed in the next -20 years to (1) enable the use of highly efficient gas turbines for producing electricity and (2) provide high-temperature process heat for use in chemical processes, such as the production of hydrogen for use as clean-burning transportation fuel. Also, HTGR fuels are capable of significantly higher burn-up than light-water-reactor (LWR) fuels or fast-reactor (FR) fuels; thus, the HTGR fuels can be used efficiently for transmutation of fissile materials and long-lived actinides and fission products, thereby reducing the inventory of such hazardous and proliferation-prone materials. The ''deep-burn'' concept, described in this report, is an example of this capability. Processing of spent graphite-encapsulated, ceramic-coated fuels presents challenges different from those of processing spent LWR fuels. LWR fuels are processed commercially in Europe and Japan; however, similar infrastructure is not available for processing of the HTGR fuels. Laboratory studies on the processing of HTGR fuels were performed in the United States in the 1960s and 1970s, but no engineering-scale processes were demonstrated. Currently, new regulations concerning emissions will impact the

  3. High Temperature Gas Cooled Reactor Fuels and Materials

    International Nuclear Information System (INIS)

    At the third annual meeting of the technical working group on Nuclear Fuel Cycle Options and Spent Fuel Management (TWG-NFCO), held in Vienna, in 2004, it was suggested 'to develop manuals/handbooks and best practice documents for use in training and education in coated particle fuel technology' in the IAEA's Programme for the year 2006-2007. In the context of supporting interested Member States, the activity to develop a handbook for use in the 'education and training' of a new generation of scientists and engineers on coated particle fuel technology was undertaken. To make aware of the role of nuclear science education and training in all Member States to enhance their capacity to develop innovative technologies for sustainable nuclear energy is of paramount importance to the IAEA Significant efforts are underway in several Member States to develop high temperature gas cooled reactors (HTGR) based on either pebble bed or prismatic designs. All these reactors are primarily fuelled by TRISO (tri iso-structural) coated particles. The aim however is to build future nuclear fuel cycles in concert with the aim of the Generation IV International Forum and includes nuclear reactor applications for process heat, hydrogen production and electricity generation. Moreover, developmental work is ongoing and focuses on the burning of weapon-grade plutonium including civil plutonium and other transuranic elements using the 'deep-burn concept' or 'inert matrix fuels', especially in HTGR systems in the form of coated particle fuels. The document will serve as the primary resource materials for 'education and training' in the area of advanced fuels forming the building blocks for future development in the interested Member States. This document broadly covers several aspects of coated particle fuel technology, namely: manufacture of coated particles, compacts and elements; design-basis; quality assurance/quality control and characterization techniques; fuel irradiations; fuel

  4. Analysis of passive residual heat removal system of modular high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The passive residual heat removal system plays an important role for the inherent safety of high temperature gas-cooled reactor (HTGR). The thermal hydraulic calculation method for the residual heat removal system of HTGR was introduced. The operating temperatures of the residual heat removal system at different residual heat powers and different environmental temperatures were calculated. The containment concrete temperature was numerically simulated. The results show that the highest concrete temperature is acceptable. (authors)

  5. Influence of the Gas Mixture Ratio on the Correlations Between the Excimer XeCl* Emission and the Sealed Gas Temperature in Dielectric Barrier Discharge Lamps

    Institute of Scientific and Technical Information of China (English)

    徐金洲; 梁荣庆; 任兆杏

    2002-01-01

    For dielectric barrier discharge lamps filled with various gas mixture ratios, the correlations between the excimer XeCl* emission and the sealed gas temperature have been founded, and a qualitative explication is presented. For gas mixture with chlorine larger than 3%, the emission intensity increases with the sealed gas temperature, while with chlorine about 2%, the emission intensity decreases with the increase in the gas temperature, and could be improved by cooling water. However, if chlorine is less than 1.5%, the discharge appears to be a mixture mode with filaments distributed in a diffused glow-like discharge, and the UV emission is independent on the gas temperature.

  6. Temperature induced decay of persistent currents in superfluid ultracold gas

    CERN Document Server

    Kumar, Avinash; Jendrzejewski, Fred; Campbell, Gretchen K

    2016-01-01

    We study how temperature affects the lifetime of a quantized, persistent current state in a toroidal Bose-Einstein condensate (BEC). When the temperature is increased, we find a decrease in the persistent current lifetime. Comparing our measured decay rates to simple models of thermal activation and quantum tunneling, we do not find agreement. The measured critical velocity is also found to depend strongly on temperature, approaching the zero temperature mean-field solution as the temperature is decreased. This indicates that an appropriate definition of critical velocity must incorporate the role of thermal fluctuations, something not explicitly contained in traditional theories.

  7. The effect of metal salts on quantification of elemental and organic carbon in diesel exhaust particles using thermal-optical evolved gas analysis

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2010-07-01

    Full Text Available Thermal-optical evolved gas analysis (TOEGA is a conventional method for classifying carbonaceous aerosols as organic carbon (OC and elemental carbon (EC. Its main source of uncertainty arises from accounting for pyrolyzed OC (char, which has similar behavior to the EC originally present on the filter. Sample composition can also cause error, at least partly by complicating the charred carbon correction. In this study, lab generated metal salt particles, including alkali (NaCl, KCl, Na2SO4, alkaline-earth (MgCl2, CaCl2 and transition metal salts (CuCl2, FeCl2, FeCl3, CuCl, ZnCl2, MnCl2, CuSO4, Fe2(SO43, were deposited on a layer of diesel particles to investigate their effect on EC and OC quantification with TOEGA. Measurements show that metals reduce the oxidation temperature of EC and enhance the charring of OC. The split point used to determine classification of EC vs. OC is more dependent on changes in EC oxidation temperature than it was on charring. The resulting EC/OC ratio is reduced by 0–80% in the presence of most of the salts, although some metal salts increased reported EC/OC at low metal to carbon ratios. In general, transition metals are more active than alkali and alkaline-earth metals; copper is the most active. Copper and iron chlorides are more active than sulfates. The melting point of metal salts is strongly correlated with the increase of OC charring, but not with the reduction of EC oxidation temperature. Other chemistry, such as redox reactions, may affect the EC oxidation. A brief discussion of possible catalytic mechanisms for the metals is provided.

  8. Heat Recovery From Tail Gas Incineration To Generate Power

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, Tarek

    2010-09-15

    Many industrial processes result in tail gas wastes that must be flared or incinerated to abide with environmental guidelines. Tail gas incineration occurs in several chemical processes resulting in high-temperature exhaust gas that simply go to the stack, thus wasting all that valuable heat! This paper discusses useful heat recovery and electric power generation utilizing available heat in exhaust gas from tail gas incinerators. This heat will be recovered in a waste-heat recovery boiler that will produce superheated steam to expand in a steam turbine to generate power. A detailed cost estimate is presented.

  9. Analysis of characteristics of different working fluids for gas turbine cycle with high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Gas turbine cycle with high temperature gas-cooled reactor is the main direction of nuclear energy generation, which is with the advantages in terms of the safety and economy. The thermal and physical properties of helium, nitrogen, carbon dioxide and the mixtures were compared and analyzed in this paper. Further more, the heat transfer coefficient, pressure loss and the stage number of turbo-machines have been also compared. Results indicate that taking the mixture of helium and carbon dioxide as the working fluid of gas turbine cycle with high temperature gas-cooled reactor can not only improve the heat transfer coefficient and decrease the stage number of turbo-machinery, but also can limit the pressure loss to a certain level. (authors)

  10. Catalytic converter heating by reversible chemical reaction of CaO/Ca(OH)2. Simulation study of exhaust emission reduction with prototype heater; CaO/Ca(OH)2 kagyaku hannonetsu ni yoru sangen shokubai kanetsu hoshiki no kento. Prototype sochi no haishutsu gas joka seino simulation

    Energy Technology Data Exchange (ETDEWEB)

    Katashiba, H.; Kimura, H. [Mitsubishi Electric Corp., Tokyo (Japan); Morita, S. [Osaka City University, Osaka (Japan). Faculty of Engineering

    1998-07-25

    Rapid activation of three-way catalyst is very effective to reduce harmful substances in exhaust gas. For heating the catalyst of a car, feasibility study of CaO/Ca(OH)2 reversible exothermic reaction has been done. In this paper, experimental results of prototype heater with exothermic hydration and dehydration reaction are described. Furthermore, the performance of exhaust emission reduction with the prototype heater and Ca(OH)2 dehydration are estimated by simulation study. It is predicted that the prototype heater reduces unburned exhaust emission by 37% in LA-4 test cycle simulation. 6 refs., 5 figs.

  11. Local Exhaust Ventilation

    DEFF Research Database (Denmark)

    Madsen, Ulla; Breum, N. O.; Nielsen, Peter V.

    Capture efficiency of a local exhaust system, e.g. a kitchen hood, should include only contaminants being direct captured. In this study basic concepts of local exhaust capture efficiency are given, based on the idea of a control box. A validated numerical model is used for estimation of the capt......Capture efficiency of a local exhaust system, e.g. a kitchen hood, should include only contaminants being direct captured. In this study basic concepts of local exhaust capture efficiency are given, based on the idea of a control box. A validated numerical model is used for estimation...

  12. Exhaustion from prolonged gambling

    Institute of Scientific and Technical Information of China (English)

    Fatimah Lateef

    2013-01-01

    Complaints of fatigue and physical exhaustion are frequently seen in the acute medical setting, especially amongst athletes, army recruits and persons involved in strenuous and exertional physical activities.Stress-induced exhaustion, on the other hand, is less often seen, but can present with very similar symptoms to physical exhaustion.Recently, three patients were seen at theDepartment ofEmergencyMedicine, presenting with exhaustion from prolonged involvement in gambling activities.The cases serve to highlight some of the physical consequences of prolonged gambling.

  13. 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.

  14. 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.

  15. Condensation Dripping Water Detection and Its Control Method from Exhaust Pipe of Gasohol Vehicle under Low Environmental Temperature Conditions: A Case Study in Harbin, China

    OpenAIRE

    Guangdong Tian; Tiangang Qiang; Jiangwei Chu; Guangming Qiao

    2012-01-01

    Gasohol is one of renewable clean alternative energies, which is widely used around the world. Gasohol had been raised to be used in 9 provinces of China since 2001. However, its closed use was merely promoted in Heilongjiang province since November 1, 2004. Moreover, this issue aroused extensive discussions and controversies. One of them is the condensation dripping water issue from exhaust pipe in cold winter. Does the ethanol cause the road freezing in cold winter? To deal with this issue,...

  16. Control Technology of Exhaust Gas Emission from Marine Diesel Engine%船用柴油机有害物排放控制技术

    Institute of Scientific and Technical Information of China (English)

    庞海龙; 邓成林; 姚广涛; 资新运; 卜建国; 陈超

    2011-01-01

    This paper introduced the actual situation of atmospheric pollution caused by exhaust emission from marine diesel engines and expounded the regulations made by IMO for controlling exhaust emissions. And then, it summarized current methods to reduce SOx, NOx and PM in the exhaust gases. Finally, it pointed that the combination application of various technologies is the main development tendency of the emission reduction for marine diesel engine in the future.%介绍船舶柴油机排气对大气污染的现状及国际海事组织对船舶柴油机排放的控制法规;归纳总结了目前降低船舶柴油机氮氧化物、硫氧化物和颗粒物排放的主要技术措施,提出了多种技术综合运用是今后船舶柴油机减排发展必然趋势.

  17. High Temperature Gas-cooled Reactor Projected Markets and Scoping Economics

    Energy Technology Data Exchange (ETDEWEB)

    Larry Demick

    2010-08-01

    The NGNP Project has the objective of developing the high temperature gas-cooled reactor (HTGR) technology to supply high temperature process heat to industrial processes as a substitute for burning of fossil fuels, such as natural gas. Applications of the HTGR technology that have been evaluated by the NGNP Project for supply of process heat include supply of electricity, steam and high-temperature gas to a wide range of industrial processes, and production of hydrogen and oxygen for use in petrochemical, refining, coal to liquid fuels, chemical, and fertilizer plants.

  18. Performance Analysis of a Reciprocating Piston Expander and a Plate Type Exhaust Gas Recirculation Boiler in a Water-Based Rankine Cycle for Heat Recovery from a Heavy Duty Diesel Engine

    Directory of Open Access Journals (Sweden)

    Gunnar Latz

    2016-06-01

    Full Text Available The exhaust gas in an internal combustion engine provides favorable conditions for a waste-heat recovery (WHR system. The highest potential is achieved by the Rankine cycle as a heat recovery technology. There are only few experimental studies that investigate full-scale systems using water-based working fluids and their effects on the performance and operation of a Rankine cycle heat recovery system. This paper discusses experimental results and practical challenges with a WHR system when utilizing heat from the exhaust gas recirculation system of a truck engine. The results showed that the boiler’s pinch point necessitated trade-offs between maintaining adequate boiling pressure while achieving acceptable cooling of the EGR and superheating of the water. The expander used in the system had a geometric compression ratio of 21 together with a steam outlet timing that caused high re-compression. Inlet pressures of up to 30 bar were therefore required for a stable expander power output. Such high pressures increased the pump power, and reduced the EGR cooling in the boiler because of pinch-point effects. Simulations indicated that reducing the expander’s compression ratio from 21 to 13 would allow 30% lower steam supply pressures without adversely affecting the expander’s power output.

  19. Exhaust Structure Influence on Gas Flow Distribution in PSC-1O0 Guide Vane Cyclone Tube%排气结构对PSC-100型导叶式旋风管内流场分布的影响

    Institute of Scientific and Technical Information of China (English)

    王建军; 许文文; 金有海

    2011-01-01

    采用五孔球探针测量了不同排气结构参数(导流锥下口直径d1、开缝面积比a和开缝位置)的改变对PSC-100型导叶式旋风管内总压降和流场的影响.试验结果表明:带有导流锥的排气结构对分离有利;导流锥下口直径增大,气流旋转强度减小,颗粒分离所需离心力场减弱;导流锥开缝面积越大,分离空间内气旋强度越低;导流锥上侧缝开缝部位对旋风管内流场分布亦有影响.%By means of the intelligent five-hole pitot tube, the exhaust structure influence from the lower port d1 , the slotted area ratio a and the slotted position on the flow field distribution were investigated. Experimental results show that, an exhaust structure with diversion cone benefits centrifugal separation; with the enlargement of lower port d1 , the gas rotation intensity slows down and the centrifugal force to particle separation decreases; the gas rotation intensity slows down with the reduce of slotted area. The slotted position also influences flow field distribution.

  20. Impact of compression on gas transport in non-woven gas diffusion layers of high temperature polymer electrolyte fuel cells

    Science.gov (United States)

    Froning, Dieter; Yu, Junliang; Gaiselmann, Gerd; Reimer, Uwe; Manke, Ingo; Schmidt, Volker; Lehnert, Werner

    2016-06-01

    Gas transport in non-woven gas diffusion layers of a high-temperature polymer electrolyte fuel cell was calculated with the Lattice Boltzmann method. The underlying micro structure was taken from two sources. A real micro structure was analyzed in the synchrotron under the impact of a compression mask mimicking the channel/rib structure of a flow field. Furthermore a stochastic geometry model based on synchrotron X-ray tomography studies was applied. The effect of compression is included in the stochastic model. Gas transport in these micro structures was simulated and the impact of compression was analyzed. Fiber bundles overlaying the micro structure were identified which affect the homogeneity of the gas flow. There are significant deviations between the impact of compression on effective material properties for this type of gas diffusion layers and the Kozeny-Carman equation.

  1. Capture efficiency measurement of pollutants over a workbench with the reinforced slot exhaust system

    Directory of Open Access Journals (Sweden)

    Pavelek M.

    2013-04-01

    Full Text Available The paper deals with the measurement of the capture efficiency of pollutants by the slot reinforced exhaust system situated in two positions over the workbench. The slot reinforced exhaust system, which is known as REEXS, is the traditional slot exhaust hood equipped with an air supply inlet that intensifies exhausting along the axis of the exhaust hood. It can operate in traditional or reinforced exhaust modes. Measurements were made for the same air velocity in the suction slot and with the different momentum flux ratio of supplied and exhausted air flow. The tracer gas method was used for the capture efficiency measurement of the system. As the tracer gas the carbon dioxide was chosen. The knowledge of the shape and range of the effective exhaust area for various configurations in front of the exhaust hood is important for the exhaust hood setting according to a source of pollutants.

  2. SiC based MOSFET transistors for high temperature industrial gas sensing applications

    Science.gov (United States)

    Lloyd Spetz, Anita

    2000-03-01

    Field effect sensors based on silicon carbide have been demonstrated for industrial applications at high temperatures and in rough environments. Metal insulator silicon carbide, MISiC, Schottky diode devices as well as FET transistor devices that can be operated up to 700°C are presented. For high operation temperatures the sensors respond within milliseconds to a change between an oxidizing and reducing atmosphere, and cylinder specific monitoring of a combustion engine has been demonstrated. Changing the temperature and the type of gate metal gives sensors with diverse response patterns to different components in e.g. exhaust gases and flue gases. Sensor devices operating around 300°C with some selectivity to nitric oxide in synthetic diesel exhaust gases are presented. At a higher temperature, about 500°C, some selectivity to HC is found in synthetic petrol exhausts. Boilers of the size 0.5 - 5 MW constitute a potential market for combustion monitoring sensors. We have demonstrated MISiC devices with high selectivity to carbon monoxide in flue gases. References: Fast responding air/fuel sensor for individual cylinder control, A. Baranzahi, P. Tobias, A. Lloyd Spetz, I Lundström, P. Mårtensson, M. Glavmo, A. Göras, J. Nytomt, P. Salomonsson, and H. Larsson, SAE Technical Paper Series 972940, Combustion and Emisson Formation in SI Engines, (SP-1300) (1997) 231-240. MISiC Schottky Diodes as NOx sensors in simulated exhausts, H. Svenningstorp, P. Tobias, C. Wijk, I. Lundström, P. Salomonsson, L.-G. Ekedahl, and A. Lloyd Spetz, proc. Eurosensors XIII, The Hague, The Netherlands, September 12-15, pp. 501-504, 1999. Measurements with MISiC and MOS sensors in flue gases, L. Unéus, P. Ljung, M. Mattsson, P. Mårtenssson, R. Wigren, P. Tobias, I. Lundström, L-G. Ekedahl and A. Lloyd Spetz, proc. Eurosensors XIII, The Hague, The Netherlands, September 12-15, pp. 521-524, 1999.

  3. Numerical study of particle deposition and scaling in dust exhaust of cyclone separator

    Science.gov (United States)

    Xu, W. W.; Li, Q.; Zhao, Y. L.; Wang, J. J.; Jin, Y. H.

    2016-05-01

    The solid particles accumulation in the dust exhaust cone area of the cyclone separator can cause the wall wear. This undoubtedly prevents the flue gas turbine from long period and safe operation. So it is important to study the mechanism how the particles deposited and scale on dust exhaust cone area of the cyclone separator. Numerical simulations of gas-solid flow field have been carried out in a single tube in the third cyclone separator. The three-dimensionally coupled computational fluid dynamic (CFD) technology and the modified Discrete Phase Model (DPM) are adopted to model the gas-solid two-phase flow. The results show that with the increase of the operating temperature and processing capacity, the particle sticking possibility near the cone area will rise. The sticking rates will decrease when the particle diameter becomes bigger.

  4. Gas diffusion and temperature dependence of bubble nucleation during irradiation

    DEFF Research Database (Denmark)

    Foreman, A. J. E.; Singh, Bachu Narain

    1986-01-01

    The continuous production of gases at relatively high rates under fusion irradiation conditions may enhance the nucleation of cavities. This can cause dimensional changes and could induce embrittlement arising from gas accumulation on grain boundaries. Computer calculations have been made of the...... activation energy below Tm/2. The coalescence of diatomic nuclei due to Brownian motion markedly improves the agreement and also provides a well-defined terminal density. Bubble nucleation by this mechanism is sufficiently fast to inhibit any appreciable initial loss of gas to grain boundaries during the...... nucleation period, provided that incubation effects do not occur....

  5. 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.

  6. High Temperature Gas-Cooled Test Reactor Options Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Sterbentz, James William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bayless, Paul David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    Preliminary scoping calculations are being performed for a 100 MWt gas-cooled test reactor. The initial design uses standard prismatic blocks and 15.5% enriched UCO fuel. Reactor physics and thermal-hydraulics simulations have been performed to identify some reactor design features to investigate further. Current status of the effort is described.

  7. Immune Exhaustion and Transplantation.

    Science.gov (United States)

    Sanchez-Fueyo, A; Markmann, J F

    2016-07-01

    Exhaustion of lymphocyte function through chronic exposure to a high load of foreign antigen is well established for chronic viral infection and antitumor immunity and has been found to be associated with a distinct molecular program and characteristic cell surface phenotype. Although exhaustion has most commonly been studied in the context of CD8 viral responses, recent studies indicate that chronic antigen exposure may affect B cells, NK cells and CD4 T cells in a parallel manner. Limited information is available regarding the extent of lymphocyte exhaustion development in the transplant setting and its impact on anti-graft alloreactivity. By analogy to the persistence of a foreign virus, the large mass of alloantigen presented by an allograft in chronic residence could provide an ideal setting for exhausting donor-reactive T cells. The extent of T cell exhaustion occurring with various allografts, the kinetics of its development, whether exhaustion is influenced positively or negatively by different immunosuppressants, and the impact of exhaustion on graft survival and tolerance development remains a fertile area for investigation. Harnessing or encouraging the natural processes of exhaustion may provide a novel means to promote graft survival and transplantation tolerance. PMID:26729653

  8. Duplex tab exhaust nozzle

    Science.gov (United States)

    Gutmark, Ephraim Jeff (Inventor); Martens, Steven (nmn) (Inventor)

    2012-01-01

    An exhaust nozzle includes a conical duct terminating in an annular outlet. A row of vortex generating duplex tabs are mounted in the outlet. The tabs have compound radial and circumferential aft inclination inside the outlet for generating streamwise vortices for attenuating exhaust noise while reducing performance loss.

  9. Noble-gas hydrides: new chemistry at low temperatures.

    Science.gov (United States)

    Khriachtchev, Leonid; Räsänen, Markku; Gerber, R Benny

    2009-01-20

    Noble-gas chemistry has been undergoing a renaissance in recent years, due in large part to noble-gas hydrides, HNgY, where Ng = noble-gas atom and Y = electronegative fragment. These molecules are exceptional because of their relatively weak bonding and large dipole moments, which lead to strongly enhanced effects of the environment, complexation, and reactions. In this Account, we discuss the matrix-isolation synthesis of noble-gas hydrides, their spectroscopic and structural properties, and their stabilities.This family of species was discovered in 1995 and now has 23 members that are prepared in noble-gas matrices (HXeBr, HKrCl, HXeH, HXeOH, HXeO, etc.). The preparations of the first neutral argon molecule, HArF, and halogen-free organic noble-gas molecules (HXeCCH, HXeCC, HKrCCH, etc.) are important highlights of the field. These molecules are formed by the neutral H + Ng + Y channel. The first addition reaction involving HNgY molecules was HXeCC + Xe + H --> HXeCCXeH, and this led to the first hydride with two noble-gas atoms (recently extended by HXeOXeH). The experimental synthesis of HNgY molecules starts with production of H and Y fragments in solid noble gas via the UV photolysis of suitable precursors. The HNgY molecules mainly form upon thermal mobilization of the fragments.One of the unusual properties of these molecules is the hindered rotation of some HNgY molecules in solid matrices; this has been theoretically modeled. HNgY molecules also have unusual solvation effects, and the H-Xe stretching mode shifts to higher frequencies (up to about 150 cm-1) upon interaction with other species.The noble hydrides have a new bonding motif: HNgY molecules can be represented in the form (H-Ng)+Y-, where (H-Ng)+ is mainly covalent, whereas the interaction between (HNg)+ and Y- is predominantly ionic. The HNgY molecules are highly metastable species representing high-energy materials. The decomposition process HNgY --> Ng + HY is always strongly exoergic

  10. Microwave and Conventional Pyrolysis of Coffee Hulls at Different Temperatures for a Hydrogen Rich Gas

    OpenAIRE

    Menendez, Angel; Fernandez, Yolanda; Dominguez, Antonio; Pis, Juan; Valente Nabais, Joao; Carrott, Peter; Carrott, Manuela

    2006-01-01

    Microwave and Conventional Pyrolysis of Coffee Hulls at Different Temperatures for a Hydrogen Rich Gas. The paper reports the comparison of using a microwave and a conventional furnace to do the pysolysis of the coffee hulls.

  11. Characteristic features of the operation of high-temperature heat pipes with a noncondesable gas

    Science.gov (United States)

    Tolubinskiy, V. I.; Shevchuk, Ye. N.

    1987-01-01

    The principal concepts related to the nature of the processes occurring in high-temperature heat pipes with a noncondensable gas are examined, and guidelines for the development of such heat pipes are presented. The discussion is illustrated by experimental results obtained for a horizontal sodium heat pipe (diameter, 18/1 mm; length, 710 mm). In particular, attention is given to the starting dynamics and mechanisms, the shape of the vapor-gas front, and the vapor-gas front velocity.

  12. 基于AVR单片机的汽车尾气检测系统设计%Design of automobile exhaust gas detection system based on AVR

    Institute of Scientific and Technical Information of China (English)

    姚宁; 郭朝龙; 翁凌云; 葛承滨

    2014-01-01

    针对当前汽车尾气污染加重和检测标准日益完善的现状,为了弥补传统汽车尾气检测系统在测量精度、稳定性、人机操作等方面存在的不足,提出了一种基于AVR单片机的汽车尾气检测系统设计方案。系统以ATMEGA8L为核心控制器,主要由传感器模块、信号采集调理电路、A/D转换器以及显示模块等组成。实验结果表明,系统具有测量精度高、稳定可靠、人机交互性好等优点。%Nowadays the automotive exhaust pollution has been increasing and the detecting standard is increasingly sophis⁃ticated. A design scheme of an automobile exhaust detecting system based on AVR is proposed to overcome the shortage of tradi⁃tional automotive exhaust detection systems in measuring accuracy,stability and man⁃machine operation. ATMEGA8L is taken as the core controller of the system,which is composed of the sensor module,signal acquisition and conditioning circuit,A/D converter,and display module. The tested results show that the system has the advantages of high⁃accuracy,high stability,high reliability and good human⁃computer interaction.

  13. 30 CFR 7.101 - Surface temperature tests.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Surface temperature tests. 7.101 Section 7.101... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be... the rated horsepower specified in § 7.97(a)(2). (ii) Install sufficient temperature measuring...

  14. Energy and exergy analyses of a bottoming Rankine cycle for engine exhaust heat recovery

    International Nuclear Information System (INIS)

    In this paper, a theoretical study on the thermodynamic processes of a bottoming Rankine cycle for engine waste heat recovery is conducted from the viewpoints of energy balance and exergy balance. A theoretical formula and an exergy distribution map for qualitative analyses of the main operating parameters are presented under simplified conditions when exhaust gas is selected as the only heat source. Five typical working fluids, which are always selected by manufacturers for different types of engines, are compared under various operating conditions in Matlab software. The results show that working fluid properties, evaporating pressure and superheating temperature are the main factors influencing the system design and performances. The global recovery efficiency does not exceed 0.14 under typical operating conditions. Ethanol and R113 show better thermodynamic performances in the whole exhaust gas temperature range. In addition, the optimal evaporating pressure usually does not exist in engine exhaust heat recovery, and the distributions of exergy destruction are varied with working fluid categories and system design constraints. - Highlights: • A theoretical formula for qualitative analyses of the Rankine cycle is proposed. • System exergy destruction is investigated with an exergy distribution map. • Design constraints of the bottoming Rankine cycle for ICEs are summarized. • The optimal evaporating pressure does not occur under typical exhaust conditions. • The exergy destruction depends on working fluid categories and system constraints

  15. The impact of carbon dioxide and exhaust gas recirculation on the oxidative reactivity of soot from ethylene flames and diesel engines

    Science.gov (United States)

    Al-Qurashi, Khalid O.

    Restrictive emissions standards to reduce nitrogen oxides (NOx) and particulate matter (PM) emissions from diesel engines necessitate the development of advanced emission control technology. The engine manufacturers in the United States have implemented the exhaust gas recirculation (EGR) and diesel particulate filters (DPF) to meet the stringent emissions limits on NOx and PM, respectively. Although the EGR-DPF system is an effective means to control diesel engine emissions, there are some concerns associated with its implementation. The chief concern with this system is the DPF regenerability, which depends upon several factors, among which are the physicochemical properties of the soot. Despite the plethora of research that has been conducted on DPF regenerability, the impact of EGR on soot reactivity and DPF regenerability is yet to be examined. This work concerns the impact of EGR on the oxidative reactivity of diesel soot. It is part of ongoing research to bridge the gap in establishing a relationship between soot formation conditions, properties, and reactivity. This work is divided into three phases. In the first phase, carbon dioxide (CO2) was added to the intake charge of a single cylinder engine via cylinders of compressed CO2. This approach simulates the cold-particle-free EGR. The results showed that inclusion of CO2 changes the soot properties and yields synergistic effects on the oxidative reactivity of the resulting soot. The second phase of this research was motivated by the findings from the first phase. In this phase, post-flame ethylene soot was produced from a laboratory co-flow laminar diffusion flame to better understand the mechanism by which the CO2 affects soot reactivity. This phase was accomplished by successfully isolating the dilution, thermal, and chemical effects of the CO2. The results showed that all of these effects account for a measurable increase in soot reactivity. Nevertheless, the thermal effect was found to be the most

  16. Minimization of steam requirements and enhancement of water-gas shift reaction with warm gas temperature CO2 removal

    Science.gov (United States)

    Siriwardane, Ranjani V; Fisher, II, James C

    2013-12-31

    The disclosure utilizes a hydroxide sorbent for humidification and CO.sub.2 removal from a gaseous stream comprised of CO and CO.sub.2 prior to entry into a water-gas-shift reactor, in order to decrease CO.sub.2 concentration and increase H.sub.2O concentration and shift the water-gas shift reaction toward the forward reaction products CO.sub.2 and H.sub.2. The hydroxide sorbent may be utilized for absorbtion of CO.sub.2 exiting the water-gas shift reactor, producing an enriched H.sub.2 stream. The disclosure further provides for regeneration of the hydroxide sorbent at temperature approximating water-gas shift conditions, and for utilizing H.sub.2O product liberated as a result of the CO.sub.2 absorption.

  17. Optical methods to study the gas exchange processes in large diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Gros, S.; Hattar, C. [Wartsila Diesel International Oy, Vaasa (Finland); Hernberg, R.; Vattulainen, J. [Tampere Univ. of Technology, Tampere (Finland). Plasma Technology Lab.

    1996-12-01

    To be able to study the gas exchange processes in realistic conditions for a single cylinder of a large production-line-type diesel engine, a fast optical absorption spectroscopic method was developed. With this method line-of-sight UV-absorption of SO{sub 2} contained in the exhaust gas was measured as a function of time in the exhaust port area in a continuously fired medium speed diesel engine type Waertsilae 6L20. SO{sub 2} formed during the combustion from the fuel contained sulphur was used as a tracer to study the gas exchange as a function of time in the exhaust channel. In this case of a 4-stroke diesel engine by assuming a known concentration of SO{sub 2} in the exhaust gas after exhaust valve opening and before inlet and exhaust valve overlap period, the measured optical absorption was used to determine the gas density and further the instantaneous exhaust gas temperature during the exhaust cycle. (author)

  18. Large-scale time-resolved digital particle image velocimetry (TR-DPIV) for measurement of high subsonic hot coaxial jet exhaust of a gas turbine engine

    International Nuclear Information System (INIS)

    The development of a highly configurable triple digital particle image velocimetry (DPIV) system is described, which is capable of acquiring both continuous, statistically independent measurements at up to 14 Hz and time-resolved PIV data at MHz rates. The system was used at QinetiQ's Noise Test Facility (NTF) as part of the EU-funded CoJeN programme to obtain measurements from high subsonic (Mach ≤ 0.9), hot (∼500 °C), large (1/10th) scale coaxial jet flows at a standoff distance of ∼1 m. High-resolution time-averaged velocity and turbulence data were obtained for complete coaxial engine exhaust plumes down to 4 m (20 jet diameters) from the nozzle exit in less than 1 h. In addition, the system allowed volumetric data to be obtained, enabling fast assessment of spatial alignment of nozzle configurations. Furthermore, novel six-frame time-series data-capture is demonstrated up to 330 kHz, used to calculate time–space correlations within the exhaust, allowing for study of spatio-temporal developments in the jet, associated with jet-noise production. The highly automated system provides synchronization triggers for simultaneous acquisition from different measurement systems (e.g. LDA) and is shown to be versatile, rugged, reliable and portable, operating remotely in a hostile environment. Data are presented for three operating conditions and two nozzle geometries, providing a database to be used to validate CFD models of coaxial jet flow

  19. Simulation of Multi-Steady States in Low Temperature Gas Discharge

    Institute of Scientific and Technical Information of China (English)

    李弘; 胡希伟

    2004-01-01

    This article presents hydrodynamics simulation of multi-steady states and mode transition by DC-beam-injected gas discharge, and provides a model approach to hysteresis and distinct forms of multi-steady states. The critical transition conditions of the three discharge modes (temperature limited mode, Langmuir mode, and space charge limited mode) are estimated to be dependent on the gas pressure and the filament temperature. Various forms of the multi-steady states in gas discharge can be uniformly explained by the displacement of the mutant positions. The simulation results are in a good agreement with those of the experiments.

  20. Gas-Liquid Mass Transfer in a Slurry Bubble Column Reactor under High Temperature and

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The gas-liquid mass transfer of H2 and CO in a high temperature and high-pressure three-phase slurry bubble column reactor is studied. The gas-liquid volumetric mass transfer coefficients κLα are obtained by measuring the dissolution rate of H2 and CO. The influences of the main operation conditions, such as temperature, pressure, superficial gas velocity and solid concentration, are studied systematically. Two empirical correlations are proposed to predict κLα values for H2 and CO in liquid paraffin/solid particles slurry bubble column reactors.

  1. Conditions for lowering the flue gas temperature; Foerutsaettning foer saenkning av roekgastemperatur

    Energy Technology Data Exchange (ETDEWEB)

    Nordling, Magnus

    2012-02-15

    In heat and power production, the efficiency of the power plant increases the larger share of heat from the flue gas that is converted to power. However, this also implies that the temperature of the heat exchanging surfaces is lowered. If the temperature is lowered to a temperature below the dew point of the flue gas, this would result in condensation of the gas, which in turn elevates the risk of serious corrosion attack on the surfaces where condensation occurs. Thus, it is important to determine the dew point temperature. One way of determining the dew point temperature is to use data on composition of the fuel together with operation parameters of the plant, thus calculating the dew point temperature. However, this calculation of the dew point is not so reliable, especially if hygroscopic salts are present. Therefore, for safety reasons, the temperature of the flue gas is kept well above the dew point temperature. This results in lowered over-all efficiency of the plant. It could also be expected that for a certain plant, some construction materials under certain operation conditions would have corrosion characteristics that may allow condensation on the surface without severe and unpredictable corrosion attack. However, by only using operation parameters and fuel composition, it is even harder to predict the composition of the condensate at different operation temperatures than to calculate the dew point temperature. If the dew point temperature was known with a greater certainty, the temperature of the flue gas could be kept lower, just above the estimated value of the dew point, without any increased risk for condensation. If, in addition, also the resulting composition of the condensate at different temperatures below the dew point is known, it can be predicted if the construction materials of the flue gas channel were compatible with the formed condensate. If they are compatible, the flue gas temperature can be further lowered from the dew point

  2. An Explosive Range Model Based on the Gas Composition, Temperature, and Pressure during Air Drilling

    Directory of Open Access Journals (Sweden)

    Xiangyu Fan

    2016-01-01

    Full Text Available Air drilling is low cost and effectively improves the penetration rate and causes minimal damage to liquid-sensitive pay zones. However, there is a potential downhole explosion when combustible gas mixed with drilling fluid reaches the combustible condition. In this paper, based on the underground combustion mechanism, an explosive range calculation model is established. This model couples the state equation and the empirical formula method, which considers the inert gas content, pressure, mixed gas component, and temperature. The result shows that increase of the inert gas content narrows the explosive range, while increase of the gas temperature and pressure improves the explosive range. A case in Chongqing, China, is used to validate the explosive range calculation model.

  3. High temperature, high pressure gas loop - the Component Flow Test Loop (CFTL)

    International Nuclear Information System (INIS)

    The high-pressure, high-temperature, gas-circulating Component Flow Test Loop located at Oak Ridge National Laboratory was designed and constructed utilizing Section III of the ASME Boiler and Pressure Vessel Code. The quality assurance program for operating and testing is also based on applicable ASME standards. Power to a total of 5 MW is available to the test section, and an air-cooled heat exchanger rated at 4.4 MW serves as heat sink. The three gas-bearing, completely enclosed gas circulators provide a maximum flow of 0.47 m3/s at pressures to 10.7 MPa. The control system allows for fast transients in pressure, power, temperature, and flow; it also supports prolonged unattended steady-state operation. The data acquisition system can access and process 10,000 data points per second. High-temperature gas-cooled reactor components are being tested

  4. High temperature, high pressure gas loop - the Component Flow Test Loop (CFTL)

    Energy Technology Data Exchange (ETDEWEB)

    Gat, U.; Sanders, J.P.; Young, H.C.

    1984-01-01

    The high-pressure, high-temperature, gas-circulating Component Flow Test Loop located at Oak Ridge National Laboratory was designed and constructed utilizing Section III of the ASME Boiler and Pressure Vessel Code. The quality assurance program for operating and testing is also based on applicable ASME standards. Power to a total of 5 MW is available to the test section, and an air-cooled heat exchanger rated at 4.4 MW serves as heat sink. The three gas-bearing, completely enclosed gas circulators provide a maximum flow of 0.47 m/sup 3//s at pressures to 10.7 MPa. The control system allows for fast transients in pressure, power, temperature, and flow; it also supports prolonged unattended steady-state operation. The data acquisition system can access and process 10,000 data points per second. High-temperature gas-cooled reactor components are being tested.

  5. Effects of Outside Air Temperature on Movement of Phosphine Gas in Concrete Elevator Bins

    Science.gov (United States)

    Studies that measured the movement and concentration of phosphine gas in upright concrete bins over time indicated that fumigant movement was dictated by air currents, which in turn, were a function of the difference between the average grain temperature and the average outside air temperature durin...

  6. Research and development for high temperature gas cooled reactor in Japan

    International Nuclear Information System (INIS)

    The paper describes the current status of High Temperature Gas Cooled Reactor research and development work in Japan, with emphasis on the Experimental Very High Temperature Reactor (Exp. VHTR) to be built by Japan Atomic Energy Research Institute (JAERI) before the end of 1985. The necessity of construction of Exp. VHTR was explained from the points of Japanese energy problems and resources

  7. Non-Conventional Plasma Assisted Catalysts for Diesel Exhaust Treatment: A Case Study

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper reports the application of pulse discharges along with catalysts in treating the exhaust gas at higher temperatures. In the present work a plasma reactor, filled with catalysts, called as plasma catalytic reactor, is studied for removal of oxides of nitrogen, total hydrocarbons and carbon monoxide. The experiments are conducted on an actual diesel engine exhaust at no-load and at different temperatures starting from room temperature to 300℃. The removal efficiencies of these pollutants are studied. The experiments are carried out with both conventional and non-conventional catalysts. The idea is to explore the pollutant removal efficiency characteristics by non-conventional catalysts. The efficiency results are compared with that of conventional catalysts. The experiments are carried out at a constant pulse repetition rate of 120 pps. Both pellet and honeycomb type catalysts are used in the study.

  8. Neutral gas temperature estimates and metastable resonance energy transfer for argon-nitrogen discharges

    International Nuclear Information System (INIS)

    Rovibrational spectroscopy band fitting of the nitrogen (N2) second positive system is a technique used to estimate the neutral gas temperature of N2 discharges, or atomic discharges with trace amounts of a N2 added. For mixtures involving argon and N2, resonant energy transfer between argon metastable atoms (Ar*) and N2 molecules may affect gas temperature estimates made using the second positive system. The effect of Ar* resonance energy transfer is investigated here by analyzing neutral gas temperatures of argon-N2 mixtures, for N2 percentages from 1% to 100%. Neutral gas temperature estimates are higher than expected for mixtures involving greater than 5% N2 addition, but are reasonable for argon with less than 5% N2 addition when compared with an analytic model for ion-neutral charge exchange collisional heating. Additional spatiotemporal investigations into neutral gas temperature estimates with 10% N2 addition demonstrate that although absolute temperature values may be affected by Ar* resonant energy transfer, spatiotemporal trends may still be used to accurately diagnose the discharge

  9. Neutral gas temperature estimates and metastable resonance energy transfer for argon-nitrogen discharges

    Energy Technology Data Exchange (ETDEWEB)

    Greig, A., E-mail: amelia.greig@anu.edu.au; Charles, C.; Boswell, R. W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601 (Australia)

    2016-01-15

    Rovibrational spectroscopy band fitting of the nitrogen (N{sub 2}) second positive system is a technique used to estimate the neutral gas temperature of N{sub 2} discharges, or atomic discharges with trace amounts of a N{sub 2} added. For mixtures involving argon and N{sub 2}, resonant energy transfer between argon metastable atoms (Ar*) and N{sub 2} molecules may affect gas temperature estimates made using the second positive system. The effect of Ar* resonance energy transfer is investigated here by analyzing neutral gas temperatures of argon-N{sub 2} mixtures, for N{sub 2} percentages from 1% to 100%. Neutral gas temperature estimates are higher than expected for mixtures involving greater than 5% N{sub 2} addition, but are reasonable for argon with less than 5% N{sub 2} addition when compared with an analytic model for ion-neutral charge exchange collisional heating. Additional spatiotemporal investigations into neutral gas temperature estimates with 10% N{sub 2} addition demonstrate that although absolute temperature values may be affected by Ar* resonant energy transfer, spatiotemporal trends may still be used to accurately diagnose the discharge.

  10. Morphology-inspired low-temperature liquefied petroleum gas sensors of indium oxide

    International Nuclear Information System (INIS)

    Low-temperature wet chemical method has been applied to produce indium oxide (In2O3) nanostructures viz. cracked-cubes and the maize-corns which were then employed for their structure, morphology and surface-related measurements and finally envisaged in detection of liquefied petroleum gas (LPG) at different temperatures and concentrations. At 1000 ppm LPG, cracked-cube-based In2O3 sensor demonstrated lower operating temperature (135 °C) and gas sensitivity (44.35%) than the maize-corn-type (155 °C, 36.51%). Except moderate difference in sensitivity there was negligible difference in response and recovery periods

  11. Gas Temperature and Radiative Heat Transfer in Oxy-fuel Flames

    DEFF Research Database (Denmark)

    Bäckström, Daniel; Johansson, Robert; Andersson, Klas;

    This work presents measurements of the gas temperature, including fluctuations, and its influence on the radiative heat transfer in oxy-fuel flames. The measurements were carried out in the Chalmers 100 kW oxy-fuel test unit. The in-furnace gas temperature was measured by a suction pyrometer...... on the radiative heat transfer shows no effect of turbulence-radiation interaction. However, by comparing with temperature fluctuations in other flames it can be seen that the fluctuations measured here are relatively small. Further research is needed to clarify to which extent the applied methods can account...

  12. Critical temperature of Bose-Einstein condensation for weakly interacting bose gas in a potential trap

    Institute of Scientific and Technical Information of China (English)

    YU; Xuecai; YE; Yutang; WU; Yunfeng; XIE; Kang; CHENG; Lin

    2005-01-01

    The critical temperature of Bose-Einstein condensation at minimum momentum state for weakly interacting Bose gases in a power-law potential and the deviation of the critical temperature from ideal bose gas are studied. The effect of interaction on the critical temperature is ascribed to the ratiao α/λc, where α is the scattering length for s wave and λc is de Broglie wavelength at critical temperature. As α/λc<<1/(2π)2, the interaction is negligible. The presented deviation of the critical temperature for three dimensional harmonic potential is well in agreement with recent measurement of critical temperature for 87Rb bose gas trapped in a harmonic well.

  13. A Parameter Study of the Dust and Gas Temperature in a Field of Young Stars

    CERN Document Server

    Urban, Andrea; Doty, Steven D

    2007-01-01

    We model the thermal effect of young stars on their surrounding environment in order to understand clustered star formation. We take radiative heating of dust, dust-gas collisional heating, cosmic-ray heating, and molecular cooling into account. Using Dusty, a spherical continuum radiative transfer code, we model the dust temperature distribution around young stellar objects with various luminosities and surrounding gas and dust density distributions. We have created a grid of dust temperature models, based on our modeling with Dusty, which we can use to calculate the dust temperature in a field of stars with various parameters. We then determine the gas temperature assuming energy balance. Our models can be used to make large-scale simulations of clustered star formation more realistic.

  14. Measurement of neutral gas temperature in a 13.56 MHz inductively coupled plasma

    Energy Technology Data Exchange (ETDEWEB)

    Jayapalan, Kanesh K.; Chin, Oi Hoong [Plasma Technology Research Centre, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-04-24

    Measuring the temperature of neutrals in inductively coupled plasmas (ICP) is important as heating of neutral particles will influence plasma characteristics such as the spatial distributions of plasma density and electron temperature. Neutral gas temperatures were deduced using a non-invasive technique that combines gas actinometry, optical emission spectroscopy and simulation which is described here. Argon gas temperature in a 13.56 MHz ICP were found to fall within the range of 500 − 800 K for input power of 140 − 200 W and pressure of 0.05 − 0.2 mbar. Comparing spectrometers with 0.2 nm and 0.5 nm resolution, improved fitting sensitivity was observed for the 0.2 nm resolution.

  15. Observation of electron-temperature fluctuations triggered by supersonic gas puffing in the LHD

    International Nuclear Information System (INIS)

    Non-local transport and electron temperature fluctuations triggered by supersonic gas puffing (SSGP) in high-temperature helical plasmas in the Large Helical Device (LHD) are reported. After a short-pulse SSGP, the core electron temperature increased while the edge electron temperature decreased. SSGP triggered a longer core temperature increase than that triggered by a small impurity pellet injection. The temperature profile, which was relatively flat inside the half minor radius before SSGP, became parabolic after non-local transport was triggered. Fluctuations were excited in the electron temperature signals around the half minor radius. The frequency of these fluctuations increased from ∼ 400 Hz to ∼ 1 kHz within ∼ 0.1 s and the amplitude decreased correspondingly. The temperature fluctuations inside and outside of the half minor radius had opposite phases. Magnetic fluctuations resonating near the half minor radius were observed simultaneously with the electron temperature fluctuations. (author)

  16. Temperature and vibrational distribution function in high-pressure diatomic gas mixture

    Science.gov (United States)

    Lou, Guofeng; Lempert, Walter R; Adamovich, Igor V; Rich, William J

    2009-03-01

    Temperatures and vibrational populations are investigated experimentally and numerically in a CO-N2-O2 gas mixture. By spatially resolved Raman Q-branch spectra measurement, the strong vibrational excitation was observed in the gas mixtures at a high gas pressure. Numerical calculation, which incorporates both major processes of molecular energy transfer and diffusion of vibrationally excited species across the spatially nonuniform excitation region, provides indepth perception of vibrational kinetics of these diatomic molecular gas mixtures and is verified by the experimental data. The results demonstrate that strong vibrational nonequilibrium for all diatomic species can be sustained by the optical pumping method with a focused CO laser in a relatively cold (300-400 K) molecular gas mixture up to one atmospheric pressure. However, the results also demand further investigations on determining accurate rates of the V-V exchange gas mixture such as for N2-O2.

  17. Thermal barrier coating on high temperature industrial gas turbine engines

    Science.gov (United States)

    Carlson, N.; Stoner, B. L.

    1977-01-01

    The thermal barrier coating used was a yttria stabilized zirconia material with a NiCrAlY undercoat, and the base engine used to establish improvements was the P&WA FT50A-4 industrial gas turbine engine. The design benefits of thermal barrier coatings include simplified cooling schemes and the use of conventional alloys in the engine hot section. Cooling flow reductions and improved heating rates achieved with thermal barrier coating result in improved performance. Economic benefits include reduced power production costs and reduced fuel consumption. Over the 30,000 hour life of the thermal barrier coated parts, fuel savings equivalent to $5 million are projected and specific power (megawatts/mass of engine airflow) improvements on the order of 13% are estimated.

  18. Effect of ionol extraction temperature onto its gas chromatographic detection at transformer oil

    OpenAIRE

    Sergiy V. Zaitsev

    2015-01-01

    The gas chromatography used for detecting antioxidizing additive ionol at transformer oil presence helps to ensure reliable operation of oil-filled electrical equipment. Changes in the ionol preliminary extraction temperature do affect the reliability of measurement result. This study aim consisted in investigating the temperature effect on the value of extraction degree and distribution coefficients for ionol in the system “oil — ionol — ethanol” at extraction temperatures 15...75 °C. The ex...

  19. Engineering task plan for five portable exhausters

    International Nuclear Information System (INIS)

    Exhausters will be employed to ventilate certain single-shell tanks (SSTs) during salt well pumping campaigns. Active ventilation is necessary to reduce the potential flammable gas inventory (LANL 1996a) in the dome space that may accumulate during steady-state conditions or during/after postulated episodic gas release events. The tanks described in this plan support the activities required to fabricate and test three 500 cfm portable exhausters in the 200 W area shops, and to procure, design, fabricate and test two 1000 cfm units. Appropriate Notice of Construction (NOC) radiological and toxic air pollutant permits will be obtained for the portable exhausters. The portable exhauster design media to be employed to support this task was previously developed for the 241-A-101 exhauster. The same design as A101 will be fabricated with only minor improvements to the design based upon operator input/lessons learned. The safety authorization basis for this program effort will follow SAD 36 (LANL 1996b), and each tank will be reviewed against this SAD for changes or updates. The 1000 cfm units will be designed by the selected offsite contractor according to the specification requirements in KHC-S-O490. The offsite units have been specified to utilize as many of the same components as the 500 cfm units to ensure a more cost effective operation and maintenance through the reduction of spare parts and additional procedures

  20. An inverse method for flue gas shielded metal surface temperature measurement based on infrared radiation

    Science.gov (United States)

    Zhang, B.; Xu, C. L.; Wang, S. M.

    2016-07-01

    The infrared temperature measurement technique has been applied in various fields, such as thermal efficiency analysis, environmental monitoring, industrial facility inspections, and remote temperature sensing. In the problem of infrared measurement of the metal surface temperature of superheater surfaces, the outer wall of the metal pipe is covered by radiative participating flue gas. This means that the traditional infrared measurement technique will lead to intolerable measurement errors due to the absorption and scattering of the flue gas. In this paper, an infrared measurement method for a metal surface in flue gas is investigated theoretically and experimentally. The spectral emissivity of the metal surface, and the spectral absorption and scattering coefficients of the radiative participating flue gas are retrieved simultaneously using an inverse method called quantum particle swarm optimization. Meanwhile, the detected radiation energy simulated using a forward simulation method (named the source multi-flux method) is set as the input of the retrieval. Then, the temperature of the metal surface detected by an infrared CCD camera is modified using the source multi-flux method in combination with these retrieved physical properties. Finally, an infrared measurement system for metal surface temperature is built to assess the proposed method. Experimental results show that the modified temperature is closer to the true value than that of the direct measured temperature.

  1. Effect of changes in seafloor temperature and sea-level on gas hydrate stability

    International Nuclear Information System (INIS)

    Natural gas hydrates occur in oceanic sediments and in permafrost regions around the world. As a greenhouse gas, large amounts of methane released from the global hydrate reservoir would have a significant impact on Earth's climate. The role of methane released by hydrate dissociation in climate change is uncertain. However, changes in global climate such as glaciation and warming can destabilize the hydrates. During the last glacial maximum, the sea level dropped about 100 meters. It has been suggested that the sea-level fall was associated with gas hydrate instability and seafloor slumping. This paper investigated the effect of changes in seafloor temperature and sea level on gas hydrate stability and on gas venting at the seafloor. A one-dimensional numerical computer model (simulator) was developed to describe methane hydrate formation, decomposition, reformation, and distribution with depth below the seafloor in the marine environment. The simulator was utilized to model hydrate distributions at two sites, notably Blake Ridge, located offshore South Carolina and Hydrate Ridge, located off the coast of Oregon. The numerical models for the two sites were conditioned by matching the sulfate, chlorinity, and hydrate distribution measurements. The effect of changes in seafloor temperature and sea-level on gas hydrate stability were then investigated. It was concluded that for Blake Ridge, changes in hydrate concentration were small. Both the changes in seafloor temperature and sea-level led to a substantial increase in gas venting at the seafloor for Hydrate Ridge. 17 refs., 8 figs

  2. Investigation and design optimization of exhaust-based thermoelectric generator system for internal combustion engine

    International Nuclear Information System (INIS)

    Highlights: • A 3-D model for exhaust-based thermoelectric waste heat recovery is developed. • Various heat, mass and electric transfer characteristics are elucidated. • Channel size needs to be moderate to balance heat transfer and pressure drop. • Bafflers need to be placed at all locations near all TEG modules. • Baffler angle needs to be sufficiently large, especially for downstream locations. - Abstract: Thermoelectric generator (TEG) has attracted considerable attention for the waste heat recovery of internal combustion engine. In this study, a 3-D numerical model for engine exhaust-based thermoelectric generator (ETEG) system is developed. By considering the detailed geometry of thermoelectric generator (TEG) and exhaust channel, the various transport phenomena are investigated, and design optimization suggestions are given. It is found that the exhaust channel size needs to be moderate to balance the heat transfer to TEG modules and pressure drop along channel. Increasing the number of exhaust channels may improve the performance, however, since more space and TEG modules are needed, the system size and cost need to be considered as well. Although only placing bafflers at the channel inlet could increase the heat transfer coefficient for the whole channel, the near wall temperature downstream might decrease significantly, leading to performance degradation of the TEG modules downstream. To ensure effective utilization of hot exhaust gas, the baffler angle needs to be sufficiently large, especially for the downstream locations. Since larger baffler angles increase the pressure drop significantly, it is suggested that variable baffler angles, with the angle increasing along the flow direction, might be a middle course for balancing the heat transfer and pressure drop. A single ETEG design may not be suitable to all the engine operating conditions, and making the number of exhaust channels and baffler angle adjustable according to different engine

  3. Mechanical Property and Its Comparison of Superalloys for High Temperature Gas Cooled Reactor

    International Nuclear Information System (INIS)

    Since structural materials for high temperature gas cooled reactor are used during long period in nuclear environment up to 1000 .deg. C, it is important to have good properties at elevated temperature such as mechanical properties (tensile, creep, fatigue, creep-fatigue), microstructural stability, interaction between metal and gas, friction and wear, hydrogen and tritium permeation, irradiation behavior, corrosion by impurity in He. Thus, in order to select excellent materials for the high temperature gas cooled reactor, it is necessary to understand the material properties and to gather the data for them. In this report, the items related to material properties which are needed for designing the high temperature gas cooled reactor were presented. Mechanical properties; tensile, creep, and fatigue etc. were investigated for Haynes 230, Hastelloy-X, In 617 and Alloy 800H, which can be used as the major structural components, such as intermediate heat exchanger (IHX), hot duct and piping and internals. Effect of He and irradiation on these structural materials was investigated. Also, mechanical properties; physical properties, tensile properties, creep and creep crack growth rate were compared for them, respectively. These results of this report can be used as important data to select superior materials for high temperature gas reactor

  4. Study on Deformation of Miniature Metal Bellows in Cryocooler Following Temperature Change of Internal Gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Ha [LIGNex1 Co. Ltd., Gumi (Korea, Republic of); Lee, Tae Won [Kumoh National Institute of Technology, Gumi (Korea, Republic of)

    2015-04-15

    A bellows is an important temperature control component in a Joule-Thomson micro-cryocooler. It is designed using a very thin shell, and the inside of the bellows is filled with nitrogen gas. The bellows is made of a nickel-cobalt alloy that maintains its strength and elastic properties in a wide range of temperatures from cryogenic to 300℃. The pressure of the gas and the volume within the bellows vary according to the temperature of the gas. As a result, the bellows contracts or expands in the axial direction like a spring. To explore this phenomenon, the deformation of the bellows and its internal volume must be calculated iteratively under a modified pressure until the state equation of the gas is satisfied at a given temperature. In this paper, the modified Benedict-Webb-Rubin state equation is adopted to describe the temperature-volume-pressure relations of the gas. Experiments were performed to validate the proposed method. The results of a numerical analysis and the experiments showed good agreement.

  5. 内部废气再循环柴油机燃烧过程分析及排放性能试验%Analysis of combustion process and emission performancetest for diesel engine using internal exhaust gas recirculation

    Institute of Scientific and Technical Information of China (English)

    贾和坤; 尹必峰; 何建光; 徐毅

    2015-01-01

    为了探索小型非道路柴油机采用内部废气再循环技术改善其排放性能的有效途径,该文提出了一种在进气凸轮上增加预进气凸轮实现柴油机内部废气再循环(internal exhaust gas recirculation, IEGR)的方案。通过拍摄柴油机燃烧过程中的火焰图片、测试缸内压力、计算燃烧放热率、火焰温度场、碳烟浓度分布场以及有害污染物的排放测试,对比分析了实施内部废气再循环前后,小型非道路柴油机燃烧过程及排放性能的变化趋势。结果表明:1760 r/min、50%负荷工况下,引入IEGR后由燃烧放热引起的第二压力峰值由5.49下降到5.43 MP,燃烧放热始点推迟了0.5℃A,瞬时放热率峰值由85.7下降到82.4 J/deg;缸内燃烧火焰平均温度降低,高温强辐射区域面积占有率峰值由30下降到10‰以内,而表征碳烟浓度的KL因子平均值的峰值由原机的40.5上升到67.4,且高浓度区域的比例显著增加。1760 r/min转速,引入IEGR后各负荷工况下的NOx排放均有所降低,而碳烟排放则呈现增加的趋势;结合供油提前角的协同优化,可以实现部分负荷工况下有效燃油消耗率、NOx及碳烟排放的同时降低,具有以实现整机性能优化的潜力。该研究工作为内部废弃再循环技术在小型非道路柴油机上的应用提供了参考。%With the sustained development of economy and technology, small non-road diesel engines are extensively applied in industrial and agricultural production. The single-cylinder engines, in particular, plays a crucial role in modern agriculture, working as the main power source for small-to medium-sized tractors and mini-farming machinery etc. Due to current situation of fuel issue in China and structure limitation of single-cylinder diesel engine, a new method is presented to improve combustion and emission performance using internal exhaust gas recirculation (IEGR) in terms of

  6. Reducing drag of a commuter train, using engine exhaust momentum

    Science.gov (United States)

    Ha, Dong Keun

    The objective of this thesis was to perform numerical investigations of two different methods of injecting fluid momentum into the air flow above a commuter train to reduce its drag. Based on previous aerodynamic modifications of heavy duty trucks in improving fuel efficiency, two structural modifications were designed and applied to a Metrolink Services commuter train in the Los Angeles (LA) County area to reduce its drag and subsequently improve fuel efficiency. The first modification was an L-shaped channel, added to the exhaust cooling fan above the locomotive roof to divert and align the exhaust gases in the axial direction. The second modification was adding an airfoil shaped lid over the L-shape channel, to minimize the drag of the perturbed structure, and thus reduce the overall drag. The computational fluid dynamic (CFD) software CCM+ from CD-Adapco with the ?-? turbulence model was used for the simulations. A single train set which consists of three vehicles: one locomotive, one trailer car and one cab car were used. All the vehicles were modeled based on the standard Metrolink fleet train size. The wind speed was at 90 miles per hour (mph), which is the maximum speed for the Orange County Metrolink line. Air was used as the exhaust gas in the simulation. The temperature of the exhausting air emitting out of the cooling fan on the roof was 150 F and the average fan speed was 120 mph. Results showed that with the addition of the lid, momentum injection results in reduced flow separation and pressure recovery behind the locomotive, which reduces the overall drag by at least 30%.

  7. High-temperature turbine technology program. Turbine subsystem design report: Low-Btu gas

    Energy Technology Data Exchange (ETDEWEB)

    Horner, M.W.

    1980-12-01

    The objective of the US Department of Energy High-Temperature Turbine Technology (DOE-HTTT) program is to bring to technology readiness a high-temperature (2600/sup 0/F to 3000/sup 0/F firing temperature) turbine within a 6- to 10-year duration, Phase II has addressed the performance of component design and technology testing in critical areas to confirm the design concepts identified in the earlier Phase I program. Based on the testing and support studies completed under Phase II, this report describes the updated turbine subsystem design for a coal-derived gas fuel (low-Btu gas) operation at 2600/sup 0/F turbine firing temperature. A commercial IGCC plant configuration would contain four gas turbines. These gas turbines utilize an existing axial flow compressor from the GE product line MS6001 machine. A complete description of the Primary Reference Design-Overall Plant Design Description has been developed and has been documented. Trends in overall plant performance improvement at higher pressure ratio and higher firing temperature are shown. It should be noted that the effect of pressure ratio on efficiency is significally enhanced at higher firing temperatures. It is shown that any improvement in overall plant thermal efficiency reflects about the same level of gain in Cost of Electricity (COE). The IGCC concepts are shown to be competitive in both performance and cost at current and near-term gas turbine firing temperatures of 1985/sup 0/F to 2100/sup 0/F. The savings that can be accumulated over a thirty-year plant life for a water-cooled gas turbine in an IGCC plant as compared to a state-of-the-art coal-fired steam plant are estimated. A total of $500 million over the life of a 1000 MW plant is projected. Also, this IGCC power plant has significant environmental advantages over equivalent coal-fired steam power plants.

  8. Investigations on burning efficiency and exhaust emission of in-line type emulsified fuel system

    Directory of Open Access Journals (Sweden)

    Yen Kuei Tseng, Hsien Chang Cheng

    2011-07-01

    Full Text Available 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 burning tests, the fuel saving can be over 8~15%. Also, from the comparison of decline for the heat value and total energy output of varies emulsified fuel, one can find that the water as the dispersed phase in the combustion process will leading 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%, that means the reduction of the exhaust gas is truly effectively. 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.

  9. Analysis on Impulse Characteristics of PDRE with Exhaust Measurements

    Science.gov (United States)

    Hu, Hong-bo; Weng, Chun-sheng; Lv, Xiao-jing; Li, Ning

    2014-06-01

    The exhaust characteristics related to impulse was investigated in a pulse detonation rocket engine (PDRE) by tunable diode laser absorption sensing system. The instantaneous parameters of temperature, velocity and pressure were obtained for exhaust at engine exit. Analysis on impulse characteristics based on control volume of the PDRE was conducted for a single operation circle with experimental results. It was concluded that the impulse (3.26 N·s) achieved by exhaust measurements was in agreement with that (3.09 N·s) by a load cell. The impulse caused by exhaust momentum experienced an extremely sharp ascending, a steep rising and a slow increment in sequence. The exhausts during the sharp ascending and steep rising were under expansion with high mass weighted average temperature (>1266 K), so there was a possible promotion for exhausts utilizing.

  10. Development of a Binary Mixture Gas Composition Instrument for Use in a Confined High Temperature Environment

    Science.gov (United States)

    Cadell, Seth R.

    With recent advancements in material science, industrial operations are being conducted at higher and higher temperatures. This is apparent in the nuclear industry where a division of the field is working to develop the High Temperature Gas Reactor and the Very High Temperature Gas Reactor concurrently. Both of these facilities will have outlet gas temperatures that are at significantly higher temperatures than the typical water cooled reactor. These increased temperatures provide improved efficiency for the production of hydrogen, provide direct heating for oil refineries, or more efficient electricity generation. As high temperature operations are being developed, instruments capable of measuring the operating parameters must be developed concurrently. Within the gas reactor community there is a need to measure the impurities within the primary coolant. Current devices will not survive the temperature and radiation environments of a nuclear reactor. An instrument is needed to measure the impurities within the coolant while living inside the reactor, where this instrument would measure the amount of the impurity within the coolant. There are many industrial applications that need to measure the ratio of two components, whether it be the amount of particulate in air that is typical to pneumatic pumping, or the liquid to gas ratio in natural gas as it flows through a pipeline. All of the measurements in these applications can be met using a capacitance sensor. Current capacitance sensors are built to operate at ambient temperatures with only one company producing a product that will handle a temperature of up to 400 °C. This maximum operating temperature is much too low to measure the gas characteristics in the High Temperature Gas Reactor. If this measurement technique were to be improved to operate at the expected temperatures, the coolant within the primary loop could be monitored for water leaks in the steam generator, carbon dust buildup entrained in the flow

  11. Temperature dependence of the particle/gas partition coefficient: An application to predict indoor gas-phase concentrations of semi-volatile organic compounds.

    Science.gov (United States)

    Wei, Wenjuan; Mandin, Corinne; Blanchard, Olivier; Mercier, Fabien; Pelletier, Maud; Le Bot, Barbara; Glorennec, Philippe; Ramalho, Olivier

    2016-09-01

    The indoor gas-phase concentrations of semi-volatile organic compounds (SVOCs) can be predicted from their respective concentrations in airborne particles by applying the particle/gas partitioning equilibrium. The temperature used for partitioning is often set to 25°C. However, indoor temperatures frequently differ from this reference value. This assumption may result in errors in the predicted equilibrium gas-phase SVOC concentrations. To improve the prediction model, the temperature dependence of the particle/gas partition coefficient must be addressed. In this paper, a theoretical relationship between the particle/gas partition coefficient and temperature was developed based on the SVOC absorptive mechanism. The SVOC particle/gas partition coefficients predicted by employing the derived theoretical relationship agree well with the experimental data retrieved from the literature (R>0.93). The influence of temperature on the equilibrium gas-phase SVOC concentration was quantified by a dimensionless analysis of the derived relationship between the SVOC particle/gas partition coefficient and temperature. The predicted equilibrium gas-phase SVOC concentration decreased by between 31% and 53% when the temperature was lowered by 6°C, while it increased by up to 750% when the indoor temperature increased from 15°C to 30°C. PMID:27152992

  12. Neutron radiography of a static density gradient of 3He gas at cryogenic temperatures

    Science.gov (United States)

    Wichmann, G.; Antognini, A.; Eggenberger, A.; Kirch, K.; Piegsa, F. M.; Soler, U.; Stahn, J.; Taqqu, D.

    2016-04-01

    We demonstrate a stationary helium gas density gradient which is needed for a proposed novel low-energy μ+ beam line. In a closed system with constant pressure the corresponding density gradient is only a function of the temperature. In a neutron radiography experiment two gas cells with different geometries were filled with 3He gas at constant pressures of about 10 mbar. Temperatures in the range from 6 K to 40 K were applied and density distributions with a maximum to minimum density ratio of larger than 3 were realized. The distribution was investigated employing the strongly neutron absorbing isotope 3He. A simple one-dimensional approach derived from Fourier's law describes the obtained gas density with a deviation < 2 %.

  13. Exhaust purification with on-board ammonia production

    Science.gov (United States)

    Robel, Wade J.; Driscoll, James J.; Coleman, Gerald N.; Knox, Kevin J.

    2009-06-30

    A power source is provided for use with selective catalytic reduction systems for exhaust-gas purification. The power source includes a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The second air-intake passage is fluidly isolated from the first air-intake passage. A fuel-supply device may be configured to supply fuel into the first exhaust passage, and a catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

  14. Phenols and nitrophenols as tropospheric pollutants: emissions from automobile exhausts and phase transfer in the atmosphere

    International Nuclear Information System (INIS)

    Motor exhaust gas from an automobile motor, operated under stationary conditions with unleaded gasoline, was sampled with two different impinger bath methods. The samples were analyzed by gas chromatography/mass spectrometry (GC/MS) for phenol, cresols and nitrated phenols. Phenol and cresols were measured in the range of 80 - 220 nmol/L of exhaust gas from a noncatalyst engine, and nitrated phenols were found in the range of 9-36 nmol/L. A large reduction of total phenols down to 7% and less was observed when the engine was operated with a regulated three-way catalytic converter. The result of this study shows that exhaust gas sampling of phenols with alkaline aqueous impinger solutions leads to an underestimation of phenol emissions, since phenols are not stable under high-pH conditions. In order to better assess the environmental fate of nitrated phenols, laboratory experiments were conducted to measure the Henry's law constants of a series of nitrated phenols. For that purpose an apparatus for dynamic determination of the Henry's law constants was constructed and successfully used. Special emphasis was put on temperature dependence of the Henry's law constants. 15 refs., 2 figs., 2 tabs

  15. Impact of the injection dose of exhaust gases, on work parameters of combustion engine

    Science.gov (United States)

    Marek, W.; Śliwiński, K.

    2016-09-01

    This article is another one from the series in which were presented research results indicated the possible areas of application of the pneumatic injection using hot combustion gases proposed by Professor Jarnuszkiewicz. This publication present the results of the control system of exhaust gas recirculation. The main aim of this research was to determine the effect of exhaust gas recirculation to the operating parameters of the internal combustion engine on the basis of laboratory measurements. All measurements were performed at a constant engine speed. These conditions correspond to the operation of the motor operating an electrical generator. The study was conducted on the four-stroke two-cylinder engine with spark ignition. The study were specifically tested on the air injection system and therefore the selection of the rotational speed was not bound, as in conventional versions of operating parameters of the electrical machine. During the measurement there were applied criterion which used power control corresponding to the requirements of load power, at minimal values of engine speed. Recirculation value determined by the following recurrent position control valve of the injection doses inflator gas for pneumatic injection system. They were studied and recorded, the impact of dose of gases recirculation to the operating and ecological engine parameters such as power, torque, specific fuel consumption, efficiency, air fuel ratio, exhaust gas temperature and nitrogen oxides and hydrocarbons.

  16. Development and industrial application of catalyzer for low-temperature hydrogenation hydrolysis of Claus tail gas

    Directory of Open Access Journals (Sweden)

    Honggang Chang

    2015-10-01

    Full Text Available With the implementation of more strict national environmental protection laws, energy conservation, emission reduction and clean production will present higher requirements for sulfur recovery tail gas processing techniques and catalyzers. As for Claus tail gas, conventional hydrogenation catalyzers are gradually being replaced by low-temperature hydrogenation catalyzers. This paper concentrates on the development of technologies for low-temperature hydrogenation hydrolysis catalyzers, preparation of such catalyzers and their industrial application. In view of the specific features of SO2 hydrogenation and organic sulfur hydrolysis during low-temperature hydrogenation, a new technical process involving joint application of hydrogenation catalyzers and hydrolysis catalyzers was proposed. In addition, low-temperature hydrogenation catalyzers and low-temperature hydrolysis catalyzers suitable for low-temperature conditions were developed. Joint application of these two kinds of catalyzers may reduce the inlet temperatures in the conventional hydrogenation reactors from 280 °C to 220 °C, at the same time, hydrogenation conversion rates of SO2 can be enhanced to over 99%. To further accelerate the hydrolysis rate of organic sulfur, the catalyzers for hydrolysis of low-temperature organic sulfur were developed. In lab tests, the volume ratio of the total sulfur content in tail gas can be as low as 131 × 10−6 when these two kinds of catalyzers were used in a proportion of 5:5 in volumes. Industrial application of these catalyzers was implemented in 17 sulfur recovery tail gas processing facilities of 15 companies. As a result, Sinopec Jinling Petrochemical Company had outstanding application performances with a tail gas discharging rate lower than 77.9 mg/m3 and a total sulfur recovery of 99.97%.

  17. Gas temperature effect on the time for onset of particle nucleation in argon diluted acetylene plasma

    CERN Document Server

    Stefanovic, I; Berndt, J; Winter, J; Stefanovic, Ilija; Kovacevic, Eva; Berndt, Johannes; Winter, Jorg

    2004-01-01

    In our work we are focused on study of powder formation in C2H2/Ar plasmas. In this scope we used a combination of FTIR and mass spectroscopy, which are the mostly used experimental techniques for plasma powder formation diagnostics. To test the proposed mechanism for particle nucleation delay we measured the particle nucleation under different plasma conditions: firstly we increased the gas temperature and secondly we changed the background gas from argon to helium.

  18. Mechanical properties of structural materials for high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    Structural materials for high temperature gas cooled reactor should have good properties such as mechanical properties (tensile, creep, fatigue, creep-fatigue), microstructural stability, interaction between metal and gas, friction and wear, hydrogen and tritium permeation, irradiation behavior, corrosion by impurity in He. Mechanical properties of major structural materials, such as pressure vessel, heat exchanger, control rod, were investigated. Effect of He and irradiation on these structural materials were investigated

  19. CO-dark gas and molecular filaments in Milky Way-type galaxies - II: The temperature distribution of the gas

    CERN Document Server

    Glover, Simon C O

    2016-01-01

    We investigate the temperature distribution of CO-dark molecular hydrogen (H2) in a series of disk galaxies simulated using the AREPO moving-mesh code. In conditions similar to those in the Milky Way, we find that H2 has a flat temperature distribution ranging from 10 - 100 K. At $T 30$ K, the H2 fraction spans a broader range and the CO content is small, allowing us to classify gas in these two regimes as CO-bright and CO-dark, respectively. The mean sound speed in the CO-dark H2 is 0.64 km/s, significantly lower than the value in the cold atomic gas (1.15 km/s), implying that the CO-dark molecular phase is more susceptible to turbulent compression and gravitational collapse than its atomic counterpart. We further show that the temperature of the CO-dark H2 is highly sensitive to the strength of the interstellar radiation field, but that conditions in the CO-bright H2 remain largely unchanged. Finally, we examine the usefulness of the [CII] and [OI] fine structure lines as tracers of the CO-dark gas. We sho...

  20. Galaxy Clusters at the Edge: Temperature, Entropy, and Gas Dynamics at the Virial Radius

    CERN Document Server

    Burns, Jack O; O'Shea, Brian W

    2010-01-01

    Recently, Suzaku has produced temperature and entropy profiles, along with profiles of gas density, gas fraction, and mass, for multiple galaxy clusters out to ~r_200 (~= virial radius). In this paper, we compare these novel X-ray observations with results from N-body + hydrodynamic adaptive mesh refinement cosmological simulations using the Enzo code. There is excellent agreement in the temperature, density, and entropy profiles between a sample of 27 mostly substructure-free massive clusters in the simulated volume and the observed clusters. This supports our previous contention that clusters have "universal" outer temperature profiles. Furthermore, it appears that the simplest adiabatic gas physics used in these Enzo simulations is adequate to model the outer regions of these clusters without other mechanisms (e.g., non-gravitational heating, cooling, magnetic fields, or cosmic rays). However, the outskirts of these clusters are not in hydrostatic equilibrium. There is significant bulk flow and turbulence ...