WorldWideScience

Sample records for exhaust gas temperature

  1. Effect of Gas Turbine Exhaust Temperature, Stack Temperature and Ambient Temperature on Overall Efficiency of Combine Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    M.N.Khan

    2010-12-01

    Full Text Available The gas turbine exhaust temperature, stack temperature and ambient temperature play a very important role during the predication of the performance of combine cycle power plant. This paper covers parametric analysis of effects of gas turbine exhaust temperature, stack temperature and ambient temperature on the overall efficiency of combine cycle power plant keeping the gas turbine efficiency as well as steam turbine efficiency constant. The results shows that out of three variables i.e. turbine exhaust temperature, stack temperature and ambient temperature, the most dominating factor of increasing the overall efficiency of the combine cycle power plant is the stack temperature.

  2. Effect of Gas Turbine Exhaust Temperature, Stack Temperature and Ambient Temperature on Overall Efficiency of Combine Cycle Power Plant

    OpenAIRE

    Khan, M. N.; Tyagi, K. P.

    2010-01-01

    The gas turbine exhaust temperature, stack temperature and ambient temperature play a very important role during the predication of the performance of combine cycle power plant. This paper covers parametric analysis of effects of gas turbine exhaust temperature, stack temperature and ambient temperature on the overall efficiency of combine cycle power plant keeping the gas turbine efficiency as well as steam turbine efficiency constant. The results shows that out of three variables i.e. turbi...

  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. Comparison of sound, exhaust gas temperature and smoke opacity characteristics of methyl esters of vegetable oils blends

    Directory of Open Access Journals (Sweden)

    S. Prabhakar

    2011-10-01

    Full Text Available Experimental studies were conducted to evaluate the sound, exhaust gas temperature and smoke opacity characteristics of a single cylinder, four stroke engine fuelled with Vegetable oil methyl ester and its blends with standard diesel. Among different vegetable oils which can be used as alternate fuels, five vegetable oils, i.e., Nerium (Nerium oleander, Jatropha (Jatropha curcas, Pongamia (Pongamia pinnata, Mahua (Madhuca indica and Neem (Azadirachta indica oils were selected for analysis. Tests has been conducted using the fuel blends of 20%, 40%, 60% and 80% biodiesel with standard diesel, with an engine speed of 1800 rpm. It has found that the sound, exhaust gas temperature and smoke opacity characteristics of vegetable oil methyl ester and its diesel blends closely followed those of standard diesel.

  5. Comparison of sound, exhaust gas temperature and smoke opacity characteristics of methyl esters of vegetable oils blends

    OpenAIRE

    Prabhakar, S.; Annamalai, K.

    2011-01-01

    Experimental studies were conducted to evaluate the sound, exhaust gas temperature and smoke opacity characteristics of a single cylinder, four stroke engine fuelled with Vegetable oil methyl ester and its blends with standard diesel. Among different vegetable oils which can be used as alternate fuels, five vegetable oils, i.e., Nerium (Nerium oleander), Jatropha (Jatropha curcas), Pongamia (Pongamia pinnata), Mahua (Madhuca indica) and Neem (Azadirachta indica) oils were selected for analysi...

  6. Pt-loaded zeolites for reducing exhaust gas emissions at low temperatures and in lean conditions

    International Nuclear Information System (INIS)

    In this study, pure and platinum-loaded zeolites, ZSM-5, Beta, zeolite Y and Ferrierite, were examined for the reduction of NO with propene in lean conditions and at low temperatures. The studies were carried out by utilising the FT-IR technique both in determination of surface species as well as concentrations in the gas flow at reactor outlet. The maximum in the intermediate formation can be observed at the light-off temperatures over all studied catalyst materials. The maximum conversions of NO were reached with 1wt% Pt-loaded Beta and Y zeolites in excess oxygen. The lowest light-off temperatures of NO as well as propene can be detected also with Beta and Y zeolite catalysts

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

    Science.gov (United States)

    Bomela, Christian Loangola

    The overall industrial gas turbine efficiency is known to be influenced by the pressure recovery in the exhaust system. The design and, subsequently, the performance of an industrial gas turbine exhaust diffuser largely depend on its inflow conditions dictated by the turbine last stage exit flow state and the restraints of the diffuser internal geometry. Recent advances in Computational Fluid Dynamics (CFD) tools and the availability of computer hardware at an affordable cost made the virtual tool a very attractive one for the analysis of fluid flow through devices like a diffuser. In this backdrop, CFD analyses of a typical industrial gas turbine hybrid exhaust diffuser, consisting of an annular diffuser followed by a conical portion, have been carried out with the purpose of improving the performance of these thermal devices using an open-source CFD code "OpenFOAM". The first phase in the research involved the validation of the CFD approach using OpenFOAM by comparing CFD results against published benchmark experimental data. The numerical results closely captured the flow reversal and the separated boundary layer at the shroud wall where a steep velocity gradient has been observed. The standard k --epsilon turbulence model slightly over-predicted the mean velocity profile in the casing boundary layer while slightly under-predicted it in the reversed flow region. A reliable prediction of flow characteristics in this region is very important as the presence of the annular diffuser inclined wall has the most dominant effect on the downstream flow development. The core flow region and the presence of the hub wall have only a minor influence as reported by earlier experimental studies. Additional simulations were carried out in the second phase to test the veracity of other turbulence models; these include RNG k--epsilon, the SST k--o, and the Spalart-Allmaras turbulence models. It was found that a high resolution case with 47.5 million cells using the SST k--o turbulence model produced a mean flow velocity profile at the middle of the annular diffuser portion that had the best overall match with the experiment. The RNG k --epsilon, however, better predicted the diffuser performance along the exhaust diffuser length by means of the pressure recovery coefficient. These results were obtained using uniform inflow conditions and steady-state simulations. As such, the last phase of our investigations involved varying the inflow parameters like the turbulence intensity, the inlet flow temperature, and the flow angularity, which constitute important characteristics of the turbine blade wake, to investigate their impact on the diffuser design and performance. These isothermal CFD simulations revealed that by changing the flow temperature from 15 to 427°C, the pressure recovery coefficient significantly increased. However, it has been shown that the increase of temperature had no effects on the size of the reversed flow region and the thickness of the separated casing boundary layer, although the flow appears to be more turbulent. Furthermore, it has been established that an optimum turbulence intensity of about 4% produced comparable diffuser performance as the experiment. We also found that a velocity angle of about 2.5° at the last turbine stage will ensure a better exhaust diffuser performance.

  8. 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.

  9. Effects of exhaust temperature on helicopter infrared signature

    International Nuclear Information System (INIS)

    The effects of exhaust temperature on infrared signature (in 3–5 ?m 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 ?m 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. High Temperature Resistant Exhaust Valve Spindle

    DEFF Research Database (Denmark)

    Bihlet, Uffe Ditlev

    2014-01-01

    Transport by ship remains the most economical and environmentally friendly mode of transport with a very low weight specific CO2 footprint. Further increase of the fuel efficiency of large ships will results in a higher internal engine temperature. To allow this without compromising the reliability 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 Na2SO4 condense on the spindle, causing hot corrosion. Current industry standards can withstand service temperatures of up to 500°C for the spindle seat and 700°C for the spindle bottom. This project was tasked with increasing these temperatures 50°C each. Literature review as well as an in-situ corrosion test revealed that the most resistant alloy in such an environment is Alloy 657 (Ni-based, 49 wt% Cr, 1.5 wt% Nb). This alloy is suitable for the spindle bottom, but not for the spindle seat, as it is too weak. Thermodynamic calculations suggested that it was possible to modify the chemistry 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 by experimental laser cladding. Heat treatments proved that these alloys were precipitation hardenable, and that some of them reached high levels of hardness. Based on these results, five Ni-based alloys containing 35-45 wt% Cr and 4-6 wt% Nb were ordered, to narrow down the feasible alloy compositions. During the alloy development work, extensive microstructure quantification was performed, the results of which validated the predictive thermodynamical calculations. The heat treatment results showed that a relation exists between the solution treated microstructure and the mechanical properties. This lead to the design of the alloy Ni40Cr3.5Nb (Ni-based, 3.5 wt% Nb and 0.5 wt% Ti). This alloy is precipitation hardenable to the same level of hardness as Alloy 718, and laboratory testing suggests that it is suitable for application at service temperatures of 550°C.

  15. 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 team reforming reaction. Reforming of RME produced more hydrogen with higher fuel conversion efficiency compared to ULSD reforming

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

    Science.gov (United States)

    Friebe, Sebastian; Geppert, Benjamin; Caro, Jürgen

    2015-06-26

    A short-circuited PEM fuel cell with a Nafion membrane has been evaluated in the room-temperature separation of hydrogen from exhaust gas streams. The separated hydrogen can be recovered or consumed in an in situ olefin hydrogenation when the fuel cell is operated as catalytic membrane reactor. Without applying an outer electrical voltage, there is a continuous hydrogen flux from the higher to the lower hydrogen partial pressure side through the Nafion membrane. On the feed side of the Nafion membrane, hydrogen is catalytically split into protons and electrons by the Pt/C electrocatalyst. The protons diffuse through the Nafion membrane, the electrons follow the short-circuit between the two brass current collectors. On the cathode side, protons and electrons recombine, and hydrogen is released. PMID:26013958

  17. Polycyclic aromatic hydrocarbon emissions in diesel exhaust using gas chromatography-mass spectrometry with programmed temperature vaporization and large volume injection

    Science.gov (United States)

    Vieira de Souza, Carolina; Corrêa, Sergio Machado

    2015-02-01

    Diesel engines are significant sources of Polycyclic Aromatic Compounds (PAHs) in urban atmospheres. These compounds are widely known for their carcinogenic potential and mutagenic properties. In this study, a method was developed for the analysis of 16 priorities PAHs using gas chromatography-mass spectrometry (GC-MS) with programmable temperature vaporizer large volume injection (PTV-LVI), which allowed to be obtained detection limits below 2.0 ng mL-1. This method was evaluated in samples from stratified particulate matter and gas phase from the emissions of diesel vehicle employing diesel commercial S10 (sulfur 10 mg L-1) and B5 (biodiesel 5% v/v). A sampling system that does not employ exhaust products dilution was used to evaluate the PAHs gas-particle partition. Six PAHs were identified in extracts and gas-phase PAHs took percentage of 80% in the total PAHs emissions. The sampling system without dilution not caused a strong nucleation/condensation of the most volatile PAHs. PAHs size-particle distribution was found in higher levels in the accumulation mode.

  18. 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.)

  19. 40 CFR 1065.127 - Exhaust gas recirculation.

    Science.gov (United States)

    2010-07-01

    ...Exhaust gas recirculation. Use the exhaust gas recirculation (EGR) system installed with the engine or one that represents a typical in-use configuration. This includes any applicable EGR cooling...

  20. Ion Temperature Anisotropy across Reconnection Exhaust Jets

    Science.gov (United States)

    Hietala, H.; Drake, J. F.; Phan, T. D.; Eastwood, J. P.; McFadden, J. P.

    2014-12-01

    Magnetic reconnection redistributes energy by releasing magnetic energy into plasma kinetic energy - high speed bulk flows, heating, and particle acceleration. In the magnetotail, most of the released energy appears to go into ion heating. However, previous observations and simulations show that this heating is anisotropic with the plasma temperature parallel to the magnetic field generally increasing more than the perpendicular temperature. Simulations and theory indicate that this temperature anisotropy can balance part of the magnetic tension force that accelerates the jet, and may even exceed it leading to firehose instability.Here we report the results of a new study of ion temperature anisotropy in reconnection exhausts generated by anti-parallel reconnection. We have examined ARTEMIS dual-spacecraft observations of long-duration magnetotail exhausts at lunar distances in conjunction with Particle-In-Cell simulations. In particular, we have studied spatial variations in the ion temperature anisotropy across the outflows far away (>100 ion inertial lengths) from the X-line. A consistent pattern is found in both the spacecraft data and the simulations: whilst the total temperature profile across the exhaust is flat, near the exhaust boundaries the parallel temperature dominates. A consequence of this is that firehose threshold is greatly exceeded in a significant fraction of the exhaust. In contrast, the perpendicular temperature dominates at the neutral plane (|BX| < 0.1 B0), indicating that, despite the turbulence and the large distance to the X-line, particles undergo Speiser-like motion (rather than isotropization by scattering). We also analyse the characteristics of the particle distributions leading to these anisotropies at different distances from the mid-plane.

  1. Exhaust gas composition measurement. [liquid monopropellant rocket engine performance tests

    Science.gov (United States)

    1979-01-01

    The design, installation, checkout, and operation of an exhaust gas composition measurement system for collecting and analyzing the exhaust gas from a liquid monopropellant rocket engine are described. Design guidelines are given for the critical components of each portion of the system to provide an exhaust gas composition measurement which meets the performance criteria specified.

  2. 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.

  3. 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. ? Late injection cases had lower percentage of heat transfer exergy.

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

    Science.gov (United States)

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

    2008-05-27

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

  5. Critical topics in exhaust gas aftertreatment

    Energy Technology Data Exchange (ETDEWEB)

    Eastwood, Peter [Ford Motor Co., Research and Engineering Centre, Basildon (United Kingdom)

    2000-07-01

    Critical Topics in Exhaust Gas Aftertreatment reviews the major technical issues of the subject from an applications and systems perspective. It describes where today's aftertreatment fails, what new types of aftertreatment are currently under research, and how aftertreatment can most effectively by integrated into a vehicle's powertrain. The test is organised according to eight specific problems currently faced by the automotive industry, and which must be solved or circumvented if air quality goals are to be met. Much of the material has not appeared in monograph form before, and included is an extensive list of seen hundred references. (Author)

  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. Development of Exhaust Gas Driven Absorption Chiller-Heater

    Science.gov (United States)

    Inoue, Naoyuki; Endou, Tetsuya; Saito, Kiyoshi; Kawai, Sunao

    Waste heat from co-generation systems are usually recovered by hot water or steam, those are used to drive absorption refrigerators at cooling time, and those are used for heating via heat exchangers at heating time. However waste heat from micro gas turbines are discharged in the form of exhaust gas, it is simple that exhaust gas is directly supplied to absorption chiller-heaters. In the first report we studied cooling cycle, and this second paper, we evaluated various absorption heating cycles for exhaust gas driven absorption chiller-heaters, and adopted one of these cycles for the prototype machine. Also, we experimented with the prototype for wide range condition and got the heating characteristics. Based on the experimental data, we developed a simulation model of the static characteristics, and then studied how to increase the output by limited exhaust gas.

  8. 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

  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. Measuring Carbon Monoxide in Auto Exhaust by Gas Chromatography.

    Science.gov (United States)

    Jaffe, Dan; Herndon, Scott

    1995-01-01

    Presents a simple and reliable technique using commonly available equipment for monitoring carbon monoxide in automobile exhaust. The experiment utilizes a gas chromatograph and a thermal conductivity detector (TCD). (DDR)

  11. 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...

  12. Separation of carbon dioxide from offshore gas turbine exhaust

    International Nuclear Information System (INIS)

    The introduction of a CO2-tax in 1991 on offshore combustion of natural gas has led to an increased interest in both energy conservation and the possibility of separating CO2 from gas turbine exhaust. In this article a possible process will be presented. The result of the assessment is that an amine absorption process using membrane gas/liquid contactors in both the absorber and the desorber, in combination with a combined cycle power generation unit with 40% recycling of the exhaust gas and a CO2 compression unit, is best suited for CO2 removal among the options studied. 3 figs., 2 tabs

  13. Removing method for radon gas exhausted from nuclear fuel material

    International Nuclear Information System (INIS)

    A centrifugal separator is disposed in the midway of an exhaustion pipe of a nuclear fuel handling facility, and exhausted gases are sent into a rotational cylinder of the separator. Radon gases in the midway of exhaustion are separated from the exhaustion gases by the centrifugal force of the separator and caused to stagnate at the periphery of the circumferential wall of the rotational cylinder. At the same time, the exhaustion gases having the radon gases separated therefrom are exhausted from the periphery of a rotational shaft of the rotational cylinder. Then, the radon gases stagnated in the rotational cylinder are decayed depending on the half-decay time. With such procedures, the radon gases can be removed continuously without discharging them to the outside. Further, it is preferred that an exhaustion blower or the like for putting the inside of the nuclear fuel handing facility to a negative pressure is disposed as in a conventional case. Further, a plurality of centrifugal separators may be disposed to exhaustion pipes, to remove radon gases in the exhaust gases by a multi stage way. Radon gases can be removed in a saved space with no requirement for exchange of adsorbents or temperature control. (T.M.)

  14. 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.

  15. 500 CFM portable exhauster temperature and humidity analysis

    International Nuclear Information System (INIS)

    500 cfm portable exhausters will be utilized on single shell tanks involved in saltwell pumping. This will be done, in part, to remove flammable gases from the tank vapor space. The exhaust filter train, fan, stack, and associated instrumentation and equipment are mounted on a portable skid. The design analysis and basis for the skid system design are documented in reference 1. A pumped drainage collection system is being added to the existing portable exhausters. Additional equipment and instrumentation are also being added to the exhausters, including a vacuum pump cabinet and a generic effluent monitoring system (GEMS). The GEMS will provide sampling and monitoring capabilities. The purpose of this analysis is three fold. First, to determine the maximum saltwell tank vapor space temperature. Second, to determine an allowable exhauster inlet air temperature increase to ensure the humidity is less than 70%. Third, to assess potential adverse temperature effects to the continuous air monitor (CAM) sample head. The results of this analysis will be used to ensure that air stream temperatures in the portable exhausters are increased sufficiently to prevent condensation from forming on either the pre or HEPA filters without adversely effecting the CAM

  16. 40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.

    Science.gov (United States)

    2010-07-01

    ...New Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty...Exhaust gas sampling system; Otto-cycle vehicles not requiring...emissions in the exhaust of either Otto-cycle light-duty vehicles...temperature is not exceeded); or (iii) Using smooth wall duct...

  17. Emission Characteristics for Single Cylinder DI Diesel Engine with EGR (Exhaust Gas Recirculation System

    Directory of Open Access Journals (Sweden)

    Pratik G. Sapre

    2014-09-01

    Full Text Available This paper includes experimental investigations of various exhaust gas recirculation rates on engine emission characteristics like NOx, HC, CO, CO2, exhaust gas temperature by AVL gas meter. By passing exhaust gas from venturi meter and regulating it with EGR valve so as to find out its effect on critical NOx emission and other harmful HC,CO & NOx emission parameter. So to reduce such harmful gases exhaust gas recirculation is economical and effective method to control emission. We cant reduced it 100% but up to little bit extent we can reduce it from CI as well as in SI type of CI engine. Some external coupling technology like EGR of cold type installed with turbo intercooler, hydrogen, oxygen enriched air to displace fresh intake air volume and so reduced amount of oxygen in combustion chamber to control peak temperature of cylinder. in this paper we have also look toward some coal trapping method installed with dampener cause to break bond between NO at high temperature.

  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. 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.

  20. 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 ? and XO2 based on the sensor response? For IC engine applications, a chemistry model is required in order to predict ?, 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 ? 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)

  1. Study of recycling exhaust gas energy of hybrid pneumatic power system with CFD

    International Nuclear Information System (INIS)

    A hybrid pneumatic power system (HPPS) is integrated by an internal combustion engine (ICE), a high efficiency turbine, an air compressor and an energy merger pipe, which can not only recycle and store exhaust gas energy but also convert it into useful mechanical energy. Moreover, it can make the ICE operate in its optimal state of maximum efficiency; and thus, it can be considered an effective solution to improve greatly the exhaust emissions and increase the overall energy efficiency of the HPPS. However, in this system, the flow energy merger of both high pressure compressed air flow and high temperature exhaust gas flow of the ICE greatly depends on the merging capability of the energy merger pipe. If the compressed air pressure (Pair) at the air inlet is too high, smooth transmission and mixture of the exhaust gas flow are prevented, which will interfere with the operation condition of the ICE. This shortcoming is mostly omitted in the previous studies. The purpose of this paper is to study the effect of the level of Pair and the contraction of cross-section area (CSA) at the merging position on the flow energy merger and determine their optimum adjustments for a better merging process by using computation fluid dynamics (CFD). In addition, the CFD model was validated on the basis of the experimental data, including the temperature and static pressure of the merger flow at the outlet of the energy merger pipe. It was found that the simulatiorger pipe. It was found that the simulation results were in good agreement with the experimental data. The simulation results show that exhaust gas recycling efficiency and merger flow energy are significantly dependent on the optimum adjustment of the CSA for changes in Pair. Under these optimum adjustments, the exhaust gas recycling efficiency can reach about 83%. These results will be valuable bases to research and design the energy merger pipe of the HPPS.

  2. 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.

  3. Fiber metal acoustic material for gas turbine exhaust environments

    International Nuclear Information System (INIS)

    FELTMETAL fiber metal acoustic materials function as broad band acoustic absorbers. Their acoustic energy absorbance occurs through viscous flow losses as sound waves pass through the tortuous pore structure of the material. Exhaust gas noise attenuation requirements are reviewed. Their selection process for higher performance materials is discussed. A new FELTMETAL fiber metal acoustic material has been designed for use in gas turbine auxiliary power unit exhaust environments without supplemental cooling. The physical and acoustic properties of mesh supported fiber metal acoustic medium FM 827 are discussed. Exposure testing was conducted under conditions which simulated auxiliary power unit operation. Weight gain and tensile strength data as a function of time of exposure at 6500C (12020F) are reported. Fabrication of components with fiber metal acoustic materials is easily accomplished using standard roll forming and gas tungsten arc welding practices

  4. 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.

  5. 76 FR 58288 - International Maritime Organization Guidelines for Exhaust Gas Cleaning Systems for Marine...

    Science.gov (United States)

    2011-09-20

    ...Guidelines for Exhaust Gas Cleaning Systems for Marine Engines...guidelines for exhaust gas cleaning systems for marine engines...how to evaluate exhaust gas cleaning systems to determine under...and related material for our online docket must either be...

  6. Emission &Performance characteristics of single cylinder CI engine using cold EGR (Exhaust Gas Recirculation.

    Directory of Open Access Journals (Sweden)

    Avinash M.Wankhade

    2014-12-01

    Full Text Available In this paper we studied the effect of exhaust gas recirculation for reduction of harmful gases like NOx,CO2 etc. at a same time effects of cold EGR on performance of engine such as brake thermal efficiency, cylinder pressure, cylinder temperature exhaust temperature.etc Above parameter studied for stationary water cooled DI Diesel single cylinder engine by looking towards running(2014 and upcoming emission Norms. Also to incorporate technology to study effects of EGR on combustion temperature and so to reduce NOx by surveying emissions papers to have outlook of EGR Route system and important equipment that need to be furnished in further study in same project to have smooth and positive effects from performance side under study. Professor Avinash M.Wankhade et al found that while re-circulating exhaust gas it reduced about 65.26% of NOx which is improved results of Avinash Wankhade et al and Pratik Sapre et al under guidance of Dr.S.B.Thakare et al[ ].Use of EGR significantly reduced NO emissions at normal condition when passing 20% of EGR. The Particulate emissions increased as EGR rate is increased but we don’t deserve it so to vanish this effets further experiments can be done with blending diesel with fish methyl oil ester, sun flower oil methyl ester[14]. This reduces NOx as well HC.So Exhaust gas was recalculated in intake stroke and cooled by intercooler of partially cooled type via venturi meter.

  7. Process and device for cleaning furnace exhaust gas in a vitrification plant

    International Nuclear Information System (INIS)

    The furnace exhaust gas produced during vitrification is cleaned of carried over dust particles in an exhaust gas cleaning stage using a washing liquid. In order to achieve a simplified process for dosing and exhaust gas cleaning, radioactive fission product solution is taken from the feed container as the washing liquid and is transported to the head of the exhaust gas cleaning stage. The fission product solution noting as washing liquid is returned to the feed container after passing through the exhaust gas cleaning stage. The furnace exhaust gas of the vitrification plant is taken through the exhaust gas cleaning stage in counterflow. The invention also concerns a device to carry out this process. (orig./HP)

  8. An Experimental Study of Different Effects of EGR Rates on The Performance And Exhaust Emissions of The Stratified Charge Piston Direct Injection Compressed Natural Gas Engine

    OpenAIRE

    Saheed O. Wasiu; A. Rashid A. Aziz; Shaharin A. Sulaiman

    2011-01-01

    Exhaust Gas Recirculation (EGR) is one of the principal techniques used to control spark ignition NOX. A fraction of the exhaust gas is recycled through a control valve from the exhaust to the engine intake system. However, EGR has different effect on performance, combustion and emissions production that are difficult to distinguish such as increase of intake temperature, delay of Rate Of Heat Rrelease (ROHR), decrease of peak heat release, decrease in oxygen concentration etc. Therefor...

  9. 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 (Peter) 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.

  10. Improvement of a gas turbine cycle without exhaust gases based on graphical exergy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Koren, B.; Jin, H.; Ishida, M. [Tokyo Institute of Technology, Yokohama (Japan). Research Lab. of Resources Utilization

    1995-12-31

    This paper developed a gas turbine cycle with carbon dioxide as working fluid on the basis of a graphical exergy analysis (EUD - Energy Utilization Diagrams). Although the previous gas turbine cycle without exhaust gases has an advantage for recovering carbon dioxide, the EUD pointed out the problem and potential for improvement of this thermal system. For example, large exergy loss was found to occur in the heat exchange at low temperature. Furthermore, a saturation process into the gas turbine cycle without exhaust gases was introduced to utilize the low-level heat in the system. The improved system revealed the following characteristics: (a) thermal efficiency is increased from 43% to 49% (LHV); (b) the carbon dioxide exhaust in liquid form can be recovered; (c) there is low NO{sub x} formation due to no nitrogen in the combustor; (d) the water vapor in saturation process can be recovered; (e) the small amount of exhaust simplifies the removal of pollutants, like uncombusted fuel and other impurities. 7 refs., 5 figs., 1 tab.

  11. 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...

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

    Science.gov (United States)

    Isaksson, Juhani (Karhula, FI); Koskinen, Jari (Karhula, FI)

    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).

  13. 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.

  14. Parasitic load control system for exhaust temperature control

    Science.gov (United States)

    Strauser, Aaron D. (Washington, IL); Coleman, Gerald N. (Peterborough, GB); Coldren, Dana R. (Fairbury, IL)

    2009-04-28

    A parasitic load control system is provided. The system may include an exhaust producing engine and a fuel pumping mechanism configured to pressurize fuel in a pressure chamber. The system may also include an injection valve configured to cause fuel pressure to build within the pressure chamber when in a first position and allow injection of fuel from the pressure chamber into one or more combustion chambers of the engine when in a second position. The system may further include a controller configured to independently regulate the pressure in the pressure chamber and the injection of fuel into the one or more combustion chambers, to increase a load on the fuel pumping mechanism, increasing parasitic load on the engine, thereby increasing a temperature of the exhaust produced by the engine.

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

    OpenAIRE

    Hustad, Johan E.; Røkke, Petter E.

    2005-01-01

    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 amoun...

  16. 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.

  17. 78 FR 63015 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Science.gov (United States)

    2013-10-23

    ...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate...EPA also proposed adopting the gas turbine engine test procedures of the...Exhaust Emissions (New Aircraft Gas Turbine Engines) 0 3. Amend Sec....

  18. An experimental study on the effects of the thermal barrier plating over engine fuel consumption exhaust temperature and emissions

    Directory of Open Access Journals (Sweden)

    Hüseyin Gürbüz

    2014-01-01

    Full Text Available The aim of this study, the combustion chamber elements of a one-cylinder diesel engine which is air-cooled, single-cylinder, direct injection, 4-stroke and starter motor were plated with thermal barrier plating and tested with diesel fuel between the speeds of 1600 1/min to 3200 1/min and determined the effects of the thermal barrier plating on the engine exhaust gas temperature, emissions and fuel consumption. Increase in the temperature of the exhaust gas, decrease in HC and CO emissions that are harmful to the environment and living things and improvement in fuel consumption were observed.

  19. 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)

  20. 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)

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

    Science.gov (United States)

    Tomlinson, Leroy Omar (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)

    2002-01-01

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

  2. Effect of Fuel-Air Ratio, Inlet Temperature, and Exhaust Pressure on Detonation

    Science.gov (United States)

    Taylor, E S; Leary, W A; Diver, J R

    1940-01-01

    An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Results showed that for any given maximum pressure the maximum permissible end-gas temperature increased as the fuel-air ratio was increased. The tendency to detonate was slightly reduced by an increase in residual gas content resulting from an increase in exhaust backpressure with inlet pressure constant.

  3. 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...

  4. 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 formulation of a controller feedback multivariable is presented, designed with the combination of the technologies of fuzzy logic and neural networks with the purpose of improving the control of speed, power and temperature of the UTG. This proposed control is used in conjunction with the scheme of conventional control of the existent UTG, to integrate a strategy of control hybrid feedback. The control feedback is compound for a fuzzy inference system of multiple entrances and a left exit designed with entrance data and exit of the plant. The controller feed forward is compound for conventional controllers type PI in this type of units. With this strategy, the controller feedback provides a bigger contribution in the control sign the effort of the conventional controllers' PI control and the strong interaction that it exists among them diminishing. The controllers PI feed forward contribute a smaller control sign used for fine adjustments in the control sign. [Spanish] La demanda de energia electrica en Mexico ha obligado al sector electrico a estar en una busqueda constante de metodos y sistemas que, entre otros objetivos, mejoren continuamente la operacion de las centrales generadoras de energia electrica. Como parte de su mision, el Instituto de Investigaciones Electricas (IIE) ha promovido y apoyado la investigacion aplicada y el desarrollo tecnologico para mejorar los indices de seguridad, disponibilidad, confiabilidad, eficiencia y durabilidad de centrales generadoras mediante el desarrollo y la implantacion de grandes sistemas digitales de informacion y control. En la actualidad, dentro del esquema de generacion de energia electrica, las unidades turbogas (UTG) representan 7% de la generacion del sector electrico nacional [1]. Estas unidades se han convertido en el modo dominante de la nueva generacion electrica en los EE.UU, ya sea en ciclo simple o combinado. Lo anterior, es atribuible al menor costo de instalacion por kilowatt generado, a los programas de construccion mas cortos, a bajos niveles de emision de contaminantes y costos de operacion competitivo

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

    DEFF Research Database (Denmark)

    Andreasen, Morten; Marissal, Matthieu

    2014-01-01

    Concerned to push ships to have a lower impact on the environment, the International Maritime Organization are implementing stricter regulation of NOx and SOx emissions, called Tier III, within emission control areas (ECAs). Waste Heat Recovery Systems (WHRS) on container ships consist 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 with EGR is a potential way to improve system efficiency while reducing emissions. This paper investigates the feasibility of combining the two systems. EGR dilutes the fuel, lowering the combustion temperature and thereby the formation of NOx, to reach Tier III limitation. A double stage WHRS is set up to reach the highest possible combination of pressure and temperature, and adapted to Tier III by introducing two alternative superheaters. The system design is optimized and found capable of producing from 400 to 1900 kW, with a weighted average power of 958 kW. The consumption profile is found to significantly impact the weighted average power, while the operation distribution between Tier III and Tier II (outside ECAs) has a much smaller influence. Furthermore, it is found that the low pressure should be kept near minimum, while the optimum high pressure increases from 7 to 12 bar with the load. By increasing the efficiency of the overall system, the CO2 emissions can be reduced. The addition of a third cycle, used only in Tier III, is investigated. While increasing the total heat exchanger areas by approximately 40%, the cycle is found to increase the power production in Tier III operation by an average of 15%, and up to 50% at full load.

  6. Carbon Dioxide Emission Analysis of Chilled Water Production by Using Gas Turbine Exhaust Heat

    OpenAIRE

    Adzuieen Nordin; Mohd Amin Abd Majid

    2013-01-01

    Carbon dioxide from exhaust heat emission is one of the major contributorsto the environmental pollutant in power generation plants. This problem could be addressed if the emitted exhaust heat is recovered. In cogeneration plant, the exhaust heat from the gas turbine is used to generate steam usingHeat Recovery Steam Generator. The steam from Heat Recovery Steam Generator is then used for chilled water generation in Steam Absorption Chillers by absorption process. This study analyzed the tota...

  7. 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.

  8. Exhaust Gas Heat Recovery for C.I Engine-A Review

    OpenAIRE

    Baleshwar Kumar Singh,; Dr. Nitin Shrivastava

    2014-01-01

    The focus of the study is to review the modern changes and technologies on waste heat recovery of exhaust gas from internal combustion engine. These include the thermoelectric generator, turbocharger, exhaust gas through I.C engine. Due to the total heat supplied to the engine in the form of fuel around 30-40%, heat is converting in to the use full mechanical work and residual parts of the wastage heat 60-70% as friction, exhaust gas and engine cooling system. Waste heat relea...

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

    International Nuclear Information System (INIS)

    The conversion efficiency of a catalytic converter, mounted on a vehicle equipped with a 2.8 l 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 x conversion efficiency remains nearly constant regardless of BMEP and rpm; (v) except for idle, the NO 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 modficiency 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

  10. 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)

  11. 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. (Menlo Park, CA); Merkel, Timothy C. (Menlo Park, CA); Baker, Richard W. (Palo Alto, CA)

    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.

  12. Experimental investigations of an annular diffuser of the gas turbine exhaust hood

    Energy Technology Data Exchange (ETDEWEB)

    Zaryankin, A.E.; Zatzepin, M.F.; Jesionek, K.J.

    1998-07-01

    Gas-turbine exhaust-hood losses depend on the relative dimensions of the last stage of the turbine and the configuration of the gas outlet system. The knowledge of these relationships makes it possible to determine optimal turbine-exhaust-hood overall dimensions for which high values of the static-pressure recovery coefficient can be obtained. Only a part of an experiment program concerning the effect of the back-casing wall of the exhaust-hood arrangement is presented here. (orig.)

  13. [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

  14. Concepts for exhaust gas purification. Low emissions despite high pollutant input; Konzepte zur Abgasreinigung. Tiefe Emissionen trotz hohem Schadstoff - Input

    Energy Technology Data Exchange (ETDEWEB)

    Frey, R. [Von Roll Inova, Zuerich (Switzerland)

    2007-07-01

    This paper presents different exhaust gas purification concepts and compares them with respect to investment and operating costs: quasi-dry process (Turbosorp) with lime hydrate (e.g. AVS Zorbau); quasi-dry process with a downstream scrubber (e.g. TREA Breisgau); dry sorption with sodium carbonate (combined with a downstream low-temperature catalyst, e.g. MVA Zistersdorf); and wet scrubber with upstream spray dryer (e.g. HVC Alkmaar, 4th line).

  15. 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.

  16. 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)

  17. Reduction of low temperature engine pollutants by understanding the exhaust species interactions in a diesel oxidation catalyst.

    Science.gov (United States)

    Lefort, I; Herreros, J M; Tsolakis, A

    2014-02-18

    The interactions between exhaust gas species and their effect (promotion or inhibition) on the light-off and activity of a diesel oxidation catalyst (DOC) for the removal of pollutants are studied, using actual engine exhaust gases from the combustion of diesel, alternative fuels (rapeseed methyl ester and gas-to-liquid fuel) and diesel/propane dual fuel combustion. The activity of the catalyst was recorded during a heating temperature ramp where carbon monoxide (CO) and hydrocarbon (HC) light-off curves were obtained. From the catalyst activity tests, it was found that the presence of species including CO, medium-heavy HC, alkenes, alkanes, and NOx and their concentration influence the catalyst ability to reduce CO and total HC emissions before release to the atmosphere. CO could inhibit itself and other species oxidation (e.g., light and medium-heavy hydrocarbons) while suffering from competitive adsorption with NO. Hydrocarbon species were also found to inhibit their own oxidation as well as CO through adsorption competition. On the other hand, NO2 was found to promote low temperature HC oxidation through its partial reduction, forming NO. The understanding of these exhaust species interactions within the DOC could aid the design of an efficient aftertreatment system for the removal of diesel exhaust pollutants. PMID:24450781

  18. Suicide by carbon monoxide from car exhaust-gas in Denmark 1995-1999

    DEFF Research Database (Denmark)

    Thomsen, Asser H; Gregersen, Markil

    2006-01-01

    In the period 1995-1999 there were 388 car exhaust-gas suicides in Denmark. Of these 343 (88.4%) were men and 45 (11.6%) were women, the average age being 47 years. The car exhaust-gas suicides made up 9.3% of all suicides in Denmark in the period. The corresponding rate was 11.7% for men and 3.7% for women. In rural areas a larger part of all suicides were committed with car exhaust-gas compared to the more densely populated areas. Mental disease was diagnosed in 124 (32.0%) cases. A suicide note was found in 165 (42.5%) cases. A hose was fitted to the exhaust pipe in 334 (86.1%) cases. Of these the 234 (60.3%) occurred outside, typically in a forest area, while 76 (19.6%) occurred in a closed garage. All the 54 (13.9%) cases with no hose fitted to the exhaust pipe occurred in a garage. Seven (1.8%) victims were found in a burning or burnt-out car, where the following investigation revealed that it was actually a car exhaust-gas suicide. Carboxyhemoglobin was measured in 26 (6.7%) victims. In two of these victims no carboxyhemoglobin was found, as they had survived for some time after the poisoning. The average saturation of the remaining victims was 67%, the lowest saturation being 20% and the highest being 84%. In the period 1969-1987 the number of car exhaust-gas suicides in Denmark increased from 50 to approximately 190 per year and the rate of car exhaust-gas suicides compared to all suicides increased from approximately 5% to approximately 13%. In 1987-1999 these figures decreased from approximately 190 to 63 per year and from 13% to approximately 8%. During these 30 years the number of passenger cars in Denmark doubled, which explains the increase in car exhaust-gas suicides during 1969-1987. A possible explanation for the decrease in 1987-1999 is the introduction of the catalytic converter, which was made mandatory in 1990. We anticipate that car exhaust-gas suicides will continue to decrease in numbers, as more cars are equipped with catalytic converters.

  19. Diesel engine exhaust gas recirculation--a review on advanced and novel concepts

    International Nuclear Information System (INIS)

    Exhaust gas recirculation (EGR) is effective to reduce nitrogen oxides (NOx) from Diesel engines because it lowers the flame temperature and the oxygen concentration of the working fluid in the combustion chamber. However, as NOx reduces, particulate matter (PM) increases, resulting from the lowered oxygen concentration. When EGR further increases, the engine operation reaches zones with higher instabilities, increased carbonaceous emissions and even power losses. In this research, the paths and limits to reduce NOx emissions from Diesel engines are briefly reviewed, and the inevitable uses of EGR are highlighted. The impact of EGR on Diesel operations is analyzed and a variety of ways to implement EGR are outlined. Thereafter, new concepts regarding EGR stream treatment and EGR hydrogen reforming are proposed

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

    Directory of Open Access Journals (Sweden)

    Ralf Moos

    2009-09-01

    Full Text Available 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 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.

  1. Carbon Dioxide Emission Analysis of Chilled Water Production by Using Gas Turbine Exhaust Heat

    Directory of Open Access Journals (Sweden)

    Adzuieen Nordin

    2013-12-01

    Full Text Available Carbon dioxide from exhaust heat emission is one of the major contributorsto the environmental pollutant in power generation plants. This problem could be addressed if the emitted exhaust heat is recovered. In cogeneration plant, the exhaust heat from the gas turbine is used to generate steam usingHeat Recovery Steam Generator. The steam from Heat Recovery Steam Generator is then used for chilled water generation in Steam Absorption Chillers by absorption process. This study analyzed the total estimated amount of CO2 released to the environment due to chilled water production by using gas turbine exhaust heat. University Teknologi PetronasMalaysia cogeneration system is used as a case study. The energy balance principlewas adopted for the analysis. Results indicate that approximately 44% of CO2is avoided from being released to the environment by this process.

  2. 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

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

    Science.gov (United States)

    Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

    2002-01-01

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

  4. Identification, structure elucidation, and synthesis of volatile compounds in the exhaust gas of food factories.

    Science.gov (United States)

    Nagorny, S; Francke, W

    2005-01-01

    Our investigations deal with the identification and synthesis of volatile, odoriferous compounds contained in the exhaust gas of food factories and on the biodegradation of alkylpyrazines. Collection of odour emissions samples was performed with a gas sampler equipped with filter tubes containing the styrene-polymer SuperQ. After elution with solvents of different polarity, the extracts were analysed by GC/MS and chemical microreactions. Proposed structures were verified by comparison of analytical data with those of synthetic reference samples. Major components in the exhaust gas of a fat finishing factory were found to be aliphatic aldehydes, strongly dominated by hexanal. The identification of 1,2,3,3-tetramethylcyclohexene shows that for structural proof of target compounds the use of authentic reference samples is indispensable. In the exhaust gas from a chocolate factory, several carbonyl compounds and alkylated pyrazines could be identified. Biodegradation of the latter starts with hydrogenation at the nucleus. PMID:16154731

  5. 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.)

  6. Catalytic study of SOFC electrode materials in engine exhaust gas atmosphere

    OpenAIRE

    Briault, Pauline; Rieu, Mathilde; Laucournet, Richard; Morel, Bertrand; Viricelle, Jean-paul

    2013-01-01

    A single chamber solid oxide fuel cell (SC-SOFC) is a device able to produce electricity from a mixture of hydrocarbons and oxidant. An innovative application of this system would be to recover energy from exhaust gas of a thermal engine. This paper presents a study of stability and catalytic behaviour of electrode materials composing the cell in a mixture of hydrocarbons (propane, propene), oxygen, carbon monoxide, carbon dioxide, hydrogen and water corresponding to a composition of exhaust ...

  7. Diesel emission reduction using internal exhaust gas recirculation

    Science.gov (United States)

    He, Xin (Denver, CO); Durrett, Russell P. (Bloomfield Hills, MI)

    2012-01-24

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

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

    Science.gov (United States)

    Pak, Pyong Sik

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

  9. An Experimental Investigation of an Exhaust-gas-to-air Heat Exchanger for Use on Jet-stack-equipped Engines

    Science.gov (United States)

    Stalder, Jackson R; Spies, Ray J , Jr

    1948-01-01

    Tests were made to determine the loss in exhaust-jet thrust and engine power resulting from the insertion of an exhaust-gas-to-air heat exchanger in a jet-type exhaust stack of an aircraft engine. The thermal performance of the heat exchanger was also determined.

  10. Performance analysis for the characteristics of hybrid type absorption chiller operated by exhaust gas and hot water

    International Nuclear Information System (INIS)

    The characteristics of hybrid type absorption chiller are studied numerically to use a waste hot water and exhaust hot gas effectively. As the partial load decreases, COP decreases but COPf increases. It is because of the system more rely upon the single effect cycle compare to the double effect cycle. So the consumption ratio of fuels increase and the save ratio decrease as the partial load decreases. For the same reason, as the inlet temperature and flow rate of hot water increase COP decreases but COPf increases. As the inlet temperature of the hot gas increase, COPf increases. It is because of the consumption ratio of fuels decreases as the inlet temperature of the hot gas increase.

  11. The effect of heat transfer on performance of the Diesel cycle and exergy of the exhaust gas stream in a LHR Diesel engine at the optimum injection timing

    International Nuclear Information System (INIS)

    In this study, a Diesel cycle analysis taking combustion and heat transfer into account on performance has been performed. The effect of heat transfer is analysed in terms of design parameters such as compression ratio and cut-off ratio. The effects of heat transfer from the cylinder on exhaust temperature were also investigated for different heat transfer and combustion modes. It was observed that the work output and exhaust temperature proportionally increase with the decrease of heat transfer for a fixed combustion rate and cut-off ratio. In the experimental study, it was found that the minimum fuel consumption in the LHR engine compared to the standard (STD) engine was obtained with a 4 deg. crank angle (CA) retardation of the injection timing from the 38 deg. (CA). The decrease in specific fuel consumption at this injection timing reached 6%, and the increase in brake thermal efficiency was 2%. The exhaust temperature of the LHR Diesel engine with the injection timing of 38 deg. CA was 10.8% higher than that of the STD engine, whereas, the increase in the temperature reached 22.8% at 34 deg. CA. Thus, as a consequence of its great potential for optimisation of system performance, a comparative exergy analysis has been performed with the purpose of calculating the amount of available energy of the exhaust gas stream at the optimum injection timing (34 CA) for the LHR engine. While the maximum amount of available energy in the LHR engine exhaust gas stream with thethe LHR engine exhaust gas stream with the injection timing of 38 deg. CA was 13.45%, the increase at the optimum injection timing of 34 deg. CA was found to reach 38%. It was concluded that the exhaust gas stream of a low heat rejection (LHR) Diesel engine is the most important source of available energy, which must be recovered via a secondary heat recovery system

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

    DEFF Research Database (Denmark)

    Hansen, Jakob Mahler; Blanke, Mogens

    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 analysis of the highly non-linear dynamics. Control architectures are investigated and performance in terms of disturbance rejection and reference tracking are investigated under model uncertainty. Classical feed-forward and feedback controller designs are investigated using classical and Quantitative Feedback Theory (QFT) designs. Validation of the controller is made on the model with focus on disturbance reduction ability.

  13. Analysis of an ethanol-fuelled solid oxide fuel cell system using partial anode exhaust gas recirculation

    Science.gov (United States)

    Saebea, Dang; Patcharavorachot, Yaneeporn; Arpornwichanop, Amornchai

    2012-06-01

    This paper presents an analysis of a solid oxide fuel cell (SOFC) system integrated with an ethanol reforming process. The recycling of the anode exhaust gas in the integrated SOFC system is considered to improve its performance. The results indicate that under the same operating conditions, the SOFC system operated with the recycle of the anode exhaust gas has higher electrical and thermal efficiencies than a non-recycling SOFC system. The required conditions to prevent carbon formation in the ethanol reformer are also examined. When the SOFC system with anode exhaust gas recycling is operated at a higher recirculation ratio and fuel utilization, the carbon formation can be reduced, which in turn decreases the reformer operating temperature. However, the recirculation ratio has to be carefully selected because an increase in the recirculation ratio has an adverse impact on the electrical efficiency of the SOFC system. In addition, the results show that the electrical efficiency depends on the fuel utilization of the SOFC. At low fuel utilization (0.5-0.6), the electrical efficiency increases as the recirculation ratio increases. In contrast, when the SOFC is operated at a higher fuel utilization (>0.6), an increase in the recirculation ratio results in a decrease in the electrical efficiency.

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

    DEFF Research Database (Denmark)

    Åberg, Andreas; Hansen, Thomas Klint

    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 the whole catalytic exhaust system would be beneficial towards this goal. A methodology for developing a modular model capable of simulating a system consisting of several sub systems is presented. The methodology describes the steps the user should take to go from problem formulation to the final modular model. Four different models in the automotive diesel exhaust gas cleaning system are presented briefly. Based on the presented methodology, it is discussed which changes are needed to the models to create a modular model of the whole catalytic system.

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

    Science.gov (United States)

    Gaborieau, Cécile; Sommier, Alain; Toutain, Jean; Anguy, Yannick; Crepeau, Gérald; Gobin, Benoît

    2012-04-01

    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.

  16. 40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.

    Science.gov (United States)

    2010-07-01

    ...Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled... Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty...Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled...under this option); or (iii) Omitting the duct and...

  17. HPLC analysis of aldehydes in automobile exhaust gas: Comparison of exhaust odor and irritation in different types of gasoline and diesel engines

    International Nuclear Information System (INIS)

    This study investigated high performance liquid chromatography (HPLC) to identify and measure aldehydes from automobile exhaust gas. Four aldehydes: formaldehyde (HCHO), acetaldehyde (CH3CHO), acrolein (H2C=CHCHO) and propionaldehyde (CH3CH2CHO) and one ketone, acetone (CH3)2CO are separated. The other higher aldehydes in exhaust gas are very small and cannot be separated. A new method of gas sampling, hereafter called bag sampling in HPLC is introduced instead of the trapping gas sampling method. The superiority of the bag sampling method is its transient gas checking capability. In the second part of this study, HPLC results are applied to compare exhaust odor and irritation of exhaust gases in different types of gasoline and diesel engines. Exhaust odor, irritation and aldehydes are found worst in direct injection (DI) diesel engines and best in some good multi-point injection (MPI) gasoline and direct injection gasoline (DIG) engines. Indirect injection (IDI) diesel engines showed odor, irritation and aldehydes in between the levels of MPI gasoline, DIG and DI diesel engines

  18. 40 CFR 86.511-90 - Exhaust gas analytical system.

    Science.gov (United States)

    2010-07-01

    ...CO and CO2 , Figure F90-3, consists of a flame ionization detector (FID) (heated (235°±15 °C (113...of a gas chromatograph (GC) equipped with a flame ionization detector. The analysis for formaldehyde is...

  19. CHEMICAL COMPOSITION OF EXHAUST PARTICLES FROM GAS TURBINE ENGINES

    Science.gov (United States)

    A program was conducted to chemically characterize particulate emissions from a current technology, high population, gas turbine engine. Attention was focused on polynuclear aromatic compounds, phenols, nitrosamines and total organics. Polynuclear aromatic hydrocarbons (PAH) were...

  20. 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

  1. System acceptance and operability test report for the RMCS exhauster C on flammable gas tanks

    International Nuclear Information System (INIS)

    This test report documents the completion of acceptance and operability testing of the rotary mode core sampling (RMCS) exhauster C, as modified for use as a major stack (as defined by the Washington State Department of Health) on flammable gas tanks

  2. Application of a power recovery system to gas turbine exhaust gases

    International Nuclear Information System (INIS)

    This paper discusses the application of a power recovery system to recover waste heat from the exhaust gases of gas turbines and convert this energy into shaft horsepower. Also discussed are power cycles, selection of power fluid, equipment selection, and application of the power recovery system to various gas turbines. Several charts and tables are included: process flow diagram, cycle efficiencies, curve for estimating recoverable horsepower

  3. Exhaust Gas Heat Recovery for C.I Engine-A Review

    Directory of Open Access Journals (Sweden)

    Baleshwar Kumar Singh,

    2014-11-01

    Full Text Available The focus of the study is to review the modern changes and technologies on waste heat recovery of exhaust gas from internal combustion engine. These include the thermoelectric generator, turbocharger, exhaust gas through I.C engine. Due to the total heat supplied to the engine in the form of fuel around 30-40%, heat is converting in to the use full mechanical work and residual parts of the wastage heat 60-70% as friction, exhaust gas and engine cooling system. Waste heat release in the form of fumes in environment through I.C engine, which also includes the exhaust gases. The side effects are global warming, greenhouse effects and entropy increases etc. Therefore, it is required to use the waste heat in to useful work. The recovery of waste heat not only conserves fossil fuel but also control the environment pollution. Therefore, main objective of this paper is to evaluate (waste heat recovery system technology based on the total waste heat converted into the useful mechanical work and possible methods to recovery of the waste heat from I.C engine. As a result, waste heat recovery from the I.C engines and utilization shall be remain best technique in future automobile application save the fuel and protect the environment.

  4. 40 CFR 86.509-90 - Exhaust gas sampling system.

    Science.gov (United States)

    2010-07-01

    ...satisfies the first condition by metering at a constant temperature...enough to completely eliminate water condensation in the dilution and sampling systems. Control of water condensation with methanol-fueled...also be required to eliminate water condensation when testing...

  5. 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.

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

    Science.gov (United States)

    Orosa, John; Montgomery, Matthew

    2014-02-11

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

  7. 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.

  8. Measurement of gas-phase polycyclic aromatic hydrocarbons (PAH) in gasoline vehicle exhaust

    International Nuclear Information System (INIS)

    Polycyclic aromatic hydrocarbons (PAH) are emitted at low levels from most combustion sources including motor vehicles. Extensive studies have been carried out in the past on the identification and quantitation of PAH in particular matter, primarily from diesel vehicles; however, only limited data are available on gas phase emissions from motor vehicles. Gas phase emissions are important from both a health perspective and because of their higher chemical reactivity during atmospheric transport. A method was sought to allow the authors to measure gas phase PAH in diluted vehicle exhaust over the relatively short collection times permitted during the U. S. Environmental Protection Agency (EPA) Urban Dynamometer Driving Schedule (UDDS) or Federal Test Procedure (FTP). In this paper, the authors describe their results on the development of a method using adsorption/thermal desorption with Tenax solid absorbent for the analysis of PAH and PAH derivatives in dilute vehicle exhaust

  9. 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 absod 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 approximately US$ 20.9 million, with a payback period of 1 year. This study highlights the significant economical and environmental benefits that could be achieved through implementation of the proposed integrated cogeneration scheme in NGPPs, particularly in elevated ambient temperature and humidity conditions such as encountered in Middle East facilities.

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

    DEFF Research Database (Denmark)

    Lieke, Kirsten Inga; RosenØrn, Thomas

    2013-01-01

    This work provides insight into the morphology and mixing state of submicron particles in diesel exhaust from a ship engine with an exhaust gas recirculation scrubber. Particles from this low-speed ship engine on test bed were collected using a microiner-tial impactor with transmission electron microscopy (TEM) grids on two stages. Micro- and nanostructural characteristics of sin-gle particles were studied by TEM. Image analysis was carried out on overview and high-resolution images, revealing influence of the exhaust gas treatment (scrubber) on the particle morphology and mixing state. Soot agglomerates were found to be collapsed after scrubber, reflected by their change in fractal dimension (fly) from 1.88 to 2.13. Soot was predominantly found internally mixed with other components, with a higher degree of internal mix-ing observed after scrubber. Soot nanostructural characteristics on the near atomic scale such as layer distance, lamella length, and tortuosity were not observed to be influenced by the scrub-ber. We also found that particles in the size range between 30 and 50 nm, which were abundant in the exhaust before and after scrubber, were not graphitic soot. Furthermore, we found indications that these particles are composed of other crystalline material (salts).

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

    DEFF Research Database (Denmark)

    Lieke, Kirsten Inga; Rosenorn, Thomas

    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 microinertial impactor with transmission electron microscopy (TEM) grids on two stages. Micro- and nanostructural characteristics of single particles were studied by TEM. Image analysis was carried out on overview and high-resolution images, revealing influence of the exhaust gas treatment (scrubber) on the particle morphology and mixing state. Soot agglomerates were found to be collapsed after scrubber, reflected by their change in fractal dimension (D-f ) from 1.88 to 2.13. Soot was predominantly found internally mixed with other components, with a higher degree of internal mixing observed after scrubber. Soot nanostructural characteristics on the near atomic scale such as layer distance, lamella length, and tortuosity were not observed to be influenced by the scrubber. We also found that particles in the size range between 30 and 50nm, which were abundant in the exhaust before and after scrubber, were not graphitic soot. Furthermore, we found indications that these particles are composed of other crystalline material (salts). Copyright 2013 American Association for Aerosol Research

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

    Science.gov (United States)

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

    2012-06-01

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

  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. Consideration of a new cleanup system to remove tritium from an exhaust gas

    International Nuclear Information System (INIS)

    A tritium cleanup system for application to exhaust gases discharged from the Large Helical Device (LHD) has been developed at the National Institute for Fusion Science. The system is distinguished from conventional systems in that tritium which is in various chemical forms in the exhaust gas is removed as hydrogen molecules. The system basically consists of three main components, a hydrogen separator, a decomposition-processing vessel, and a hydrogen-absorbing vessel. We have been developing the decomposition-processing vessel over the last few years. In the present study, the performance of the tritium cleanup system was examined by computer-based simulation. We assumed that the gas for processing was made up of hydrogen, methane, and helium. To monitor the removal of tritium from the exhaust gas, we examined the partial pressures of the respective components during processing. The speed of processing was shown to gradually decrease with increasing proportions of methane. The curve for the partial pressure of hydrogen clearly bends at two elapsed times; one when a cycle of processing has been completed, and the other when helium became the dominant determinant of the speed with which the circular pump drove the gas flow. The first bent disappeared when the proportion of methane was lager than 80 %. The second bend gradually moved to the right along the X-axis as the proportion of methane increased. The time interval between the first and second bends obviously lengtthe first and second bends obviously lengthened as the proportion of methane grew

  15. 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 in which all gaseous compounds are absorbed before particles are collected, and in which the volatile compounds are derivatized, would improve the precision and the accuracy of the data.

  16. Study on using acetylene in dual fuel mode with exhaust gas recirculation

    International Nuclear Information System (INIS)

    Interest in employing gaseous fuels to internal combustion (IC) engines whether for stationary or mobile automotive applications has gained importance because of the economical, sustainable and environmental technical features associated with their usage. However, the incidence of preignition and knock remains a significant barrier in achieving their optimum performance potential. With the advent of latest technologies, the above barriers are eliminated. One such technique is timed manifold injection (TMI) of the gaseous fuel, which is controlled electronically to precisely monitor the induction of fuel to overcome the preignition problem in the intake. In the present investigation, acetylene was injected in the intake manifold in a single cylinder diesel engine, with a gas flow rate of 240 g/h, start of injection time is 10o aTDC and 90o CA (9.9 ms) duration, operated in dual fuel mode. In order to decrease the NOx emissions from acetylene-diesel engine, cooled EGR was employed. The cylinder pressure, brake thermal efficiency and emissions such as NOx, smoke, CO, HC, CO2 and exhaust gas temperature were studied. Dual fuel operation with acetylene induction coupled with cooled EGR results in lowered NOx emissions and improved part load performance. -- Highlights: ? Acetylene was tried in SI engines, but due to backfire further research was hindered as an alternative fuel. ? But it is not tried in CI engine. Timed manifold injection was tried in diesel engine in the present work to combat backfire. ? Author was successful in running the diesel engine in dual fuel mode. ? 21% maximum diesel replacement was achieved. Author is confident that acetylene will be commercialised as a fuel for diesel engine in future.

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

    DEFF Research Database (Denmark)

    Hansen, Jakob Mahler; Zander, Claes-Göran

    2013-01-01

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

  18. 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) Diesel engine soot and NOx emission modelling. (orig)

  19. Modelling and observation of exhaust gas concentrations for diesel engine control

    OpenAIRE

    Blanco Rodriguez, David

    2013-01-01

    The dissertation covers the problem of the online estimation of diesel engine exhaust concentrations of NOx and '1. Two information sources are utilised: ¿ on-board sensors for measuring NOx and '1, and ¿ control oriented models (COM) in order to predict NOx and '1. The evaluation of the static accuracy of these sensors is made by comparing the outputs with a gas analyser, while the dynamics are identified on-board by perform- ing step-like transitions on NOx and '1 afte...

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

    OpenAIRE

    RANBIR SINGH; SAGAR MAJI

    2012-01-01

    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 la...

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

    OpenAIRE

    Charles, M.; Agbomadzi, S. P.

    2010-01-01

    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...

  2. Metal oxide coatings for piezoelectric exhaust gas sensors

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.T.; Cernosek, R.W.

    1996-06-01

    We have deposited ZrO{sub 2}, TiO{sub 2}, and SnO{sub 2} films on ST-cut quartz surface acoustic wave (SAW) devices via sol-gel techniques. The films range from 100 to 300 nm thick and have porosities after calcination at 300{degrees}C that range from 82-88 % for ZrO{sub 2}, 77-81% for TiO{sub 2}, and 57-66% for SnO{sub 2}. In all cases, we have varied the synthesis and processing parameters over a wide range to optimize film properties: metal ion concentration (0.05-1.0 M), the H{sub 2}O:metal ratio (0.3-5.3), the acid concentration in the sol (0.02-0.7 M), the modifier ligand:metal ratio (r = 0.0-1.0), the processing conditions (100-900{degrees}C). The modifier ligand, triethanolamine (TEA), is added to each solution to allow multilayer films to be made crack free. The multilayer films are studied by optical microscopy, ellipsometry, X-ray diffraction, and N{sub 2} sorption. Preliminary high temperature frequency response measurements to target gases, such as, H{sub 2}, NO, NO{sub 2}, and propylene indicate limited sensitivity for the configurations tested.

  3. Mining utilization of residues of exhaust gas cleaning from waste incinerators; Bergtechnische Verwertung von Abgasreinigungsrueckstaenden aus Verbrennungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Werthmann, Rainer [K+S Entsorgung GmbH, Kassel (Germany). Abfallchemie und Zulassungen

    2013-03-01

    The exhaust gas purification of a household incinerator or a substitute fuel power plant intends to remove dust, heavy metal compounds and acid harmful gases from the exhaust gas in order to comply with the immission-control legal limits. The particulate matter contains volatile heavy metal chlorides which precipitate as a solid matter. The enhanced amount of water-soluble salts is conspicuous. The concentration of soluble components is limited to 10,000 mg/L in the 1:10 eluate due to the landfill regulation. Thus, the residues of exhaust gas cleaning are predestined for an underground waste disposal in salt mines. Under this aspect, the author of the contribution under consideration reports on the mining utilization of residues of exhaust gas cleaning from waste incinerators.

  4. Properties of rapidly solidified Fe-Cr-Al ribbons for the use as automotive exhaust gas catalyst substrates

    International Nuclear Information System (INIS)

    Metallic honeycomb structures are used as catalyst substrates in automotive exhaust gas systems. This application requires an outstanding corrosion resistance at elevated temperatures of the substrate material. Technical improvements can be achieved by the use of rapid solidification technology for the production of the Fe-Cr-Al ribbons since the Al content can be substantially increased from about 5% Al in the conventionally rolled material to about 12% Al in the rapid solidified ribbon. As a result the lifetime of the ribbon in a higher-temperature corrosion environment is drastically increased. In addition the scale/metal adherance is improved. The impediment of recrystallization in the rapidly solidified ribbons prevents an embrittlement even in carbonizing atmospheres. (orig.)

  5. Investigation into relative temperature measurement of pulsed constrained gas flow using passive acoustic means

    OpenAIRE

    Moss, Joseph Brian

    2011-01-01

    The requirement to measure the real time, dynamic temperature of exhaust system gases is becoming more and more important in the areas of aeronautics, automotive (cars, trucks, etc), marine and industrial/environmental applications, in particular on a cycleby-cycle (CBC) basis. Monitoring exhaust gas temperatures of any power-plant can give important diagnostic information for the monitoring of fuel mixture, combustion efficiency etc. This 'diagnostic' information can be used to help 'd...

  6. 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

  7. 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

  8. 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)

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

    Science.gov (United States)

    Serres, Nicolas (Epinal, FR)

    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.

  10. Poisoning of automotive exhaust gas catalyst components. The role of phosphorus in the poisoning phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Kroeger, V.

    2007-07-01

    The aim of this thesis project was to gain new knowledge on the effect of phosphorus on the catalytic activity and characteristics of automotive exhaust gas catalyst components. The simultaneous roles of phosphorus and calcium were also studied. The first test series of powdery catalyst samples contained Rh and oxide (Test series (1) and the second, Pt and oxide or ZSM-5 (Test series 2). The catalysts were analyzed when fresh and after two ageing and phosphorus poisoning procedures developed in this work. The procedures consisted of adding poison via impregnation in an aqueous solution (for Test series 1) and in the gaseous phase under hydrothermal conditions (for Test series (2). The poison compounds formed and the changes in the washcoat were studied by using physisorption analyses, SEM, TEM, XRD, and FTIR-ATR. The poison content of the samples was determined by ICP-OES and XRF. Laboratory-scale activity measurements were done to investigate the catalytic activity. Thermodynamic calculations were used to obtain information about ageing conditions and phosphorus compounds formed during ageing. Phosphorus decreased the catalytic activity and the characteristic surface areas of the catalysts. Addition of calcium to a phosphorus-poisoned catalyst was found to have even a regenerating effect on the catalysts' activity. The poisoning methods developed in this study resulted in the same phosphorus compounds as can be found in vehicle-aged catalysts. Phosphorus was identified as cerium, zirconium, aluminium, and titanium phosphates. Phosphorus was detected in zeolites, but phosphorus-containing compounds were not observed. Phosphorus poisoning takes place in the gas phase at high operating temperatures and with high oxygen and water contents. It was also shown that the role of phosphorus poisoning was more pronounced than the role of hydrothermal ageing alone. Phosphorus poisoning mainly affects the oxide components used in this study, not the noble metals. The results can be utilized in the development of catalytic materials and catalyst compositions that can better tolerate phosphorus poisoning under hydrothermal conditions. The results can also be applied in evaluating the effects of phosphorus on different catalyst compositions and in estimating the age of commercial catalysts.(orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Furuyama, Yuichi, E-mail: furuyama@maritime.kobe-u.ac.jp [Graduate School of Maritime Sciences, Kobe University, Fukae-Minami-Machi, Higashinada-Ku, Kobe 658-0022 (Japan); Fujita, Hirotsugu; Taniike, Akira; Kitamura, Akira [Graduate School of Maritime Sciences, Kobe University, Fukae-Minami-Machi, Higashinada-Ku, Kobe 658-0022 (Japan)

    2011-12-15

    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.

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

    International Nuclear Information System (INIS)

    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 thates, 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.

  13. Accounting for exhaust gas transport dynamics in instantaneous emission models via smooth transition regression.

    Science.gov (United States)

    Kamarianakis, Yiannis; Gao, H Oliver

    2010-02-15

    Collecting and analyzing high frequency emission measurements has become very usual during the past decade as significantly more information with respect to formation conditions can be collected than from regulated bag measurements. A challenging issue for researchers is the accurate time-alignment between tailpipe measurements and engine operating variables. An alignment procedure should take into account both the reaction time of the analyzers and the dynamics of gas transport in the exhaust and measurement systems. This paper discusses a statistical modeling framework that compensates for variable exhaust transport delay while relating tailpipe measurements with engine operating covariates. Specifically it is shown that some variants of the smooth transition regression model allow for transport delays that vary smoothly as functions of the exhaust flow rate. These functions are characterized by a pair of coefficients that can be estimated via a least-squares procedure. The proposed models can be adapted to encompass inherent nonlinearities that were implicit in previous instantaneous emissions modeling efforts. This article describes the methodology and presents an illustrative application which uses data collected from a diesel bus under real-world driving conditions. PMID:20070072

  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. An Experimental Study of Different Effects of EGR Rates on The Performance And Exhaust Emissions of The Stratified Charge Piston Direct Injection Compressed Natural Gas Engine

    Directory of Open Access Journals (Sweden)

    Saheed O. Wasiu

    2011-01-01

    Full Text Available Exhaust Gas Recirculation (EGR is one of the principal techniques used to control spark ignition NOX. A fraction of the exhaust gas is recycled through a control valve from the exhaust to the engine intake system. However, EGR has different effect on performance, combustion and emissions production that are difficult to distinguish such as increase of intake temperature, delay of Rate Of Heat Rrelease (ROHR, decrease of peak heat release, decrease in oxygen concentration etc. Therefore the impact of EGR on the aforementioned engine parameters (i.e., performance, combustion and exhaust emission is not perfectly understood, especially under high EGR rates. An experimental study has been conducted to analyze various effects of EGR rates on the performance and emissions of the stratified charge piston direct injection compressed natural gas engine and to determine the stable operating limit of the engine at different excess air ratios ( = 0.9, 1.0, 1.1 and 1.2 which represents rich, stoichiometric, slightly lean and moderately lean mixture respectively. The results showed that as the EGR is increased, the brake torque, brake specific fuel consumption decreased, while nitric oxide emissions (NO reduced drastically at various fraction of EGR, just as Unburnt Hydro Carbon (UHC increased. EGR has no significant effect on carbon monoxide (CO emission. The addition of EGR also reduces cylinder’s gas temperature and pressure. It can be concluded that in introducing EGR in DI-CNG engines, there is a tradeoff between the engine’s performance and NOX emission, while it is difficult to realize stable combustion at high temperature.

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

    OpenAIRE

    Ralf Moos

    2010-01-01

    Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more s...

  18. Qualification of diesel generator exhaust carbon steel piping to intermitted elevated temperatures

    International Nuclear Information System (INIS)

    The diesel generator exhaust piping, usually made up of carbon steel piping (e.g., ASME SA-106, SA-53), is subjected to successive short time exposures at elevated temperatures up to 1,000 F (538 C). A typical design of this piping, without consideration for creep-fatigue cumulative damage, is at least incomplete, if not inappropriate. Also, a design for creep-fatigue, usually employed for long-term exposure to elevated temperatures, would be too conservative and will impose replacement of the carbon steel piping with heat-resistant CrMo alloy piping. The existing ASME standard procedures do not explicitly provide acceptance criteria for the design qualification to withstand these intermittent exposures to elevated temperatures. The serviceability qualification proposed is based on the evaluation of equivalent full temperature cycles which are presumed/expected to be experienced by the exhaust piping during the design operating life of the diesel engine. The proposed serviceability analysis consists of: (a) determination of the permissible stress at elevated temperatures, and (b) estimation of creep-fatigue damage for the total expected cycles of elevated temperature exposures following the procedure provided in ASME Code Cases N-253-6 and N-47-28

  19. Temperature, Pressure, and Infrared Image Survey of an Axisymmetric Heated Exhaust Plume

    Science.gov (United States)

    Nelson, Edward L.; Mahan, J. Robert; Birckelbaw, Larry D.; Turk, Jeffrey A.; Wardwell, Douglas A.; Hange, Craig E.

    1996-01-01

    The focus of this research is to numerically predict an infrared image of a jet engine exhaust plume, given field variables such as temperature, pressure, and exhaust plume constituents as a function of spatial position within the plume, and to compare this predicted image directly with measured data. This work is motivated by the need to validate computational fluid dynamic (CFD) codes through infrared imaging. The technique of reducing the three-dimensional field variable domain to a two-dimensional infrared image invokes the use of an inverse Monte Carlo ray trace algorithm and an infrared band model for exhaust gases. This report describes an experiment in which the above-mentioned field variables were carefully measured. Results from this experiment, namely tables of measured temperature and pressure data, as well as measured infrared images, are given. The inverse Monte Carlo ray trace technique is described. Finally, experimentally obtained infrared images are directly compared to infrared images predicted from the measured field variables.

  20. Exhaust gas fuel reforming of Diesel fuel by non-thermal arc discharge for NOx trap regeneration application

    OpenAIRE

    Lebouvier, Alexandre; Fresnet, François; Fabry, Frédéric; Boch, Valérie; Rohani, Vandad-Julien; Cauneau, François; Fulcheri, Laurent

    2011-01-01

    The present study is dedicated to the reforming of diesel fuel with diesel engine exhaust gas (i.e., air, CO2, and H2O mixture) using a nonthermal plasma torch for a NOx trap regeneration application. The plasma technology developed is based on a high voltage/low current nonthermal plasma torch. In the first part of the paper, experimental results on synthesis gas production from exhaust gas fuel reforming of diesel fuel are reported. In the second part of the paper, these experimental result...

  1. 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 energy saving potential with great application prospect to IC engines

  2. Effect of Operating and Sampling Conditions on the Exhaust Gas Composition of Small-Scale Power Generators

    OpenAIRE

    Smits, Marianne; Vanpachtenbeke, Floris; Horemans, Benjamin; Wael, Karolien De; Hauchecorne, Birger; Van Langenhove, Herman; Demeestere, Kristof; Lenaerts, Silvia

    2012-01-01

    Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These gener...

  3. Plasma and neutral gas jet interactions in the exhaust of a magnetic confinement system

    International Nuclear Information System (INIS)

    A general purpose 2-1/2 dimensional, multifluid, time dependent computer code has been developed. This flexible tool models the dynamic behavior of plasma/neutral gas interactions in the presence of a magnetic field. The simulation has been used to examine the formation of smoke ring structure in the plasma rocket exhaust by injection of an axial jet of neutral gas. Specifically, the code was applied to the special case of attempting to couple the neutral gas momentum to the plasma in such a manner that plasma smoke rings would form, disconnecting the plasma from the magnetic field. For this scenario several cases where run scanning a wide range of neutral gas input parameters. In all the cases it was found that after an initial transient phase, the plasma eroded the neutral gas and after that followed the original magnetic field. From these findings it is concluded that smoke rings do not form with axial injection of neutral gas. Several suggestions for alternative injection schemes are presented

  4. 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

  5. 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.

  6. Temperatures and Stresses on Hollow Blades For Gas Turbines

    Science.gov (United States)

    Pollmann, Erich

    1947-01-01

    The present treatise reports on theoretical investigations and test-stand measurements which were carried out in the BMW Flugmotoren GMbH in developing the hollow blade for exhaust gas turbines. As an introduction the temperature variation and the stress on a turbine blade for a gas temperature of 900 degrees and circumferential velocities of 600 meters per second are discussed. The assumptions onthe heat transfer coefficients at the blade profile are supported by tests on an electrically heated blade model. The temperature distribution in the cross section of a blade Is thoroughly investigated and the temperature field determined for a special case. A method for calculation of the thermal stresses in turbine blades for a given temperature distribution is indicated. The effect of the heat radiation on the blade temperature also is dealt with. Test-stand experiments on turbine blades are evaluated, particularly with respect to temperature distribution in the cross section; maximum and minimum temperature in the cross section are ascertained. Finally, the application of the hollow blade for a stationary gas turbine is investigated. Starting from a setup for 550 C gas temperature the improvement of the thermal efficiency and the fuel consumption are considered as well as the increase of the useful power by use of high temperatures. The power required for blade cooling is taken into account.

  7. 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 composition of the powder was new one. Also using the laser cladding technique for ship engine parts subject of interesting.

  8. Determination of analytical dependences in order to calculate the exhaust gas boiler with helical belt inserts

    Directory of Open Access Journals (Sweden)

    Kolyadin Evgeniy Alekseevich

    2010-10-01

    Full Text Available The objective of the research is the identification of regularities of heat and aerodynamic processes and determination of analytical dependences in order to calculate heat exchange Nu = (Re, S/d and aerodynamic resistance ? = f(Re, S/d of the exhaust gas boiler with helical belt inserts. The experimental research of heat exchange and aerodynamics of all used helical belt inserts was performed in the same conditions, based on one methodology and the same ex-perimental installation. The received dependences help to evaluate the increasein heat exchange and aerodynamic resistance of a gas flow while using helical belt inserts with different geometrical specifications, and to select the best option of the geometry of the insert for a specific construction of a recuperative heat exchanger with multi-phase heat exchange environments.

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

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Paul Albert

    2010-11-01

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

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

    DEFF Research Database (Denmark)

    Xin, Gao; Andreasen, SØren Juhl

    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 exchangers with superior performance for further analysis. In this work, the on-design performances of the 4 heat exchangers are more thoroughly assessed on their corresponding optimized subsystem configurations. Afterward, their off-design performances are compared on the whole working range of the fuel 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 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-10-15

    In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH{sub (aq)}, NaOH{sub (aq)}, NaCl{sub (aq)}) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on exhaust emissions and engine performance characteristics were investigated. Experiments showed that constant HHO flow rate at low engine speeds (under the critical speed of 1750 rpm for this experimental study), turned advantages of HHO system into disadvantages for engine torque, carbon monoxide (CO), hydrocarbon (HC) emissions and specific fuel consumption (SFC). Investigations demonstrated that HHO flow rate had to be diminished in relation to engine speed below 1750 rpm due to the long opening time of intake manifolds at low speeds. This caused excessive volume occupation of hydroxy in cylinders which prevented correct air to be taken into the combustion chambers and consequently, decreased volumetric efficiency was inevitable. Decreased volumetric efficiency influenced combustion efficiency which had negative effects on engine torque and exhaust emissions. Therefore, a hydroxy electronic control unit (HECU) was designed and manufactured to decrease HHO flow rate by decreasing voltage and current automatically by programming the data logger to compensate disadvantages of HHO gas on SFC, engine torque and exhaust emissions under engine speed of 1750 rpm. The flow rate of HHO gas was measured by using various amounts of KOH, NaOH, NaCl (catalysts). These catalysts were added into the water to diminish hydrogen and oxygen bonds and NaOH was specified as the most appropriate catalyst. It was observed that if the molality of NaOH in solution exceeded 1% by mass, electrical current supplied from the battery increased dramatically due to the too much reduction of electrical resistance. HHO system addition to the engine without any modification resulted in increasing engine torque output by an average of 19.1%, reducing CO emissions by an average of 13.5%, HC emissions by an average of 5% and SFC by an average of 14%. (author)

  12. Burning of wood slabs in a conical calorimeter. Part II: emissions, oxygen consumed and exhaust temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Fernando de Souza; Castro, Andre de [Instituto Nacional de Pesquisas Espaciais (INPE), Cachoeira Paulista, SP (Brazil). Lab. Associado de Combustao e Propulsao], e-mail: fernando@lcp.inpe.br, e-mail: andre@lcp.inpe.br

    2006-07-01

    This work presents experimental data concerning the combustion characteristics of wood slabs of pinus (Pinus elliot) burned in a conical calorimeter. Emissions of CO, Co2, No and UHC, oxygen molar fractions and temperatures of exhaust gases from burning slabs (10 X 10 X 5 cm 3) were measured. The combustion behaviour during pre-heating, drying, self-ignition, pyrolysis, flaming and smoldering, for a constant cone calorimeter output of 2000 W, is compared and analysed for slabs with heated surfaces parallel and perpendicular to the wood fibers(author)

  13. Exhaust Emission Characteristics of Diesel Engine Operating on Biodiesel and its Blends at Elevated Temperature of Air

    Directory of Open Access Journals (Sweden)

    K.Sureshkumar

    2014-10-01

    Full Text Available In this study, performance and exhaust emission characteristics of Pongamia Pinnata oil blends (B10,B20,B30 and B50 with mineral diesel were investigated in preheated intake air conditions in a single cylinder 4-Stroke direct injection CI engine at 75 % maximum load and its rated engine speed 1500 rpm. Two types of heat exchanger designed to preheat the suction air and the heating is accomplished by both engine cooling water and exhaust gases. Two types of heat exchanger includes concentric tube counter flow heat exchanger (to recover heat from engine exhaust gases and shell and tube heat exchanger (to recover heat from engine jacket cooling water is mounted along intake manifold to preheat the suction air. Test is carried out at atmospheric air temperature (30oC, preheated air temperature of 45oC,60oC and75oC.Exhaust emission characteristics such as Carbon Dioxide(CO2,Carbon monoxide(CO,Unburned Hydrocarbon (HC and Nitrogen Oxide(NO. Experimental investigation revealed that except Nitrogen Oxide (NO emission and other exhaust emission parameters such as CO2,CO and HC are decreased with mineral diesel and among other biodiesel blends a drastic reduction in exhaust emission is observed for Biodiesel blend ratio B20 for all preheated air temperature .However the Nitrogen Oxide (NO emission increases with increase in biodiesel mixtures for all preheated air temperature.

  14. 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.

  15. 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)

  16. 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)

  17. Flow rate measuring method for radioactive off gas in local exhaustion facility

    International Nuclear Information System (INIS)

    In the inside of an exhaustion duct extending horizontally for flowing radioactive off-gas, a baffle plate having a size substantially covering the cross section of the duct is pivoted at the upper end thereof by means of a rotational shaft. The baffle plate is thus pivoted to the duct in a state where in can incline in the radial direction of the cross section of the duct around the rotational shaft. An indication pointer is secured to the upper end of the baffle plate penetrating a duct wall, and the pointer is tiltable together with the baffle plate around the rotational axis as a fulcrum. A display plate having gradients showing a relation between the inclination of the indication pointer and the flow rate in the duct is disposed at the back of the display pointer. When gas flows in the duct, buoyancy is caused to the baffle plate in accordance with the flow rate of the gas, whereby the baffle plate is inclined to display the flow rate corresponding to the indication pointer. (I.N.)

  18. Influence of gas temperature on temperature field in the area of transit gas-pipeline

    Science.gov (United States)

    Széplaky, Dávid; Varga, Augustín; Rajzinger, Ján

    2014-08-01

    The article describes to what extent can temperature regimes of gas-pipeline influence temperature field in the surrounding environment during transportation of natural gas in transit gas-pipeline. Basic thermo-physical properties of soil, pipe material and natural gas affect the heat transfer from the gas through the pipe wall into the surrounding soil. It is necessary to calculate the temperature course in the depth of the pipeline in time ? = 0 (no gas flow in the pipeline), to determine temperature and regime pressure of gas and soil temperature when gas pipeline is affected (gas flow in the gas-pipeline).

  19. 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

    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 on a finite-element approach. On each discretized segment, fluid properties, heat transfer process and TEG performance are locally calculated for higher model precision. To benefit both the system design and fabrication, the way to model TEG modules is herein reconsidered; a database of commercialized compact 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.

  20. Numerical Simulation of Exhaust Gas Cooling in Channels with Periodic Elbows for Application in Compact Heat Recovery Systems

    Science.gov (United States)

    Di Bari, Sergio; Cotton, James S.; Robinson, Anthony J.

    2012-11-01

    Miniature and Micro devices represent the new frontier for advanced heat and mass transfer technology. Due to the small length scales, the use of CFD is very useful for designing and optimizing microfluidic devices since experimentation and visualization at these scales can be difficult. In this work a high temperature air microfluidic cooling strategy for applications such as compact waste heat recovery, exhaust gas recirculation and fuel cell thermal management is proposed. Initially, the application of a simple straight microchannel is considered. In an effort to partially compensate for the poor thermal properties of air, right-angle bends are introduced in order to induce Dean vortices which periodically restart the thermal boundary layer development, thus improving the heat transfer and fluid mixing. Numerical simulations in the range of 100 <= ReDh <= 1000 have been carried out for channels of square cross-section. Channel wall lengths of 1.0 mm are investigated for elbow spacings of 5 mm, 10 mm and 15 mm. High temperature air (300°C) at atmospheric inlet pressure is the working fluid. The results indicate that the elbows substantially improve the local and average heat transfer in the channels while increasing the pressure drop. Design considerations are discussed which take into account the heat transfer and pressure drop characteristics of the channels.

  1. 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.

  2. Possibilities and limitations of exhaust gas analysis for expanded use in control of an AOD-converter

    OpenAIRE

    Laxén, Jonas

    2012-01-01

    The main purpose of the AOD-converter is to lower the carbon content in stainless steel production. The carbon content can be estimated by static theoretical models. It can also be estimated through dynamic models based on analysis of the exhaust gases from the converter. This master thesis is a study on an extended use of exhaust gas analysis data on the AOD-converter at Outokumpu’s stainless steel plant in Avesta, Sweden. There are two main methods of predicting the carbon content based on ...

  3. 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 the latest FTIR technology. Overall, the levels of these emissions were also mostly elevated at subnormal temperatures. Total vehicle mileage seemed not to affect cold-start emissions (CO and HC) at low temperatures. Nor did the overall durability of the emission control system appear to be worse in cold-climate conditions typical for Finland. The deterioration of the emissions performance in the tested vehicles either closely followed the average trend defined by the normal, assigned deterioration factors or was even lesser. The conclusions of this report underline the necessity of a separate low-temperature test in order to really effectively curb real-world emissions. Standards at normal temperature are no more effective alone, but need to be accompanied with additional requirements for good performance also in conditions closer to the everyday use, which comprises many cold-starts even in low ambient temperature conditions. (orig.) 75 refs.

  4. Hazardous exhaust gas monitoring using a deep UV based differential optical absorption spectroscopy (DOAS) system

    International Nuclear Information System (INIS)

    A fibre-optic sensor for the monitoring of hazardous exhaust gases is described. The sensor based on Differential Optical Absorption Spectroscopy was developed to operate within exhaust environments, monitor several exhaust gases and demonstrate low susceptibility to interferences from other gases. Experimental results describing the calibration of the sensor against a commercial analyser and tests documenting the sensor's operating capabilities within the exhaust of an engine are presented. The lower limit of detection for the sensor was found to be 5ppm for nitric oxide, and 1ppm for both nitrogen dioxide and sulphur dioxide. Response times were found to be 3.4 seconds

  5. 40 CFR 86.110-90 - Exhaust gas sampling system; diesel vehicles.

    Science.gov (United States)

    2010-07-01

    ...New Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty...CFV system (methanol-fueled Otto-cycle vehicles may be tested...temperature is not exceeded); or (iii) Using a smooth wall duct less...heat exchanger is required. (iii) The gas mixture...

  6. Selective mixed potential based ammonia exhaust gas sensor; Selektiver Ammoniakabgassensor auf Mischpotentialbasis

    Energy Technology Data Exchange (ETDEWEB)

    Schoenauer, D.; Moos, R. [Bayreuth Univ. (Germany). Lehrstuhl fuer Funktionsmaterialien; Wiesner, K.; Fleischer, M. [Siemens AG, CT PS 6, Muenchen (Germany)

    2007-07-01

    Mixed potential sensors with additional catalytic deposits on one of two electrodes show a high potential for NH{sub 3} detection. With defined reactions at the covered electrode it is possible to derive a temperature dependent correlation between the gas concentration/composition and the sensor signal which is characteristic for the used electrode material and the catalyst.

  7. Low-temperature gas from marine shales

    Directory of Open Access Journals (Sweden)

    Jarvie Daniel M

    2009-02-01

    Full Text Available 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 unprecedented. Here we report gas generation under anoxic helium flow at temperatures 300° below thermal cracking temperatures. Gas is generated discontinuously, in distinct aperiodic episodes of near equal intensity. In one three-hour episode at 50°C, six percent of the hydrocarbons (kerogen & bitumen in a Mississippian marine shale decomposed to gas (C1–C5. The same shale generated 72% less gas with helium flow containing 10 ppm O2 and the two gases were compositionally distinct. In sequential isothermal heating cycles (~1 hour, nearly five times more gas was generated at 50°C (57.4 ?g C1–C5/g rock than at 350°C by thermal cracking (12 ?g C1–C5/g rock. The position that natural gas forms only at high temperatures over geologic time is based largely on pyrolysis experiments under oxic conditions and temperatures where low-temperature gas generation could be suppressed. Our results indicate two paths to gas, a high-temperature thermal path, and a low-temperature catalytic path proceeding 300° below the thermal path. It redefines the time-temperature dimensions of gas habitats and opens the possibility of gas generation at subsurface temperatures previously thought impossible.

  8. 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

  9. COMBINED IMPACT OF BIODIESEL (MENO AND EXHAUST GAS RECIRCULATION ON NOX EMISSIONS IN DI DIESEL ENGINES

    Directory of Open Access Journals (Sweden)

    B. Jothithirumal

    2012-09-01

    Full Text Available The steep rises in the prices of the petroleum fuels and the concern for the environment have forced the researchers to find alternative renewable fuels which are called bio-fuels. The objective of this work is to find the optimum EGR and biodiesel blend matrix for the better performance and optimum emission reduction in a DI diesel engine. The bio fuel used in the experimentation is derived from the Neem oil. A twin-cylinder, air-cooled, constant speed direct injection diesel engine is used for experiments. HC, NOx, CO, and smoke of the exhaust gas are measured. Various engine performance parameters such as thermal efficiency, and brake specific fuel consumption are calculated from the acquired data. As the percentage of bio diesel increased in diesel and bio fuel blend the NOx emission increased. In order to reduce the emission from bio diesel EGR is used. Application of EGR with biodiesel blends resulted in reductions in NOx emissions without any significant penalty in smoke emissions. The results reveal that the Blend 100 (100 % bio fuel produces maximum NOx emission (300 ppm. With 25% volume flow rate of EGR with the same B100 bio diesel, the NOx emission is reduced approximately 300 ppm to 100 ppm

  10. Analysis of the state and size of silver on alumina in effective removal of NOx from oxygen rich exhaust gas.

    Czech Academy of Sciences Publication Activity Database

    Arve, K.; Klingstedt, F.; Eränen, K.; Murzin, D. Yu.; ?apek, Libor; D?de?ek, Ji?í; Sobalík, Zden?k; Wichterlová, Blanka; Svennerberg, K.; Wallenberg, L. R.; Bovin, J.-O.

    2006-01-01

    Ro?. 6, ?. 4 (2006), s. 1076-1083. ISSN 1533-4880 R&D Projects: GA AV ?R 1ET400400413 Grant ostatní: European Union(XE) GR5D-CT 2001-00595 Institutional research plan: CEZ:AV0Z40400503 Keywords : silver * exhaust gas * removal of NOx Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.194, year: 2006

  11. 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.

  12. Oxidation and corrosion fatigue aspects of cast exhaust manifolds

    OpenAIRE

    Ekström, Madeleine

    2015-01-01

    Emission regulations for heavy-duty diesel engines are becoming increasingly restrictive to limit the environmental impacts of exhaust gases and particles. Increasing the specific power output of diesel engines would improve fuel efficiency and greatly reduce emissions, but these changes could lead to increased exhaust gas temperature, increasing demands on the exhaust manifold material. This is currently the ferritic ductile cast iron alloy SiMo51, containing about 4 wt% Si and ~1 wt% Mo, wh...

  13. *GAS-PHASE AND PARTICULATE COMPONENTS OF DIESEL EXHAUST PRODUCE DIFFERENTIAL CARDIOPHYSIOLOGICAL IMPAIRMENTS IN HEALTHY RATS

    Science.gov (United States)

    We recently showed that inhalation exposure of normotensive Wistar Kyoto (WKY) rats to whole diesel exhaust (DE) elicited changes in cardiac gene expression pattern that broadly mimicked gene expression in non-exposed spontaneously hypertensive rats. We hypothesized that healthy ...

  14. 77 FR 76842 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Science.gov (United States)

    2012-12-31

    ...Test Procedures for Engine Exhaust Gaseous Emissions (Aircraft and Aircraft...whether engines meet the applicable gaseous emission standards specified in...the emissions of all regulated gaseous pollutants. Use the equipment and...

  15. 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. PMID:22062324

  16. Gas-particle partitioning of primary organic aerosol emissions: (1) Gasoline vehicle exhaust

    Science.gov (United States)

    May, Andrew A.; Presto, Albert A.; Hennigan, Christopher J.; Nguyen, Ngoc T.; Gordon, Timothy D.; Robinson, Allen L.

    2013-10-01

    The gas-particle partitioning of the primary organic aerosol (POA) emissions from fifty-one light-duty gasoline vehicles (model years 1987-2012) was investigated at the California Air Resources Board Haagen-Smit Laboratory. Each vehicle was operated over the cold-start unified cycle on a chassis dynamometer and its emissions were sampled using a constant volume sampler. Four independent yet complementary approaches were used to investigate POA gas-particle partitioning: sampling artifact correction of quartz filter data, dilution from the constant volume sampler into a portable environmental chamber, heating in a thermodenuder, and thermal desorption/gas chromatography/mass spectrometry analysis of quartz filter samples. This combination of techniques allowed gas-particle partitioning measurements to be made across a wide range of atmospherically relevant conditions - temperatures of 25-100 °C and organic aerosol concentrations of <1-600 ?g m-3. The gas-particle partitioning of the POA emissions varied continuously over this entire range of conditions and essentially none of the POA should be considered non-volatile. Furthermore, for most vehicles, the low levels of dilution used in the constant volume sampler created particle mass concentrations that were greater than a factor of 10 or higher than typical ambient levels. This resulted in large and systematic partitioning biases in the POA emission factors compared to more dilute atmospheric conditions, as the POA emission rates may be over-estimated by nearly a factor of four due to gas-particle partitioning at higher particle mass concentrations. A volatility distribution was derived to quantitatively describe the measured gas-particle partitioning data using absorptive partitioning theory. Although the POA emission factors varied by more than two orders of magnitude across the test fleet, the vehicle-to-vehicle differences in gas-particle partitioning were modest. Therefore, a single volatility distribution can be used to quantitatively describe the gas-particle partitioning of the entire test fleet. This distribution is designed to be applied to quartz filter POA emission factors in order to update emissions inventories for use in chemical transport models.

  17. 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

  18. Investigation of ambient temperature on the performance of GE-F5 gas turbine

    International Nuclear Information System (INIS)

    The role of ambient temperature in determining the performance of GE-F5 gas turbine is analysed by investigating the Shirvan gas turbine power plant 10MW, 15MW and 20MW power output. These parameters have been brought as a function of ambient temperature. The results show when ambient temperature increases 1 deg C, The compressor pressure decreases about 20kPa, compressor outlet temperature increases about 1.13 deg C and exhaust temperature increases about 2.5 deg C. It is revealed that variations are due to decreasing the efficiency of compressor and less due to mass flow rate of air reduction as ambient temperature increases at constant power output. The results shows cycle efficiency reduces 3% with increasing 50 of ambient temperature, also the m increases as ambient temperature increase for constant turbine work. These are also because of reducing the compressor efficiency as ambient temperature increases

  19. MEGAS - multi-electrode gas sensor system. Micromechanical high-temperature sensor system on a Si basis for measurements of nitrogen monoxide concentrations in motor car exhaust. Final report; MEGAS - Multi-Elektroden-Gassensorsystem. Mikromechanisches Hochtemperatur-Sensorsystem aus Silizium-Basis zur Ermittlung von Stickstoffmonoxid-Konzentrationen im Kfz-Abgas. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Junge, S.

    2002-07-01

    The IMSAS is working on an actively heated Si substrate with interdigital structures fo working temperatures up to 550 C and for aggressive working media. The following tasks were achieved: Gas sensor design; Process development and optimisation; Processing of the Si substrate; Optimisation of the sensor substrate. The following problems were encountered: Minimisation of intrinsic stress of the stratified packages; Optimisation of the adhesive strength; Development of a stable sensor heating up to 550 C; Development and optimisation of structuring methods; Combination of thin film and thick film technologies. Resistive gas sensors with titanium-tungsten mixed oxides must be heated to 500 C for fast and sensitive response to a NO atmosphere. The gas sensitivity is strongly temperature-dependent, i.e. gas sensor temperature contro is required. In the case of diesel engine catalytic converters, ambient temperatures are high and vary with the mode of operation and operating time. The sensor temperature must be at least as high as the maximum ambient temperature and must be kept stable at this level. (orig.) [German] Am IMSAS liegt der Schwerpunkt im Bereich der Entwicklung eines aktiv beheizten Siliziumsubstrates mit Interdigitalstrukturen, das Arbeitstemperaturen bis zu 550 C und aggressiven Umgebungsbedingungen standhaelt. Die Arbeitspakete lassen sich grob zusammenfassen: - Designerstellung des Gassensors - Prozessentwicklung und -optimierung - Prozessierung des Siliziumsubstrates - Optimierung des Sensorsubstrates. Aus diesen Schwerpunkten ergeben sich Schwierigkeiten, die im Projektverlauf geloest werden muessen: - Minimierung des intrinsischen Stresses der Schichtpakete - Optimierung der Haftfestigkeit der Schichten/Schichtpakete - Entwicklung einer stabilen Sensorheizung bis 550 C - Entwicklung und Optimierung der Strukturierungsmethoden - Kombination von Duenn- und Dickschichttechnik (Si-Technologie und Siebdruck). Resistive Gassensoren mit Titan-Wolfram-Mischoxiden muessen waehrend ihres Betriebs auf ca. 500 C geheizt werden, um schnell und empfindlich eine NO-Atmosphaere ansprechen zu koennen. Die Gassensitivitaet ist stark von der Temperatur abhaengig. Aus diesem Grunde muss die Temperatur des Gassensors geregelt werden. Im Anwendungsfall Dieselkatalysator sind erhoehte Umgebungstemperaturen vorhanden, diese variieren je nach Betriebsdauer und Lastfall. Die Sensortemperatur muss deshalb mindestens so hoch sein, wie die maximale Temperatur der Umgebung und dabei stabil gehalten werden. (orig.)

  20. 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

  1. 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 data provided in the literature. Further investigation of such effects on other gaseous components is recommended for future work.

  2. Palladium based catalysts for exhaust aftertreatment of natural gas powered vehicles and biofuel combustion

    International Nuclear Information System (INIS)

    Hydrothermally aged (1000/850C, 12/16h) Pd-Ce-supported alumina catalysts with high and low Ce content were prepared and tested in conversion of gas mixtures simulating the emissions from natural gas (NG) driven vehicles and biofuel combustion. The test procedure contained lean and rich light-off activity tests, stationary and oscillating lambda sweeps, space velocity tests as well as runs with sulphur poisoning. The catalysts exhibited high conversion of the model pollutants. In the oscillating lambda sweep experiments, the Pd-Ce/Al2O3 with high Ce loading showed high activities in conversion of CH4 and CO at lean ? values up to 1.04. Ageing under the reactants flow as well as hydrothermal treatment of the catalysts resulted in improved catalytic activities in terms of light-off temperatures of the model pollutants. This activation was believed to be a result of both Cl-release from the surface as well as restructuring of the Pd-particles. Interaction of Pd-Ce or Al-Ce induced at high temperature was also believed to affect the activation. Addition of 5ppm of SO2 into the gas mixture of simulated emissions from biofuel combustion raised the T50% of CH4 by approximately 100C. SO2-TPD experiments were used to correlate the catalytic activity to S-poisoning. The catalysts were characterised by H2-adsorption, XPS, FTIR, SO2-/NO-/O2-TPD, XRD, XRF and N22-TPD, XRD, XRF and N2-physisorption

  3. Increasing the Selectivity of Pt-Gate SiC Field Effect Gas Sensors by Dynamic Temperature Modulation

    OpenAIRE

    Bur, Christian; Reimann, Peter; Andersson, Mike; Schuetze, Andreas; Lloyd Spetz, Anita

    2012-01-01

    Based on a diode coupled silicon carbide field effect transistor (FET) with platinum as catalytic gate material, the influence of dynamic temperature modulation on the selectivity of gas analysis sensors FETs has been investigated. This operating mode, studied intensively for semiconductor gas sensors, has only recently been applied to FETs. A suitable temperature cycle for detection of typical exhaust gases (CO, NO, C3H6, H-2, NH3) was developed and combined with appropriate signal processin...

  4. Effect of ambient temperature on the performance of micro gas turbine with cogeneration system in cold region

    International Nuclear Information System (INIS)

    A small-scale prime mover especially micro gas turbine is a key factor in order to widespread the utilization of biogas. It is well known that a performance of large-scale gas turbine is greatly affected by its inlet air temperature. However, the effect of the inlet air temperature on the performance of small-scale gas turbine (micro gas turbine) is not widely reported. The purpose of the present study is to investigate the effect of the inlet air temperature on the performance of a micro gas turbine (MGT) with cogeneration system (CGS) arrangement. An analysis model of the MGT-CGS was set up on the basis of experimental results obtained in a previous study and a manufacturer standard data, and it was analysed under a various ambient temperature condition in a cold region. The results show that when ambient temperature increased, electrical efficiency ?ele of the MGT decreased but exhaust heat recovery ?ehr increased. It was also found that when ambient temperature increased, exhaust heat to mass flow rate Qexe/me and exhaust heat recovery to mass flow rate Qehr/me increased, with maximum ratios of 259 kJ/kg and 200 kJ/kg, respectively were found in summer peak. Furthermore, it was also found that the exhaust heat to power ratio Qexe/Pe had a similar characteristic with exhaust heat recovery to power ratio Qehr/Pe. Qexe/Pe and Qehrub>exe/Pe and Qehr/Pe increased with the increase of ambient temperature. Moreover, although different values of total energy efficiency, fuel energy saving and CO2 reduction for every temperature condition were found comparing with a two conventional system that were considered, the MGT-CGS could annually reduce 30,000-80,000 m3/y of fuel consumption and 35-94 t-CO2/y of CO2 emissions. - Research highlights: ? Micro gas turbine cogeneration system (MGT-CGS) has higher electrical efficiency and lower exhaust heat recovery efficiency under cold condition. ? MGT-CGS has lower exhaust heat and exhaust heat recovery to power ratio under cold condition. ? The performance of MGT-CGS depends on heat and electrical demands of applied facilities, and it can decide the necessity of inlet precooling. ? MGT-CGS is very efficient on total energy efficiency, fuel saving and CO2 reduction.

  5. Temperature programmable microfabricated gas chromatography column

    Science.gov (United States)

    Manginell, Ronald P.; Frye-Mason, Gregory C.

    2003-12-23

    A temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by the integration of a resistive heating element and temperature sensing on the microfabricated column. Additionally, means are provided to thermally isolate the heated column from their surroundings. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  6. Electrochemical cell with integrated hydrocarbon gas sensor for automobile exhaust gas; Elektrochemische Zelle mit integriertem Kohlenwasserstoff-Gassensor fuer das Automobilabgas

    Energy Technology Data Exchange (ETDEWEB)

    Biskupski, D.; Moos, R. [Univ. Bayreuth (Germany). Bayreuth Engine Research Center, Lehrstuhl fuer Funktionsmaterialien; Wiesner, K.; Fleischer, M. [Siemens AG, Corporate Technology, CT PS 6, Muenchen (Germany)

    2007-07-01

    In the future sensors will be necessary to control the compliance with hydrocarbon limiting values, allowing a direct detection of the hydrocarbons. Appropriate sensor-active functional materials are metal oxides, which have a hydrocarbon sensitivity but are also dependent on the oxygen partial pressure. It is proposed that the gas-sensing layer should be integrated into an electrochemical cell. The authors show that the integration of a resistive oxygen sensor into a pump cell allows a defined oxygen concentration level at the sensor layer in any exhaust gas.

  7. Influence of steam injection through exhaust heat recovery on the design performance of solid oxide fuel cell . gas turbine hybrid systems

    International Nuclear Information System (INIS)

    This study analyzed the influence of steam injection on the performance of hybrid systems combining a solid oxide fuel cell and a gas turbine. Two different configurations (pressurized system and ambient pressure system) were examined and the effects of injecting steam, generated by recovering heat from the exhaust gas, on system performances were compared. Performance variations according to the design of different turbine inlet temperatures were examined. Two representative gas turbine pressure ratios were used. Without steam injection, the pressurized system generally exhibits higher system efficiency than the ambient pressure system. The steam injection augments gas turbine power, thus increasing the power capacity of the hybrid system. The power boost effect due to the steam injection is generally greater in the relatively higher pressure ratio design in both the pressurized and ambient pressure systems. The effect of the steam injection on system efficiency varies depending on system configurations and design conditions. The pressurized system hardly takes advantage of the steam injection in terms of system efficiency. On the other hand, the steam injection contributes to the efficiency improvement of the ambient pressure system in some design conditions. In particular, a higher pressure ratio provides a better chance of efficiency increase due to the steam injection

  8. 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...

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

    OpenAIRE

    H. Smolenska

    2008-01-01

    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 micro...

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

    Science.gov (United States)

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

    1999-01-01

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

  11. 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.

  12. Medium temperature carbon dioxide gas turbine reactors

    International Nuclear Information System (INIS)

    Carbon dioxide (CO2) partial pre-cooling and partial condensation gas turbine cycles attain comparable cycle efficiencies of 46 to 48% at medium temperature of 650degC with a typical helium (He) gas turbine cycle of PBMR (45.3%) at 900degC. This higher efficiency is ascribed to: reduced compression work around the critical point of CO2 and in the liquid phase (only available in the partial condensation cycle); and consideration of variation in CO2 specific heat at constant pressure, Cp, with temperature and pressure into cycle configuration. Compared to He cycles, the CO2 cycle gas turbomachinery weight is about one-fifth while recuperator size is comparable. Considering these results, power generation cost per unit electricity is evaluated to be lower for the CO2 cycle than in the He cycle. At medium temperature of 650degC, corrosion resistance of materials and reliability of components in CO2 have been proven during extensive operation in AGRs. Lowering temperature to 650degC provides flexibility in choosing materials and eases maintenance through the lower diffusion leak rate of fission products from coated particle fuel. The proposed medium temperature CO2 gas turbine reactors are expected to be alternative solutions to current high temperature He gas turbine reactors. (author)

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

    OpenAIRE

    KÖKKÜLÜNK, Görkem; AKDO?AN, 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...

  14. Influence of heat pipe operating temperature on exhaust heat thermoelectric generation

    OpenAIRE

    Brito, F. P.; Martins, Jorge; Gonçalves, L. M.; Antunes, Nuno; Sousa, Diogo

    2013-01-01

    Increasingly stringent targets on energy efficiency and emissions, as well as growing vehicle electrification are making attractive the electric recovery of the energy normally wasted through the tailpipe of Internal Combustion Engines. Recent developments in thermoelectrics (TE) may soon make them a viable solution for such applications. This team has been exploring the potential of using TE modules in combination with variable conductance heat pipes for transferring the exhaust heat to ...

  15. 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)

  16. Detection of ethene and other hydrocarbons in gas turbine engine exhaust using non-intrusive FTIR spectroscopy

    Science.gov (United States)

    Arrigone, Giovanni M.; Welch, Michael A.; Hilton, Moira; Miller, Michael N.; Wilson, Christopher W.

    2003-04-01

    As part of the EU funded project AEROJET2, a number of gas turbine engine tests were performed in different facilities around Europe. At Farnborough, UK a Spey engine was used to test a suite of prototype optically based instrumentation designed to measure exhaust gas emissions without using extractive probe systems. In addition to the AEROJET 2 prototype instrumentation, a Bruker Equinox 55 Fourier transform infrared (FTIR) spectrometer was used to obtain infrared spectra of the exhaust plume both in emission and absorption mode. The Bruker FTIR spectrometer was fitted with a periscope system so that different lines of sight could be monitored in the plume in a vertical plane 25 cm downstream from the nozzle exit and 20 cm upstream of the center line of sight of the AEROJET 2 prototype instrumentation. DERA (now QinetiQ) provided exhaust gas analysis data for different engine running conditions using samples extracted from the plume with an intrusive probe. The probe sampled along a horizontal plane across the centerline of the engine 45 cm downstream of the nozzle exit. The Bruker spectrometer used both InSb (indium antimonide) and MCT (mercury-cadmium-telluride) detectors to maximize the sensitivity across the IR range 600-4000 cm-1. Typically, CO2 and H2O IR signatures dominate the observed spectra of the plume. However, the engine tests showed that at low power engine conditions spectral features associated with CO around 2147 cm-1 and with hydrocarbons could be observed at around 3000 cm-1. In particular the presence of ethene (C2H2) was detected from observation of its characteristic in and out of plane vibration mode at 949 cm-1. At high engine powers the presence of NO was detected at 1900.3 cm-1. Species concentrations were calculated using a slab model for each line of sight compared against reference spectra. The engine plume was assumed to be symmetric about the centerline. On this basis, data from the extractive sampling gas analysis that had been obtained by traversing the probe across a horizontal plane through the centerline could be compared with non-intrusive measurements made by scanning vertically. Adjustments have been made to account for the 20 cm downstream offset in measurement planes of the probe and the spectrometer behind the nozzle exit.

  17. Helium turbine power generation in high temperature gas reactor

    International Nuclear Information System (INIS)

    This paper presents studies on the helium turbine power generator and important components in the indirect cycle of high temperature helium cooled reactor with multi-purpose use of exhaust thermal energy from the turbine. The features of this paper are, firstly the reliable estimation of adiabatic efficiencies of turbine and compressor, secondly the introduction of heat transfer enhancement by use of the surface radiative heat flux from the thin metal plates installed in the hot helium and between the heat transfer coil rows of IHX and RHX, thirdly the use of turbine exhaust heat to produce fresh water from seawater for domestic, agricultural and marine fields, forthly a proposal of plutonium oxide fuel without a slight possibility of diversion of plutonium for nuclear weapon production and finally the investigation of GT-HTGR of large output such as 500 MWe. The study of performance of GT-HTGR reduces the result that for the reactor of 450 MWt the optimum thermal efficiency is about 43% when the turbine expansion ratio is 3.9 for the turbine efficiency of 0.92 and compressor efficiency of 0.88 and the helium temperature at the compressor inlet is 45degC. The produced amount of fresh water is about 8640 ton/day. It is made clear that about 90% of the reactor thermal output is totally used for the electric power generation in the turbine and for the multi-puposed utilization of the heat from the turbine exhaust gas and compressed helium cooling seawater. The GT-Large HTGR is realized by the separation of the pressure and temperature boundaries of the pressure vessel, the increase of burning density of the fuel by 1.4 times, the extention of the nuclear core diameter and length by 1.2 times, respectively, and the enhancement of the heat flux along the nuclear fuel compact surface by 1.5 times by providing riblets with the peak in the flow direction. (J.P.N.)

  18. 78 FR 63017 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Science.gov (United States)

    2013-10-23

    ...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate...amending the emission standards for turbine engine powered airplanes to incorporate...EPA also proposed adopting the gas turbine engine test procedures of...

  19. The High Temperature Gas-Cooled Reactor

    International Nuclear Information System (INIS)

    The key element in the deployment, performance, and safety of the High-Temperature Gas-Cooled Reactor (HTGR) is the utilization of proven high integrity microsphere fuel particles with their ceramic coatings which form a containment system which places primary emphasis on retention of fission products in the fuel. The basic particles can be embodied in a variety of different fuel element types, core sizes and geometries, and with a reactor outlet gas temperature capability up to 10000C, the gas-cooled reactor offers opportunities, unmatched by any other reactor type, for a wide spectrum of applications including electrical power generation, process heat supply, and propulsion. This paper highlights the versatility of the gas-cooled reactor for projected applications which will become paramount in the 21st century

  20. Design of thermoelectric generators operating on exhaust gas from marine diesel engines

    Directory of Open Access Journals (Sweden)

    Khalykov Kamil Rafaelevich

    2010-04-01

    Full Text Available The design of thermoelectric generator (TEG, forming the exhaust system of the vessel, is offered in the paper. Thermal calculation of the TEG for the ves-sel engine, Ro-8 6VDS48/42-AL2, with the capacity of 2 650 kW is given. Values of output parameters of the TEG are comparable with output values of the pa-rameters of existing analogues. The thermoelectric generator with the received parameters can be used on a vessel as an additional source of the direct current electric power.

  1. 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 ?g m?3 to 100 ?g 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.

  2. 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.

  3. Determining gas temperatures from laser scattering.

    Science.gov (United States)

    Salzman, J. A.; Masica, W. J.; Coney, T. A.

    1972-01-01

    Lidar techniques may be applicable to inelastic, Raman scattering. When a light beam interacts with gas molecules, the energies of scattered photons may be increased or decreased relative to the incident photons. The Raman return signal can theoretically yield information on gas pressure, temperature, and molecular species concentration. The temperature can be calculated from the measurement of two scattered Raman rotational line intensities. Questions of measurement accuracy, line selection, and multiple line ratios are considered. The measurement apparatus is discussed together with the measurement techniques.

  4. Multifunctional potentiometric gas sensor array with an integrated temperature control and temperature sensors

    Energy Technology Data Exchange (ETDEWEB)

    Blackburn, Bryan M; Wachsman, Eric D

    2015-05-12

    Embodiments of the subject invention relate to a gas sensor and method for sensing one or more gases. An embodiment incorporates an array of sensing electrodes maintained at similar or different temperatures, such that the sensitivity and species selectivity of the device can be fine tuned between different pairs of sensing electrodes. A specific embodiment pertains to a gas sensor array for monitoring combustion exhausts and/or chemical reaction byproducts. An embodiment of the subject device related to this invention operates at high temperatures and can withstand harsh chemical environments. Embodiments of the device are made on a single substrate. The devices can also be made on individual substrates and monitored individually as if they were part of an array on a single substrate. The device can incorporate sensing electrodes in the same environment, which allows the electrodes to be coplanar and, thus, keep manufacturing costs low. Embodiments of the device can provide improvements to sensitivity, selectivity, and signal interference via surface temperature control.

  5. Simultaneous high-speed gas property measurements at the exhaust gas recirculation cooler exit and at the turbocharger inlet of a multicylinder diesel engine using diode-laser-absorption spectroscopy.

    Science.gov (United States)

    Jatana, Gurneesh S; Magee, Mark; Fain, David; Naik, Sameer V; Shaver, Gregory M; Lucht, Robert P

    2015-02-10

    A diode-laser-absorption-spectroscopy-based sensor system was used to perform high-speed (100 Hz to 5 kHz) measurements of gas properties (temperature, pressure, and H2O vapor concentration) at the turbocharger inlet and at the exhaust gas recirculation (EGR) cooler exit of a diesel engine. An earlier version of this system was previously used for high-speed measurements of gas temperature and H2O vapor concentration in the intake manifold of the diesel engine. A 1387.2 N?m tunable distributed feedback diode laser was used to scan across multiple H2O absorption transitions, and the direct absorption signal was recorded using a high-speed data acquisition system. Compact optical connectors were designed to conduct simultaneous measurements in the intake manifold, the EGR cooler exit, and the turbocharger inlet of the engine. For measurements at the turbocharger inlet, these custom optical connectors survived gas temperatures as high as 800 K using a simple and passive arrangement in which the temperature-sensitive components were protected from high temperatures using ceramic insulators. This arrangement reduced system cost and complexity by eliminating the need for any active water or oil cooling. Diode-laser measurements performed during steady-state engine operation were within 5% of the thermocouple and pressure sensor measurements, and within 10% of the H2O concentration values derived from the CO2 gas analyzer measurements. Measurements were also performed in the engine during transient events. In one such transient event, where a step change in fueling was introduced, the diode-laser sensor was able to capture the 30 ms change in the gas properties; the thermocouple, on the other hand, required 7.4 s to accurately reflect the change in gas conditions, while the gas analyzer required nearly 600 ms. To the best of our knowledge, this is the first implementation of such a simple and passive arrangement of high-temperature optical connectors as well as the first documented application of diode-laser absorption for high-speed gas dynamics measurements in the turbocharger inlet and EGR cooler exit of a diesel engine. PMID:25968043

  6. Test facilities for HTR, (1). Elevated temperature high pressure large helium gas loop

    Energy Technology Data Exchange (ETDEWEB)

    Nakase, Tsuyoshi; Miyata, Toyohiko; Tanabe, Yutaka; Yasufuku, Katsumi; Katoh, Masayuki

    1981-12-01

    The multi-purpose high temperature gas-cooled experimental reactor is operated at 1000 deg C and 40 kg/cm/sup 2/ g, and the design with high reliability and safety is required for the system and equipment composing it. For the development of them, the design must be performed with proved data. The high temperature, high pressure large helium gas loop was installed in Kawasaki Heavy Industries Ltd. to carry out the various tests for developing this reactor in technological scale and to obtain the proved data. In May, 1981, this loop was operated at 1000 deg C and 40 kg/cm/sup 2/ g with helium flow rate of 720 kg/h. At present, the test on the heat insulation structure for high temperature piping is performed. The planned tests include those on the reliability and safety of system and high temperature equipment, the elements of high temperature equipment, helium gas purification and high temperature measurement. The helium gas loop comprises main circulation system, refining system, helium supply and exhaust system, testing section, measuring and control system, and electric equipment. Another high temperature, high pressure helium gas loop is constructed in Fuji Electric Research Institute, and the completion is scheduled in June, 1982. The planned tests and the helium gas loop are outlined.

  7. 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 goals. Several flex-fuel demonstration vehicles were designed and built for carrying out calibration development and final testing to quantify the technology merits. Based on the extensive test results collected from dynamometer and vehicle testing, the fuel economy benefits of cooled EGR from the intended level of turbocharger technology were quantified. When combined with turbo downsizing, the FE benefits are considered large enough for E0 fuel as well as for E85 fuel to warrant further development of the technology beyond the current proof-of-concept level to a level that can meet production driveability quality and durability requirements in order to meet customers’ expectations. Cold-start cart test results from the emissions segment of the project were positive, confirming the assumption of faster thermal response of turbo exhaust system for emissions reductions for both E0 and E85 fuels. Vehicle emissions test results directionally correlated to the cold-start cart findings. The limited number of test runs did demonstrate the potentials of meeting stringent emission standards, however, they did not comprehend the factors such as hardware variability and long-term durability, 3 which are essential for mass production to satisfy customers’ expectations. It is therefore recommended, moving forward, durability concerns over turbocharger, EGR system and aftertreatment system, which would likely impact production viability, should be addressed. The data moreover suggested that further FE increase is likely with turbocharger technology advancement.

  8. The Performance Test on Local Exhaust Ventilation (LEV System to Prevent Chlorine Gas Leakage in Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    Nor Halim Hasan

    2013-08-01

    Full Text Available Water is a necessity of life to humans and animals. In Malaysia, Government Link Companies (GLC or Private Companies manages most of the water treatment plants. Chlorine gas is used as one of the water treatment media to treat raw water that will then be distributed for public or commercial usage. The large volume of Chlorine gases used and stored in these treatment plants has the potential to create a disaster if it leaks. Objective of this paper to highlight a result of Local Exhaust Ventilation (LEV monitoring system and their performance test in controlling of air flow from the chlorine gas building to prevent leakage and spread to the surrounding environment. Methodology used follows the American Governmental Industrial Hygienist (ACGIH. The Chlorine Gas leakage system is checked and verified by using ACGIH Standard. Finally as a result, all the measured parameters (velocity, flow rate, face velocity and brake horse power (bhp show that the measurement and monitoring system of LEV are complied with ACGIH Standard and Local Law and Regulations.

  9. 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.

  10. Equilibrium molecular dynamics and mean first passage time analysis of the separation of exhaust gases at high temperatures by silica nanoporous membranes

    International Nuclear Information System (INIS)

    An investigation of mechanisms associated with the high selectivity of a gas mixture at high temperatures by silica nanoporous membranes has been conducted in the framework of equilibrium classical molecular dynamic simulations and formalism of fractional diffusion equation on a sample of a gas mixture of exhaust gases. The important feature is the quite realistic modeling of the silica nanoporous membranes based on the use of an analytic bond order potential and the conception of dangling bonds. The last two were successfully employed to model the realistic silica chemical vapor deposition process (Burlakov et al 2001 Phys. Rev. Lett. 86 3052). The dependence of the selective properties on temperature, density (voidage volume) and morphology has been investigated. The selectivity at a low temperature (673?K) is found to be more efficient than at a high temperature (873?K). When only Lennard-Jones interaction between a gas and a solid is included the selectivity is found to be changed at the low temperature (673?K) from 1.2?:?1 for a density of 50% to 1.03?:?1 for a density of 80%. Including an additional electrostatic interaction increases the selectivity from 1.79?:?1 for a density of 50% to 2.26?:?1 for a density of 80%. At the high temperature (873?K) when only Lennard-Jones potential is included the selectivity is found to be changed from 1.21?:?1 for a density of 50% to 1.13?:?1 for a density of 80%. With an additional electrostatic force the selectivity is found to be the same for all densities at around 1.43?:?1. The conclusion is that the most efficient conditions for the selective membrane are a temperature of 673?K and a high density. Under these conditions the mean first passage times for species O2 and N2 are almost the same and much less than for species CO2. The methodology developed is general. This paper is based on the author's PhD thesis

  11. 40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.

    Science.gov (United States)

    2010-07-01

    ...performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine...require a sample conditioning column containing CaSO4 or desiccating...Methane Measurement Using Gas Chromatography.” (Incorporated by...

  12. 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

  13. 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.

  14. Modelling diesel engines with a variable-geometry turbocharger and exhaust gas recirculation by optimization of model parameters for capturing non-linear system dynamics

    OpenAIRE

    Wahlstro?m, Johan; Eriksson, Lars

    2011-01-01

    A mean-value model of a diesel engine with a variable-geometry turbocharger (VGT) and exhaust gas recirculation (EGR) is developed, parameterized, and validated. The intended model applications are system analysis, simulation, and development of model-based control systems. The goal is to construct a model that describes the gas flow dynamics including the dynamics in the manifold pressures, turbocharger, EGR, and actuators with few states in order to obtain short simulation times. An investi...

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

    Science.gov (United States)

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

    2012-06-01

    Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced mutagenic effects most effectively in the gas phase. Mutagenicity of particle extracts was less efficiently diminished. No significant differences of mutagenic effects were observed among the tested fuels. In conclusion, the benefits of the DOC concern regulated emissions except NO(X) as well as nonregulated emissions such as the mutagenicity of the exhaust. The reduction of mutagenicity was particularly observed in the condensates of the gas phase. This is probably due to better accessibility of gaseous mutagenic compounds during the passage of the DOC in contrast to the particle-bound mutagens. Concerning the particulate emissions DOC especially decreased ultrafine particles. PMID:22587467

  16. IAEA high temperature gas cooled reactor activities

    International Nuclear Information System (INIS)

    IAEA activities on high temperature gas cooled reactors are conducted with the review and support of Member States, primarily through the International Working Group on Gas Cooled Reactors (IWGGCR). This paper summarises the results of the IAEA gas cooled reactor project activities in recent years along with ongoing current activities through a review of Co-ordinated Research Projects (CRPs), meetings and other international efforts. A series of three recently completed CRPs have addressed the key areas of reactor physics for LEU fuel, retention of fission products, and removal of post shutdown decay heat through passive heat transport mechanisms. These activities along with other completed and ongoing supporting CRPs and meetings are summarised with reference to detailed documentation of the results. (author)

  17. Analysis of separation characteristics of low temperature distillation system in fuel supply and exhaust system for nuclear fusion reactors

    International Nuclear Information System (INIS)

    The most promising method for the hydrogen isotope separation in the fuel supply and exhaust system for nuclear fusion reactors is low temperature distillation method. In order to establish the design and operation methods for low temperature distillation towers, it is necessary to perform the experimental research and theoretical analysis for long period. The author has studied on the analysis model of low temperature distillation towers. The problem of low temperature distillation is that the experimental data of high accuracy are difficult to obtain because of many restrictions on the measurement. Accordingly, the analysis depends on the estimation by computer aid. In hydrogen isotopic separation, it is important to estimate accurately the amount of components existing in very small amount in output flow. The latent heat of evaporation is different according to the components. The decay of tritium generates heat. Hydrogen isotope system deviates from the law of Raoult. The effect of the three factors on the steady characteristics of a tower was examined, and the deviation from the law of Raoult affected most. (Kako, I.)

  18. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 11: COMPRESSOR DRIVER EXHAUST

    Science.gov (United States)

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  19. 40 CFR 86.1310-90 - Exhaust gas sampling and analytical system; diesel engines.

    Science.gov (United States)

    2010-07-01

    ... Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty...under this option); or (iii) Omitting the duct and performing...see Figure N90-6). (iii) For the CFV-CVS or EFC-CFV-CVS...good engineering practice. (iii) The overflow gas flow...

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

    Directory of Open Access Journals (Sweden)

    Jarvie Daniel M

    2009-11-01

    Full Text Available 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 gas flow and substantial in closed reactions. In sequential closed reactions at 100°C, gas from a Cretaceous Mowry shale progresses from predominately heavy hydrocarbons (66% C5, 2% C1 to predominantly light hydrocarbons (56% C1, 8% C5, the opposite of that expected from desorption of preexisting hydrocarbons. Differences in catalyst substrate composition explain these dynamics. Gas flow should carry heavier hydrocarbons to catalytic sites, in contrast to static conditions where catalytic sites are limited to in-place hydrocarbons. In-place hydrocarbons and their products should become lighter with conversion thus generating lighter hydrocarbon over time, consistent with our experimental results. We recognize the similarities between low-temperature gas generation reported here and the natural progression of wet gas to dry gas over geologic time. There is now substantial evidence for natural catalytic activity in source rocks. Natural gas at thermodynamic equilibrium and the results reported here add to that evidence. Natural catalysis provides a plausible and unique explanation for the origin and evolution of gas in sedimentary basins.

  1. Exhaust gas sensors for NO{sub x} storage catalysts and ammonia SCR systems; Abgassensoren fuer NO{sub x}-Speicherkatalysatoren und Ammoniak-SCR-Systeme

    Energy Technology Data Exchange (ETDEWEB)

    Moos, R. [Bayreuth Univ. (DE). Bayreuth Engine Research Center (BERC)

    2008-07-01

    Measuring of the air-to-fuel ratio and/or the exhaust gas oxygen content with the help of an exhaust gas sensor has been established thirty years ago. Whereas the original thimble type lambda probe, which is still shown today in textbooks, is a product of classical ceramic technology, newer sensors are manufactured in planar multilayer technology stemming from electronic technology. This is the basis for additional functionalities like NO{sub x} or ammonia sensitivities. Due to increasing requirements for OBD, the sensor of the future might be a multifunctional device which allows for measuring application specific components as well as lambda in a wide range. From a technical standpoint, it would even today be feasible to manufacture an integrated exhaust gas sensor that can measure ammonia, NO{sub x}, and lambda at the same time. Whether the direct catalyst status diagnosis will become ripe for serial application does not depends only on technical questions and cost considerations but also on the issue whether one is willing to establish a completely novel way of catalyst detection in the exhaust pipe. (orig.)

  2. Development of a catalytic water gas shift reactor for fusion fuel exhaust streams

    International Nuclear Information System (INIS)

    Catalytic reactors based on the water gas shift reaction were designed, built and tested to provide data for the design of a prototype reactor as an alternative to the uranium hot metal beds in a Fusion Fuel Clean Up (FCU) system. The reactor was designed so it could be implemented into a FCU using only existing technology. A closed loop system was chosen so that safety and net efficiency would not be compromised during upset conditions. The system uses only pure reactants thus eliminating the requirement for a carrier gas. The prototype reactor contains only 10 g of catalyst and is expected to last at least five years. The reactor is small and operates at about490 K. It will convert water to hydrogen, at a CO/H2O ratio of 1.5 with greater than 98% efficiency and with an estimated 95% efficiency for a tritiated stream of 90,000 Ci/day

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

    Science.gov (United States)

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

    2006-01-01

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

  4. 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

  5. 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.

  6. Effects of gasoline property on exhaust emission; Gasoline sosei ga haishutsu gas ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kameoka, A.; Tsuruga, F.; Hosoi, K. [Japan Automobile Research Institute Inc., Tsukuba (Japan)

    1998-10-15

    In order to clarify the impact factors of gasoline property on emission gas, continuous measurement and behavior analysis of emission gas were carried out during running of vehicles. Two passenger vehicles of 2L (A) and 2.5L (B) in total displacement, catalyst aged for hours equivalent to 10,000km running and dummy catalyst with no catalytic effects were used for the experiment. A learning control system was also adopted only for the vehicle A. In 11 mode running, CO, THC and NOx emissions increased with aromatic content in gasoline in No.1 trip. In 10/15 mode running, although CO and THC emissions increased with aromatic content in gasoline, the amount of NOx emission was dependent on the kind of vehicles. On the vehicle B with no learning control system, it was probably derived from the fact that an air excess rate increases with an increase in fuel mass by supplying high-density high-aromatic gasoline. CO, THC and NOx increased with sulfur content in gasoline. In particular, the sulfur content had a large effect on NOx emission. 2 refs., 13 figs., 2 tabs.

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

    Science.gov (United States)

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

    2015-06-01

    Mechanic workers are exposed to exhaust fumes when controlling vehicle engines in motion inside repair shops. To assess radiation doses due to radon short-lived progeny from the inhalation of exhaust fumes by mechanic workers, concentrations of these radionuclides were measured in petrol (gasoline) and gas-oil exhaust fumes by evaluating mean critical angles of etching of the CR-39 and LR-115 type II SSNTDs for alpha particles emitted by the radon and thoron decay series. Committed effective doses due to Po and Po short-lived radon decay products from the inhalation of petrol and gas-oil exhaust fumes by workers were evaluated. A maximum value of 1.35 mSv y due to radon short-lived decay products from the inhalation of gas-oil exhaust fumes by mechanic workers was found, which is lower than the (3-10 mSv y) dose limit interval for workers. PMID:25905520

  8. The Analysis of Exhaust Gas Thermal Energy Recovery Through a TEG Generator in City Traffic Conditions Reproduced on a Dynamic Engine Test Bed

    Science.gov (United States)

    Merkisz, Jerzy; Fuc, Pawel; Lijewski, Piotr; Ziolkowski, Andrzej; Wojciechowski, Krzysztof T.

    2015-06-01

    We present an analysis of thermal energy recovery through a proprietary thermoelectric generator (TEG) in an actual vehicle driving cycle reproduced on a dynamic engine test bed. The tests were performed on a 1.3-L 66-kW diesel engine. The TEG was fitted in the vehicle exhaust system. In order to assess the thermal energy losses in the exhaust system, advanced portable emission measurement system research tools were used, such as Semtech DS by Sensors. Aside from the exhaust emissions, the said analyzer measures the exhaust mass flow and exhaust temperature, vehicle driving parameters and reads and records the engine parameters. The difficulty related to the energy recovery measurements under actual traffic conditions, particularly when passenger vehicles and TEGs are used, spurred the authors to develop a proprietary method of transposing the actual driving cycle as a function V = f( t) onto the engine test bed, opn which the driving profile, previously recorded in the city traffic, was reproduced. The length of the cycle was 12.6 km. Along with the motion parameters, the authors reproduced the parameters of the vehicle and its transmission. The adopted methodology enabled high repeatability of the research trials while still ensuring engine dynamic states occurring in the city traffic.

  9. Purex canyon exhaust fan bearing temperature monitoring system doric 245 datalogger programming

    International Nuclear Information System (INIS)

    A micro-processor based datalogger is used to monitor, display, and log seventeen RTD temperature channels. Five bearings are monitored for each of the three electric motor-fan assemblies and two bearings are monitored on the steam turbine unit. Several alarms per data channel (a High alarm at 236 degrees and a High High alarm at 246 degrees F) will alert the operation's staff to increasing abnormal bearing temperatures. This procedure is cross-referenced to the manufacturers manual. All programming steps will have the following footnote: Mpg x-xx. The Mpg refers to the Manual page, with x as the section number and xx as the page number in that section. When more information is needed, such as pictures or details, then the manual section and page number is provided

  10. 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 indicative of high reproducibility. A silver-paste-based brazing technique was used to assemble the TE elements into modules. This assembly technique afforded low and repeatable electrical contact resistance (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.

  11. 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.)

  12. 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 (clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models. PMID:24970083

  13. A car air-conditioning system based on an absorption refrigeration cycle using energy from exhaust gas of an internal combustion engine

    Scientific Electronic Library Online (English)

    G, Vicatos; J, Gryzagoridis; S, Wang.

    Full Text Available Energy from the exhaust gas of an internal combustion engine is used to power an absorption refrigeration system to air-condition an ordinary passenger car. The theoretical design is verified by a unit that is tested under both laboratory and road-test conditions. For the latter, the unit is install [...] ed in a Nissan 1400 truck and the results indicate a successful prototype and encouraging prospects for future development.

  14. Development of high temperature metallic melting processes related to detritiation of exhausted control rods

    International Nuclear Information System (INIS)

    A rather critical problem to be faced in developing a safe strategy for the management of tritiated solid wastes is dealing with the outgassing property of tritium. Releases of tritium under elemental or oxide form may occur from waste items at different temperatures and rates depending upon the nature of tritium bonds into the waste matrix as well as on its 'contamination history'. Apart from the commercial value of tritium, its release from waste packages anyhow represents a risk of tritium exposure that cannot be accepted by skippers, by store and disposal site operators as well as by the general public. Consequently it is mandatory to carry out the detritiation of such wastes before their packaging and storage or disposal. In the boron carbide control rods from the Lingen BWR after about three years of operation, tritium generated by neutron reaction was essentially retained in the B4C matrix. The objectives of the study are to demonstrate the feasibility of two processes aimed at reducing to the maximum practicable extent the level of tritium contamination in such waste management are facilitated

  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 200?m 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. High temperature coatings for gas turbines

    Science.gov (United States)

    Zheng, Xiaoci Maggie

    2003-10-21

    Coating for high temperature gas turbine components that include a MCrAlX phase, and an aluminum-rich phase, significantly increase oxidation and cracking resistance of the components, thereby increasing their useful life and reducing operating costs. The aluminum-rich phase includes aluminum at a higher concentration than aluminum concentration in the MCrAlX alloy, and an aluminum diffusion-retarding composition, which may include cobalt, nickel, yttrium, zirconium, niobium, molybdenum, rhodium, cadmium, indium, cerium, iron, chromium, tantalum, silicon, boron, carbon, titanium, tungsten, rhenium, platinum, and combinations thereof, and particularly nickel and/or rhenium. The aluminum-rich phase may be derived from a particulate aluminum composite that has a core comprising aluminum and a shell comprising the aluminum diffusion-retarding composition.

  17. Exhaust Emission Characteristics of Diesel Engine Operating on Biodiesel and its Blends at Elevated Temperature of Air

    OpenAIRE

    Sureshkumar, K.; *, K.Muralidharan

    2014-01-01

    In this study, performance and exhaust emission characteristics of Pongamia Pinnata oil blends (B10,B20,B30 and B50) with mineral diesel were investigated in preheated intake air conditions in a single cylinder 4-Stroke direct injection CI engine at 75 % maximum load and its rated engine speed 1500 rpm. Two types of heat exchanger designed to preheat the suction air and the heating is accomplished by both engine cooling water and exhaust gases. Two types of heat exchanger incl...

  18. Controlling exhaust gas recirculation

    Science.gov (United States)

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

    2012-01-31

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

  19. 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.

  20. On the influence of solid rocket propellant exhaust gas on the stratospheric chemistry: Investigations using a three-dimensional photochemical circulation model

    International Nuclear Information System (INIS)

    The work investigated in how far large orbital rockets (e.g., space shuttle, Titan IV or, in the future, Ariane V), which emit their exhaust gas directly into the atmosphere, are cumbersome to the global atmosphere and especially the stratosphere. In particular, it investigated in how far existing chemical steady-states are influenced entailing damage to the ozone layer. With the aid of a photochemical 3-D model which comprises the most important ozone-relevant reactions and calculates the distribution of 20 trace gases for any time-step, precise statements regarding the global effect could be made. Besides the horizontal distribution of the exhaust gases, particular attention was paid to their vertical distribution and to the impact on O3 concentration and individual groups of trace substances. (orig./KW)

  1. The effect of ambient temperature and humidity on the carbon monoxide emissions of an idling gas turbine

    Science.gov (United States)

    Kauffman, C. W.; Subramaniam, A. K.

    1977-01-01

    Changes in ambient temperature and humidity affect the exhaust emissions of a gas turbine engine. The results of a test program employing a JT8D combustor are presented which quantize the effect of these changes on carbon monoxide emissions at simulated idle operating conditions. Analytical results generated by a kinetic model of the combustion process and reflecting changing ambient conditions are given. It is shown that for a complete range of possible ambient variations, significant changes do occur in the amount of carbon monoxide emitted by a gas turbine engine.

  2. 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.

  3. Corrosion of Exhaust and Filtration Equipment in a Radioactive Waste Incinerator

    International Nuclear Information System (INIS)

    Condensation in the exhaust gas system of an incinerator burning low activity radioactive wastes led to numerous corrosion developments and rapid failure of the discharge filters. The problem was traced to insufficient reheat of the exhaust gases following scrubbing. Rust particulate and moisture loaded the filters, leading to water accumulation, chloride cracking of the filter housings, and plugging and tearing of the filter media itself. To mitigate the problem, the exhaust gas temperature was increased, thermal insulation was installed on the ductwork, and the interiors of the ducts and new filter housings were lined with a protective coating

  4. 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 on EFBC using robust measurement methods and b the efficacy of scrubbers for the removal of particulate matter by size and composition.

  5. 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 quality on EFBC using robust measurement methods and (b the efficacy of scrubbers for the removal of particulate matter by size and composition.

  6. High-temperature Gas Reactor (HTGR)

    Science.gov (United States)

    Abedi, Sajad

    2011-05-01

    General Atomics (GA) has over 35 years experience in prismatic block High-temperature Gas Reactor (HTGR) technology design. During this period, the design has recently involved into a modular have been performed to demonstrate its versatility. This versatility is directly related to refractory TRISO coated - particle fuel that can contain any type of fuel. This paper summarized GA's fuel cycle studies individually and compares each based upon its cycle sustainability, proliferation-resistance capabilities, and other performance data against pressurized water reactor (PWR) fuel cycle data. Fuel cycle studies LEU-NV;commercial HEU-Th;commercial LEU-Th;weapons-grade plutonium consumption; and burning of LWR waste including plutonium and minor actinides in the MHR. results show that all commercial MHR options, with the exception of HEU-TH, are more sustainable than a PWR fuel cycle. With LEU-NV being the most sustainable commercial options. In addition, all commercial MHR options out perform the PWR with regards to its proliferation-resistance, with thorium fuel cycle having the best proliferation-resistance characteristics.

  7. 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 main flow. Pressure recovery in the annular diffuser is even high er than for design point because vortices energize the boundary layer and the turbulence level in the core flow is very high. Turbulent energy is better transported to the peripheral zones of the channel by the swirled flow. A small positive swirl angle in the inlet flow (behind the rotating bladed wheel in experiments) has a stabilizing effect on the diffuser, while negative swirl decreases its performance. This occurs due to change in the development of vertical structures downstream of the rotor blade tip area. The tip leakage flow from the last turbine stage positively affects pressure recovery in the diffuser energizing the boundary layer. Comparison of results for different diffuser test rig configurations with results from a more gas turbine-like test rig with a similar diffuser and a scaled turbine stage model and for higher Mach numbers showed similar pressure recovery trends, verifying the results.

  8. On Developing a Spectroscopic System for Fast Gas Temperature Measurements in Combustion Environments

    DEFF Research Database (Denmark)

    Evseev, Vadim; Clausen, SØnnik

    2009-01-01

    Fourier Transform Infra Red (FTIR) spectroscopy techniques are known to provide reliable results for gas temperature measurements and can be comparatively easily performed on an industrial scale such as a boiler on a power plant or an exhaust of a ship engine cylinder. However temporal resolution is not high enough to trace fast temperature variations which are of great importance for complete combustion diagnostics. To eliminate the above mentioned shortcoming, a new IR spectroscopic-imaging system has been developed at Risø DTU. The schematic of the system is presented. Results on lab and industrial scale are discussed. System’s flexibility and changeability which enable applying of a number of other methods for combustion diagnostics are demonstrated.

  9. Hadron resonance gas and nonperturbative QCD vacuum at finite temperature

    OpenAIRE

    Agasian, Nikita O.; Fedorov, Sergei M.

    2003-01-01

    We study the nonperturbative QCD vacuum with two light quarks at finite temperature in the framework of hadron resonance gas. Temperature dependence of the quark and gluon condensates in the confined phase are obtained. We demonstrate that the quark condensate and one half (chromo-electric component) of gluon condensate evaporate at the same temperature, which corresponds to the temperature of quark-hadron phase transition. Critical temperature is T_c~190 MeV when temperatur...

  10. Effect of cooling the recirculated exhaust gases on diesel engine emissions

    International Nuclear Information System (INIS)

    Although combustion is essential in most energy generation processes, it is one of the major causes of air pollution. Spiral fin exhaust pipes were designed to study the effect of cooling the recirculated exhaust gases (EGR) of Diesel engines on the chemical composition of the exhaust gases and the reduction in the percentages of pollutant emissions. The gases examined in this study were oxides of nitrogen (NOx), carbon dioxide (CO2) and carbon monoxide (CO). In addition, O2 concentration in the exhaust was measured. The two designs adopted in this study were exhaust pipes with solid and hollow fins around them. The first type uses air flow around the fins to cool the exhaust gases. The second type consists of hollow fins around the exhaust pipe to allow cooling water to flow in the hollow passage. Different combinations and arrangements of the solid and hollow fins exhaust pipes were used. It was found that decreasing the temperature of the EGR resulted in reductions in the oxides of nitrogen (NOx) and carbon dioxide (CO2) but increased the carbon monoxide (CO) in the exhaust gases. In addition, the oxygen (O2) concentration in the exhaust was decreased. As a general trend, the percentages of reduction in the NOx gas concentrations were lower than the percentages of increase in the CO emissions as a result of cooling the EGR of a Diesel engine by a heat exchanger. Using water as a cooling meeat exchanger. Using water as a cooling medium decreased the exhaust gases temperature and the amount of pollutants more than did air as a cooling medium. In a separate series of tests, increasing the cooled EGR ratios decreased the exhaust NOx but increased the particulate matter concentrations in the exhaust gases

  11. Experimental study of heat transfer coefficient in exhaust pipe

    Energy Technology Data Exchange (ETDEWEB)

    Bourouga, B.; Bouloc, F. [Nantes Univ., Nantes (France). LTN/UMR; Anthoine, P. [Renault, Rueil Malmaison (France). Direction de la Mecanique

    2010-07-01

    Exhaust gas from spark-ignition engines are one of the main sources of atmospheric pollution, especially in urban areas where traffic is dense. In order to comply with increasingly restrictive standards, the automobile industry must develop cleaning devices such as catalytic converters and particle filters. This experimental study examined the influence of a flow's intermittent character on the heat transfer coefficient within a bent exhaust pipe. A device was developed to estimate the heat transfer coefficient on the right channel or the bent portion of the exhaust line in a periodic intermittent flowing regime, as well as in a steady regime. The goal was to build a database of coefficient and augmentation factors (CAF) for the simulation of heat transfer in a variety of basic geometries found in spark-ignition engine exhaust lines. Parietal heat flux and wall temperature were estimated from temperature measurements using the Beck inverse algorithm. Estimates of gas temperature were derived by Tagawa's method, using temperature measurements in the intermittent gas flow with a two thermocouples probe. The results showed that intermittency intensifies heat transfer in the straight pipe as well as in the bent pipe. The augmentation factor within the straight pipe depends on the frequency. Peak intensification depends on the mechanical frequency of resonance on the tube. The augmentation factor for the bent pipe was found to be lower than in the straight pipe, and did not depend on the frequency. 22 refs., 7 figs.

  12. Studi Experimental Penggunaan Venturi Scrubber dan Cyclonic Separator Untuk Meningkatkan Kinerja pada Sistem Exhaust Gas Recirculation (EGR dalam Menurunkan NOX pada Motor Diesel

    Directory of Open Access Journals (Sweden)

    Samsu Dlukha N

    2012-09-01

    Full Text Available Salah satu cara yang efektif untuk mengurangi NOX adalah dengan menggunakan metode Exhaust Gas Recirculation (EGR. Dengan metode EGR, oksigen yang masuk ke ruang bakar akan berkurang sehingga NOX dapat diturunkan dengan signifikan, akan tetapi power dari mesin tersebut juga akan berkurang dan Particulate Matter (PM akan naik secara signifikan. Dalam penelitian ini dibahas penggunaan EGR yang telah di optimalkan dengan penambahan venturi scrubber dan cyclonic separator, tujuannya mengurangi NOX tanpa meningkatkan PM. Hasil pengujian menunjukkan NOX turun sebesar 48.89% dan PM turun dari 69,87%  menjadi 9.87%.

  13. 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 agreement with thermocouple readings. Gas lines and bands from CO, CO2 and H2O can be observed in the spectra. CO was only observed at the first measuring port (100ms) with the strongest CO-signal seen during experiments with straw particles. Variations in gas concentration (CO2 and H2O) and the signal from solid particles reflects variations in particle feeding rates during the experiments.

  14. Effect of isothermal dilution on emission factors of organic carbon and n-alkanes in the particle and gas phases of diesel exhaust

    Science.gov (United States)

    Fujitani, Yuji; Saitoh, Katsumi; Fushimi, Akihiro; Takahashi, Katsuyuki; Hasegawa, Shuich; Tanabe, Kiyoshi; Kobayashi, Shinji; Furuyama, Akiko; Hirano, Seishiro; Takami, Akinori

    2012-11-01

    To investigate the effect of isothermal dilution (30 °C) on emission factors (EFs) of semivolatile and nonvolatile compounds of heavy-duty diesel exhaust, we measured EFs for particulate matter (PM), organic carbon (OC), and elemental carbon (EC) in the particle phase, and EFs for n-alkanes in both the particle phase and the gas phase of exhaust produced under high-idle engine operating conditions at dilution ratios (DRs) ranging from 8 to 1027. The EC EFs did not vary with DR, whereas the OC EFs in the particle phase determined at DR = 1027 were 13% of the EFs determined at DR = 8, owing to evaporation of organic compounds. Using partitioning theory and n-alkane EFs measured at DR = 14 and 238, we calculated the distributions of compounds between the particle and gas phases at DR = 1760, which corresponds to the DR for tailpipe emissions as they move from the tailpipe to the roadside atmosphere. The gas-phase EF of a compound with a vapor pressure of 10-7 Pa was 0.01 ?g kg-1-fuel at DR = 14, and this value is 1/330 the value derived at DR = 1760. Our results suggest that the EFs of high-volatility compounds in the particle phase will be overestimated and that the EFs of low-volatility compounds in the gas phase will be underestimated if the estimates are derived from data obtained at the low DRs and they are applied to the real world. Therefore, extrapolation from EFs derived at low DR values to EFs at atmospherically relevant DRs will be a source of error in predictions of the concentrations of particulate matter and gas-phase precursors to secondary organic aerosols in air quality models.

  15. Effect of Exhaust Gas Recirculation on the Dual Fuel Combustion of Gasoline and CNG by Compression Ignition

    OpenAIRE

    Aziz, A. Rashid A.; Raja Shahzad; Noraz Al-Khairi; Naveenchandran, P.

    2011-01-01

    Homogeneous Charge Compression Ignition (HCCI) is a combustion process that promises the combination of diesel like efficiencies and very low NOx emissions. The major issues with HCCI are high heat release rates, lack of combustion control and high CO and HC emissions. Operating HCCI with two fuels of different properties and recirculation of exhaust gases are effective strategies of promoting and controlling autoignition. This study discusses the effects of EGR on the combustion characterist...

  16. Mixer conditions temperature of liquified gas streams

    Science.gov (United States)

    Talmor, E.

    1966-01-01

    Room temperature gaseous hydrogen mixed with liquified hydrogen in a venturi produces a two- phased liquid hydrogen stream at a stable temperature. This technique is useful in laboratory testing where presently, temperature control is maintained by a calibrated heat leak that results in considerable expenditure of cryogenic refrigerants.

  17. Biomass Gasification and High Temperature Gas Cleaning.

    Czech Academy of Sciences Publication Activity Database

    Hejdová, Petra; Solich, M.; Vosecký, Martin; Malecha, J.; Koutský, B.; Pun?ochá?, Miroslav; Skoblia, Sergej

    - : -, 2005, s. 221-224. ISBN 80-8073-382-1. [New Trends in Technology Systems Operation'05. Prešov (SK), 20.11.2005-21.11.2005] R&D Projects: GA ?R(CZ) GA104/04/0829 Institutional research plan: CEZ:AV0Z40720504 Keywords : biomass and waste * gas ification * hot gas cleaning Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  18. Effects of inlet distortion on gas turbine combustion chamber exit temperature profiles

    Science.gov (United States)

    Maqsood, Omar Shahzada

    Damage to a nozzle guide vane or blade, caused by non-uniform temperature distributions at the combustion chamber exit, is deleterious to turbine performance and can lead to expensive and time consuming overhaul and repair. A test rig was designed and constructed for the Allison 250-C20B combustion chamber to investigate the effects of inlet air distortion on the combustion chamber's exit temperature fields. The rig made use of the engine's diffuser tubes, combustion case, combustion liner, and first stage nozzle guide vane shield. Rig operating conditions simulated engine cruise conditions, matching the quasi-non-dimensional Mach number, equivalence ratio and Sauter mean diameter. The combustion chamber was tested with an even distribution of inlet air and a 4% difference in airflow at either side. An even distribution of inlet air to the combustion chamber did not create a uniform temperature profile and varying the inlet distribution of air exacerbated the profile's non-uniformity. The design of the combustion liner promoted the formation of an oval-shaped toroidal vortex inside the chamber, creating localized hot and cool sections separated by 90° that appeared in the exhaust. Uneven inlet air distributions skewed the oval vortex, increasing the temperature of the hot section nearest the side with the most mass flow rate and decreasing the temperature of the hot section on the opposite side. Keywords: Allison 250, Combustion, Dual-Entry, Exit Temperature Profile, Gas Turbine, Pattern Factor, Reverse Flow.

  19. Temperature distribution measurement in the hot gas duct of HENDEL

    International Nuclear Information System (INIS)

    The HENDEL (Helium Engineering Demonstration Loop) which was completed on March, 1982, has been operated 3 times so far, including a test operation when it was handed over to JAERI. In the main part of HENDEL which is called a Mother + Adapter (M+A) loop, a hot gas duct through which helium gas of 10000C, 40 atm, 4kg/s flows is installed. This report deals with the measurement and evaluation of temperature distribution of the hot gas duct. The maximum surface temperature of the hot gas duct was 2300C, which is low enough, compared with an allowable design temperature of 3500C. The effective thermal conductivity of the insulation inside the hot gas duct was found to be 0.40 - 0.49 kcal/mh0C. (author)

  20. 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.

  1. Effect of Exhaust Gas Recirculation on the Dual Fuel Combustion of Gasoline and CNG by Compression Ignition

    Directory of Open Access Journals (Sweden)

    A. Rashid A. Aziz

    2011-01-01

    Full Text Available Homogeneous Charge Compression Ignition (HCCI is a combustion process that promises the combination of diesel like efficiencies and very low NOx emissions. The major issues with HCCI are high heat release rates, lack of combustion control and high CO and HC emissions. Operating HCCI with two fuels of different properties and recirculation of exhaust gases are effective strategies of promoting and controlling autoignition. This study discusses the effects of EGR on the combustion characteristics of dual fuel HCCI of gasoline and CNG. The results show that EGR retards ignition timing, affects thermal efficiency and reduces heat release rates.

  2. Nitrogen charge temperature prediction in a gas lift valve

    Directory of Open Access Journals (Sweden)

    Marcelo M. Ganzarolli

    2010-03-01

    Full Text Available The operation of a class of retrievable gas-lift valves (GLV is controlled by the axial movement of a bellows. One force acting on the bellows is due to the pressure exerted by the nitrogen gas contained in the GLV dome. It depends on the nitrogen temperature, which is influenced by both the production fluid and the injection gas temperatures in the well. This work investigated this dependence for a GLV installed in a side pocket mandrel tube. Three independent procedures were used for this purpose, comprising a compact thermal model, an experimental investigation with a thermal mockup and a numerical analysis. From these, a correlation for the nitrogen temperature was proposed, based on the local production fluid and injection gas temperatures, and on their convective coefficients with the mandrel tube surfaces.

  3. Nitrogen charge temperature prediction in a gas lift valve

    Scientific Electronic Library Online (English)

    Marcelo M., Ganzarolli; Carlos A. C., Altemani.

    2010-03-01

    Full Text Available The operation of a class of retrievable gas-lift valves (GLV) is controlled by the axial movement of a bellows. One force acting on the bellows is due to the pressure exerted by the nitrogen gas contained in the GLV dome. It depends on the nitrogen temperature, which is influenced by both the produc [...] tion fluid and the injection gas temperatures in the well. This work investigated this dependence for a GLV installed in a side pocket mandrel tube. Three independent procedures were used for this purpose, comprising a compact thermal model, an experimental investigation with a thermal mockup and a numerical analysis. From these, a correlation for the nitrogen temperature was proposed, based on the local production fluid and injection gas temperatures, and on their convective coefficients with the mandrel tube surfaces.

  4. Heat pipe temperature control utilizing a soluble gas absorption reservior

    Science.gov (United States)

    Saaski, E. W.

    1976-01-01

    A new gas-controlled heat pipe design is described which uses a liquid matrix reservior, or sponge, to replace the standard gas reservior. Reservior volume may be reduced by a factor of five to ten for certain gas-liquid combinations, while retaining the same level of temperature control. Experiments with ammonia, butane, and carbon dioxide control gases with methanol working fluid are discussed.

  5. 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)

  6. High frequency gas temperature and surface heat flux measurements

    OpenAIRE

    Iliopoulou, Vasiliki

    2005-01-01

    Further improvements of the thermal efficiency of gas turbine cycle are closely coupled to the increase of turbine inlet temperature. This requires intensive and efficient cooling of the blades. In this perspective, experimental investigations of the gas temperature and heat transfer distribution around the airfoil are of primary importance. The present work aims at the development of two measurement techniques based on applications of the thin film sensors: the two-layer gauge for the wall h...

  7. Glow curve analysis for constant temperature hot gas TLD readers

    Energy Technology Data Exchange (ETDEWEB)

    Dijk, J.W.E. van; Julius, H.W. (Gezondheidsorganisatie TNO, Arnhem (Netherlands). Radiologische Dienst)

    1993-01-01

    In constant temperature hot gas TLD systems, the heating profile of the TL chip is an exponential function of time. A method is presented which enables glow curve deconvolution for non-linear heating systems. The reproducibility of the heating process of constant temperature hot gas systems can be such that a fast linear optimisation procedure can be used for automatic 'at sight glow curve interpretation' suitable for overall reader performance quality control. (author).

  8. Method of purifying exhaust gases

    International Nuclear Information System (INIS)

    Purpose: To effectively purify exhaust gases containing high density NOx and/or sulfite gases by maintaining high denitrating and desulfating rates even at a high temperature above 1200C. Method: Fine powder composed of hydrous silica, bentonite or acidic white clay having adsorption water at the surface thereof is added to exhaust gases containing NOx and/or sulfite gases, and ionizing radiation rays are irradiated to the exhaust gases under the presence of the powder to clean the exhaust gases. The amount of water adsorbed to the powder is adjusted to 2.5 - 10% by weight of the dried powder at 1000C. By adding the powder to the exhaust gases and irradiating the ionizing radiation rays, the denitrating and desulfating effects can be improved, the required dose of the or ionizing radiation rays can be reduced and the mists resulted under the irradiation of the ionizing radiation rays can completely be collected. (Yoshihara, H.)

  9. Gas Generation Testing of Neptunium Oxide at Elevated Temperature

    International Nuclear Information System (INIS)

    Elevated temperature gas generation tests have been conducted using neptunium dioxide produced on a laboratory scale using the HB-Line Phase II flowsheet. These tests were performed to determine what effect elevated temperatures would have on the neptunium dioxide in comparison to neptunium dioxide tested at ambient temperature. The headspace gas compositions following storage at elevated temperatures associated with normal conditions of transport (NCT) have been measured. These test results show an increase in hydrogen generation rate at elevated temperature and significant removal of oxygen from the headspace gas. The elevated temperature gas generation tests described in this report involved heating small test vessels containing neptunium dioxide and measuring the headspace gas pressure and composition at the end of the test period. Four samples were used in these tests to evaluate the impact of process variables on the gas generation rate. Two samples were calcined to 600 degrees Celsius and two were calcined to 650 degrees Celsius. Each test vessel contained approximately 9.5 g of neptunium dioxide. Following exposure to 75 per cent relative humidity (RH) for five days, these samples were loaded in air and then heated to between 105 and 115 degrees Celsius for about one month. At the conclusion of the test period, the headspace gas of each container was analyzed using a micro-gas chromatograph installed in the glovebox where the experiments were conducted. The prere the experiments were conducted. The pressure, volume, and composition data for the headspace gas samples were used to calculate average H2 generation rates

  10. Development history of the gas turbine modular high temperature reactor

    International Nuclear Information System (INIS)

    The development of the high temperature gas cooled reactor (HTGR) as an environmentally agreeable and efficient power source to support the generation of electricity and achieve a broad range of high temperature industrial applications has been an evolutionary process spanning over four decades. This process has included ongoing major development in both the HTGR as a nuclear energy source and associated power conversion systems from the steam cycle to the gas turbine. This paper follows the development process progressively through individual plant designs from early research of the 1950s to the present focus on the gas turbine modular HTGR. (author)

  11. A laser-based sensor for measurement of off-gas composition and temperature in basic oxygen steelmaking

    International Nuclear Information System (INIS)

    We are developing an optical sensor for process control in basic oxygen steelmaking. The sensor measures gas temperature and relative CO/CO2 concentration ratios in the furnace off-gas by transmitting the laser probe beam directly above the furnace lip and below the exhaust hood during oxygen blowing. Dynamic off-gas information is being evaluated for optimizing variables such as lance height, oxygen flow, post-combustion control, and prediction of final melt-carbon content. The non-invasive nature of the optical sensor renders it robust and relatively maintenance-free. Additional potential applications of the method are process control for electric arc furnace and bottom-blown oxygen steelmaking processes. (author)

  12. Partially integrated exhaust manifold

    Energy Technology Data Exchange (ETDEWEB)

    Hayman, Alan W; Baker, Rodney E

    2015-01-20

    A partially integrated manifold assembly is disclosed which improves performance, reduces cost and provides efficient packaging of engine components. The partially integrated manifold assembly includes a first leg extending from a first port and terminating at a mounting flange for an exhaust gas control valve. Multiple additional legs (depending on the total number of cylinders) are integrally formed with the cylinder head assembly and extend from the ports of the associated cylinder and terminate at an exit port flange. These additional legs are longer than the first leg such that the exit port flange is spaced apart from the mounting flange. This configuration provides increased packaging space adjacent the first leg for any valving that may be required to control the direction and destination of exhaust flow in recirculation to an EGR valve or downstream to a catalytic converter.

  13. 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

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

    Science.gov (United States)

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

    2015-05-11

    A new and simple method for benzene, toluene, ethylbenzene and o-xylene (BTEX) quantification in vehicle exhaust was developed based on diffusion-controlled extraction onto a retracted solid-phase microextraction (SPME) fiber coating. The rationale was to develop a method based on existing and proven SPME technology that is feasible for field adaptation in developing countries. Passive sampling with SPME fiber retracted into the needle extracted nearly two orders of magnitude less mass (n) compared with exposed fiber (outside of needle) and sampling was in a time weighted-averaging (TWA) mode. Both the sampling time (t) and fiber retraction depth (Z) were adjusted to quantify a wider range of Cgas. Extraction and quantification is conducted in a non-equilibrium mode. Effects of Cgas, t, Z and T were tested. In addition, contribution of n extracted by metallic surfaces of needle assembly without SPME coating was studied. Effects of sample storage time on n loss was studied. Retracted TWA-SPME extractions followed the theoretical model. Extracted n of BTEX was proportional to Cgas, t, Dg, T and inversely proportional to Z. Method detection limits were 1.8, 2.7, 2.1 and 5.2mgm(-3) (0.51, 0.83, 0.66 and 1.62ppm) for BTEX, respectively. The contribution of extraction onto metallic surfaces was reproducible and influenced by Cgas and t and less so by T and by the Z. The new method was applied to measure BTEX in the exhaust gas of a Ford Crown Victoria 1995 and compared with a whole gas and direct injection method. PMID:25911428

  15. 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...

  16. Exhaust Manifold Design – FEA Approach

    Directory of Open Access Journals (Sweden)

    Gopaal

    2014-11-01

    Full Text Available The Exhaust manifold in the engines is an important component which has a considerable effect on the performance of the I.C engine. The exhaust manifold operates under high temperature and pressure conditions. Their design usually has to be performed by trial and error through many experiments and analyses. Therefore, an automated design optimization would reduce technical, schedule, and cost risks for new engine developments. This paper deals with the various factors that are to be considered in the design of the exhaust manifold. It tries to explain the effect of various factors during the Finite Element Analysis.

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

    Science.gov (United States)

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

    2012-05-15

    Nowadays, the drastic pollution problems, some of them related with greenhouse gas emissions, have promoted important attempts to face and diminish the global warming effects on the Mexico Valley Metropolitan Zone (MVMZ) as well as on the huge urban zones around the world. To reduce the exhaust gas emissions, many efforts have been carried out to reformulate fuels and design new catalytic converters; however, it is well known that other variables such as socio-economic and transport structure factors also play an important role around this problem. The present study analyzes the roles played by several commonly-used three-way catalytic converters (TWC) and the average traffic speed in the emission of N(2)O as greenhouse gas. According to this study, by increasing the average traffic flow and avoiding constant decelerations (frequent stops) during common trips, remarkable environmental and economic benefits could be obtained due to the diminution of N(2)O and other contaminant emissions such as ammonia (NH(3)) and even CO(2) with the concomitant reduced fossil fuel consumption. The actions mentioned above could be highly viable to diminish, in general, the global warming effects and contamination problems. PMID:22245865

  18. 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.

  19. 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 by injection of NH3 with carrier gas into the flue gas. NH3 can react with NO and form N2, but a competing reaction path is the oxidation of NH3 to NO.The SNR process is briefly described and it is shown by chemical kinetic modelling that OH radicals under the present conditions will initiate the reaction of NH3 by formation of NH2 and NH radicals.Mixing in reacting gas phase systems is described by an empirical mixing model (the droplet diffusion model). The mixing process is separated into macro- and micromixing. The macromixing is assumed to be ideal while the micromixing is modelled by molecular diffusion. The SNR process is simulated using the mixing model and an empirical kinetic model based on laboratory experiments.A bench scale reactor set-up has been built using a natural gas burner to provide the main reaction gas. The set-up has been used to perform an experimental investigation 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 to the injected gas as well.The effects of the NH3 flow and natural gas addition were as expected from earlier studies in laboratory reactors and pilot plants.The experiments indicates that the SNR process was only dependenton the O2 concentration in the flue gas without any effect due to variation of the O2 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. The difference in the NO outlet concentration for varied carrier gas flow seems to have a maximum at 1350 K and is then decreasing for higher temperatures. This is in good agreement with an analysis of the micromixing effects.The mixing effect observed in the experiments can be described by the momentum ratio between the injected jet and the flue gas in crossflow both for the 1.0 mm and 1.9 mm nozzle, indicating that for momentum ratios above 30 there is no further improvement of the mixing. For decreasing momentum ratios below 30 the NO outlet concentration is increasing for temperatures above 1200 K. For temperatures below 1200 K the NO outlet concentration is unaffected because of lower reaction rates.The droplet diffusion model is used to model the experimental results and it can describe the influence of the carrier gas flow with a successful result.

  20. 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 vor, diese Messverfahren beruhen aber auf dem Absorptionsprinzip in Fluessigkeiten, das umstaendlich zu handhaben ist und eine grosse Querempfindlichkeit zu anderen Stoffen besitzt. Fuer die Emissionsmessung von Aminen gibt es derzeit noch keine VDI-Richtlinie. Aufgrund der Komplexitaet des Mediums Abgas ist eine selektive Anreicherung bestimmter Substanzklassen wuenschenswert. So koennen Stoerungen bei der Probenahme verringert werden, indem nur die Gasphase, und hier moeglichst nur eine Substanzklasse, selektiv angereichert wird. Dazu eignet sich besonders die Luftprobenahme auf dem Prinzip der Diffusionsabscheidung. Diese Diffusionsabscheider (Denuder) sind ein bekanntes Messsystem zur nachweisstarken und selektiven Anreicherung von Spurenschadstoffen in der Aussenluft. In diesem Vorhaben soll nun dieses Konzept der Diffusionsabscheidung auf die Anwendbarkeit im Emissionsbereich ueberprueft werden, speziell zur Erfassung der leichtfluechtigen aliphatischen Aldehyde und Amine (primaere und sekundaere) mit extrem niedrigen Nachweisgrenzen (<10 ppb). (orig./SR)

  1. 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...

  2. Titanium dioxide thin films for high temperature gas sensors

    International Nuclear Information System (INIS)

    Titanium dioxide (TiO2) thin film gas sensors were fabricated via the sol-gel method from a starting solution of titanium isopropoxide dissolved in methoxyethanol. Spin coating was used to deposit the sol on electroded aluminum oxide (Al2O3) substrates forming a film 1 ?m thick. The influence of crystallization temperature and operating temperature on crystalline phase, grain size, electronic conduction activation energy, and gas sensing response toward carbon monoxide (CO) and methane (CH4) was studied. Pure anatase phase was found with crystallization temperatures up to 800 oC, however, rutile began to form by 900 oC. Grain size increased with increasing calcination temperature. Activation energy was dependent on crystallite size and phase. Sensing response toward CO and CH4 was dependent on both calcination and operating temperatures. Films crystallized at 650 oC and operated at 450 oC showed the best selectivity toward CO.

  3. Coolant purification system of high-temperature gas cooled reactors

    International Nuclear Information System (INIS)

    Systems for purifying the coolant of high-temperature gas-cooled reactors are discussed. In the Dragon reactor helium is purified from radioactive isotopes of inert gases by adsorbing them on activated carbon at -1960C. Krypton and xenon are retained in a system consisting of five identical adsorbers. The use of four adsorbers (the fifth is in reserve) ensures retention of xenon for 200 hr and of krypton for 15 hr. The Peach Bottom reactor also has cryogenic purification system with helium blown through the fuel elements. The gas temperature at the activated carbon outlet is 210C and the operating temperature is 16 to 420C. The full heat load of the adsorbers is 1.7 kW; the calculated temperature is 1960C. A purification system for a high-temperature thorium reactor with 300 MW (el) power is also described. The basic parameters used in designing a coolant purification system are given. In the Fulton reactor, with 1160 MW (el), there is an additional regeneration system for radioactive gas. The total operating time of the system is several months per year. Analysis of the purification system loops of the high-temperature gas-cooled reactors shows that fission product escape is prevented by three barriers, which ensure protection of personnel and the environment from the hazard of radioactive gases. These are the fuel particle coatings, the first loop, and the shielding within which the facility is located. The advantages of te facility is located. The advantages of the cryogenic system of purification - high efficiency, small dimensions, and reliability in operation - have been demonstrated in operation on producing high-temperature gas reactors. The data obtained are widely used in designing similar systems for higher power high-temperature reactors. (H.E.)

  4. 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 $\\hbox{T}\\sim 10^{7}\\hbox{K}$.

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

    International Nuclear Information System (INIS)

    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/mf ? 10-6 and T/mf ? 10-3. (orig.)

  6. 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.)

  7. Extracting the shear viscosity of a high temperature hadron gas

    CERN Document Server

    Romatschke, Paul

    2014-01-01

    Quark-Gluon plasmas produced in relativistic heavy-ion collisions quickly expand and cool, entering a phase consisting of multiple interacting hadronic resonances just below the QCD deconfinement temperature. The transport properties of this hot hadron gas are poorly understood, yet they play an important role in our ability to infer transport properties of the quark-gluon plasma, because experimental measurements integrate over the whole system evolution. Assuming that the hot hadron gas can be modeled by a hadron cascade code based on kinetic theory assuming binary interactions, the shear viscosity over entropy ratio of a hot hadron gas for temperatures in between 120 MeV and 170 MeV is extracted. Furthermore, we present estimates for a second order transport coefficient, the shear viscous relaxation time at a temperature of 165 MeV.

  8. Gas Hydrate Stability at Low Temperatures and High Pressures

    Science.gov (United States)

    Marion, G. M.; Kargel, J. S.; Catling, D. C.

    2003-12-01

    Several papers have recently suggested that decomposition of gas hydrates could have played an important role in the geologic history of Mars and Europa. Gas hydrates form in porous sediments under low temperatures and high pressures. The FREZCHEM model was developed to predict chemical equilibria over the temperature range from -70 to 25° C and the pressure range from 1 to 1000 bars using the Pitzer equations, which are valid to high ionic strengths. The objectives of this paper were to (1) add gas (carbon dioxide and methane) hydrate chemistry to the FREZCHEM model, and (2) use the model to examine hypothetical gas hydrate chemistries on Mars and Europa. For the gas hydrate model, key variables and constants that were quantified as functions of pressure and temperature were solubility products, gas solubilities, and activity coefficients. Based on this work, new state-of-the-art stability diagrams were developed for carbon dioxide and methane hydrates in pure water and seawater. Applications to Mars a

  9. Finite Temperature Momentum Distribution of a Trapped Fermi Gas

    OpenAIRE

    Chen, Qijin; Regal, C. A.; Jin, D. S.; Levin, K

    2006-01-01

    We present measurements of the temperature-dependent momentum distribution of a trapped Fermi gas consisting of $^{40}$K in the BCS-BEC crossover regime. Accompanying theoretical results based upon a simple mean-field ground state are compared to the experimental data. Non-monotonic effects associated with temperature, $T$, arise from the competition between thermal broadening and a narrowing of the distribution induced by the decrease in the excitation gap $\\Delta(T)$ with ...

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

    DEFF Research Database (Denmark)

    Fernandes, Frederico Augusto Pires; Christiansen, Thomas Lundin

    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.

  11. Shear Viscosity of a Superfluid Dipolar Gas at Low Temperatures

    Directory of Open Access Journals (Sweden)

    M. Khademi Dehkordi

    2014-02-01

    Full Text Available We compute the shear viscosity of superfluid Bose and Fermi gases on the base of Boltzmann equation and relaxation times. We show that, in the low temperature limit, the shear viscosities of Bose and Fermi gases are proportional to T-1evp0/T and T-4, respectively. For the superfluid Bose gas at low temperature limit, only splitting processes contribute to the shear viscosity.

  12. Storage heater for high temperature gas generation; Koon gas hasseiyo chikunetsutai kanetsuki

    Energy Technology Data Exchange (ETDEWEB)

    Natani, S.; Fujiwara, Y.; Yamamura, T.; Ban, H.; Kurosaka, T. [Kobe Steel, Ltd., Kobe (Japan); Wakasugi, K. [Shinagawa Refractories Co. Ltd., Tokyo (Japan)

    1996-05-01

    This paper describes a cored brick storage heater for high temperature gas generation. This heater can generate high temperature gas by storing the thermal energy of combustion gas in a storage heater and passing draft gas through the storage heater to conduct the heat. City gas is used as the combustion gas and high pressure air is used as the draft gas. The storage heater is composed of a storage heater, burner for heat storage, reheat bypass cooler, hot valve, high pressure air source, and pressurized air pipes. The gas flow directions of the both are the reverse. Although the pebble heater using metal or ceramic balls has been adopted for the storage heater, a cored brick heater, in which ceramic heat storage bricks with numerous through holes are accumulated, has become to be used. The latter has the advantage of low pressure loss, low heat loss, and prevention of floating of heat storage bricks. A two-dimensional heat transfer simulation has been developed for the optimum operation. It can calculate the heat transfer and the heat exchange. The zirconia cored brick with high temperature resistance has been developed. It was confirmed through the trial operation that the practical heater provides the designed performance. 5 refs., 7 figs., 3 tabs.

  13. 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...

  14. Engine Cylinder Temperature Control

    Science.gov (United States)

    Kilkenny, Jonathan Patrick (Peoria, IL); Duffy, Kevin Patrick (Metamora, IL)

    2005-09-27

    A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

  15. Pengaruh Variasi Temperatur Sintesa, Temperatur Operasi dan Konsentrasi gas CO terhadap sensitivitas Sensor Gas Co dari Material ZnO

    Directory of Open Access Journals (Sweden)

    Endah Lutfiana

    2014-03-01

    Full Text Available Karbon monoksida ( CO merupakan gas yang tidak berwarna dan tidak berbau yang dihasilkan dari proses pembakaran yang tidak sempurna. Gas ini sangat beracun bagi tubuh manusia karena sifat biologinya yang mampu berikatan dengan hemoglobin yang mana bertugas membawa oksigen dalam darah, sehingga kadar oksigen dapat menurun drastis dan menyebabkan keracunan bahkan kematian. Sehingga dibutuhkan suatu alat pendeteksi atau sensor untuk mendeteksi adanya gas tersebut.Oksida metal seringkali digunakan untuk material sensor. ZnO merupakan suatu material semikonduktor yang telah digunakan untuk aplikasi sensor. Dalam penelitian ini pembuatan sensor ZnO dilakukan dengan mengoksidasi serbuk Zn pada variasi temperatur 800, 850, 900 oC selama 40 menit. Selanjutnya dibuat pelet sensor dengan mengkompaksi serbuk ZnO hasil Oksidasi dengan tekanan 200 Bar. Pelet kemudian disinter dengan temperatur 500oC. Setelah itu dilakukan pengujian SEM, XRD, dan uji Sensitivitas dengan variasi temperatur operasi 30, 50, 100 oC dan variasi konsentrasi 10 ppm, 50 ppm, 100 ppm, 250 ppm, 500 ppm. Dari hasil pengujian didapatkan nilai sensitivitas tertinggi pada temperatur sintesa 800oC dengan konsentrasi gas CO 500 ppm pada temperatur operasi sensor 100oC yaitu sebesar 0,52.

  16. Positron lifetime experiments in low temperature 3He gas

    International Nuclear Information System (INIS)

    Positron lifetime spectra were measured in 3He for temperatures 3-16 K and densities 120-432 amagat. Free positron and positron-3He clusters, as well as positronium induced cavities in the gas, are observed. Data are compared with previous work in 4He. (Auth.)

  17. Determination of the hot intracluster gas temperature from submillimeter measurements

    CERN Document Server

    Pointecouteau, E; Barret, D

    1997-01-01

    Measurements of the Sunyaev-Zeldovich (hereafter SZ) distorsion of the cosmic microwave background can give interesting physical informations on clusters of galaxies, provided that the electronic temperature of the gas is known. Previous attempts to do so have used the electronic temperature determination obtained from the X-ray spectra. However, if the intergalactic gas is not homogeneous, the X-ray emission will trace the denser component, and the temperature determination may not be relevant for the lower density gas which is dominating the SZ measurements. Moreover, the X-ray brightness decreases very rapidly with the distance, which is not the case for the SZ effect. Distant clusters might be detected from SZ measurements, whereas they are inaccessible to X-ray observations. For these reasons, we have investigated the possibility to derive the electronic temperature of the gas from the SZ measurements in the submillimeter range (lambda ~ 300-600 micro-m). We show that given the sensitivities of the futur...

  18. Critical temperature for the nuclear liquid-gas phase transition

    International Nuclear Information System (INIS)

    The charge distribution of the intermediate mass fragments produced in p (8.1 GeV)+Au collisions is analyzed in the framework of the statistical multifragmentation model with the critical temperature for the nuclear liquid-gas phase transition Tc as a free parameter. It is found that Tc=20±3 MeV (90% C.L.)

  19. Gas counter for low temperature Conversion Electron Mössbauer Spectroscopy experiments

    International Nuclear Information System (INIS)

    The operation of a gas counter, designed for Conversion Electron Mössbauer Spectroscopy measurement at low temperature, has been investigated. The experimental setup is described and tested with two pure gases, He and Ne, and two mixtures, He-5%CH4 and He-5%N2. The impacts on the counter performances of the applied voltage, the gas composition and pressure as well as the gas renewing are investigated between 41 K and 300 K. This investigation is made using 119Sn Mössbauer source and metallic tin absorber. The appropriate operating conditions of the present counter have been established for temperatures down to 41 K for both pure gases, and 61 and 85 K for He-5%N2 and He-5%CH4 respectively.

  20. 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.

  1. Magnetic resonance studies of atomic hydrogen gas at low temperatures

    International Nuclear Information System (INIS)

    Using a pulsed low temperature discharge in a closed cell containing H2 and 4He, we have been able to store a low density (approximately 1012 atoms/cc) gas of atomic hydrogen for periods of order one hour in zero magnetic field and T=1 K. Pulsed magnetic resonance at the 1420 MHz hyperfine transition has been used to study a number of the properties of the gas, including the recombination rate H + H + 4He?H2 + 4He, the hydrogen spin-exchange relaxation rates, the diffusion coefficient of H in 4He gas and the pressure shift of the hyperfine frequency due to the 4He buffer gas. Here we discuss the application of hyperfine frequency shifts as a probe of the H-He potential, and as a means for determining the binding energy of H on liquid helium

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

    Directory of Open Access Journals (Sweden)

    Ili? 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. Simulation of fission gas release during temperature transients

    International Nuclear Information System (INIS)

    Paper discusses the release of fission gases Xe and Kr as a diffusion process. It takes into account gas generation due to fission, gas precipitation in bubbles within the grains, diffusion of gas towards the grain boundaries, formation of grain boundary bubbles, its saturation and subsequent gas release, resolution of the gas contained into both types of bubbles and grain growth. Temperature profile calculations have allowed to evaluate the gas distribution in fuel pellet and in each grain. Analytical and numerical methods are used. Several experiments are simulated with the code and a good agreement between the measured Paper discusses the release of fission gases Xe and Kr as a diffusion process. It takes into and calculated results has been obtained. The influence of the initial grain size and density on fission gas release has been evaluated. It has been found that larger grain size and lower density both yield lower release, but density variation has a minor effect on the release. (author). 10 refs, 4 figs

  4. A CFD solver with variable gas properties for applications to high temperature gas-cooled reactors

    International Nuclear Information System (INIS)

    High temperature gas-cooled reactors are characterized by very high operational temperature, graphite moderator, and high pressure and high velocity gas coolant flow in the core. Computational Fluid Dynamics (CFD) methods are used to simulate the thermal and flow behavior of these systems. Typically, CFD codes rely on constant property descriptions of the fluids. For application to high temperature gas-cooled reactors, in particular to hydrogen-cooled space reactors, the constant property assumption could introduce unacceptable error Nuclear systems often see density, temperature and pressure variations that require the use of variable property modeling. A time-dependent CFD solver is developed to account for temperature and pressure variations of helium and other coolant properties (density, heat capacity, thermal conductivity, and viscosity) throughout the reactor system. The primary model uses the Reynolds- Average Navier-Stokes approach to solve for the full set of Navier-Stokes equations in turbulent flows. An implicit-explicit time-dependent MacCormack method with modified Causon limiter is implemented. The k-? model is used to account for the effect of turbulence. The CFD solver is validated using a series of benchmark problems and it is applied to the analysis of a high temperatures gas-cooled reactor coolant channel. (authors)

  5. Spectroscopic support of laser remote sensing of the sulfur dioxide gas in the jet of engine exhaust gases

    Science.gov (United States)

    Voitsekhovskaya, O. K.; Kashirskii, D. E.; Egorov, O. V.

    2013-09-01

    The feasibility of SO2 registration in the plume of a jet engine as one of the methods of monitoring of its operation quality is investigated. Spectral characteristics are calculated using the line by line method, information-computing complex TRAVA developed by the authors, and the compiled spectroscopic database on high-temperature SO2. Unlike the HITRAN database, the original spectroscopic data possess predictability up to T = 1500 K. It is established that in case of active SO2 detection using a CO laser, the laser line corresponding to the 32-31 ?5 transition is promising for temperatures T = 300-1100 K. In addition, the most suitable range of the spectrum for passive sensing of hot SO2 in the engine plume - 1330.0-1331.6 cm-1 - is established in which the useful signal level exceeds background radiation for a minimum SO2 concentration (5 ppm).

  6. 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.

  7. MAGNETIC RESONANCE STUDIES OF ATOMIC HYDROGEN GAS AT LOW TEMPERATURES

    OpenAIRE

    Hardy, W.; Morrow, M.; Jochemsen, R.; Statt, B.; Kubik, P.; Marsolais, R.; Berlinsky, A.; Landesman, A.

    1980-01-01

    Using a pulsed low temperature discharge in a closed cell containing H2 and 4He, we have been able to store a low density (~ 1012 atoms/cc) gas of atomic hydrogen for periods of order one hour in zero magnetic field and T ? 1 K. Pulsed magnetic resonance at the 1420 MHz hyperfine transition has been used to study a number of the properties of the gas, including the recombination rate H + H + 4He ? H2 + 4He, the hydrogen spin-exchange relaxation rates, the diffusion coefficient of H in 4He...

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

    International Nuclear Information System (INIS)

    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 (MEPsteam). The valve closing timing for maximum MEPsteam 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 MEPsteam calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEPcombustion) 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.

  9. Technical assessment of gas turbine cycle for high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The gas turbine cycle appears to be the best near-term power conversion method for the high temperature gas-cooled reactor (HTGR). The author extensively investigates the gas turbine cycle including direct cycle, open indirect cycle and closed indirect cycle with medium of helium, nitrogen and air. Each cycle is analyzed and optimized from the thermodynamic standpoint and its turbo-machine is aerodynamically designed. As a result, the direct cycle with helium is an ideal option for the HTGR gas turbine cycle; however it is not easy to be realized based on current technology. The closed indirect cycle with helium or nitrogen is a practical one at present time, which can get the gas turbine cycle and lay technical bases for the future direct cycle

  10. 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 smover 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)

  11. Feasibility study on different gas turbine cycles for high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    There is growing global interest in modular High Temperature Gas-cooled Reactor (HTGR), due to its attractive features of enhanced safety. Meanwhile, the gas turbine cycle (Brayton cycle) appears to be the best near-term power conversion method for maximizing the economic potential of modular HTGR. Therefore the modular HTGR coupled with the gas turbine cycle is considered as one of the leading candidate concepts for future nuclear power deployment. In this paper, several typical gas turbine cycles for modular HTGRs are investigated theoretically, including close direct cycle (using helium as the working fluid), closed indirect cycle (using helium or nitrogen) and open indirect cycle (using air). Key factors affecting the efficiency of a cycle include the turbine inlet temperature, compressor and turbine adiabatic efficiencies, recuperator effectiveness and cycle fractional pressure loss. These parameters and their effects on the cycle performance are examined in detail. Each cycle is analyzed and optimized from the thermodynamic point of view and its turbocompressor, one of the most important components for the cycle, is aerodynamically designed. As a result, the closed direct cycle using helium as the working fluid is an ideal cycle for the modular HTGR gas turbine cycle; however it is not easy to be realized based on current technology. And the closed indirect cycle using helium or nitrogen is a practical one now; it can realize the gas turbine cycle method and makalize the gas turbine cycle method and make the technical bases for the future direct cycle. (author)

  12. Exhaust gas emissions from various automotive fuels for light-duty vehicles. Effects on health, environment and energy utilization

    International Nuclear Information System (INIS)

    The main aim of the investigation has been to assess the effects on health and environment from various alternative fuels for light-duty vehicles. Effects that can be identified and quantified, such as acidification, ozone formation, cancer risk and climate change, have been of primary interest but other effects, such as respiratory diseases, have also been investigated. Data have been collected through literature surveys for subsequent calculation of the mentioned effects in different time-frames. Corrections have been used to take into consideration the influence of climate, ageing and driving pattern. Emissions generated in fuel production have also been accounted for. The most significant and important differences between the fuels have been found for effects as ozone formation cancer risk and particulate emissions. Alternative fuels, such as methanol and methane (natural gas and biogas), significantly decrease the ozone formation in comparison to petrol, while ethanol, methanol and methane are advantageous concerning cancer risk. The particulate emissions are considerably higher for diesel engines fuelled by diesel oil and RME in comparison to the other fuels. In the future, the importance of acid emissions in the fuel production will increase since the NOx and SOx emissions will decrease from the vehicles. The emissions of climate gases could be significantly reduced by using non-fossil fuels but the efficiency of the drive train is also of importance. The technical development potential for further emission reductions is considerable for all fuels but the advantage for the best fuel options will remain in the future

  13. IAEA high temperature gas-cooled reactor activities

    International Nuclear Information System (INIS)

    The IAEA activities on high temperature gas-cooled reactors are conducted with the review and support of the Member states, primarily through the International Working Group on Gas-Cooled Reactors (IWG-GCR). This paper summarises the results of the IAEA gas-cooled reactor project activities in recent years along with ongoing current activities through a review of Co-ordinated Research Projects (CRPs), meetings and other international efforts. A series of three recently completed CRPs have addressed the key areas of reactor physics for LEU fuel, retention of fission products and removal of post shutdown decay heat through passive heat transport mechanisms. These activities along with other completed and ongoing supporting CRPs and meetings are summarised with reference to detailed documentation of the results. (authors)

  14. Power Conversion Study for High Temperature Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    The Idaho National Laboratory (INL) is investigating a Brayton cycle efficiency improvement on a high temperature gas-cooled reactor (HTGR) as part of Generation-IV nuclear engineering research initiative. There are some technical issues to be resolved before the selection of the final design of the high temperature gas cooled reactor, called as a Next Generation Nuclear Plant (NGNP), which is supposed to be built at the INEEL by year 2017. The technical issues are the selection of the working fluid, direct vs. indirect cycle, power cycle type, the optimized design in terms of a number of intercoolers, and others. In this paper, we investigated a number of working fluids for the power conversion loop, direct versus indirect cycle, the effect of intercoolers, and other thermal hydraulics issues. However, in this paper, we present part of the results we have obtained. HYSYS computer code was used along with a computer model developed using Visual Basic computer language

  15. Temperature and solids effect on gas?liquid mass transfer

    OpenAIRE

    Ferreira, Anto?nio; Ferreira, Ceci?lia; Rocha, F. A.; Teixeira, J. A.

    2009-01-01

    The temperature and solids effect on the mass transfer characteristics in a bubble column was studied experimentally for the systems air/water/polyvinyl chloride (PVC) beads and air/water/expandable polystyrene (EPS) beads. Volumetric liquid side mass transfer coefficient, kLa, was determined under different temperatures (20, 25, 30, 35ºC), solid concentrations (up to 5%), gas flow rates (up to 7.4 mm/s) and solid sizes (549 and 210 ?m for PVC beads, and 591 ?m for EPS beads...

  16. High temperature gas cooled reactor steam-methane reformer design

    International Nuclear Information System (INIS)

    The concept of the long distance transportation of process heat energy from a High Temperature Gas Cooled Reactor (HTGR) heat source, based on the steam-methane reforming reaction, is being evaluated by the Department of Energy as an energy source/application for use early in the 21st century. This paper summaries the design of a helium heated steam reformer utilized in conjunction with an intermediate loop, 850/degree/C reactor outlet temperature, HTGR process heat plant concept. This paper also discusses various design considerations leading to the mechanical design features, the thermochemical performance, the materials selection and the structural design analysis. 12 refs

  17. Transport Properties of Superfluid Dipolar Fermi Gas at Low Temperatures

    OpenAIRE

    Maryam Khademi Dehkordi

    2014-01-01

    Transport coefficients of superfluid dipolar Fermi gas are calculated by using the Boltzmann equation approach. The interaction between Bogoliubov-Bogoliubov quasiparticles in the collision integral is considered in binary process. The shear viscosities nxz? = nyy?,nxy?; nxz? ? nyz?; and nu? are proportional to T-6; T-8; and T-10 , respectively. Also, we have found the elements of the diffusive thermal conductivities Kxx?= Kyy? with temperature dependency T-5 and Ku? ...

  18. Gearbox Scheme in High Temperature Reactor Helium Gas Turbine System

    OpenAIRE

    Sheng Liu; Xuanyu Sheng

    2012-01-01

    Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed required by the generator. Three optional gearbox schemes are discussed. The first is single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. I...

  19. Experimental study of gas turbine combustion with elevated fuel temperatures

    Science.gov (United States)

    Wiest, Heather K.

    Many thermal management challenges have developed as advancements in gas turbine engine designs are made. As the thermal demands on gas turbine engines continue to increase, the heat sink available in the combustor fuel flow becomes more attractive. Increasing the temperature of fuel by using it as a heat sink can lead to higher combustion efficiency due to the increase in flow enthalpy and improved vaporization of the heated fuel. Emissions levels can also be affected by using heated fuels with the levels of carbon monoxide and unburned hydrocarbons tending to decrease while the amount of the oxides of nitrogen tends to increase. Although there are several benefits associated with using heated fuels in gas turbine engines, some problems can arise from their use including combustion instabilities, flashing within the fuel injector, and fuel coking or deposit formation within the fuel system. Various deoxygenation methods have been created to address the coking problem seen when using heated fuels. In the Gas Turbine Test Cell of the High Pressure Laboratory at Purdue University's Maurice J. Zucrow Laboratories, a 5 MW combustion rig was developed to complete combustion test with heated fuels. The facility's supply systems including heated air, jet fuel, cooling water, and nitrogen were designed and integrated to produce simulated engine conditions within the combustion rig. Heating capabilities produced fuel temperatures ranging up to 600 deg F. Testing was completed with two fuel deoxygenation methods: nitrogen sparging and catalytic deoxygenation. Results from the testing campaign included conventional pressure, temperature, and fuel property measurements; however, the most important measurements were the emissions samples that were analyzed for each test condition. Levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen were determined as well as the combustion efficiency calculated from these emissions measurements. The trends in emissions and performance from the increase in fuel temperature will be discussed. In addition, high frequency pressure data were recorded during testing to monitor combustion instabilities. Fuel samples were also taken and analyzed to document the changes in the volatile composition of the fuel from the two deoxygenation methods. The testing campaign was extremely successful. All project objectives were met with the heated fuel testing campaign. The combustion rig was run safely with fuel temperature up to 600 deg F, allowing the effects of elevated fuel temperatures on the performance and emissions of a gas turbine combustor to be evaluated as planned.

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

    OpenAIRE

    Gerasimov Alexander V.; Kirpichnikov Alexander P.; Rachevsky Leonid A.

    2013-01-01

    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 co...

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

    International Nuclear Information System (INIS)

    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 high temperature 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.

  2. Determination of gas temperature and density by measuring ultraviolet gas absorption at two wavelengths

    International Nuclear Information System (INIS)

    A technique is described which demonstrates how deployment of two different uv wavelengths may be utilized in absorption measurements to simultaneously derive both the temperature and number density of a gas. A mathematical formulation is presented which defines how one can estimate the sensitivity of the technique

  3. Turbomachinery for the gas-turbine high-temperature gas-cooled reactor power plant

    International Nuclear Information System (INIS)

    The Gas Turbine (or Direct Cycle) High-Temperature Gas-Cooled Reactor (HTGR) power plant uses a closed-cycle gas turbine directly in the primary coolant circuit of a helium-cooled high-temperature nuclear reactor. Previous papers have described configuration studies leading to the selection of a reactor and power conversion loop layout and the considerations affecting the design of the components of the power conversion loop. This paper discusses briefly the effects of the helium working fluid and the reactor cooling loop environment on the design requirements of the direct-cycle turbomachinery and describes the mechanical arrangement of a typical turbomachine for this application. The aerodynamic design is outlined, and the mechanical design is described in some detail, with particular emphasis on the bearings and seals for the turbomachine

  4. Corrosion of Alloy 617 in high-temperature gas environments

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Tsung-Kuang [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Chang, Hao-Ping [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Wang, Mei-Ya, E-mail: meywang@mx.nthu.edu.tw [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 300, Taiwan (China); Yuan, Trai [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Kai, Ji-Jung [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan (China)

    2014-05-01

    High-temperature gas-cooled reactors (HTGRs) with helium gas as the primary coolant have been considered as one type of the Generation IV nuclear power reactor systems. Several nickel-based superalloys, including Alloy 617, are potential structural materials to serve as pressure boundary components, such as the intermediate heat exchanger (IHX) in an HTGR. Impurities in a helium coolant, such as H{sub 2}O and O{sub 2}, can interact with structural materials at working temperatures of >900 °C, leading to serious degradation on these materials. In addition, defects in IHX surface coatings would allow these species to reach and interact with the external surfaces of these components, leading to similar or even more serious degradation. In this study we investigated the oxidation behavior of Alloy 617 in high-temperature, gaseous environments with various levels of O{sub 2} and H{sub 2}O. A series of general corrosion tests were conducted at test temperatures of 650 °C, 750 °C, 850 °C and 950 °C under various coolant compositions of dry air, 1% O{sub 2}, 10% relative humidity (RH), and 50% RH. Preliminary results showed that the surface morphologies of the Alloy 617 samples exhibited distinct evidence of intergranular corrosion. Compact chromium oxide layers were observed on the sample surfaces. The oxidation mechanisms of this alloy in the designated environments are discussed.

  5. 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.)

  6. Corrosion of Alloy 617 in high-temperature gas environments

    International Nuclear Information System (INIS)

    High-temperature gas-cooled reactors (HTGRs) with helium gas as the primary coolant have been considered as one type of the Generation IV nuclear power reactor systems. Several nickel-based superalloys, including Alloy 617, are potential structural materials to serve as pressure boundary components, such as the intermediate heat exchanger (IHX) in an HTGR. Impurities in a helium coolant, such as H2O and O2, can interact with structural materials at working temperatures of >900 °C, leading to serious degradation on these materials. In addition, defects in IHX surface coatings would allow these species to reach and interact with the external surfaces of these components, leading to similar or even more serious degradation. In this study we investigated the oxidation behavior of Alloy 617 in high-temperature, gaseous environments with various levels of O2 and H2O. A series of general corrosion tests were conducted at test temperatures of 650 °C, 750 °C, 850 °C and 950 °C under various coolant compositions of dry air, 1% O2, 10% relative humidity (RH), and 50% RH. Preliminary results showed that the surface morphologies of the Alloy 617 samples exhibited distinct evidence of intergranular corrosion. Compact chromium oxide layers were observed on the sample surfaces. The oxidation mechanisms of this alloy in the designated environments are discussed

  7. Variations of the gas temperature in He/N2 barrier discharges

    International Nuclear Information System (INIS)

    For obtaining the gas temperature in the micro-discharge areas and in the ambient gas of dielectric barrier discharges in helium/nitrogen mixtures we have studied the rotational temperature of the emission of molecular nitrogen ions

  8. Gas flow in vertical slots with large horizontal temperature differences

    International Nuclear Information System (INIS)

    Perfect gas exact solutions to the steady Navier--Stokes equations are given for laminar convective motion in open and closed vertical slots with large temperature differences using Sutherland law transport properties. The solutions are valid a few slot widths away from the ends in the asymptotic region where the opposite hot and cold wall boundary layers are fully merged. It is found that the static pressure (in the closed slot) and temperature and velocity distributions (in all cases) are very sensitive to property variations, even though the heat flux may not be. We observe the net horizontal and vertical heat fluxes to be the same as those obtained from the Boussinesq equations. Comparisons with constant property solutions and the well-known Boussinesq limiting solution for small temperature differences are given for examples using air

  9. The temperature dependence of the gas gain in sealed proportional counters

    International Nuclear Information System (INIS)

    The temperature dependence of the gas gain in sealed proportional counters has been studied. It is found that the temperature coefficient of the gas gain can be explained by the thermal expansion of the counter materials. A simple model for the temperature coefficient, based on the Diethorn gas amplification formula, is presented. Abnormal temperature coefficients, attributed to impurities present in the counter gas, have been found in some individual counters. (orig.)

  10. 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 ethanolthe 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

  11. 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.

  12. Gas flow in open vertical slots with large horizontal temperature differences and arbitrary external temperature

    International Nuclear Information System (INIS)

    Exact solutions to the steady Navier-Stokes equations are given for laminar convective motion in open vertical slots immersed in a perfect gas. The solutions are for large temperature differences using Sutherland law transport properties and an arbitrary external temperature. The solutions are valid in the fully developed region where the opposite hot and cold vertical wall boundary layers are fully merged. It is found that the temperature, velocity, mass flow rate, and vertical heat flux are very sensitive to property variations, even though the horizontal heat flux is not. Furthermore, it is found that if only one end of the slot is open, the velocity and vertical heat flux are independent of the external temperature. Comparisons with constant transport property solutions and the well-known Boussinesq limiting solution for small temperature differences are given for examples using air or hydrogen; these show that important but significantly different effects exist as a result of density and transport property variations

  13. 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.

  14. Evaluation of high-temperature alloys for helium gas turbines

    International Nuclear Information System (INIS)

    Because of the high thermal and mechanical stresses in components of a helium turbine coupled directly to a high-temperature reactor and the stringent nuclear safety requirements, an extensive materials development program has been undertaken. The candidate alloys for turbine blades and hot ducts (nickel and molybdenum-base alloys) and for rotors (1% CrMoV and 12% chromium steels) have been tested under the expected service conditions. The results of creep/rupture, fatigue, and fracture mechanics tests on turbine blade and rotor materials are presented. The gas/metal reactions that occur in the simulated reactor coolant gas and the decontamination behavior of components are also discussed. In addition the development of a molybdenum-base alloy for turbine blading is reported

  15. Evaluation of high-temperature alloys for helium gas turbines

    International Nuclear Information System (INIS)

    Because of the high thermal and mechanical stresses in components of a helium turbine coupled directly to a high-temperature reactor and the stringent nuclear safety requirements, an extensive materials development program has been undertaken. The candidate alloys for turbine blades and hot ducts (nickeland molybdenum-base alloys) and for rotors (1% CrMoV and 12% chromium steels) have been tested under the expected service conditions. The results of creep/rupture, fatigue, and fracture mechanics tests on turbine blade and rotor materials are presented. The gas/metal reactions that occur in the simulated reactor coolant gas and the decontamination behavior of components are also discussed. In addition the development of a molybdenum-base alloy for turbine blading is reported

  16. New high temperature gas flow cell developed at ISIS

    International Nuclear Information System (INIS)

    A flow-through quartz gas cell, together with a gas flow control and monitoring system, has been designed and constructed at ISIS. This equipment allows neutron powder diffraction data to be collected on samples at temperatures up to around 1300 K when exposed to user chosen mixtures of O2, Ar, CO2, and CO. By exploiting the sensitivity of neutrons to the presence of light atoms such as oxygen, it is possible to probe the crystal structure of oxide materials as a function of oxygen partial pressures down to log10p(O2) of about -20. The resultant structural information can then be correlated with the bulk properties of the materials, whose research and technological interests lie in fields such as energy production, storage materials, catalysis, and earth science.

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

    Science.gov (United States)

    Sockol, P. M.

    1973-01-01

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

  18. Brayton Cycle for High Temperature Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    This paper describes research on improving the Brayton cycle efficiency for a high-temperature gas-cooled reactor (HTGR). In this study, we are investigating the efficiency of an indirect helium Brayton cycle for the power conversion side of an HTGR power plant. A reference case based on a 250-MW(thermal) pebble bed HTGR was developed using helium gas as a working fluid in both the primary and power conversion sides. The commercial computer code HYSYS was used for process optimization. A numerical model using the Visual-Basic (V-B) computer language was also developed to assist in the evaluation of the Brayton cycle efficiency. Results from both the HYSYS simulation and the V-B model were compared with Japanese calculations based on the 300-MW(electric) Gas Turbine High-Temperature Reactor (GTHTR) that was developed by the Japan Atomic Energy Research Institute. After benchmarking our models, parametric investigations were performed to see the effect of important parameters on the cycle efficiency. We also investigated single-shaft versus multiple-shaft arrangements for the turbomachinery. The results from this study are applicable to other reactor concepts such as fast gas-cooled reactors, supercritical water reactors, and others. The ultimate goal of this study is to use other fluids such as supercritical carbon dioxide for the HTGR power conversion loop in order to improve the cycle efficiency over that of the helium Brayton cycle. This study is in progress, and thn cycle. This study is in progress, and the results will be published in a subsequent paper

  19. Brayton Cycle for High-Temperature Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    This paper describes research on improving the Brayton cycle efficiency for a high-temperature gas-cooled reactor (HTGR). In this study, we are investigating the efficiency of an indirect helium Brayton cycle for the power conversion side of an HTGR power plant. A reference case based on a 250-MW(thermal) pebble bed HTGR was developed using helium gas as a working fluid in both the primary and power conversion sides. The commercial computer code HYSYS was used for process optimization. A numerical model using the Visual-Basic (V-B) computer language was also developed to assist in the evaluation of the Brayton cycle efficiency. Results from both the HYSYS simulation and the V-B model were compared with Japanese calculations based on the 300-MW(electric) Gas Turbine High-Temperature Reactor (GTHTR) that was developed by the Japan Atomic Energy Research Institute. After benchmarking our models, parametric investigations were performed to see the effect of important parameters on the cycle efficiency. We also investigated single-shaft versus multiple-shaft arrangements for the turbomachinery. The results from this study are applicable to other reactor concepts such as fast gas-cooled reactors, supercritical water reactors, and others.The ultimate goal of this study is to use other fluids such as supercritical carbon dioxide for the HTGR power conversion loop in order to improve the cycle efficiency over that of the helium Brayton cycle. This study is in progress, and the cycle. This study is in progress, and the results will be published in a subsequent paper

  20. Real Time Diagnostics of Jet Engine Exhaust Plumes Using a Chirped QC Laser Spectrometer

    Science.gov (United States)

    Hay, K. G.; Duxbury, G.; Langford, N.

    2010-06-01

    Quantitative measurements of real-time variations of the chemical composition of a jet engine exhaust plume is demonstrated using a 4.86 ?mn intra-pulse quantum cascade laser spectrometer. The measurements of the gas turbine exhaust were carried out in collaboration with John Black and Mark Johnson at Rolls Royce. The recording of five sets of averaged spectra a second has allowed us to follow the build up of the combustion products within the exhaust, and to demonstrate the large variation of the integrated absorption of these absorption lines with temperature. The absorption cross sections of the lines of both carbon monoxide and water increase with temperature, whereas those of the three main absorption lines of carbon dioxide decrease. At the steady state limit the absorption lines of carbon dioxide are barely visible, and the spectrum is dominated by absorption lines of carbon monoxide and water.

  1. Cogeneration applications of high temperature gas-cooled reactors

    International Nuclear Information System (INIS)

    The high-temperature gas-cooled reactor (HTGR) is an advanced, highefficiency reactor system which can play a vital role in meeting the future energy needs of the nation by contributing not only to the generation of electric power, but also to the industrial energy sector traditionally served by fossil fuels. Most energy-intensive industrial processes require considerable process steam and electric power. The HTGR-steam cycle/cogeneration system is uniquely suited to provide the required steam and electric power for such applications. This paper reviews generic and site-specific HTGR cogeneration application study results and describes the integrated and modular HTGR designs used for such applications

  2. 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.)

  3. Transport Properties of Superfluid Dipolar Fermi Gas at Low Temperatures

    Directory of Open Access Journals (Sweden)

    Maryam Khademi Dehkordi

    2014-03-01

    Full Text Available Transport coefficients of superfluid dipolar Fermi gas are calculated by using the Boltzmann equation approach. The interaction between Bogoliubov-Bogoliubov quasiparticles in the collision integral is considered in binary process. The shear viscosities nxz? = nyy?,nxy?; nxz? ? nyz?; and nu? are proportional to T-6; T-8; and T-10 , respectively. Also, we have found the elements of the diffusive thermal conductivities Kxx?= Kyy? with temperature dependency T-5 and Ku? which is proportional to T-7 and other components which are zero.

  4. 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)

  5. Power Conversion Study for High Temperature Gas-Cooled Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chang Oh; Richard Moore; Robert Barner

    2005-05-01

    The Idaho National Laboratory (INL) is investigating a Brayton cycle efficiency improvement on a high temperature gas-cooled reactor (HTGR) as part of Generation-IV nuclear engineering research initiative. There are some technical issues to be resolved before the selection of the final design of the high temperature gascooled reactor, called as a Next Generation Nuclear Plant (NGNP), which is supposed to be built at the INEEL by year 2017. The technical issues are the selection of the working fluid, direct vs. indirect cycle, power cycle type, the optimized design in terms of a number of intercoolers, and others. In this paper, we investigated a number of working fluids for the power conversion loop, direct versus indirect cycle, the effect of intercoolers, and other thermal hydraulics issues. However, in this paper, we present part of the results we have obtained. HYSYS computer code was used along with a computer model developed using Visual Basic computer language.

  6. Heat transfer analysis of a finned-tube evaporator for engine exhaust heat recovery

    International Nuclear Information System (INIS)

    Highlights: ? The characteristic of the exhaust waste heat for a light duty diesel engine is analyzed. ? A mathematical model is established for a finned-tube evaporator used in an ORC. ? The heat transfer performance of the finned-tube evaporator is evaluated throughout the engine’s operating region. - Abstract: The organic Rankine cycle (ORC) can be used to recover waste heat from an internal combustion engine. In such a system, the evaporator design is critical. Determining the amount of heat that can be transferred in a designed evaporator is extremely important for a successful ORC system. In this paper, the performance of a finned-tube evaporator used to recover exhaust waste heat from a diesel engine is presented. First, the exhaust heat of the chosen diesel engine is evaluated based on the measured data. Subsequently, a mathematical model of the evaporator is created based on the detailed geometry and the specific ORC working conditions. Then, the heat transfer of the evaporator is estimated as the diesel engine runs through all of its operating regions defined by the engine speed and the engine load. The results show that the exhaust temperature at the evaporator outlet increases with engine speed and engine load. Although the convective heat transfer coefficient of the organic working fluid is significantly larger than that of the exhaust gas, the overall heat transfer coefficient is slightly greater than that of the exhaust gas. Furthermore, the hea exhaust gas. Furthermore, the heat transfer rate is the greatest in the preheated zone and least in the superheated zone. Consequently, the heat transfer area for the preheated zone is nearly half of the total area. In addition, the area of the superheated zone is slightly greater than that of the two-phase zone. It is concluded that the heat transfer area for a finned tube evaporator should be selected carefully based on the engine’s most typical operating region.

  7. Hot exhaust gases with passive FTIR emission spectroscopy

    Science.gov (United States)

    Heland, Joerg; Schaefer, Klaus; Haus, Rainer

    1998-12-01

    Passive FTIR emission spectroscopy using a commercial medium resolution instrument with a telescope has been applied to analyze the hot exhaust gases of various combustion sources, such as industrial and building smoke stacks, aircraft engines, flares, and forest fires. To interpret the remotely measured spectra a multi-layer, line-by-line spectra retrieval software using the molecular spectral databases HITRAN and HITEMP has been developed, validated and successfully used to determine the exhaust gas temperatures and the concentrations of CO2, H2O, CO, N2O, CH4, NO, NO2, SO2, and HCl for different combustion conditions of the sources. In this paper the feasibility and the setup of passive IR measurements, the basic theory of radiative transfer and special features of the commercially available spectra analysis code are described. In addition, the results of the different measurement applications are summarized.

  8. Characteristics of impact-generated plasma with different electron temperature and gas temperature

    Science.gov (United States)

    Li, Jianqiao; Song, Weidong; Ning, Jianguo; Tang, Huiping

    2014-07-01

    The characteristics of the plasma with difference between the electron temperature and gas temperature were investigated and the relationship between the plasma ionization degree and the internal energy of a system was obtained. A group of equations included the chemical reaction equilibrium equation, the chemical reaction rate equation and the energy conservation equation were adopted to calculate the electron density, the electron temperature and the atom temperature with a given internal energy. These equations combined with Navier-Stokes (N-S) equations is solved by a smooth particle hydrodynamic (SPH) code. The charges generated in hypervelocity impacts with five different velocities are calculated and verified with the empirical formulas. The influence of a critical velocity for plasma generation is considered in the empirical formula and the parameters are fitted by the numerical results. By comparing with the results in reference, the fitted new empirical formula is verified to be reasonable and useful for a wide range of impact velocity.

  9. High temperature gas-cooled reactor and its applications

    International Nuclear Information System (INIS)

    The contribution of nuclear power will become much greater to the protection of terrestrial environment as well as in the energy supply, if nuclear power is used not only for electricity production but also for non-electricity production such as process heat in the chemical industry. Great attention is paid to High Temperature Gas-cooled Reactor (HTGR), since it can produce high temperature heat of nearly 1,000degC and also it has very high inherent safety. The high temperature heat produced by the HTGR can be supplied as process heat to the various industries such as crude oil recovery, oil refinery, petroleum chemistry, coal chemistry, iron manufacture, hydrogen production by thermo-chemical process and aluminium oxide production from bauxite. Furthermore, the heat can be used for co-generation of electric power and heat and also for various purposes, from high temperature region to low temperature region in the cascade system, since temperature of the heat produced by HTGR is very high. It is possible to attain total heat utilization efficiency of 80% in the cascade system. The technical problems to be solved in the nuclear heat application to chemical industry are existing limitations in operation and licensing rules in relation to connecting the nuclear reactor with chemical plants, while the process, itself, is technically feasible. The most advantageous applications at present are in crude oil recovery, oil refinery and aluminium oxide production, and nuclear h aluminium oxide production, and nuclear heat application will become economically competitive with conventional oil-fired heat in various industries by around 2020. (author)

  10. Research of autoignition temperature in high-temperature oxidizer during natural gas combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wilk, Ryszard K.; Werle, Sebastian [Sielsian Univ. of Tchnology, Gliwice (Poland). Inst. of Thermal Technology

    2006-01-15

    HTAC technology is one of the biggest achievement of combustion technologies in last few years. Owning to it we can improve energetic efficiency and reduce of NO{sub x} and CO emission. In this paper experimental tests of fuel gas autoignition process in high-temperature oxidizer have been carried out. For this purpose special experimental stand was designed and build and the first results were presented.

  11. Working gas temperature and pressure changes for microscale thermal creep-driven flow caused by discontinuous wall temperatures

    International Nuclear Information System (INIS)

    Microscale temperature gradient-driven (thermal creep/transpiration) gas flows have attracted significant interest during the past decade. For free molecular and transitional conditions, applying temperature gradients to a flow channel's walls induces the thermal creep effect. This results in a working gas flowing through the channel from cold to hot, which is generally accompanied by a rising pressure from cold to hot in the channel. Working gas temperature and pressure distributions can vary significantly, depending on a flow channel's configuration and wall temperature distribution. Understanding working gas temperature excursions, both increases and decreases, is essential to ensure the effective use of thermal creep flows in microscale applications. In this study, the characterizations of working gas temperature variations, due to both temperature discontinuities and more gradual changes, on a variety of flow channel walls, were systematically investigated using the direct simulation Monte Carlo (DSMC) method. A micro/meso-scale pump, the Knudsen compressor, was chosen to illustrate the importance of controlling working gas temperature in thermal creep-driven flows. Gas pressure and temperature variations, through several Knudsen compressor stage configurations, were studied to determine the most advantageous flow phenomena for the efficient operation of Knudsen compressors.

  12. Effect of low temperature gas nitriding and low temperature gas carburizing on high cycle fatigue property in SUS316L

    International Nuclear Information System (INIS)

    It is known that nitrogen and carbon S phases are formed in the diffusion layer on the surface of austenitic stainless steels if nitriding or carburizing is performed at the temperature of 500degC or less. In order to investigate the effect of the nitrogen and carbon S phases on high cycle fatigue properties of type316L austenitic stainless steel, rotating bending fatigue tests were carried out for four specimens with different treatments: One was gas carburized at 470degC. The other three were gas nitrided at 420degC, 460degC and 570degC, respectively. The former three specimens had the carbon or the nitrogen S phase and the last one had no S phase in the diffusion layer, depending on the temperature. As the fatigue tests result, the S phase is effective to enhance the fatigue properties. The effect of fatigue properties improvement of the nitrogen S phase is greater than that of the carbon S phase. The fatigue strength increases with an increase in the thickness of the diffusion layer in the nitrided specimens. External observation suggests that the fatigue crack initiated from the chipped part on the surface due to fatigue loading. Although the chipping behavior depended on the diffusion species, the propagation behavior of fatigue cracks did not depend on them. (author)

  13. Hot streak characterization in serpentine exhaust nozzles

    Science.gov (United States)

    Crowe, Darrell S.

    Modern aircraft of the United States Air Force face increasingly demanding cost, weight, and survivability requirements. Serpentine exhaust nozzles within an embedded engine allow a weapon system to fulfill mission survivability requirements by providing denial of direct line-of-sight into the high-temperature components of the engine. Recently, aircraft have experienced material degradation and failure along the aft deck due to extreme thermal loading. Failure has occurred in specific regions along the aft deck where concentrations of hot gas have come in contact with the surface causing hot streaks. The prevention of these failures will be aided by the accurate prediction of hot streaks. Additionally, hot streak prediction will improve future designs by identifying areas of the nozzle and aft deck surfaces that require thermal management. To this end, the goal of this research is to observe and characterize the underlying flow physics of hot streak phenomena. The goal is accomplished by applying computational fluid dynamics to determine how hot streak phenomena is affected by changes in nozzle geometry. The present research first validates the computational methods using serpentine inlet experimental and computational studies. A design methodology is then established for creating six serpentine exhaust nozzles investigated in this research. A grid independent solution is obtained on a nozzle using several figures of merit and the grid-convergence index method. An investigation into the application of a second-order closure turbulence model is accomplished. Simulations are performed for all serpentine nozzles at two flow conditions. The research introduces a set of characterization and performance parameters based on the temperature distribution and flow conditions at the nozzle throat and exit. Examination of the temperature distribution on the upper and lower nozzle surfaces reveals critical information concerning changes in hot streak phenomena due to changes in nozzle geometry.

  14. New deployment of high temperature gas-cooled reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sekimoto, Hiroshi [Tokyo Inst. of Tech. (Japan); Tsuchie, Yasuo [Japan Atomic Power Co., Tokyo (Japan); Kunitomi, Kazuhiko; Shiozawa, Shusaku; Konuki, Kaoru; Inagaki, Yoshiyuki [Japan Atomic Energy Research Inst., Tokyo (Japan); Hayakawa, Hitoshi [Fuji Electric Co. Ltd., Tokyo (Japan)

    2002-12-01

    The high temperature gas-cooled reactor (HTGR) is now under a condition difficult to know it well, because of considering not only power generation, but also diverse applications of its nuclear heat, of having extremely different safe principle from that of conventional reactors, of having two types of pebble-bed and block which are extremely different types, of promoting its construction plan in South Africa, of including its application to disposition of Russian surplus weapons plutonium of less reporting HTTR in Japan in spite of its full operation, and so on. However, HTGR is expected for an extremely important nuclear reactor aiming at the next coming one of LWR. HTGR which is late started and developed under complete private leading, is strongly conscious at environmental problem since its beginning. Before 30 years when large scale HTGR was expected to operate, it advertised a merit to reduce wasted heat because of its high temperature. As ratio occupied by electricity expands among application of energies, ratio occupied by the other energies are larger. When considering applications except electric power, high temperature thermal energy from HTGR can be thought wider applications than that from LWR and so on. (G.K.)

  15. New deployment of high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The high temperature gas-cooled reactor (HTGR) is now under a condition difficult to know it well, because of considering not only power generation, but also diverse applications of its nuclear heat, of having extremely different safe principle from that of conventional reactors, of having two types of pebble-bed and block which are extremely different types, of promoting its construction plan in South Africa, of including its application to disposition of Russian surplus weapons plutonium of less reporting HTTR in Japan in spite of its full operation, and so on. However, HTGR is expected for an extremely important nuclear reactor aiming at the next coming one of LWR. HTGR which is late started and developed under complete private leading, is strongly conscious at environmental problem since its beginning. Before 30 years when large scale HTGR was expected to operate, it advertised a merit to reduce wasted heat because of its high temperature. As ratio occupied by electricity expands among application of energies, ratio occupied by the other energies are larger. When considering applications except electric power, high temperature thermal energy from HTGR can be thought wider applications than that from LWR and so on. (G.K.)

  16. Metaphysics methods development for high temperature gas cooled reactor analysis

    International Nuclear Information System (INIS)

    Gas cooled reactors have been characterized as one of the most promising nuclear reactor concepts in the Generation-IV technology road map. Considerable research has been performed on the design and safety analysis of these reactors. However, the calculational tools being used to perform these analyses are not state-of-the-art and are not capable of performing detailed three-dimensional analyses. This paper presents the results of an effort to develop an improved thermal-hydraulic solver for the pebble bed type high temperature gas cooled reactors. The solution method is based on the porous medium approach and the momentum equation including the modified Ergun's resistance model for pebble bed is solved in three-dimensional geometry. The heat transfer in the pebble bed is modeled considering the local thermal non-equilibrium between the solid and gas, which results in two separate energy equations for each medium. The effective thermal conductivity of the pebble-bed can be calculated both from Zehner-Schluender and Robold correlations. Both the fluid flow and the heat transfer are modeled in three dimensional cylindrical coordinates and can be solved in steady-state and time dependent. The spatial discretization is performed using the finite volume method and the theta-method is used in the temporal discretization. A preliminary verification was performed by comparing the results with the experiments conducted at the SANA test facility. This facility is located at the Institute for Safety Research and Reactor Technology (ISR), Julich, Germany. Various experimental cases are modeled and good agreement in the gas and solid temperatures is observed. An on-going effort is to model the control rod ejection scenarios as described in the OECD/NEA/NSC PBMR-400 benchmark problem. In order to perform these analyses PARCS reactor simulator code will be coupled with the new thermal-hydraulic solver. Furthermore, some of the other anticipated accident scenarios in the benchmark require full three dimensional modeling and will be analyzed to include the malfunctioning of one of the de-fueling chutes and blockage of the helium flow channels in the side reflector at the PBMR-400 model

  17. Hyperventilation and exhaustion syndrome

    OpenAIRE

    Ristiniemi, Heli; Perski, Aleksander; Lyskov, Eugene; Emtner, Margareta

    2014-01-01

    Chronic stress is among the most common diagnoses in Sweden, most commonly in the form of exhaustion syndrome (ICD-10 classification – F43.8). The majority of patients with this syndrome also have disturbed breathing (hyperventilation). The aim of this study was to investigate the association between hyperventilation and exhaustion syndrome. Thirty patients with exhaustion syndrome and 14 healthy subjects were evaluated with the Nijmegen Symptom Questionnaire (NQ). The participants complete...

  18. 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.

  19. 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.

  20. An evaluation of small High Temperature Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    As a result of Congressional and utility initiatives the High Temperature Gas-Cooled Reactor Program in the U.S. was realigned in FY 1984 to consider the potential for Small (100 MWe - 400 MWe) HTGR's as a basis for overcoming the technical and institutional barriers that are currently preventing the deployment of nuclear systems. The evaluation process is being conducted on a rigorous basis that has included the definition of Utility/User Requirements, the development of criteria for selection and the application of a disciplined systems engineering methodology as a basis for the design. This paper summarizes the status of the design and evaluation process and addresses the prospects for Small HTGR's in the U.S

  1. Gearbox scheme in high temperature reactor helium gas turbine system

    International Nuclear Information System (INIS)

    Helium Turbine is used in High Temperature Reactor-helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed of the generator. Three optional gearbox schemes are discussed. (1) Single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. Its advantage is simple structure, easy to manufacture, and high reliability, while disadvantage is large volume and misalignment of input and output axle. (2) Planetary gear mechanism with static planet carrier. (3) Planetary gear mechanism with static internal gear. The latter two gearbox devices have similar structure. Their advantage is small volume and high reduction gear ratio, while disadvantage are complicated structure, many gears, low reliability and low mechanical efficiency. (author)

  2. Cogeneration economics of the high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The era of inexpensive energy is over. Further, solid fuel alternatives to fluid fuels for stationary power systems not only make sense from a National security rationale, by limiting the exposure of the economy to imported liquid hydrocarbons, but from an economic viewpoint, as well. The High Temperature Gas-Cooled Reactor (HTGR) is a nuclear option which is being developed to provide economic and reliable power. An economic analysis has been performed for a 2240 MWt HTGR Steam Cycle/Cogeneration plant (HTGR-SC/C). The cost of production decision measure was determined from estimated plant investment and operating costs, using a consistent set of economic ground rules and cost bases. The HTGR-SC/C cost of production was then compared with that of a pulverized coal cogenerator of comparable capabilities. Based upon this analysis, the HTGR-SC/C proved to be economically superior

  3. Seismic study on high temperature gas-cooled reactor core

    International Nuclear Information System (INIS)

    The resistance against earthquakes of a high temperature gas-cooled reactor (HTGR) core with block-type fuel is not yet fully ascertained. Seismic studies must be made if such a reactor plant is to be installed in the areas with frequent earthquakes. The experimental and analytical studies for the seismic response of the HTGR core were carried out. First, the fundamental behavior, such as the softening characteristic of a single stacked column (which is piled up with blocks) and the hardening characteristic with the block impact were clarified from the seismic experiments. Second, the displacement and the impact characteristics of the two-dimensional vertical core and the two-dimensional horizontal core were studied from the seismic experiments. Finally, analytical methods and computer programs for the seismic response of HTGR cores were developed. (author) 57 refs

  4. Hybrid simulation of high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    A hybrid simulator was made to calculate the dynamics of high temperature gas cooled reactor(VHTR). The continuous space-discrete time (CSDT) method is applied to solve the partial differential equations of the heat transfer in the hybrid computation. By this method the error of the heat balance is decreased to less than one percent in the steady state. Though the mini computer is used for this simulator, it operates about five times faster than real time. The dynamics of VHTR are characterized by the large heat capacity of the reactor core and the long time constant. The values of these parameters are reported as the results of this calculation. The control system of the reactivity and the coolant flow rate is required to operate the reactor. The nonlinearity of VHTR which occurs in the change of flow rate are also understood quantitatively by this simulator. (author)

  5. Assessment and status report High-Temperature Gas-Cooled Reactor gas-turbine technology

    International Nuclear Information System (INIS)

    Purpose of this report is to present a brief summary assessment of the High Temperature Gas-Cooled Reactor - Gas Turbine (HTGR-GT) technology. The focal point for the study was a potential 2000 MW(t)/800 MW(e) HTGR-GT commercial plant. Principal findings of the study were that: the HTGR-GT is feasible, but with significantly greater development risk than the HTGR-SC (Steam Cycle). At the level of performance corresponding to the reference design, no incremental economic incentive can be identified for the HTGR-GT to offset the increased development costs and risk relative to the HTGR-SC. The relative economics of the HTGR-GT and HTGR-SC are not significantly impacted by dry cooling considerations. While reduced cycel complexity may ultimately result in a reliability advantage for the HTGR-GT, the value of that potential advantage was not quantified

  6. Exergy analysis of gas turbine combined 100 MW high-temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    According to the design of 100 MW High-Temperature Gas-Cooled Reactor coupled with gas turbine, the energy and Exergy analysis were carried out for each part of the cycle, and inlet and outlet Exergies of those parts were calculated. The Exergy loss distribution and Exergy loss ratio of each sub-process were quantified and compared with the results of energy analysis. The results show that more than a half of the Exergy loss takes place inside the reactor core, while the compress system composed of low and high pressure compressors as well as the intercooler play a much smaller role in the contribution of Exergy losses than the results in the energy analysis. The Exergy loss of the cycle is mainly due to the energy conversion and irreversible heat exchange. The total energy efficiency of the cycle is quite high, and the Exergy efficiency is higher. (authors)

  7. Temperature and Entropy Fields of Baryonic Gas in the Universe

    CERN Document Server

    He, P; Fang, L Z

    2004-01-01

    (Abridged)The temperature (T) and entropy (S) fields of baryonic gas/IGM are analyzed using simulation samples by a hybrid cosmological hydro/N-body code. We show that in the nonlinear regime the dynamical similarity between the IGM and dark matter will be broken by strong shocks. The heating and entropy production by the shocks make the IGM to be in multiple phases. The mean entropy, or the cosmological entropy floor, is found to be more than 100 h^(-1/3) keV cm^2 in all regions when z 50 h^(-1/3) keV cm^2) mostly resides in areas on scales larger than 1 h^(-1) Mpc and with density $\\rho_{dm}>10^2$. Therefore, gravitational shocks are an effective preheating mechanism of the IGM, and probably enough to provide the entropy excess of clusters and groups if the epoch of the gas falling in cluster cores is not earlier than z ~ 2 - 3. On the other hand, at redshifts z < 4, there is always more than 90% volume of the low dark matter mass density regions filled by the IGM with T < 10^4.5 K. Therefore, the mu...

  8. Analysis and description of the long-term creep behaviour of high-temperature gas turbine materials

    International Nuclear Information System (INIS)

    On a series of standard high-temperature gas turbine materials, creep tests were accomplished with the aim to obtain improved data on the long-term creep behaviour. The tests were carried out in the range of the main application temperatures of the materials and in the range of low stresses and elongations similar to operation conditions. They lasted about 5000 to 16000 h at maximum. At all important temperatures additional annealing tests lasting up to about 10000 h were carried out for the determination of a material-induced structure contraction. Thermal tension tests were effected for the description of elastoplastic short-time behaviour. As typical selection of materials the nickel investment casting alloys IN-738 LC, IN-939 and Udimet 500 for industrial turbine blades, IN-100 for aviation turbine blades and IN-713 C for integrally cast wheels of exhaust gas turbochargers were investigated, and also the nickel forge alloy Inconel 718 for industrial and aviation turbine disks and Nimonic 101 for industrial turbine blades and finally the cobalt alloy FSC 414 for guide blades and heat accumulation segments of industrial gas turbines. The creep tests were started on long-period individual creep testing machines with high strain measuring accuracy and economically continued on long-period multispecimen creep testing machines with long duration of test. The test results of this mixed test method were first subjected to a conventional evaluation in logarithmic time yieltional evaluation in logarithmic time yield and creep diagrams which besides creep strength curves provided creep stress limit curves down to 0.2% residual strain. (orig./MM)

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

    Science.gov (United States)

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

    1978-01-01

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

  10. Very-high-temperature gas reactor environmental impacts assessment

    International Nuclear Information System (INIS)

    The operation of a Very High Temperature Reactor (VHTR), a slightly modified General Atomic type High Temperature Gas-Cooled Reactor (HTGR) with 1600 F primary coolant, as a source of process heat for the 14000F steam-methanation reformer step in a hydrogen producing plant (via hydrogasification of coal liquids) was examined. It was found that: (a) from the viewpoint of product contamination by fission and activation products, an Intermediate Heat Exchanger (IHX) is probably not necessary; and (b) long term steam corrosion of the core support posts may require increasing their diameter (a relatively minor design adjustment). However, the hydrogen contaminant in the primary coolant which permeates the reformer may reduce steam corrosion but may produce other problems which have not as yet been resolved. An IHX in parallel with both the reformer and steam generator would solve these problems, but probably at greater cost than that of increasing the size of the core support posts. It is recommended that this corrosion problem be examined in more detail, especially by investigating the performance of current fossil fuel heated reformers in industry. Detailed safety analysis of the VHTR would be required to establish definitely whether the IHX can be eliminated. Water and hydrogen ingress into the reactor system are potential problems which can be alleviated by an IHX. These problems will require analysis, research and development within the program required for development of the VHTR

  11. Helium chemistry for high temperature gas-cooled reactors (Thesis)

    International Nuclear Information System (INIS)

    Chemistry control is important for the helium coolant of high-temperature gas-cooled reactors (HTGRs) because impurities cause oxidation of the graphite applied to the core structure and corrosion of high-temperature materials utilized at the intermediate heat exchanger (IHX). This thesis describes the helium chemistry which should be maintained adequately during reactor operations not only for the safety and stability of operations, but also for the increase of economic competitiveness by reducing replacing times of IHXs and simplifying helium purification systems. In this paper the chemical impurity behaviour was clarified by the obtained chemistry data by the Japan's HTTR and the criteria of chemical impurities for the GTHTR300C, which can supply both of electricity and hydrogen for the future hydrogen society, was proposed with its control technologies. In this R and D, the chemical impurity behavior, purification abilities, emitted impurities from graphite and thermal insulator, and hydrogen permeation at the heat transfer tubes of the IHX during the 950degC operation of the HTTR were evaluated. Utilizing these results, radical reactions at the core were identified. Also, chemical impurity criteria were proposed to avoid structural degradation of the Hastelloy XR and thermophysical properties deterioration at the heat transfer tubes. As a result, active chemistry control technologies where the necessary chemistry impurity will be injected in response to the chemical balance at the core are proposed for the GTHTR300C. The proposing technology is expected to contribute economically to the purification systems of the future HTGRs. (author)

  12. Evaluation of loss coefficient at exhaust junction for turbocharger matching calculation

    International Nuclear Information System (INIS)

    The suitability of the analysis for an unsteady compressible gas flow through an exhaust junction plays an important role in developing a computer program for the matching of a diesel engine to an exhaust turbocharger. The maximum momentary temperature differences between the lateral flow and the main flow at the junction is about 300 degrees C in an actual engine under operation. It is important to adopt boundary conditions compatible with the flow phenomena in order to improve the accuracy of the estimation of the exhaust energy. In previous works, the incompressible joining flow loss coefficients were employed in the computer program for the convenience of the calculation. In this study, the joining flow model of different kinds of gases has been assumed, and the flow loss coefficients are compared with incompressible ones. In this paper it is shown that the present results gives the precise boundary conditions for the computer program

  13. Corrosion behaviour of high temperature alloys in the cooling gas of high temperature reactors

    International Nuclear Information System (INIS)

    The reactive impurities in the primary cooling helium of advanced high temperature gas cooled reactors (HTGR) can cause oxidation, carburization or decarburization of the heat exchanging metallic components. By studies of the fundamental aspects of the corrosion mechanisms it became possible to define operating conditions under which the metallic construction materials show, from the viewpoint of technical application, acceptable corrosion behaviour. By extensive test programmes with exposure times of up to 30,000 hours, a data base has been obtained which allows a reliable extrapolation of the corrosion effects up to the envisaged service lives of the heat exchanging components. (author). 6 refs, 7 figs

  14. 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.

  15. Development of hot gas lines for high temperature reactors in the temperature range up to 9500C

    International Nuclear Information System (INIS)

    The process heat required for nuclear coal gasification is provided by helium circuits at 900 to 9500C and 40 to 50 bar. Whereas in the primary (nuclear) heat transfer system use is made of ceramic gas ducts of graphite or CFC (carbon fire-reinforced carbon), metallic gas ducts have found acceptance in the subsequent secondary systems. The high temperatures and pressure of the hot gas require either coaxial gas ducts and/or reliable internal insulation. Pressure and temperature loads must be strictly kept apart from each other. The requirements and constraints, the approaches adopted and their experimental confirmation are discussed in this article. (orig.)

  16. Measurement of unsteady gas temperature with optical fibre Fabry-Perot microsensors

    OpenAIRE

    Kilpatrick, Jm; Macpherson, Wn; Barton, Js; Jones, Jdc; Buttsworth, Dr; Jones, Tv; Chana, Ks; Anderson, Sj

    2002-01-01

    We describe the application of thin-film optical fibre Fabry-Perot (FFP) microsensors to high-bandwidth measurement of unsteady total temperature in transonic gas flows. An aerodynamic probe containing two temperature sensitive FFP microsensors was deployed in the rotor exit flow region of a gas turbine research rig. Measurements reveal gas temperature oscillations typically 4 K peak to peak at the blade passing frequency of 10 kHz with components to the third harmonic detected in the power s...

  17. Diagnosis of gas temperature, electron temperature, and electron density in helium atmospheric pressure plasma jet

    International Nuclear Information System (INIS)

    The optical emission spectra of helium atmospheric pressure plasma jet (APPJ) are captured with a three grating spectrometer. The grating primary spectrum covers the whole wavelength range from 200 nm to 900 nm, with the overlapped grating secondary spectrum appearing from 500 nm to 900 nm, which has a higher resolution than that of the grating primary spectrum. So the grating secondary spectrum of OH (A2? +(?? = 0) ? X2?(?? = 0)) is employed to calculate the gas temperature (Tg) of helium APPJ. Moreover, the electron temperature (Te) is deduced from the Maxwellian electron energy distribution combining with Tg, and the electron density (ne) is extracted from the plasma absorbed power. The results are helpful for understanding the physical property of APPJs.

  18. Use of exhaust gas energy in heavy trucks using the Rankine process; Nutzung der Abgasenergie von Nutzfahrzeugen mit dem Rankine-Prozess

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, Rainer; Geskes, Peter; Pantow, Eberhard; Eitel, Jochen [Behr GmbH and Co. KG, Stuttgart (Germany)

    2012-10-15

    Worldwide emissions legislation, rising fuel prices and future standards for CO{sub 2} emissions will also require further efforts to be made to reduce the fuel consumption of commercial vehicle engines, for example by optimising thermal management. In a joint project with its partners AVL and ZF, Behr has developed a system for the recuperation of exhaust heat that can reduce fuel consumption by approximately 5 %. (orig.)

  19. 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.

  20. 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.

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

    OpenAIRE

    Jafarmadara S.; Hosenzadeh M.B.

    2013-01-01

    This article investigates the improvement of operation characteristics and emissions reduction by means of creating an air-cell inside the piston body, exhaust gases recirculating and insulating combustion chamber in a direct injection diesel engine simultaneously. The engine considered is a caterpillar 3401 which was modeled with an air-cell included as part of the piston geometry. This air-cell demonstrates that air injection in late combustion period can be effective in a significant...

  2. 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 is a subject of interest.

  3. Parametric studies on different gas turbine cycles for a high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    The high temperature gas-cooled reactor (HTGR) coupled with turbine cycle is considered as one of the leading candidates for future nuclear power plants. In this paper, the various types of HTGR gas turbine cycles are concluded as three typical cycles of direct cycle, closed indirect cycle and open indirect cycle. Furthermore they are theoretically converted to three Brayton cycles of helium, nitrogen and air. Those three types of Brayton cycles are thermodynamically analyzed and optimized. The results show that the variety of gas affects the cycle pressure ratio more significantly than other cycle parameters, however, the optimized cycle efficiencies of the three Brayton cycles are almost the same. In addition, the turbomachines which are required for the three optimized Brayton cycles are aerodynamically analyzed and compared and their fundamental characteristics are obtained. Helium turbocompressor has lower stage pressure ratio and more stage number than those for nitrogen and air machines, while helium and nitrogen turbocompressors have shorter blade length than that for air machine

  4. 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.

  5. 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.

  6. Investigation and Optimization of the Acoustic Performance of Exhaust Systems

    OpenAIRE

    Elsaadany, Sara

    2012-01-01

    There is a strong competition among automotive manufacturers to reduce the radiated noise levels. One important source is the engine exhaust where the main noise control strategy is by using efficient mufflers. Stricter vehicle noise regulations combined with various exhaust gas cleaning devices, removing space for traditional mufflers, are also creating new challenges. Thus, it is crucial to have efficient models and tools to design vehicle exhaust systems. In addition the need to reduce CO2...

  7. 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

  8. Structural instabilities of high temperature alloys and their use in advanced high temperature gas cooled reactors

    International Nuclear Information System (INIS)

    High-temperature, iron-nickel and nickel based alloys are the candidate heat exchanger materials for advanced high temperature gas-cooled reactors supplying process heat for coal gasification, where operation temperatures can reach 850-950 deg. C and service lives of more than 100,000 h are necessary. In the present paper, typical examples of structural changes which occur in two representative alloys (Alloy 800 H, Fe-32Ni-20Cr and Alloy 617, Ni-22Cr-12Co-9Mo-1Al) during high temperature exposure will be given and the effects on the creep rupture properties discussed. At service temperatures, precipitation of carbides occurs which has a significant effect on the creep behaviour, especially in the early stages of creep when the precipitate particles are very fine. During coarsening of the carbides, carbides at grain boundaries restrict grain boundary sliding which retards the development of creep damage. In the service environments, enhanced carbide precipitation may occur due to the ingress of carbon from the environment (carburization). Although the creep rate is not adversely affected, the ductility of the carburized material at low and intermediate temperatures is very low. During simulated service exposures, the formation of surface corrosion scales, the precipitation of carbides and the formation of internal oxides below the surface leads to depletion of the matrix in the alloying elements involved in the corrosion processes. In thin-walled tubes the depletion of Cr due to Cr2O3 formation on the surface can lead to a loss of creep strength. An additional depletion effect resulting from environmental-metal reactions is the loss of carbon (decarburization) which may occur in specific environments. The compositions of the cooling gases which decarburize the material have been determined; they are to be avoided during reactor operation

  9. An investigation of the treatment of particulate matter from gasoline engine exhaust using non-thermal plasma

    International Nuclear Information System (INIS)

    A plasma reactor with catalysts was used to treat exhaust gas from a gasoline engine in order to decrease particulate matter (PM) emissions. The effect of non-thermal plasma (NTP) of the dielectric discharges on the removal of PM from the exhaust gas was investigated experimentally. The removal efficiency of PM was based on the concentration difference in PM for particle diameters ranging from 0.3 to 5.0 ?m as measured by a particle counter. Several factors affecting PM conversion, including the density of plasma energy, reaction temperature, flow rate of exhaust gas, were investigated in the experiment. The results indicate that PM removal efficiency ranged approximately from 25 to 57% and increased with increasing energy input in the reactor, reaction temperature and residence time of the exhaust gas in the reactor. Enhanced removal of the PM was achieved by filling the discharge gap of the reactor with Cu-ZSM-5 catalyst pellets. In addition, the removal of unburned hydrocarbons was studied. Finally, available approaches for PM conversion were analyzed involving the interactions between discharge and catalytic reactions

  10. 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...

  11. MODIFIED EXHAUST FAN

    Directory of Open Access Journals (Sweden)

    Md. Jahangir Alam

    2014-05-01

    Full Text Available In this paper the increasing heat transfer rate and removing dust and fume from the working space by using our modified exhaust fan have been discussed. By surveying on the customer needs we think about the increasing of heat transfer rate which makes our product more appreciable to the customer. It provides comfort and fresh breathable environment for the user. This modified exhaust fan can be made by various material. We have discussed all the steps and the purpose for modifying the exhaust fan. We have also calculated the economic analysis. So we hope that our product will take a better position in the market competition of the existing product.

  12. MELCOR Model Development of High Temperature Gas-cooled Reactor

    International Nuclear Information System (INIS)

    The High Temperature Gas-cooled Reactor is one of the major challenging issues on the development of licensing technology for HTGR. The safety evaluation tools of HTGR can be developed in two ways - development of new HTGR-specific codes or revision of existing codes. The KINS is considering using existing analytic tools to the extent feasible, with appropriate modifications for the intended purpose. The system-level MELCOR code is traditionally used for LWR safety analysis, which is capable of performing thermal-fluid and accident analysis, including fission-product transport and release. Recently, this code is being modified for the NGNP HTGR by the NRC. In this study, the MELCOR input model for HTGR with Reactor Cavity Cooling System (RCCS) was developed and the steady state performance was analyzed to evaluate the applicability in HTGR. HTGR model with design characteristics of GT-MHR was developed using MELCOR 2.1 code to validate the applicability of MELCOR code to HTGR. In addition, the steady state of GT-MHR was analyzed with the developed model. It was evaluated to predict well the design parameters of GT-MHR. The developed model can be used as the basis for accident analysis of HTGR with further update of packages such as Radio Nuclide (RN) package

  13. 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.

  14. Modelling Of Gas Flow And Heating In Excitation Channel Of Gas Flow Laser For Optimization Of Temperature Field

    Science.gov (United States)

    Plochocki, Zbigniew; Tschernetsov, Oleg

    1990-01-01

    A simple linear mathematical model of gas flow and gas temperature distribution in the excitation channel of cow, gas flow lasers with transverse electrical glow discharge is proposed. We aim to describe, explain and control the temperature distribution in order to minimize the effect of the so called temperature-overheating instability of the discharge. The most essential assumption of the model is: gas flow is one-dimensional and relatively slow. The model is determined by a single partial differential equation for temperature, and relatively simple algebraic equations for the velocity and the density'. Inspection of the model and preliminary numerical calculations show, that, in the channel, there exist two near-electrode maxima of temperature /which is in accordance with experimental observations/. Location and height of these maxima are mainly dependent on a competition between on-electrode cooling and near-electrode heating of the gas. This fact seems to enable us to control the temperature distribution to avoid the temperature-overheating instability of glow discharge in the channel.

  15. Research for automotive exhaust catalysts using synchrotron radiation

    International Nuclear Information System (INIS)

    In promoting research and development of alternative materials and precious metals for more high-performance exhaust gas purification catalyst has become increasingly important in the detailed analysis of the dynamic behavior of the reaction atmosphere. This paper introduces a case study using synchrotron radiation automobile exhaust purification catalyst. (author)

  16. The trapping system for the recirculated gases at different locations of the exhaust gas recirculation (EGR) pipe of a homogeneous charge compression ignition (HCCI) engine

    International Nuclear Information System (INIS)

    Nowadays, in diesel engines, it is typical to recycle exhaust gases (EGR) in order to decrease pollutant emissions. However, few studies report the precisely measured composition of the recycled gases. Indeed, in order to know precisely the composition of the EGR gases, they have to be sampled hot and not diluted, in contrast to the usual practice. Thus, a new system to collect such samples was developed. With this new trapping system, it is possible to measure the concentrations of NOx, CO, CO2, O2, hydrocarbons (HCs) in the range C1–C9, aldehydes, ketones and PAHs. The trapping system and the analytical protocol used are described in this paper

  17. The trapping system for the recirculated gases at different locations of the exhaust gas recirculation (EGR) pipe of a homogeneous charge compression ignition (HCCI) engine

    Science.gov (United States)

    Piperel, A.; Montagne, X.; Dagaut, P.

    2008-10-01

    Nowadays, in diesel engines, it is typical to recycle exhaust gases (EGR) in order to decrease pollutant emissions. However, few studies report the precisely measured composition of the recycled gases. Indeed, in order to know precisely the composition of the EGR gases, they have to be sampled hot and not diluted, in contrast to the usual practice. Thus, a new system to collect such samples was developed. With this new trapping system, it is possible to measure the concentrations of NOx, CO, CO2, O2, hydrocarbons (HCs) in the range C1-C9, aldehydes, ketones and PAHs. The trapping system and the analytical protocol used are described in this paper.

  18. 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.

  19. 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)

  20. Astrophysics: Exhaust inspection

    Science.gov (United States)

    Meier, David L.

    2008-04-01

    What do you see if you peer into the exhaust of a jet engine larger than our Solar System? Only astronomers with the largest radio telescopes can see the full picture - and definitive observations are beginning to filter through.

  1. 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

    2010-12-01

    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 pyrolized 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 is on charring. The resulting EC/OC ratio is reduced by 0–80% in the presence of most of the salts, although some metal salts increase reported EC/OC at low metal to carbon ratios. The results imply that EC/OC ratios of ambient aerosols quantified with TOEGA have variable low biases due to the presence of metals. 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.

  2. EXHAUST EMISSIONS FROM A DIESEL ENGINE

    Science.gov (United States)

    Studies were performed using (1) Diesel particles collected from the undiluted exhaust of a single-cylinder engine, operated at constant speed and load, using a binary pure hydrocarbon fuel with air or gas mixture oxidizers, and (2) Diesel particles collected from the diluted exh...

  3. Application of plasma techniques for exhaust aftertreatment.

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, M.; Viden, I.; Šimek, Milan; Pekárek, S.

    2001-01-01

    Ro?. 27, 1-4 (2001), s. 306-314. ISSN 0143-3369 R&D Projects: GA ?R GA202/99/1298 Institutional research plan: CEZ:AV0Z2043910 Keywords : Non-thermal plasma, elctrical discharge, exhaust aftertreatment Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.190, year: 2001

  4. Simulación del flujo de gas en ductos de escape de motores de combustión interna: Primera parte: aspectos teóricos / Internal combustion engine exhaust pipe flow simulation: Part I: theoretical aspects

    Scientific Electronic Library Online (English)

    Juan Miguel, Mantilla; Camilo Andrés, Falla; Jorge Arturo, Gómez.

    2009-04-01

    Full Text Available La simulación del sistema de escape de un motor de combustión de cuatro tiempos encendido por chispa se puede realizar a partir de la teoría de flujo inestable de gases utilizando ondas de presión. El método aquí explicado se basa en la discretización de espacios interpolables denominados mallas, qu [...] e se ubican a lo largo de toda la tubería sin importar la forma o el tamaño de ésta. Se hace entonces una exploración teórica por los aspectos más importantes, como son el movimiento y choque de las ondas de presión y su aplicación a casos encontrados en ductos de motores reales. Así mismo se plantea la forma en que debe realizarse la simulación utilizando como base la anterior exploración. Los resultados presentados en forma de ecuaciones para esta primera entrega, muestran la gran influencia que ejerce el movimiento de las ondas de presión dentro de un motor sobre el flujo a través del mismo y por ende sobre su desempeño final. Abstract in english Unsteady gas flow theory can be used for simulating a spark ignition internal combustion engine’s exhaust system, using pressure waves. The method explained here is based on the discretization of interpolated spaces (called meshes) which are located throughout the whole length of the exhaust pipe, i [...] rrespective of its form or size. The most important aspects of this theory are theoretically explored, such as pressure wave movement and shock and their application to cases found in real engines’ exhaust pipes. This work also considers how the simulation must be made, based on the previous exploration. The results (presented as equations in this first paper) show the great influence exerted by pressure wave movement on flow through the engine and therefore on its final performance.

  5. 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.

  6. A ROBUST RADIAL TRAVERSE TEMPERATURE PROBE FOR APPLICATION TO A GAS TURBINE HP/IP STAGE

    OpenAIRE

    Wilson, AJW; Ireland, PT; Stevenson, R.; Thorpe, SJ; D. Martin

    2012-01-01

    The requirements to reduce engine fuel burn costs and gaseous emissions combine to ensure that gas turbine engine manufacturers continually seek to increase the peak cycle temperatures of new engine designs. Consequently, high-pressure turbine components must be developed that can withstand increasing gas temperatures, resulting in the continuous introduction of new technologies that allow appropriate service life. Accurate gas path measurements are vital for early understanding of the perfor...

  7. Formation potential of vehicle exhaust nucleation mode particles on-road and in the laboratory

    Science.gov (United States)

    Giechaskiel, Barouch; Ntziachristos, Leonidas; Samaras, Zissis; Scheer, Volker; Casati, Roberto; Vogt, Rainer

    A mobile laboratory equipped with gas analysers, a particle number counter and a scanning mobility particle sizer was employed to measure the exhaust particle size distributions of a diesel Euro III passenger car, chasing its exhaust plume on a high-speed track at 50, 100 and 120 km h -1. Emissions from the same vehicle were also measured in the laboratory under the same driving conditions, using a partial flow sampling system with constant sampling conditions. The vehicle was equipped with an oxidation catalyst and was operated on diesel fuel with 280 ppm wt. sulphur content. Similar results for the exhaust aerosol behaviour were found in both sampling environments, despite the different dilution ratio, sampling temperature and residence time of the aerosol in dilute conditions. A relatively constant soot particle mode was formed in all cases and, in addition, a nucleation mode started to form at 100 km h -1 and became more stable at 120 km h -1. No nucleation mode was observed at 50 km h -1 road load. The similar behaviour of nucleation mode particles both in the chasing and the laboratory tests indicated that such small volatile particles are a true vehicle emission component and not a dilution artefact. Additional measurements in the laboratory with varying engine load revealed that the nucleation mode formation is sensitive to exhaust gas temperature and its occurrence in increased temperature is repeatable and stable for long sampling times. The findings of this study indicate that nucleation mode particles are an actual emission component of diesel passenger cars and they need to be considered in relevant exhaust aerosol characterization studies.

  8. Alternative temperature effect on corrosion resistance of gas turbine blade materials

    International Nuclear Information System (INIS)

    Paper presents the results of sulfide oxide corrosion test of ZhS6K and EN893VD nickel alloys at temperature variation various conditions. One provides recommendations to ensure reduction of the effect of operation conditions of gas turbine plants with varying temperature on corrosion of gas turbine blades. The continuous step-by-step temperature reduction from 800 up to 700oC is found to cause more intensive corrosion in contrast to the similar conditions of temperature increase from 700 up to 800oC. All temperature variation conditions result in more intensive corrosion in contrast to the equivalent constant temperature conditions

  9. 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)

  10. 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 important factor governing the soot reactivity. In the third phase of this research, diesel soot was generated under 0 and 20% EGR using a four-cylinder, four-stroke, turbocharged common rail direct injection (DI) DDC diesel engine. The objective of this work was to examine the relevance of the single cylinder engine and flame studies to practical engine operation. The key engine parameters such as load, speed, and injection timing were kept constant to isolate the EGR effect on soot properties from any other engine effects. The thermokinetic analyses of the flame soot and engine soot showed a significant increase in soot oxidation rate as a result of the CO2 or EGR inclusion into the combustion process. The activation energy of soot oxidation was found to be independent of soot origin or formation history. The increase in soot oxidation rate is attributed solely to the increase in soot active sites, which are presented implicitly in the pre-exponential factor (A) of the oxidation rate equation. This latter statement was confirmed by measuring the initial active site area (ASA i) of all soot samples considered in this study. As expected, higher oxidation rates are associated with higher ASAi. The chemical properties of the soot were investigated to determine their effects upon soot reactivity. The results showed that the H/C and O/C ratios were not modified by CO2 or EGR addition. Therefore, these ratios are not reactivity parameters and their effects upon soot reactivity were ruled out. In distinct contrast, the physical properties of the soot were modified by the addition of CO2 or EGR. The interlayer spacing (d002) between the aromatic sheets increased, the crystallite width (La) decreased and the crystallite height (Lc) decreased as a consequence of CO 2 or EGR addition. The modified physical properties of the soot are responsible for the increased rate of soot oxidation. In order to examine the soot oxidation behavior in the DPF, the soot samples produced from the DDC engine under 0 and 20% EGR were partially oxidized in a thermogravimetric analyzer (TGA) to s

  11. Large-scale time-resolved digital particle image velocimetry (TR-DPIV) for measurement of high subsonic hot coaxial jet exhaust of a gas turbine engine

    Science.gov (United States)

    Timmerman, B. H.; Skeen, A. J.; Bryanston-Cross, P. J.; Graves, M. J.

    2009-07-01

    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 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.

  12. 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 jet flow

  13. Development of high-reliable tungsten-rhenium alloy thermocouple for measuring in-core helium-gas temperature in very high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Composite-type stranded tungsten-rhenium alloy thermocouples have been developed for measuring in-core outlet-gas temperature of 950 0C to 1200 0C in VHTR. Long-term high-temperature out-pile and in-pile tests for these thermocouples and post-irradiation examinations were made. The results showed their reliable and stable performances at temperatures of 1000 0C and 1400 0C

  14. Seismic analysis of the modular high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    This paper reviews the seismic analysis performed for the modular high-temperature gas cooled reactor (MHTGR). The four unit MHTGR nuclear island consists of four separate underground concrete silo structures embedded to a depth of 160 feet. The major NSSS components, including the reactor vessel, and steam generator are housed in the silos. A three-dimensional (3-D) soil-structure interaction (SSI) analysis was performed using the computer program SASSI to develop the seismic loads, acceleration time histories, and response spectra which are to be used in determining the seismic capabilities of the reactor building and its ''safety-related''internal systems and components. The analysed 3-D model included the below grade structures, the reactor and steam generator vessels, the reactor core and other internal structures. A 3-D analysis was performed to take full advantage of embedment in reducing seismic response. The computer program SASSI was selected because it can model 3-D multiple embedded flexible foundations with arbitrary shapes. In the MHTGR design, it is important to model the silo flexibility. The MHTGR is being developed as a standardized plant with a design which envelopes the seismic conditions at 85 percent of U.S. nuclear sites. The maximum Safe Shutdown Earthquake (SSE) acceleration is 0.3g. The paper will review the following subjects: Seismic criteria, and site conditions; Method of analysis; Silo and NSSS models used; Results of the analysis including maximum accelerations and response spectra in the silo and critical equipment supports. The advantages of embedment have been clearly demonstrated in this analysis and will be reviewed in the conclusions of this paper. Furthermore, the results of a separate analysis to assess the effects of silo-soil-silo interaction effects will be discussed. (author). 8 refs, 10 figs, 1 tab

  15. Proliferation resistance assessment of high temperature gas reactors

    International Nuclear Information System (INIS)

    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)

  16. Temperature dependence of gas sensing behaviour of TiO2 doped PANI composite thin films

    International Nuclear Information System (INIS)

    In the present work we have reported the effect of temperature on the gas sensing properties of TiO2 doped PANI composite thin film based chemiresistor type gas sensors for hydrogen gas sensing application. PANI and TiO2 doped PANI composite were synthesized by in situ chemical oxidative polymerization of aniline at low temperature. The electrical properties of these composite thin films were characterized by I-V measurements as function of temperature. The I-V measurement revealed that conductivity of composite thin films increased as the temperature increased. The changes in resistance of the composite thin film sensor were utilized for detection of hydrogen gas. It was observed that at room temperature TiO2 doped PANI composite sensor shows higher response value and showed unstable behavior as the temperature increased. The surface morphology of these composite thin films has also been characterized by scanning electron microscopy (SEM) measurement

  17. Silicon Carbide-Based Hydrogen Gas Sensors for High-Temperature Applications

    Directory of Open Access Journals (Sweden)

    Sangchoel Kim

    2013-10-01

    Full Text Available 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.

  18. BP Neural Network based on PSO Algorithm for Temperature Characteristics of Gas Nanosensor

    OpenAIRE

    Weiguo Zhao

    2012-01-01

    To comprehensively understand the characteristics of gas nanosensor between temperature and sensitivity, this paper has developed a Backward Propagation (BP) neural network based on Particle Swarm Optimization (PSO), which is applied to fitting the temperature-sensitivity characteristic of the SnO2 gas nanosensor mixed with benzene. The simulation results show the PSO can well optimize the structure of the BP network, and the fitting accuracy of the temperature of nanosensor using the acquire...

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

    International Nuclear Information System (INIS)

    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).

  20. 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).

  1. High Temperature Gas-Cooled Reactor Coupled with High Temperature Steam Electrolysis

    International Nuclear Information System (INIS)

    The US Department of Energy is investigating the use of high-temperature gas-cooled reactors (HTGR) to produce electricity and hydrogen. Although the hydrogen production processes using the nuclear energy are in an early stage of development, coupling hydrogen plant to HTGR requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear plant. In anticipation of the design, development and procurement of an advanced power conversion system for HTGR, this study was initiated to identify the major design and technology options and their tradeoffs in the evaluation of power conversion unit (PCU) coupled to the hydrogen plant. In this study, we investigated a number of design configurations and performed thermal hydraulic analyses using various working fluids and various conditions. Also using the high temperature steam electrolysis process (HTSE), we calculated the energy requirement for the operation of the HTSE. The balance of the plant of the HTSE was developed and the HTGR was modeled to be coupled with the HTSE. This paper presents a portion of results obtained from this study. (authors)

  2. Reactor User Interface Technology Development Roadmaps for a High Temperature Gas-Cooled Reactor Outlet Temperature of 750 degrees C

    International Nuclear Information System (INIS)

    This report evaluates the technology readiness of the interface components that are required to transfer high-temperature heat from a High Temperature Gas-Cooled Reactor (HTGR) to selected industrial applications. This report assumes that the HTGR operates at a reactor outlet temperature of 750 C and provides electricity and/or process heat at 700 C to conventional process applications, including the production of hydrogen.

  3. Hot fuel gas cleaning in IGCC at gasification temperature

    Energy Technology Data Exchange (ETDEWEB)

    Michael Mueller; Domenico Pavone; Michael Rieger; Ralf Abraham [Forschungszentrum Juelich GmbH (Germany)

    2009-07-01

    A hot gas cleaning above the ash melting point has already been successfully demonstrated for PPCC. This paper gives two examples how this type of hot gas cleaning could be integrated and improved in an IGCC with CO{sub 2} removal. The main advantage is the avoidance of slagging and fouling problems without the need for a gas quench. This is the prerequisite for the trouble-free operation of a high efficient heat exchanger, a turbine, and a catalytic membrane, which offer the possibility of a significant increase in efficiency. First estimations show that a hot gas cleaning above the melting point should work under gasification conditions, too. It should be possible to sufficiently clean the hot fuel gas from particles and alkalies avoiding slagging and fouling. However, maybe further hot gas cleaning, e.g. hot desulphurisation, is necessary depending on the type of catalytic membrane. Research on the hot gas cleaning itself is needed. The corrosion resistance of available ceramics for liquid slag removal has to be tested under gasification conditions or new ceramics have to be developed. Also the alkali sorbents have to be tested under gasification conditions or new sorbents have to be developed, if needed. The complete hot gas cleaning has to be tested step by step under relevant conditions. In the cases described research on catalytic membranes is needed. The sensitivity of potential materials against major and minor gas components has to be investigated to define the requirements on the cleanliness of the gas and thus demands on a sufficient hot gas cleaning. However, suitable catalytic membranes must first be developed. All other parts of the considered IGCCs need further research, development or at least improvement to develop an advanced coal-based IGCC. 3 refs., 5 figs.

  4. 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.

  5. Study of the infrared emission spectrum of combustion gases: application to the measurement of gas temperature and CO{sub 2} concentration; Etude du spectre d'emission infrarouge des gaz de combustion: application a la mesure de temperature de gaz et de concentration de CO2

    Energy Technology Data Exchange (ETDEWEB)

    Vally, J.

    1999-07-01

    This work deals with the problem of determination of gases temperature by non-intrusive methods. Measurement methods are developed which are based on the study of the infrared emission spectrum of the gas. Two types of application are considered: the determination of the temperature profile inside an exhaust gas (low temperature, atmospheric pressure) and the determination of the temperature inside the combustion chamber of a gas turbine (high temperature, high pressure). The temperature profiles in exhaust gases are obtained from the measurement of the CO{sub 2} emission spectrum between 2380 and 2400 nm. This spectral domain has been chosen because of its high sensibility with respect to temperature profile evolutions. From the modeling of the spectrum in this domain, the sensibility of the luminance measurement with respect to the evolution of temperature is quantified. The behaviour of the nuclei of the radiant heat transfer equation has permitted to determine the weight of each gas layer in the spectrum measurement. This study of the direct problem allows to define a convenient inversion method based on the minimization by non-linear optimization of a quadratic criterion. The impact of the measurement noise on the inverse parameters has been analyzed by a Monte-Carlo method. These studies have permitted to define a measurement method and the characteristics of a sensor. An apparatus based on these characteristics has been developed. Measurements were performed on a turbojet engine at the Defense Research Agency (DERA) and were compared to the intrusive measurements performed in parallel by DERA. The difference between the temperature profiles obtained with both measurement systems (optical and intrusive) are of about few percent. (J.S.)

  6. Tangential seals for a gas-cooled high temperature reactor

    International Nuclear Information System (INIS)

    The tangential seal is situated above the reactor core and separates the hot gas space from the cold gas space. It consists of seals which are moved by a combination of screws and tensioning elements if thermal differential expansion occurs. Each seal is made as a cantilever. The whole tangential seal can glide along the chamfered surface of the side reflector. (DG)

  7. 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)

  8. The Cluster Gas Mass - Temperature Relation Evidence for a High Level of Preheating

    CERN Document Server

    McCarthy, I G; Balogh, M L; Carthy, Ian G. Mc; Babul, Arif; Balogh, Michael L.

    2002-01-01

    Recent X-ray observations have been used to demonstrate that the cluster gas mass - temperature relation is steeper than theoretical self-similar predictions drawn from numerical simulations that consider the evolution of the cluster gas through the effects of gravity and shock heating alone. One possible explanation for this is that the gas mass fraction is not constant across clusters of different temperature, as usually assumed. Observationally, however, there is no compelling evidence for gas mass fraction variation, especially in the case of hot clusters. Seeking an alternative physical explanation for the observed trends, we investigate the role of preheating the intracluster medium by some arbitrary source on the cluster gas mass - temperature relation for clusters with emission-weighted mean temperatures of greater than about 3 keV. Making use of the physically-motivated, analytic model developed by Babul et al. (2002), we find that preheating does, indeed, lead to a steeper relation. This is in agree...

  9. Parallel temperatures in supersonic beams: Ultracooling of light atoms seeded in a heavier carrier gas

    International Nuclear Information System (INIS)

    Supersonic expansion is a very powerful tool to produce an atomic beam with a well defined velocity and, by seeding a test gas in such an expansion, the energy of the test gas can be transferred, at least partially, to the very-low-temperature carrier gas. The case usually studied is the one of a heavy gas seeded in a light carrier gas and, in this case, the parallel temperature of the seeded gas is always larger than the one of the carrier gas. In the present paper, we study the opposite case which has received less attention: when a light gas is seeded in a heavier carrier gas, the parallel temperature can be substantially lower for the seeded gas than for the carrier gas. This effect has been first observed by Campargue and co-workers in 2000, in the case of atomic oxygen seeded in argon. In the present paper, we develop a theoretical analysis of this effect, in the high dilution limit, and we compare our theoretical results to several experimental observations, including a set of measurements we have made on a beam of lithium seeded in argon. The agreement between theory and experiments is good

  10. Predicted nuclear heating and temperatures in gas-cooled nuclear reactors for process heat applications

    International Nuclear Information System (INIS)

    The high-temperature gas-cooled nuclear reactor (HTGR) is an attractive potential source of primary energy for many industrial and chemical process applications. Significant modification of current HTGR core design will be required to achieve the required elevations in exit gas temperatures without exceeding the maximum allowable temperature limits for the fuel material. A preliminary evaluation of the effects of various proposed design modifications by predicting the resulting fuel and gas temperatures with computer calculational modeling techniques is reported. The design modifications evaluated are generally those proposed by the General Atomic Company (GAC), a manufacturer of HTGRs, and some developed at the LASL. The GAC modifications do result in predicted fuel and exit gas temperatures which meet the proposed design objectives

  11. 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)

  12. 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 failure mechanisms; accident testing; fuel and fission product chemistry; fuel cycles; fission product transport; spent fuel management; and nuclear hydrogen production. This knowledge base was gained over nearly fifty years of fuel materials research and development in the international HTGR community. The primary intent of this effort is that this documented experience will provide the basis for further development of HTGR fuels and reactor systems. In many ways this book is a unique source of past experience, and hopefully, it will serve as an important part of future development of nuclear energy worldwide for the new generation scientists and engineers

  13. Waste heat recovery from the exhaust of a diesel generator using Rankine Cycle

    International Nuclear Information System (INIS)

    Highlights: • Diesel engine exhaust contains 40% energy which can be used to produce extra power. • Extra 11% power gained with optimized heat exchangers using water as working fluid. • As a result brake specific fuel consumption improved by 12%. • Parallel arrangement of heat exchangers showed better performance than series. • Optimum working fluid pressure varies with the engine power. - Abstract: Exhaust heat from diesel engines can be an important heat source to provide additional power using a separate Rankine Cycle (RC). In this research, experiments were conducted to measure the available exhaust heat from a 40 kW diesel generator using two ‘off-the-shelf’ heat exchangers. The effectiveness of the heat exchangers using water as the working fluid was found to be 0.44 which seems to be lower than a standard one. This lower performance of the existing heat exchangers indicates the necessity of optimization of the design of the heat exchangers for this particular application. With the available experimental data, computer simulations were carried out to optimize the design of the heat exchangers. Two heat exchangers were used to generate super-heated steam to expand in the turbine using two orientations: series and parallel. The optimized heat exchangers were then used to estimate additional power considering actual turbine isentropic efficiency. The proposed heat exchanger was able to produce 11% additional power using water as the working fluid at a pressure of 15 bar at rated engine load. This additional power resulted into 12% improvement in brake-specific fuel consumption (bsfc). The effects of the working fluid pressure were also investigated to maximize the additional power production. The pressure was limited to 15 bar which was constrained by the exhaust gas temperature. However, higher pressure is possible for higher exhaust gas temperatures from higher capacity engines. This would yield more additional power with further improvements in bsfc. At 40% part load, the additional power developed was 3.4% which resulted in 3.3% reduction in bsfc

  14. Analysis Of A High Temperature Gas-Cooled Reactor Powered High Temperature Electrolysis Hydrogen Plant

    International Nuclear Information System (INIS)

    An updated reference design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The reactor heat is used to produce heat and electric power to the HTE plant. A Rankine steam cycle with a power conversion efficiency of 44.4% was used to provide the electric power. The electrolysis unit used to produce hydrogen includes 1.1 million cells with a per-cell active area of 225 cm2. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 42.8% at a hydrogen production rate of 1.85 kg/s (66 million SCFD) and an oxygen production rate of 14.6 kg/s (33 million SCFD). An economic analysis of this plant was performed with realistic financial and cost estimating The results of the economic analysis demonstrated that the HTE hydrogen production plant dd that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a competitive cost. A cost of $3.03/kg of hydrogen was calculated assuming an internal rate of return of 10% and a debt to equity ratio of 80%/20% for a reactor cost of $2000/kWt and $2.41/kg of hydrogen for a reactor cost of $1400/kWt.

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

    International Nuclear Information System (INIS)

    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.

  16. Ethanol, acetone and ammonia gas room temperature operated sensor

    Science.gov (United States)

    Singh, Iqbal; Bedi, R. K.

    2013-06-01

    CuO nanocrystalline thick films were fabricated from powder synthesized by a sol-gel auto combustion route at different pH value of the precursor solution. The gas sensing response of thick film samples towards ethanol, acetone and ammonia gases has been tested and response has been found to be higher for ammonia gas. The sensor recovers its original state after ammonia exposure.

  17. Qualitative gas temperature distribution in positive DC glow corona using spectral image processing in atmospheric air

    Science.gov (United States)

    Matsumoto, Takao; Inada, Yoichi; Shimizu, Daisuke; Izawa, Yasuji; Nishijima, Kiyoto

    2015-01-01

    An experimental method of determining a qualitative two-dimensional image of the gas temperature in stationary atmospheric nonthermal plasma by spectral image processing was presented. In the experiment, a steady-state glow corona discharge was generated by applying a positive DC voltage to a rod-plane electrode in synthetic air. The changes in the gas temperature distribution due to the amplitude of applied voltage and the ambient gas pressure were investigated. Spectral images of a positive DC glow corona were taken using a gated ICCD camera with ultranarrow band-pass filters, corresponding to the head and tail of a N2 second positive system band (0–2). The qualitative gas temperature was obtained from the emission intensity ratio between the head and tail of the N2 second positive system band (0–2). From the results, we confirmed that the gas temperature and its distribution of a positive DC glow corona increased with increasing applied voltage. In particular, just before the sparkover voltage, a distinctly high temperature region was formed in the positive DC glow at the tip of the rod electrode. In addition, the gas temperature decreased and its distribution spread diffusely with decreasing ambient gas pressure.

  18. Gas temperature determination from rotational lines in non-equilibrium plasmas: a review

    International Nuclear Information System (INIS)

    The gas temperature in non-equilibrium plasmas is often obtained from the plasma-induced emission by measuring the rotational temperature of a diatomic molecule in its excited state. This is motivated by both tradition and the availability of low budget spectrometers. However, non-thermal plasmas do not automatically guarantee that the rotational distribution in the monitored vibrational level of the diatomic molecule is in equilibrium with the translational (gas) temperature. Often non-Boltzmann rotational molecular spectra are found in non-equilibrium plasmas. The deduction of a gas temperature from these non-thermal distributions must be done with care as clearly the equilibrium between translational and rotational degrees of freedom cannot be achieved. In this contribution different methods and approaches to determine the gas temperature are evaluated and discussed. A detailed analysis of the gas temperature determination from rotational spectra is performed. The physical and chemical background of non-equilibrium rotational population distributions in molecular spectra is discussed and a large range of conditions for which non-equilibrium occurs are identified. Fitting procedures which are used to fit (non-equilibrium) rotational distributions are analyzed in detail. Lastly, recommendations concerning the conditions for which the gas temperatures can be obtained from diatomic spectra are formulated. (invited review)

  19. Multi-spectral pyrometer for gas turbine blade temperature measurement

    Science.gov (United States)

    Gao, Shan; Wang, Lixin; Feng, Chi

    2014-09-01

    To achieve the highest possible turbine inlet temperature requires to accurately measuring the turbine blade temperature. If the temperature of blade frequent beyond the design limits, it will seriously reduce the service life. The problem for the accuracy of the temperature measurement includes the value of the target surface emissivity is unknown and the emissivity model is variability and the thermal radiation of the high temperature environment. In this paper, the multi-spectral pyrometer is designed provided mainly for range 500-1000°, and present a model corrected in terms of the error due to the reflected radiation only base on the turbine geometry and the physical properties of the material. Under different working conditions, the method can reduce the measurement error from the reflect radiation of vanes, make measurement closer to the actual temperature of the blade and calculating the corresponding model through genetic algorithm. The experiment shows that this method has higher accuracy measurements.

  20. 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.

  1. Resonance hadron gas and QCD nonperturbative vacuum at a finite temperature

    International Nuclear Information System (INIS)

    The non-perturbative QCD vacuum with two light quarks at the finite temperature is studied within the frames of the hadron resonance gas model. The temperature dependences of the quark and gluon condensates in the confinement phase are obtained. It is shown that the quark condensate and half the gluon condensate (the chromoelectrical component) are evaporated by one temperature corresponding to the temperature Tc ? 100 MeV

  2. Gas temperature in the cathode region of a dc glow discharge with a thermionic cathode

    International Nuclear Information System (INIS)

    The gas temperature in the cathode region of a low pressure dc He-Xe glow discharge in spot mode is determined from the Doppler broadened line profile of the xenon 1s5-2p6 transition (823.16 nm), which is obtained by means of a laser atom absorption spectroscopy. The inhomogeneous temperature distribution in the radial direction has to be taken into consideration. In order to model the gas temperature distribution the heat balance equation is solved. The comparison of the experimental and theoretical temperature profiles shows good agreement

  3. Sub-to super-ambient temperature programmable microfabricated gas chromatography column

    Science.gov (United States)

    Robinson, Alex L.; Anderson, Lawrence F.

    2004-03-16

    A sub- to super-ambient temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by combining a thermoelectric cooler and temperature sensing on the microfabricated column. Sub-ambient temperature programming enables the efficient separation of volatile organic compounds and super-ambient temperature programming enables the elution of less volatile analytes within a reasonable time. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  4. Integrated exhaust scenarios with actively controlled ELMs

    International Nuclear Information System (INIS)

    An integrated high performance scenario based on simultaneous feedback control of the averaged divertor neutral particle and power flux has been established at ASDEX Upgrade. This approach is fully compatible with the present tungsten wall coating covering about 65% of the plasma facing components and intended for application in the envisaged full-tungsten experiment. In our experiments, particle exhaust and divertor temperature derived from thermoelectric currents were tuned by acting on gas puff and argon injection rates. The ELM frequency is controlled by repetitive injection of small cryogenic deuterium pellets to avoid radiative instabilities occurring at low fELM and high radiated power and to control the ELM energy. No confinement loss is observed in this radiative type-I ELMy scenario with relatively flat density profiles. In contrast, similar type-III ELM scenarios achieved in hydrogen shows a relative confinement loss of 20% as compared to the type-I phase. In parallel to pellets, alternative ELM trigger techniques like fast vertical plasma oscillations were developed and investigated as well. A particular experimental challenge for AUG conditions is to obtain a high pace making frequency. (author)

  5. Vehicle exhaust treatment using electrical discharge and materials chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Tonkyn, R.G.; Balmer, M.L.; Barlow, S.E.; Orlando, T.M. [Pacific Northwest National Lab., Richland, WA (United States); Goulette, D.; Hoard, J. [Ford Motor Co., Dearborn, MI (United States). Scientific Research Lab.

    1997-12-31

    Current 3-way catalytic converters have proven quite effective at removing NO{sub x} from the exhaust of spark ignition vehicles operating near stoichiometric air-to-fuel ratios. However, diesel engines typically operate at very high air-to-fuel ratios. Under such lean burn conditions current catalytic converters are ineffective for NO{sub x} removal. As a result, considerable effort has been made to develop a viable lean NO{sub x} catalyst. Although some materials have been shown to reduce NO{sub x} under lean burn conditions, none exhibit the necessary activity and stability at the high temperatures and humidities found in typical engine exhaust,. As a result, alternative technologies are being explored in an effort to solve the so-called lean NO{sub x} problem. Packed-bed barrier discharge systems are well suited to take advantage of plasma-surface interactions due to the large number of contaminant surface collisions in the bed. The close proximity of the active surface to transient species produced by the plasma may lead to favorable chemistry at considerably lower temperatures than required by thermal catalysts. The authors present data in this paper illustrating that the identity and surface properties of the packing material can alter the discharge-driven chemistry in synthetic leanburn exhaust mixtures. Results using non-porous glass beads as the packing material suggest the limits of NO{sub x} reduction using purely gas phase discharge chemistry. By comparison, encouraging results are reported for several alternative packing materials.

  6. Experimental transient turbine blade temperatures in a research engine for gas stream temperatures cycling between 1067 and 1567 k

    Science.gov (United States)

    Gauntner, D. J.; Yeh, F. C.

    1975-01-01

    Experimental transient turbine blade temperatures were obtained from tests conducted on air-cooled blades in a research turbojet engine, cycling between cruise and idle conditions. Transient data were recorded by a high speed data acquisition system. Temperatures at the same phase of each transient cycle were repeatable between cycles to within 3.9 K (7 F). Turbine inlet pressures were repeatable between cycles to within 0.32 N/sq cm (0.47 psia). The tests were conducted at a gas stream temperature of 1567 K (2360 F) at cruise, and 1067 K (1460 F) at idle conditions. The corresponding gas stream pressures were about 26.2 and 22.4 N/sq cm (38 and 32.5 psia) respectively. The nominal coolant inlet temperature was about 811 K (1000 F).

  7. A compilation of the solutions to the important equations in low-temperature gas atom diffusion

    International Nuclear Information System (INIS)

    This paper collects together the solutions for the diffusion of unstable gas atoms within a semi-infinite solid. Allowance is made for one precursor. These solutions are appropriate to the diffusion of unstable gas atoms from inside the fuel into the pin voidage in situations where the radius of curvature of the surface can be neglected. The solutions are particularly relevant to low-temperature gas atom diffusion and are thus of considerable value to coolant analysis at commercial AGR stations. (orig.)

  8. Effect of temperature variation and gas composition on the stability of the RPC operation

    International Nuclear Information System (INIS)

    An Inverted Double Gap Resistive Plate Chambers (RPC) made of bakelite of 5x109 ?cm volume resistivity was tested at avalanche rates up to 1 kHz/cm2/gap in the Gamma Irradiation Facility at CERN in 2001. The inner surfaces of the chamber electrodes were cladded using linseed oil varnish. Dependence of the intrinsic RPC noise and the stability of the gas gain on the gas temperature and the gas composition are discussed

  9. Effect of Temperature Variation and Gas Composition on the Stability of the RPC Operation

    CERN Document Server

    Cwiok, M; Górski, M; Królikowski, J

    2002-01-01

    An Inverted Double Gap RPC made of bakelite of 5*10^9 Ohm*cm volume resistivity was tested at avalanche rates up to 1 kHz/cm^2/gap in the Gamma Irradiation Facility at CERN in 2001. The inner surfaces of the chamber electrodes were cladded using linseed oil varnish. Dependence of the intrinsic RPC noise and the stability of the gas gain on the gas temperature and the gas composition are discussed.

  10. Effect of temperature variation and gas composition on the stability of the RPC operation

    Science.gov (United States)

    ?wiok, M.; Dominik, W.; Górski, M.; Królikowski, J.

    2003-08-01

    An Inverted Double Gap Resistive Plate Chambers (RPC) made of bakelite of 5×10 9 ?cm volume resistivity was tested at avalanche rates up to 1 kHz/cm2/ gap in the Gamma Irradiation Facility at CERN in 2001. The inner surfaces of the chamber electrodes were cladded using linseed oil varnish. Dependence of the intrinsic RPC noise and the stability of the gas gain on the gas temperature and the gas composition are discussed.

  11. Effect of temperature variation and gas composition on the stability of the RPC operation

    Energy Technology Data Exchange (ETDEWEB)

    Cwiok, M. E-mail: cwiok@fuw.edu.pl; Dominik, W.; Gorski, M.; Krolikowski, J

    2003-08-01

    An Inverted Double Gap Resistive Plate Chambers (RPC) made of bakelite of 5x10{sup 9} {omega}cm volume resistivity was tested at avalanche rates up to 1 kHz/cm{sup 2}/gap in the Gamma Irradiation Facility at CERN in 2001. The inner surfaces of the chamber electrodes were cladded using linseed oil varnish. Dependence of the intrinsic RPC noise and the stability of the gas gain on the gas temperature and the gas composition are discussed.

  12. Hyperventilation and exhaustion syndrome.

    Science.gov (United States)

    Ristiniemi, Heli; Perski, Aleksander; Lyskov, Eugene; Emtner, Margareta

    2014-12-01

    Chronic stress is among the most common diagnoses in Sweden, most commonly in the form of exhaustion syndrome (ICD-10 classification - F43.8). The majority of patients with this syndrome also have disturbed breathing (hyperventilation). The aim of this study was to investigate the association between hyperventilation and exhaustion syndrome. Thirty patients with exhaustion syndrome and 14 healthy subjects were evaluated with the Nijmegen Symptom Questionnaire (NQ). The participants completed questionnaires about exhaustion, mental state, sleep disturbance, pain and quality of life. The evaluation was repeated 4 weeks later, after half of the patients and healthy subjects had engaged in a therapy method called 'Grounding', a physical exercise inspired by African dance. The patients reported significantly higher levels of hyperventilation as compared to the healthy subjects. All patients' average score on NQ was 26.57 ± 10.98, while that of the healthy subjects was 15.14 ± 7.89 (t = -3.48, df = 42, p Burnout Measure SMBM r = 0.565, p syndrome patients and that it can be reduced by systematic physical therapy such as Grounding. PMID:24134551

  13. Silicon Carbide-Based Hydrogen Gas Sensors for High-Temperature Applications

    OpenAIRE

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

    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 ...

  14. Evaluation of the Gas Turbine Inlet Temperature with Relation to the Excess Air

    OpenAIRE

    Rueda Marti?nez, F.; Rueda Marti?nez, A.; Toledo Velazquez, M.; Quinto Diez, P.; Tolentino Eslava, G.; Abugaber Francis, J.

    2011-01-01

    This paper shows the effect of excess air on combustion gas temperature at turbine inlet, and how it determines power and thermal efficiency of a gas turbine at different pressure ratios and excess air. In such a way an analytic Equation that allows calculating the turbine inlet temperature as a function of excess air, pressure ratio and relative humidity is given. Humidity Impact on excess air calculation is also analyzed and presented. Likewise it is demonstrated that dry air calculations d...

  15. Effect of Ambient Temperature on the Performance of Gas Turbines Power Plant

    OpenAIRE

    Naeim Farouk Mohammed; Liu. Sheng; Qaisar Hayat

    2013-01-01

    Efficiency and electric-power output of gas turbines vary according to the ambient conditions. The amount of these variations greatly affects electricity production, fuel consumption and plant incomes. The purpose of the present study is to investigate the effect of the ambient temperature on the performance of gas turbines. We observed that the power decreases due to reduction in air mass flow rate (the density of the air declines as temperature increases) and the efficiency decreases becaus...

  16. MAPPING OF TEMPERATURE AND VELOCITY FIELD IN HOT GAS FREE JET.

    Czech Academy of Sciences Publication Activity Database

    Gregor, Jan; Jakubová, I.; Mendl, T.; Šenk, J.

    Brno, 2005, s. 81-83. ISBN 80-214-2931-3. [Symposium on Physics of Switching Arc /16th./. Nové M?sto na Morav? (CZ), 05.09.2005-09.09.2005] Institutional research plan: CEZ:AV0Z20430508 Keywords : hot gas mixture * temperature * velocity Subject RIV: BL - Plasma and Gas Discharge Physics

  17. Articulated Multimedia Physics, Lesson 14, Gases, The Gas Laws, and Absolute Temperature.

    Science.gov (United States)

    New York Inst. of Tech., Old Westbury.

    As the fourteenth lesson of the Articulated Multimedia Physics Course, instructional materials are presented in this study guide with relation to gases, gas laws, and absolute temperature. The topics are concerned with the kinetic theory of gases, thermometric scales, Charles' law, ideal gases, Boyle's law, absolute zero, and gas pressures. The…

  18. Propagation of light through ship exhaust plumes

    Science.gov (United States)

    van Iersel, M.; Mack, A.; van Eijk, A. M. J.; Schleijpen, H. M. A.

    2014-10-01

    Looking through the atmosphere, it is sometimes difficult to see the details of an object. Effects like scintillation and blur are the cause of these difficulties. Exhaust plumes of e.g. a ship can cause extreme scintillation and blur, making it even harder to see the details of what lies behind the plume. Exhaust plumes come in different shapes, sizes, and opaqueness and depending on atmospheric parameters like wind speed and direction, as well as engine settings (power, gas or diesel, etc.). A CFD model is used to determine the plume's flow field outside the stack on the basis of exhaust flow properties, the interaction with the superstructure of the ship, the meteorological conditions and the interaction of ship's motion and atmospheric wind fields. A modified version of the NIRATAM code performs the gas radiation calculations and provides the radiant intensity of the (hot) exhaust gases and the transmission of the atmosphere around the plume is modeled with MODTRAN. This allows assessing the irradiance of a sensor positioned at some distance from the ship and its plume, as function of the conditions that influence the spatial distribution and thermal properties of the plume. Furthermore, an assessment can be made of the probability of detecting objects behind the plume. This plume module will be incorporated in the TNO EOSTAR-model, which provides estimates of detection range and image quality of EO-sensors under varying meteorological conditions.

  19. Gas sensing properties of nanocrystalline diamond at room temperature.

    Czech Academy of Sciences Publication Activity Database

    Davydova, Marina; Kulha, P.; Laposa, A.; Hruška, Karel; Demo, Pavel; Kromka, Alexander

    2014-01-01

    Ro?. 5, Dec (2014), s. 2339-2345. ISSN 2190-4286 R&D Projects: GA ?R(CZ) GP14-06054P Institutional support: RVO:68378271 Keywords : gas sensor * integrator * interdigitated electrodes * nanocrystalline diamond * response Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.326, year: 2013

  20. Effect of Gas/Steam Turbine Inlet Temperatures on Combined Cycle Having Air Transpiration Cooled Gas Turbine

    Science.gov (United States)

    Kumar, S.; Singh, O.

    2012-10-01

    Worldwide efforts are being made for further improving the gas/steam combined cycle performance by having better blade cooling technology in topping cycle and enhanced heat recovery in bottoming cycle. The scope of improvement is possible through turbines having higher turbine inlet temperatures (TITs) of both gas turbine and steam turbine. Literature review shows that a combined cycle with transpiration cooled gas turbine has not been analyzed with varying gas/steam TITs. In view of above the present study has been undertaken for thermodynamic study of gas/steam combined cycle with respect to variation in TIT in both topping and bottoming cycles, for air transpiration cooled gas turbine. The performance of combined cycle with dual pressure heat recovery steam generator has been evaluated for different cycle pressure ratios (CPRs) varying from 11 to 23 and the selection diagrams presented for TIT varying from 1,600 to 1,900 K. Both the cycle efficiency and specific work increase with TIT for each pressure ratio. For each TIT there exists an optimum pressure ratio for cycle efficiency and specific work. For the CPR of 23 the best cycle performance is seen at a TIT of 1,900 K for maximum steam temperature of 570 °C, which gives the cycle efficiency of 60.9 % with net specific work of 909 kJ/kg.

  1. Analysis of vehicle exhaust waste heat recovery potential using a Rankine cycle

    International Nuclear Information System (INIS)

    This study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis dynamometer. The thermodynamic analysis was performed for water, R123 and R245fa and revealed the advantage of using water as the working fluid in applications of thermal recovery from exhaust gases of vehicles equipped with a spark-ignition engine. Moreover, the heat exchanger effectiveness for the organic working fluids R123 and R245fa is higher than that for the water and, consequently, they can also be considered appropriate for use in vehicle WHR applications through RCs when the exhaust gas temperatures are relatively low. For an ideal heat exchanger, the simulations revealed increases in the internal combustion engine thermal and vehicle mechanical efficiencies of 1.4%–3.52% and 10.16%–15.95%, respectively, while for a shell and tube heat exchanger, the simulations showed an increase of 0.85%–1.2% in the thermal efficiency and an increase of 2.64%–6.96% in the mechanical efficiency for an evaporating pressure of 2 MPa. The results confirm the advantages of using the thermal energy contained in the vehicle exhaust gases through RCs. Furthermore, the present analysis demonstrates that improved evaporator designs and appropriate expander devices allowing for higher evaporating pressures are required to obtain the maximum WHR potential from vehicle RC systems. -- Highlights: ? This study evaluates the vehicle exhaust waste heat recovery potential using Rankine cycle systems. ? A thermodynamic model and a heat exchanger model were developed. ? Experimental data obtained in a vehicle tested on a chassis dynamometer was used as models input. ? Thermodynamic analysis was performed for water, R123 and R245fa. ? Results confirm advantages of using the thermal energy contained in the vehicle exhaust gases through Rankine cycle systems.

  2. Development of a coolant channel helium and nitrogen gas ratio sensor for a high temperature gas reactor

    International Nuclear Information System (INIS)

    To measure the changing gas composition of the coolant during a postulated High Temperature Gas Reactor (HTGR) accident, an instrument is needed. This instrument must be compact enough to measure the ratio of the coolant versus the break gas in an individual coolant channel. This instrument must minimally impact the fluid flow and provide for non-direct signal routing to allow minimal disturbance to adjacent channels. The instrument must have a flexible geometry to allow for the measurement of larger volumes such as in the upper or lower plenum of a HTGR. The instrument must be capable of accurately functioning through the full operating temperature and pressure of a HTGR. This instrument is not commercially available, but a literature survey has shown that building off of the present work on Capacitance Sensors and Cross-Capacitors will provide a basis for the development of the desired instrument. One difficulty in developing and instrument to operate at HTGR temperatures is acquiring an electrical conductor that will not melt at 1600 deg. C. This requirement limits the material selection to high temperature ceramics, graphite, and exotic metals. An additional concern for the instrument is properly accounting for the thermal expansion of both the sensing components and the gas being measured. This work covers the basic instrument overview with a thorough discussion of the associated uncertainty in making these measurements. (authors)(authors)

  3. Models for Toxic Exhausts Handling

    International Science & Technology Center (ISTC)

    Mathematical Modeling of Processes of Formation and Neutralisation of Toxic Exhausts (Development of Methods and Devices for Neutralisation of Exhausts of Toxic in Thermoenergy Devices and Stands for Rocket Engine Test Runs)

  4. The Gas Temperature of Starless Cores in Perseus

    OpenAIRE

    Schnee, Scott; Rosolowsky, Erik; Foster, Jonathan; Enoch, Melissa; Sargent, Anneila

    2008-01-01

    In this paper we study the determinants of starless core temperatures in the Perseus molecular cloud. We use NH3 (1,1) and (2,2) observations to derive core temperatures (T_kin) and data from the COMPLETE Survey of Star Forming Regions and the c2d Spitzer Legacy Survey for observations of the other core and molecular cloud properties. The kinetic temperature distribution probed by NH3 is in the fairly narrow range of 9 - 15 K. We find that cores within the clusters IC348 and...

  5. Liquid/Gas Vortex Separator

    Science.gov (United States)

    Morris, B. G.

    1986-01-01

    Liquid/gas separator vents gas from tank of liquid that contains gas randomly distributed in bubbles. Centrifugal force separates liquid and gas, forcing liquid out of vortex tube through venturi tube. Gas vented through exhaust port. When liquid detected in vent tube, exhaust port closed, and liquid/gas mixture in vent tube drawn back into tank through venturi.

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

    Directory of Open Access Journals (Sweden)

    Jafarmadara S.

    2013-01-01

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

  7. 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.

  8. Boltzmann Temperature in out-of-equilibrium lattice gas

    OpenAIRE

    Oliveira, Mario J.; Petri, Alberto

    2005-01-01

    We investigate the quench of Ising and Potts models via Monte Carlo dynamics, and find that the distribution of the site-site interaction energy has the same form as in the equilibrium case. This form directly derives from the Boltzmann statistics and allows to measure the instantaneous temperature during the systems relaxation. We find that, after an undercritical quench, the system equilibrates in a finite time at the heatbath temperature, while the energy still decreases ...

  9. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Science.gov (United States)

    2010-07-01

    ...Methanol-fueled Otto-cycle vehicles may...not exceeded); or (iii) Using smooth wall duct...exchanger is required. (iii) If a heat exchanger is used...petroleum gas-fueled Otto-cycle and petroleum-fueled...cm) in diameter. (iii) Constructed of...

  10. 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 temperature with equal and small risk of corrosion, but with increased efficiency of the plant

  11. Program for aerodynamic performance tests of helium gas compressor model of the gas turbine high temperature reactor (GTHTR300)

    International Nuclear Information System (INIS)

    Research and development program for helium gas compressor aerodynamics was planned for the power conversion system of the Gas Turbine High Temperature Reactor (GTHTR300). The axial compressor with polytropic efficiency of 90% and surge margin more than 30% was designed with 3-dimensional aerodynamic design. Performance and surge margin of the helium gas compressor tends to be lower due to the higher boss ratio which makes the tip clearance wide relative to the blade height, as well as due to a larger number of stages. The compressor was designed on the basis of methods and data for the aerodynamic design of industrial open-cycle gas-turbine. To validate the design of the helium gas compressor of the GTHTR300, aerodynamic performance tests were planned, and a 1/3-scale, 4-stage compressor model was designed. In the tests, the performance data of the helium gas compressor model will be acquired by using helium gas as a working fluid. The maximum design pressure at the model inlet is 0.88 MPa, which allows the Reynolds number to be sufficiently high. The present study is entrusted from the Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

  12. Calculation of UF sub 6 gas density, temperature, pressure, and Mach number changes across a normal shock in a gas-centrifuge environment

    Science.gov (United States)

    Gentry, R. A.

    1983-03-01

    The nonlinear Rankine-Hugoniot equations are solved to obtain changes in UF6 gas density, temperature, pressure, and Mach number across a normal shock in a gas centrifuge environment. Effects of the nonlinear temperature variation of the enthalpy and specific heats of UF6 are included to insure that realistic predictions of gas temperature and pressure are obtained. Tables of values of gas density, temperature, pressure, and Mach number describing conditions behind a normal shock are presented as functions of the upstream Mach number and the upstream gas temperature. Values of the gas stagnation temperature and stagnation pressure are also included. The tables give tabular results corresponding to centrifuge wall speeds ranging from 350 m/s to 1100 m/s.

  13. Calculation of UF6 gas density, temperature, pressure, and Mach number changes across a normal shock in a gas-centrifuge environment

    International Nuclear Information System (INIS)

    The nonlinear Rankine-Hugoniot equations are solved to obtain changes in UF6 gas density, temperature, pressure, and Mach number across a normal shock in a gas-centrifuge environment. Effects of the nonlinear temperature variation of the enthalpy and specific heats of UF6 are included to insure that realistic predictions of gas temperature and pressure are obtained. Tables of values of gas density, temperature, pressure, and Mach number describing conditions behind a normal shock are presented as functions of the upstream Mach number and the upstream gas temperature. Values of the gas stagnation temperature and stagnation pressure are also included. The tables give tabular results corresponding to centrifuge wall speeds ranging from 350 m/s to 1100 m/s

  14. Mathematical model of the automatic control of temperature modes of gas-field wells

    Directory of Open Access Journals (Sweden)

    Kozhakin Vladimir Vasilyevich

    2011-02-01

    Full Text Available A double circuit multithreads mathematical model of temperature parameters control of a gas-field is developed in the paper. Dynamic certificates of wells and pipe lines are employed to distribute units according to the temperature. They are formed and supported in the actual status by means of the developed information-measuring and control system. An estimation procedure of reliability choice of temperature profile parameters, considering weight coefficients at modes positioning of heaters activity, is developed and applied in the Astrakhan gas-field conditions. The application of the mathematical model enables to eliminate invalid control actions on gas heating systems by using factual technological capabilities of gas heaters on well sites, and it provides high safety operation level of dangerous technological objects.

  15. Temperature-dependent gas transport performance of vertically aligned carbon nanotube/parylene composite membranes

    Science.gov (United States)

    Zhang, Lei; Yang, Junhe; Wang, Xianying; Zhao, Bin; Zheng, Guangping

    2014-08-01

    A novel composite membrane consisting of vertically aligned carbon nanotubes (CNTs) and parylene was successfully fabricated. Seamless filling of the spaces in CNT forests with parylene was achieved by a low-pressure chemical vapor deposition (CVD) technique and followed with the Ar/O2 plasma etching to expose CNT tips. Transport properties of various gases through the CNT/parylene membranes were explored. And gas permeances were independent on feed pressure in accordance with the Knudsen model, but the permeance values were over 60 times higher than that predicted by the Knudsen diffusion kinetics, which was attributed to specular momentum reflection inside smooth CNT pores. Gas permeances and enhancement factors over the Knudsen model firstly increased and then decreased with rising temperature, which confirmed the existence of non-Knudsen transport. And surface adsorption diffusion could affect the gas permeance at relatively low temperature. The gas permeance of the CNT/parylene composite membrane could be improved by optimizing operating temperature.

  16. Temperature-modulated direct thermoelectric gas sensors: thermal modeling and results for fast hydrocarbon sensors

    International Nuclear Information System (INIS)

    Direct thermoelectric gas sensors are a promising alternative to conductometric gas sensors. For accurate results, a temperature modulation technique in combination with a regression analysis is advantageous. However, the thermal time constant of screen-printed sensors is quite large. As a result, up to now the temperature modulation frequency (20 mHz) has been too low and the corresponding principle-related response time (50 s) has been too high for many applications. With a special design, respecting the physical properties of thermal waves and the use of signal processing similar to a lock-in-amplifier, it is possible to achieve response times of about 1 s. As a result, direct thermoelectric gas sensors with SnO2 as a gas-sensitive material respond fast and are reproducible to the propane concentration in the ambient atmosphere. Due to the path-independent behavior of the thermovoltage and the temperature, the measured thermopower of two sensors is almost identical

  17. Temperature-modulated direct thermoelectric gas sensors: thermal modeling and results for fast hydrocarbon sensors

    Science.gov (United States)

    Rettig, Frank; Moos, Ralf

    2009-06-01

    Direct thermoelectric gas sensors are a promising alternative to conductometric gas sensors. For accurate results, a temperature modulation technique in combination with a regression analysis is advantageous. However, the thermal time constant of screen-printed sensors is quite large. As a result, up to now the temperature modulation frequency (20 mHz) has been too low and the corresponding principle-related response time (50 s) has been too high for many applications. With a special design, respecting the physical properties of thermal waves and the use of signal processing similar to a lock-in-amplifier, it is possible to achieve response times of about 1 s. As a result, direct thermoelectric gas sensors with SnO2 as a gas-sensitive material respond fast and are reproducible to the propane concentration in the ambient atmosphere. Due to the path-independent behavior of the thermovoltage and the temperature, the measured thermopower of two sensors is almost identical.

  18. High temperature gas-effluent decontamination of volatile iodine forms by titanium dioxide sorbent

    International Nuclear Information System (INIS)

    There is actual problem of carrying out inorganic sorbents for cleaning gas flow from volatile iodine form. The sorbents could using for depressurization in the reactor's vessels by heavy accidents and in the gas-cleaning system of high-temperature gas reactor. Inorganic sorbents on base of of titanium dioxide was synthesised (trade mark - TERMOKSID-58). The sorbent has thermal stability, high temperature, high mechanical strength an good kinetic and aerodynamic characteristics. Statics and dynamic of adsorption of molecular iodine and methyl iodine under 100-400 deg C are studying. Sorption of molecular iodine has irreversible character. Efficiency of cleaning of molecular iodine and methyl iodine in embankment layers of TERMOOKSID-58 sorbent according a temperature, a concentration and a gas linear velocity were investigated

  19. 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

  20. Gas Flame Temperature Measurement Using Background Oriented Schlieren

    Directory of Open Access Journals (Sweden)

    A.S. Malik

    2011-01-01

    Full Text Available In this study, Background-Oriented Schlieren (BOS technique is employed to measure the temperature field of a methane flame. High speed camera and a wavelet noise background are used to achieve strong spatial and temporal resolution. The basic optical flow algorithm is modified to account for the intensity variation. This is because the flame flow creates a considerable intensity variation between the pair of images under correlation. Principles of geometric optics are used in order to get the index of refraction. The density information is recovered by slotting the Gladstone-Dale equation in filtered back projection. The computed temperature field measurements are shown as a function of time. Finally, the measured temperature is compared with probe measurements.

  1. Gas Temperature and Radiative Heat Transfer in Oxy-fuel Flames

    DEFF Research Database (Denmark)

    Bäckström, Daniel; Johansson, Robert

    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 and by an optical system based on FTIR-spectroscopy. The radiation intensity was measured by a Narrow Angle Radiometer and the gas radiation was calculated with a Statistical Narrow Band model. The overall agreement between the two temperature measurement techniques was good. The optical system showed a lower temperature than the suction pyrometer in the low velocity regions of the furnace, a difference which is likely to be an effect of the purge gas added in the optical probe. The measured temperature fluctuations were evaluated by modeling of the gas radiation. The influence from the measured fluctuations 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 for the turbulence-radiation interaction in the investigated flame.

  2. Effect of Ambient Temperature on the Performance of Gas Turbines Power Plant

    Directory of Open Access Journals (Sweden)

    Naeim Farouk Mohammed

    2013-01-01

    Full Text Available Efficiency and electric-power output of gas turbines vary according to the ambient conditions. The amount of these variations greatly affects electricity production, fuel consumption and plant incomes. The purpose of the present study is to investigate the effect of the ambient temperature on the performance of gas turbines. We observed that the power decreases due to reduction in air mass flow rate (the density of the air declines as temperature increases and the efficiency decreases because the compressor requires more power to compress air of higher temperature.

  3. Simultaneous removal of gaseous emissions and particulates from the exhaust gas of stationary Diesel engines. Final report NEFF project no. 527

    International Nuclear Information System (INIS)

    The object of the project was the development of a fibre filter for the effective removal of carbon particles from the waste gas of stationary diesel motors from which the nitrogen oxide had already been almost completely eliminated by means of a catalyst. The final report describes the development of the filter, the field trials and the introduction of the product onto the market. figs., tabs., 24 refs

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

    OpenAIRE

    WANG, Y.; Chung, A.; S. E. Paulson

    2010-01-01

    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, Na<...

  5. The Efficiency Analysis of the Exhaust Air Heat Pump System

    Directory of Open Access Journals (Sweden)

    Alo Mikola

    2014-12-01

    Full Text Available This paper is based on long term parameter measurements of the exhaust air heat pumps (EAHP system in a new built apartment building. The building was equipped with an exhaust air ventilation system and exhaust air heat pump for ventilation heat recover. The results of the measurements show that the COP of the EAHP is mainly related to the temperature graph of the heating system and the supply temperature of domestic hot water (DWH. During the measurement period some other impact factors, such as the quality of maintenance, the nighttime temperature graph of the heating system, the reduction of the exhaust air flows in case of low temperatures, mistakes in designing and low building quality, have also played a role. An analysis of energy consumption shows that in winter conditions the COP is about 3.0 and in the transition period about 3.3. The energy recovery value of the EAHP is 0.5.

  6. 40 CFR 1065.230 - Raw exhaust flow meter.

    Science.gov (United States)

    2010-07-01

    ...cooling. (2) If cooling causes exhaust temperatures above 202...compression-ignition engines, 2-stroke spark-ignition engines, and 4-stroke spark-ignition engines below 19 kW. (3) If cooling causes aqueous condensation, do...

  7. 40 CFR 1045.245 - How do I determine deterioration factors from exhaust durability testing?

    Science.gov (United States)

    2010-07-01

    ...deterioration factors from exhaust durability testing? 1045.245 Section...deterioration factors from exhaust durability testing? This section...laboratory. (3) In the case of dual-fuel or flexible-fuel...exhaust temperatures. For dual-fuel engines, you must...

  8. BP Neural Network based on PSO Algorithm for Temperature Characteristics of Gas Nanosensor

    Directory of Open Access Journals (Sweden)

    Weiguo Zhao

    2012-09-01

    Full Text Available To comprehensively understand the characteristics of gas nanosensor between temperature and sensitivity, this paper has developed a Backward Propagation (BP neural network based on Particle Swarm Optimization (PSO, which is applied to fitting the temperature-sensitivity characteristic of the SnO2 gas nanosensor mixed with benzene. The simulation results show the PSO can well optimize the structure of the BP network, and the fitting accuracy of the temperature of nanosensor using the acquired BP model is improved greatly and the optimized BP network has better generalization performance than the traditional BP network, and the acquired curve is both smooth and accurate? so the study shows that BP-PSO neural network is effective for fitting the temperature characteristics of gas nanosensor.

  9. Charge and structures of dust particles in a gas discharge at cryogenic temperatures

    Science.gov (United States)

    Antipov, S. N.; Asinovski?, É. I.; Kirillin, A. V.; Ma?orov, S. A.; Markovets, V. V.; Petrov, O. F.; Fortov, V. E.

    2008-04-01

    A dusty plasma in a dc gas discharge is considered at low (cryogenic) temperatures of the gas. The formation of dusty plasma structures consisting of monodisperse poly(styrene) particles ( d = 5.44 ?m) in a dc glow discharge is experimentally investigated at cryogenic temperatures in the range from 4.2 to 77 K, and the results obtained are presented. The ion velocity distribution function and the charging of dust particles at cryogenic temperatures are calculated using the molecular dynamics method. The primary attention is focused on the correct inclusion of ion-atom collisions in the analysis. This is essential to the understanding of the main mechanisms of the experimentally observed increase in the density of dust particles with decreasing temperature of the gas in the discharge.

  10. Charge and structures of dust particles in a gas discharge at cryogenic temperatures

    International Nuclear Information System (INIS)

    A dusty plasma in a dc gas discharge is considered at low (cryogenic) temperatures of the gas. The formation of dusty plasma structures consisting of monodisperse poly(styrene) particles (d = 5.44 ?m) in a dc glow discharge is experimentally investigated at cryogenic temperatures in the range from 4.2 to 77 K, and the results obtained are presented. The ion velocity distribution function and the charging of dust particles at cryogenic temperatures are calculated using the molecular dynamics method. The primary attention is focused on the correct inclusion of ion-atom collisions in the analysis. This is essential to the understanding of the main mechanisms of the experimentally observed increase in the density of dust particles with decreasing temperature of the gas in the discharge

  11. Temperatures Data Preprocessing for Short-Term Gas Consumption Forecast.

    Czech Academy of Sciences Publication Activity Database

    Šim?nek, Milan; Pelikán, Emil

    - : IEEE, 2008, s. 1192-1196. ISBN 978-1-4244-1666-0. [ISIE 2008. IEEE International Symposium on Industrial Electronics. Cambridge (GB), 30.06.2008-02.07.2008] R&D Projects: GA AV ?R 1ET400300513 Institutional research plan: CEZ:AV0Z10300504 Keywords : data preprocessing * temperature * case - based reasoning * hourly profiles Subject RIV: IN - Informatics, Computer Science

  12. Global temperature projections with increasing and decreasing greenhouse gas emissions.

    Science.gov (United States)

    Met Office Hadley Centre

    This animation shows predicted changes in temperature across the globe, relative to pre-industrial levels, under two different emissions scenarios in the COP 17 climate model. The first is with emissions continuing to increase through the century. The second is with emissions declining through the century.

  13. Effects of Interactions on the Critical Temperature of a Trapped Bose Gas

    International Nuclear Information System (INIS)

    We perform high-precision measurements of the condensation temperature of a harmonically trapped atomic Bose gas with widely tunable interactions. For weak interactions we observe a negative shift of the critical temperature in excellent agreement with mean-field theory. However for sufficiently strong interactions we clearly observe an additional positive shift, characteristic of beyond-mean-field critical correlations. We also discuss nonequilibrium effects on the apparent critical temperature for both very weak and very strong interactions.

  14. Combustion Temperature Effect of Diesel Engine Convert to Compressed Natural Gas Engine

    OpenAIRE

    Semin; Abdul R. Ismail; Bakar, Rosli A.

    2009-01-01

    Effect of combustion temperature in the engine cylinder of diesel engine convert to Compressed Natural Gas (CNG) engine was presents in this study. The objective of this study was to investigate the engine cylinder combustion temperature effect of diesel engine convert to CNG engine on variation engine speed. Problem statement: The hypothesis was that the lower performance of CNG engine was caused by the effect of lower in engine cylinder temperature. Are the CNG engine is lower cylinder temp...

  15. Pressure dependence of the melting temperature of solids - Rare-gas solids

    Science.gov (United States)

    Schlosser, Herbert; Ferrante, John

    1991-01-01

    A method presented by Schlosser et al. (1989) for analyzing the pressure dependence of experimental melting-temperature data is applied to rare-gas solids. The plots of the logarithm of the reduced melting temperature vs that of the reduced pressure are straight lines in the absence of phase transitions. The plots of the reduced melting temperatures for Ar, Kr, and Xe are shown to be approximately straight lines.

  16. Temperatures of Mediterranean Volcanic Hydrothermal Systems Reflected by Gas Geothermometry

    Science.gov (United States)

    Fiebig, J.; Tassi, F.; D'Alessandro, W.; Vaselli, O.; Woodland, A. B.

    2011-12-01

    We have addressed the genetic relationship between H2, H2O, CO, CO2, n-alkanes and n-alkenes in volcanic-hydrothermal gases emitted from Nisyros (Greece), Vesuvio, Campi Flegrei and Pantelleria (all Italy). Methane attains chemical and isotopic equilibrium with CO2 in the associated hydrothermal systems within the single liquid phase. Calculated aquifer temperatures at depth are ~360°C at Nisyros, 420-460°C at Vesuvio, ~450°C at Campi Flegrei and ~540°C at Pantelleria. CH4-CO2 equilibrium temperatures are in agreement with propane/propene concentration ratios. Temperatures >400°C are additionally confirmed by ethane/ethene ratios. In contrast to CH4-CO2, metastable equilibration of the alkane/alkene pairs takes place in the saturated water vapor phase. Overall agreement of vapor and liquid equilibration temperatures suggests that boiling in the investigated high-enthalpy hydrothermal systems is essentially isothermal. Our results imply that the chemical and isotopic CH4-CO2 geothermometer is least prone to re-equilibration reactions occurring in the vapor phase after vapor separation. Redox conditions during these re-equilibration reactions are homogeneously buffered by H2/H2O ratios of the vapor phase, which, in turn, are controlled by those of the parental liquid phase and by the degree of superimposed vapor separation. Amongst the redox pairs investigated, CO/CO2 is most prone to secondary vapor phase equilibration. Our results imply that the isotopic CH4-CO2 geothermometer has the potential to record temperatures of aquifers associated with dormant volcanoes. Alkene/alkane and H2/H2O concentration ratios should be measured along with CH4 and CO2 to prove independently whether isotopic equilibrium has been attained.

  17. Preliminary study on helium turbomachine for high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    In the high temperature gas-cooled reactor (HTGR), gas turbine cycle is a new concept in the field of nuclear power. It combines two technologies of HTGR and gas turbine cycle, which represent the state-of-the-art technologies of nuclear power and fossil fuel generation respectively. This approach is expected to improve safety and economy of nuclear power plant significantly. So it is a potential scheme with competitiveness. The heat-recuperated cycle is the main stream of gas turbine cycle. In this cycle, the work medium is helium, which is very different from the air, so that the design features of the helium turbomachine and combustion gas turbomachine are different. The paper shows the basic design consideration for the heat-recuperated cycle as well as helium turbomachine and highlights its main design features compared with combustion gas turbomachine

  18. Stability of test environments for performance evaluation of materials for the modular high-temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Stability of the primary helium-based coolant test gas for use in performance ests of materials for the Modular High-Temperature Gas-Cooled Reactor (MHTGR) was determined. Results of tests of the initial gas chemistry from General Atomics (GA) at elevated temperatures, and the associated results predicted by the SOLGASMIX trademark modelling package are presented. Results indicated that for this gas composition and at flow rates obtainable in the test loop, 466 ± 24C is the highest temperature that can be maintained without significantly altering the specified gas chemistry. Four additional gas chemistries were modelled using SOLGASMIX trademark

  19. Gas temperature determination in microwave discharges at atmospheric pressure by using different Optical Emission Spectroscopy techniques

    International Nuclear Information System (INIS)

    Non-thermal plasmas sustained at atmospheric pressure are considered as a very promising technology for different purposes, in which the knowledge of the gas temperature is an important issue. In this paper, the gas temperatures of different argon microwave (2.45 GHz) plasma torches were determined by using different Optical Emission Spectroscopy techniques. Thus, they were estimated through the analysis of N2+(B-X) and OH(A-X) molecular spectra. On the other hand, a method based on the measurement of the van der Waals broadening of 588.99 nm Na I line was employed, and the temperatures obtained from it were compared to the rotational temperatures derived from N2+(B-X) and OH(A-X) rotational bands. A reasonable good agreement was found between the values of temperatures obtained by using the 588.99 nm Na I line and those obtained from N2+ rotational band. - Highlights: • We measured the gas temperatures of different 2.45 GHz plasmas. • We obtained the gas temperature from N2 and OH molecular spectra. • We compared with an alternative method using 588.99 and 589.59 nm Na I lines. • A very good agreement between the values of Tgas obtained was found. • ?he alternative method could be very helpful in plasmas containing nitrogen

  20. Decrease in lower level density due to cooling of gas temperature by thermal dissociation of hydrogen in copper vapor laser

    International Nuclear Information System (INIS)

    A gas temperature calculation is carried out in the copper vapor laser (CVL) with a beam diameter of 80 mm in the case of H2 addition into the Ne buffer gas. The on-axis gas temperature decreases to 2800K with 1% concentration of H2, whereas the gas temperature is 3400K without H2. The on-axis lower level density decreases due to the cooling of the gas temperature. This decrease in the lower level density is thought to bring about a non annular beam profile in the case of H2 addition. (author)