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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)

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.

M.N.Khan

2010-12-01

2

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2010-01-01

3

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

International Nuclear Information System (INIS)

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

4

Exhaust-Gas Pressure and Temperature Survey of F404-GE-400 Turbofan Engine  

Science.gov (United States)

An exhaust-gas pressure and temperature survey of the General Electric F404-GE-400 turbofan engine was conducted in the altitude test facility of the NASA Lewis Propulsion System Laboratory. Traversals by a survey rake were made across the exhaust-nozzle exit to measure the pitot pressure and total temperature. Tests were performed at Mach 0.87 and a 24,000-ft altitude and at Mach 0.30 and a 30,000-ft altitude with various power settings from intermediate to maximum afterburning. Data yielded smooth pressure and temperature profiles with maximum jet temperatures approximately 1.4 in. inside the nozzle edge and maximum jet temperatures from 1 to 3 in. inside the edge. A low-pressure region located exactly at engine center was noted. The maximum temperature encountered was 3800 R.

Walton, James T.; Burcham, Frank W., Jr.

1986-01-01

5

High temperature-resistant materials for car exhaust gas catalysts; Hochtemperaturfeste Werkstoffe fuer Autoabgaskatalysatoren  

Energy Technology Data Exchange (ETDEWEB)

The aim of the work consisted of the development of a material for car exhaust gas catalysts which can be used in catalysts situated near the engine. Because of the occurrence of temperatures up to 1000 C in use, there are considerably higher requirements for this material than for previous materials. Titanium in the form of foil and metal mesh and nickel in the form of metal mesh was tested as substrate materials. Ti-hybrid, Ni and Cu were tested as diffusion blockers, and Pt noble metal coating as galvanic layer and as product of the thermal decomposition of a Pt complex salt free of chloride. It was found that Ti is not stable at a temperature of 1000 C and neither are the diffusion blockers. Ni with platinum plating does not change at 1000 C. The examination of the application technique of the Ni metal mesh gave no satisfactory conversion rates for Co, HC and NO{sub x}. Information was obtained in what conditions and in which geometrical shape metal mesh is suitable as the substrate geometry for exhaust gas catalysts. (orig.) [Deutsch] Das Ziel der Arbeiten bestand in der Entwicklung eines Werkstoffes fuer Autoabgaskatalysatoren, der in motornah angeordneten Katalysatoren eingesetzt werden kann. An diesen Werkstoff werden wegen der im Einsatz auftretenden Temperaturen bis 1000 C wesentlich hoehere Anforderugen als an die bisherigen Werkstoffe gestellt. Es wurden Ti in Form von Folie und Streckmetall sowie Ni in Form von Streckmetal als Substratwerkstoffe getestet. Als Diffusionssperren wurden Ti-Hybrid, Ni und Cu und als Edelmetallbeschichtung Pt als galvanische Schicht und als Produkt der thermischen Zersetzung eines chloridfreien Pt-Komplexsalzes getestet. Es zeigte sich, dass Ti bei der Temperaturbelastung von 1000 C nicht stabil ist, auch nicht die Diffusionssperren. Ni, platiniert, erfaehrt bei 1000 C keine Veraenderungen. Die anwendungstechnische Untersuchung des platinierten Ni-Streckmetalles ergab keine zufriedenstellenden Konvertierungsraten fuer CO, HC und NO{sub x}. Es wurden Erkenntnisse gewonnen, unter welchen Bedingungen und in welcher geometrischer Form sich Streckmetall als Substratgeometrie in Abgaskatalysatoren eignet. (orig.)

Einenkel, A.

1996-06-30

6

Exhaust gas filter  

International Nuclear Information System (INIS)

A filter material formed by joining glass clothes to both surfaces of a glass fiber non-woven fabric is used. The filter material is disposed at the inside of a square filter material support frame made of stainless steel. The filter material is attached in a zig-zag manner in the flowing direction of the exhaust gases so as to increase the filtration area. Separators, for example, made of stainless steel are inserted between the filter materials. The separator is corrugated so as to sandwich and support the filter materials from both sides by the ridged crests. The longitudinal bottom of the separator formed by corrugating it defines a flow channel of the exhaustion gases. The longitudinal bottom is also used as a channel for back blowing air. With such a constitution, combustion gases of radioactive miscellaneous solid wastes can be completely filtered. In addition, a back wash can be conducted under high temperature. (I.N.)

7

Processing of exhaust gas  

International Nuclear Information System (INIS)

Silicon carbide is an important component in exhaust gas filters for diesel engines. Norway produces and refines SiC, which is used in fireproof and ceramic industry and as an abrasive. It is also increasingly used in electronic industry. The emission from diesel engines consists of small spherical soot particles with an appendage of fuel, lubricating oil, water and sulphur compounds. These particles are intercepted by silicon carbide filters. There is a world-wide demand for environmentally friendly diesel engines and a growing demand for silicon carbide. From 2002, the EU permits a maximum emission of 0.025 grams per km of driving

8

Device for exhaust gas recycling  

Energy Technology Data Exchange (ETDEWEB)

A device for exhaust gas recycling is proposed which controls the amount of recycled exhaust gas in an internal combustion engine equipped with an injection unit so that a certain air factor is attained. The device comprises a closing element for the exhaust gas return conduit, which latter terminates into the intake manifold, this closing element being suitably constituted by a throttle valve and being directly connected to the adjusting lever or control rod of the injection pump. If this connection is established via a resilient linkage between the adjusting lever and the exhaust gas return valve, then the thus-recycled amount of exhaust gas can be dimensioned so that a specific quantity of recycled exhaust gas is associated with a specific angular position of the adjusting lever.

Banzhaf, W.; Stumpp, G.

1980-10-28

9

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

Directory of Open Access Journals (Sweden)

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.

S. Prabhakar

2011-10-01

10

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Prabhakar, S.; Annamalai, K.

2011-01-01

11

Gas turbine exhaust system silencing design  

International Nuclear Information System (INIS)

Gas turbines are the preferred prime mover in many applications because of their high efficiency, fuel flexibility, and low environmental impact. A typical mid-size machine might have a power rating of 80 MW, a flow of about 1000 kg/hr, and an exhaust temperature of over 500C. The most powerful single source of noise is generally the exhaust, which may generate over a kilowatt of acoustic energy. This paper reports that there are two important ways in which exhaust systems can radiate noise. The first is through the discharge of the exhaust duct, with the exhaust gas. Because of the large quantity of hot gas, the duct exit is always oriented vertically; it may be fairly high in the air in order to promote dispersion of the exhaust plume. This source is almost always attenuated by means of a silencer located somewhere in the ductwork. The second source of noise is often called breakout; it is the radiation of exhaust noise through the walls of the ducting. Breakout is most important for those sections of the exhaust duct which lie upstream of the silencer, where sound levels inside the ducting are highest. Both exhaust duct exit noise and breakout noise can be calculated from the sound power level of the gas turbine exhaust and the sound transmission loss (TL) of the silencer and ducting

12

Instantaneous exhaust temperature measurements using thermocouple compensation techniques  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper discusses a method of measuring the instantaneous exhaust gas temperature by thermocouples. Measuring the exhaust gas temperature is useful for a better understanding of engine processes. Thermocouples do not measure the instantaneous exhaust gas temperature because of their limited dynamic response. A thermocouple compensation technique has been developed to estimate the time constant in situ. This method has been commissioned in a simulation study and a controlled experiment with...

Kar, K.; Roberts, S.; Stone, R.; Oldfield, M.; French, B.

2004-01-01

13

Clean exhaust gas  

International Nuclear Information System (INIS)

Brown-coal coke has properties that make it a suitable base material for adsorbents and catalysts of the types used for the purification of flue gas from waste incineration plants. It is less expensive than activated carbon. Brown-coal coke makes it possible to keep pollutant concentrations well within the limit values laid down in the relevant regulations. (orig.)

14

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

Science.gov (United States)

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

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

2012-04-17

15

High temperature sensors for exhaust diagnosis  

Energy Technology Data Exchange (ETDEWEB)

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.

Svenningstorp, Henrik

2000-07-01

16

Simultaneous temperature and exhaust-gas recirculation-measurements in a homogeneous charge-compression ignition engine by use of pure rotational coherent anti-Stokes Raman spectroscopy  

Science.gov (United States)

Pure rotational coherent anti-Stokes Raman spectroscopy was used for the simultaneous determination of temperature and exhaust-gas recirculation in a homogeneous charge-compression ignition engine. Measurements were performed in a production-line four-cylinder gasoline engine operated with standard gasoline fuel through small optical line-of-sight accesses. The homogenization process of fresh intake air with recirculated exhaust gas was observed during the compression stroke, and the effect of charge temperature on combustion timing is shown. Single-pulse coherent anti-Stokes Raman spectroscopy spectra could not only be taken in the compression stroke but also during the gas-exchange cycle and after combustion. Consequently, the used method has been shown to be suitable for the investigation of two of the key parameters for self-ignition, namely temperature and charge composition.

Weikl, Markus C.; Beyrau, Frank; Leipertz, Alfred

2006-05-01

17

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

Science.gov (United States)

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

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

2013-01-01

18

Diesel exhaust-gas purification system  

Energy Technology Data Exchange (ETDEWEB)

The design of a diesel exhaust gas purification system is presented. It will provide 2000 scfm of dry, anerobic gas (essentially nitrogen) for use in air drilling operations where drill pipe corrosion is a problem, such as geothermal applications. The system is operable in the field and may be transported via highways. It will operate at ambient temperatures up to 110/sup 0/F and requires no water - diesel fuel is used to combust excess oxygen and to generate electricity for the system. Gas production costs, including capital amortization, operations, fuel and maintenance (for reasonable utilization) are about $1.50/1000 scf.

Doherty, B.J.

1982-07-01

19

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel plasma-driven catalysis (PDC) reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD) reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2) film prepared by radiofrequency (RF) magnetron sputtering was coated on t...

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

2013-01-01

20

Differential analysis of hydrocarbons in the exhaust gas of diesel motors before reaching operation temperature. Differenzierte Analyse der Kohlenwasserstoffe im Abgas von nicht betriebswarmen Dieselmotoren  

Energy Technology Data Exchange (ETDEWEB)

For the investigation of the exhaust gas composition from instationary states of diesel motors before reaching operating temperature, an extraction system for samples has been developed from single working cycles. The main aim of the exhaust gas analyses was the differentiated observation of the hydrocarbons and determination of aldehydes as a whole. The main interest was given to those hydrocarbons occurring to higher concentrations compared to the fuel in the exhaust gas. Two motors with direct injection have been observed, a motor with prechamber was used for preliminary tests. The particularly high expulsion of non-oxidized pyrolysis products (benzene, toluene, styrene, and alkenes of lower hydrocarbons) in cold starting of accelerating with cold motor, can be reduced by a temperature-dependent dose of the start excess and suitable regulation of the injection during acceleration. The aldehyde emissions also increase at high gas temperatures and with sufficiently high air ratios. Preheating the suction air proved to be the most effective measure to reduce of the hydrocarbon and aldehyde emissions of cold motors.

Zoerner, E.

1980-01-01

 
 
 
 
21

40 CFR 86.111-90 - Exhaust gas analytical system.  

Science.gov (United States)

...2010-07-01 false Exhaust gas analytical system. 86.111-90 Section 86...Procedures § 86.111-90 Exhaust gas analytical system. (a) Schematic drawings...schematic drawing of the exhaust gas analytical system for analysis of...

2010-07-01

22

40 CFR 86.211-94 - Exhaust gas analytical system.  

Science.gov (United States)

...2010-07-01 false Exhaust gas analytical system. 86.211-94 Section 86...Procedures § 86.211-94 Exhaust gas analytical system. The provisions of § 86...analyzer is optional. The exhaust gas analytical system must contain components...

2010-07-01

23

40 CFR 86.511-90 - Exhaust gas analytical system.  

Science.gov (United States)

...2010-07-01 false Exhaust gas analytical system. 86.511-90 Section 86...Procedures § 86.511-90 Exhaust gas analytical system. (a) Schematic drawings...schematic drawing of the exhaust gas analytical system for analysis of...

2010-07-01

24

Exhaust gas recirculation system for an internal combustion engine  

Science.gov (United States)

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.

Wu, Ko-Jen

2013-05-21

25

Wet process for the desulfurization of exhaust gas  

Energy Technology Data Exchange (ETDEWEB)

A wet process for the desulfurization of exhaust gas comprising the following operation steps so as to eliminate and recover sulfur dioxide from exhaust gas containing it: (A) a step of absorbing sulfur dioxide by contacting exhaust gas with an absorbent mainly containing potassium salts of tartaric acid having a ph value of 4.5-6.5, (B) a step of recovering sulfur dioxide by drawing out a part of the absorbent in the step (A) and heating it to liberate and recover sulfur dioxide, (C) a step of circulating the absorbent by cooling the absorbent from the step (B) to a temperature suitable for the absorption of exhaust gas and recycling it to the step (A).

Masuhara, I.; Wakabayashi, A.

1981-07-07

26

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)

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.

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

2011-07-01

27

Low exhaust temperature electrically heated particulate matter filter system  

Science.gov (United States)

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

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

2012-02-14

28

40 CFR 89.416 - Raw exhaust gas flow.  

Science.gov (United States)

...Environment 20 2010-07-01 2010-07-01 false Raw exhaust gas flow. 89.416 Section 89.416 Protection...COMPRESSION-IGNITION ENGINES Exhaust Emission Test Procedures § 89.416 Raw exhaust gas flow. The exhaust gas flow shall be...

2010-07-01

29

High Temperature Resistant Exhaust Valve Spindle  

DEFF Research Database (Denmark)

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.

Bihlet, Uffe Ditlev

2014-01-01

30

40 CFR 86.111-94 - Exhaust gas analytical system.  

Science.gov (United States)

...consists of a gas chromatograph...detector. The analysis for formaldehyde...ultraviolet (UV) detection. The exhaust gas analytical system...detector. The analysis for formaldehyde...ultraviolet (UV) detection. The exhaust gas analytical...

2010-07-01

31

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

Energy Technology Data Exchange (ETDEWEB)

The nitrogen oxides (NO{sub x}) emissions of compression ignition (CI) engines fuelled 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 NO{sub x} 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 carded 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{sup o}C which was chosen as a typical low exhaust gas temperature of diesel engines operating at part load. The engine operating condition (speed, load) was the same in all the tests and the reactor product gas was examined as a function of the reactor fuel flow rate and the composition of fuel and engine exhaust gas. Up to 17% hydrogen content of the reformer product was achieved and the results indicated that the main reactions in the reformer were the exothermic complete oxidation of part of the fuel and the endothermic steam reforming reaction. Reforming of RME produced more hydrogen with higher fuel conversion efficiency compared to ULSD reforming. (author)

Tsolakis, A.; Megaritis, A. [University of Birmingham (United Kingdom). School of Engineering

2004-11-01

32

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

33

SST-1 Gas feed and Gas Exhaust system  

International Nuclear Information System (INIS)

SST-1 tokamak is a long pulse tokamak designed for the plasma operation up to 1000 sec duration. Gas feed system and gas exhaust management will play a very crucial role during plasma discharge. During the different type of operations of tokamak like wall conditioning, diverter operation and neutral beam injection, a large amount of gas will be fed into the vacuum chamber at different locations. Also during plasma operations, the gas will be fed both in continues and pulse mode. Gas feed will be carried out mainly using piezo-electric valves controlled by PXI based data acquisition and control system. Such operations will lead to a huge amount gas exhaust by the main system which requires good exhaust facility to searches, great care should be taken in constructing both. Also initial pumping of cryostat and vacuum vessel of SST-1 will release a large amount of gas. Exhausted gases from SST -1 will be Hydrogen, Nitrogen, Mixture gases or some toxic gases. Dedicated exhaust system controlling the different gases are installed. Special treatment of hazardous/explosive gases is done before releasing to the atmosphere. This paper describes design and implementations of the complete gas feed and exhaust system of SST-1.

34

46 CFR 63.25-7 - Exhaust gas boilers.  

Science.gov (United States)

... 2010-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7...MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas...

2010-10-01

35

40 CFR 86.111-94 - Exhaust gas analytical system.  

Science.gov (United States)

...2010-07-01 false Exhaust gas analytical system. 86.111-94 Section 86...Procedures § 86.111-94 Exhaust gas analytical system. Link to an amendment published...schematic drawing of the exhaust gas analytical system for samples from bag...

2010-07-01

36

Low temperature operation and exhaust emission  

Energy Technology Data Exchange (ETDEWEB)

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

Laurikko, J.

1987-01-01

37

Gas sensors based on tin dioxide for exhaust gas application, modeling of response for pure gases and for mixtures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper concerns tin dioxide gas sensors for automotive exhaust gas application. It consists in elaborating robust sensors on alumina substrate by screen-printing technology. Sensors have been tested on a synthetic gas bench which is able to generate high gas velocity and gases at high temperatures close to real exhaust gas conditions. The responses of the sensors to three gases were modeled, and the classical model of electrical conductivity with one reducing or oxidizing pollutant gas wa...

Viricelle, Jean-paul; Valleron, Arthur; Pijolat, Christophe; Breuil, Philippe; Ott, Se?bastien

2012-01-01

38

Cycle-by-cycle variations in exhaust temperatures using thermocouple compensation techniques  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Exhaust gas temperatures in a 1.4 L, sparked ignition engine have been measured using fine wire thermocouples at different loads and speeds. However the thermocouples are not fast enough to resolve the rapid change in exhaust temperature. This paper discusses a new thermocouple compensation technique to resolve the cycle-by-cycle variations in exhaust temperature by segmentation. Simulation results show that the technique can find the lower time constants during blowdown, reducing the bias fr...

Kar, K.; Swain, A.; Raine, R.; Roberts, S.; Stone, R.

2006-01-01

39

Interrelation of exhaust-gas constituents  

Science.gov (United States)

This report presents the results of an investigation conducted to determine the interrelation of the constituents of the exhaust gases of internal-combustion engines and the effect of engine performance on these relations. Six single-cylinder, liquid-cooled tests engines and one 9-cylinder radial air-cooled engine were tested. Various types of combustion chambers were used and the engines were operated at compression ratios from 5.1 to 7.0 using spark ignition and from 13.5 to 15.6 using compression ignition. The investigation covered a range of engine speeds from 1,500 to 2,100 r.p.m. The fuels used were two grades of aviation gasoline, auto diesel fuel, and laboratory diesel fuel. Power, friction, and fuel-consumption data were obtained from the single-cylinder engines at the same time that the exhaust-gas samples were collected.

Gerrish, Harold C; Voss, Fred

1938-01-01

40

Exhaust gas treatment by electrical discharge techniques  

International Nuclear Information System (INIS)

Exhaust gases have been treated by two kinds of electrical discharge, surface discharge and DC positive streamer corona, in order to remove NOx. For the former case, the exhaust gas containing 20 ppm and 45 ppm NO, respectively was used. Treatment efficiency depended on a power supply frequency and applied voltage. The highest NO removal rate of 100 % was achieved, however, in a dry mode almost all NO was oxidized into NO2. Using the DC and DC with series gap, the treatment efficiency strongly depended on a corona discharge mode; a desired streamer was ignited in a wire-plate reactor, using wire pre-treatment or series gap, respectively. For DC power supply, the high voltage electrode material was investigated in order to obtain the highest treatment efficiency. Among the studied materials, tungsten turned out be the best for igniting the most stable streamer mode according to tungsten trioxide identified on the wire surface. (Authors)

 
 
 
 
41

PIXE analysis of exhaust gas from diesel engine  

International Nuclear Information System (INIS)

The variation of elemental concentrations in exhaust gas of a Diesel engine with the outputs was studied. Particulates in high temperature gas were collected on silica fiber filters and analyzed by PIXE method. Concentrations of S and V were nearly proportional to particulate masses and fuel consumption rates per discharging rates of exhaust gas respectively. While, concentrations of Fe and Mn were markedly increased together with engine outputs, and Mn/Fe ratios were nearly equal to those of the material of piston rings and the cylinder liner. Concentrations of the elements contained in lubricant, such as Ca and Mo, were also conspicuously increased with the outputs. It was shown that PIXE analysis is a useful tool for engine diagonostics owing to its high sensitive multi-elemental availability without chemical treatments. (author)

42

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.

43

Exhaust gas recirculation in a homogeneous charge compression ignition engine  

Science.gov (United States)

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.

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

44

Exhaust gas emissions of a vortex breakdown stabilized combustor  

Science.gov (United States)

Exhaust gas emission data are described for a swirl stabilized continuous combustor. The combustor consists of confined concentric jets with premixed fuel and air in the inner jet and air in the outer jet. Swirl may be induced in both inner and outer jets with the sense of rotation in the same or opposite directions (co-swirl and counter-swirl). The combustor limits NO emissions by lean operation without sacrificing CO and unburned hydrocarbon emission performance, when commercial-grade methane and air fired at one atmosphere without preheat are used. Relative swirl direction and magnitude are found to have significant effects on exhaust gas concentrations, exit temperatures, and combustor efficiencies. Counter-swirl gives a large recirculation zone, a short luminous combustion zone, and large slip velocities in the interjet shear layer. For maximum counter-swirl conditions, the efficiency is low.

Yetter, R. A.; Gouldin, F. C.

1976-01-01

45

Gas exhaustion system of reactor container  

International Nuclear Information System (INIS)

In a BWR type reactor, a connection pipe is disposed from a dry well and a wet well to a main steam pipeline, and a reactor container isolation valve is disposed to the pipeline. Excess pressure in the reactor container is released to a turbine condensator, to condensate steams in the condensator and remove water soluble radioactive materials. In addition, radioactive materials are reduced due to decay by temporarily storage in the turbine condensator. Radioactive materials in an incondensible gas are sufficiently removed by a gaseous waste processing system and the gas is released to the atmosphere through a main exhaustion tower. Pressure in the container is reduced by releasing the excess pressure to the turbine condensator, which prevents failure due to excessive pressure. (N.H.)

46

Concepts of exhaust gas cleaning procedures; Konzepte der Abgasreinigungsverfahren  

Energy Technology Data Exchange (ETDEWEB)

The continuous forward projecting of the legal emissions requirements contributed to a persistent new development and further development within the area of exhaust gas processes. Within the last 10 to 15 years, further aspects such as optimization of means of production or energy as design characteristics of the exhaust gas cleaning systems came along. The report under consideration gives an overview of the exhaust gas cleaning procedures in Europe and shows when which procedure can be used. Furthermore, selection criteria and selection procedures of exhaust gas cleaning systems are shown.

Karpf, Rudi; Krueger, Tina; Conrad, Yannick [ete.a Ingenieurgesellschaft fuer Energie- und Umweltengineering und Beratung mbH, Lich (Germany)

2013-03-01

47

Temperature controlled exhaust heat thermoelectric generation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The amount of energy wasted through the exhaust of an Internal Combustion Engine (ICE) vehicle is roughly the same as the mechanical power output of the engine. The high temperature of these gases (up to 1000??C) makes them intrinsically apt for energy recovery. The gains in efficiency for the vehicle could be relevant, even if a small percentage of this waste energy could be regenerated into electric power and used to charge the battery pack of a Hybrid or Extended Range Electric Vehic...

Brito, F. P.; Martins, Jorge; Gon Alves, L. M.; Sousa, R.

2012-01-01

48

30 CFR 7.102 - Exhaust gas cooling efficiency test.  

Science.gov (United States)

...2010-07-01 2010-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102 Mineral Resources ...Electric Equipment is Required § 7.102 Exhaust gas cooling efficiency test. (a) Test procedures. (1) Follow the...

2010-07-01

49

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

Science.gov (United States)

The ideal internal combustion (IC) engine (Otto Cycle) efficiency ?IC= 1-(1/r)^(?-1) is only a function of engine compression ratio r=Vmax/Vmin and exhaust gas specific heat ratio ?= cP/cV. Typically r= 8, ?= 1.4, and ?IC= 56%. Unlike the Carnot Cycle where ?Carnot= 1-(TC/TH) for a heat engine operating between hot and cold heat reservoirs at TH and TC, respectively, ?IC is not a function of the exhaust gas temperature. Instead, the exhaust gas temperature depends only on the intake gas temperature (ambient), r, ?, cV, and the combustion energy. The ejected exhaust gas heat is thermally decoupled from the IC engine and conveyed via the exhaust system (manifold, pipe, muffler, etc.) to ambient, and the exhaust system is simply a heat engine that does no useful work. The maximum fraction of fuel energy that can be extracted from the exhaust gas stream as useful work is (1-?IC) x?Carnot= 32% for TH= 850 K (exhaust) and TC= 370 K (coolant). This waste heat can be recovered using a heat engine such as a thermoelectric generator (TEG) with ?TEG0 in the exhaust system. A combined IC engine and TEG system can generate net useful work from the exhaust gas waste heat with efficiency ?WH= (1-?IC) x?Carnot x?TEG, and this will increase the overall fuel efficiency of the total system. Recent improvements in TEGs yield ?TEG values approaching 15% giving a potential total waste heat conversion efficiency of ?WH= 4.6%, which translates into a fuel economy improvement approaching 5%.

Meisner, G. P.

2013-03-01

50

40 CFR 86.511-90 - Exhaust gas analytical system.  

Science.gov (United States)

...methanol consists of a gas chromatograph (GC...ionization detector. The analysis for formaldehyde is...derivatives using ultraviolet (UV) detection. The exhaust gas analytical system shall...to nitric oxide before analysis. Other types of...

2010-07-01

51

40 CFR 86.111-90 - Exhaust gas analytical system.  

Science.gov (United States)

...methanol consists of a gas chromatograph (GC...ionization detector. The analysis for formaldehyde is...derivatives using ultraviolet (UV) detection. The exhaust gas analytical system shall...to nitric oxide before analysis. Other types of...

2010-07-01

52

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Science.gov (United States)

...Methane Measurement Using Gas Chromatography” (1994...allowed provided that sample gas temperature is maintained...if their exclusion is based upon good engineering...listed for the exhaust gas CVS systems in § 86...exchanger is used, the gas mixture temperature,...

2010-07-01

53

30 CFR 36.49 - Tests of exhaust-gas dilution system.  

Science.gov (United States)

...exhaust-gas dilution system. 36.49 Section...EVALUATION, AND APPROVAL OF MINING PRODUCTS APPROVAL...exhaust-gas dilution system. The performance and adequacy of the exhaust-gas dilution system shall be determined...

2010-07-01

54

New catalysts for exhaust gas cleaning  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

1996-12-31

55

Exhaust of NOx from High-Temperature Wind Tunnels  

Science.gov (United States)

Theoretical calculations were performed in order to estimate the concentrations of three main constituents of NOx (NO, NO2 and N2O) in the exhaust gas produced by two kinds of hypersonic wind tunnels. One of them had an arc-heater, and the other a pebble-heater. Estimations were performed for the equilibrium air in the plenum chamber, for the equilibrium and nonequilibrium nozzle flows, and for the final exhaust gas. Measurements in the exhaust gas of the arc-heated wind tunnel show that the total concentration of NOx (NO and NO2) was of the order of 10,000 ppm, depending on the conditions of operation. Two simple models are proposed to explain the origin of such a high level of NOx in the exhaust. It is shown that a model taking account of the isothermal compression of the exhaust gas in rotary pumps of the vacuum system can predict the formation of high concentrations of NOx.

Matsuzaki, Ri'ichi

1987-11-01

56

Development of Exhaust Gas Driven Absorption Chiller-Heater  

Science.gov (United States)

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.

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

57

IC ENGINE SUPERCHARGING AND EXHAUST GAS RECIRCULATION USING JET COMPRESSOR  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2010-01-01

58

Plant for exhaust gas detoxification. Anlage zur Abgasentgiftung  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to create a device for controlling the quantity of exhaust gas feed back in an internal combustion engine, which makes it possible to supply exactly dosed quantities of exhaust gas in part load operation, but not on tickover and on full load of the internal combustion engine, matching the load range of the suction side. According to the invention, this problem is solved by 2 valves feeding back exhaust gas independently of each other being provided, each with a pneumatic setting motor, whose pressure space is connected via control pipe to the suction pipe. The two pressure extraction positions connected to the control pipes are situated in the range of movement of the throttle valve upstream of its closed position, in the suction pipe wall. The valve works with a diaphragm, which actuates the moving part of the valve and is preferably separate from the exhaust gases. (HWJ).

Stumpp, G.

1981-07-16

59

Low-pressure-ratio regenerative exhaust-heated gas turbine  

Energy Technology Data Exchange (ETDEWEB)

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

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

1991-01-01

60

Fast exhaust channel optical absorption method and apparatus to study the gas exchange in large diesel engines  

Science.gov (United States)

An optical absorption spectroscopic method and apparatus with shorter than 1 ms response time have been used to study the gas exchange processes in realistic conditions for a single cylinder of a large diesel engine. The method is based on measuring the differential line-of-sight optical uv absorption of the exhaust-gas-contained SO2 as a function of time in the exhaust port area just after the exhaust valves. The optical absorption by SO2 is determined from light transmission measurements at 280 and 340 nm performed through optical probes installed into the exhaust channel wall. The method has been applied to a continuously fired, large, medium speed production-line-type diesel engine with 990 kW rated power. The test engine was operated with standard light fuel oil (MDO Termoshell) and with light fuel oil treated with a sulfur additive {Di-Tert-Butyldisulfid [(CH3)3C]2S2}. The latter was to improve the optical absorption signals without increasing the fouling of the exhaust channel optical probes as in the case of heavier fuel oil qualities. In the reported case of a four-stroke diesel engine measurement results show that the method can provide time-resolved information of the SO2 density in the exhaust channel and thus give information on the single-cylinder gas exchange. During the inlet and exhaust valve overlap period the moment of fresh air entering into the measurement volume can be detected. If independent exhaust gas temperature and pressure data are available, the absorption measurements can readily be used for determining the burnt gas fraction in the exhaust channel. In this work the possibility of using the optical absorption measurement to determine the instaneous exhaust gas temperature was studied. Based on known fuel properties and conventional averaged SO2 measurements from the exhaust channel a known concentration of SO2 was assumed in the exhaust gas after the exhaust valves opening and before the inlet and exhaust valves overlap period. Together with an exhaust gas pressure measurement the optical absorption signal was used to determine the instaneous exhaust gas temperature. Due to the minimal modifications needed by the engine for optical access, and continuously fired operation with relevant power levels and realistic fuel qualities, this measurement method, with some further development, can be useful to obtain time-resolved data from the exhaust channel of real production-line-type diesel engines.

Vattulainen, J.; Hernberg, R.; Hattar, C.; Gros, S.

1998-01-01

 
 
 
 
61

Session 4: On-board exhaust gas reforming for improved performance of natural gas HCCI engines  

Energy Technology Data Exchange (ETDEWEB)

Although natural gas (NG) is a non-renewable energy source, it is still a very attractive alternative fuel for transportation - it is inexpensive, abundant, and easier to refine than petroleum. Unfortunately the minimum spark energy required for NG ignition is higher than for liquid fuels, and engine performance is reduced since the higher volume of NG limits the air breathing capacity of the cylinders. On the other hand, the flammability range of NG is wider than for other hydrocarbons, so the engine can operate under leaner conditions. Environmentally, the use of NG is particularly attractive since it has a low flame temperature (resulting in reduced NO{sub x} emissions) and a low carbon content compared to diesel or gasoline (resulting in less CO, CO{sub 2} and particulate). In addition, NG is easily made sulphur-free, and has a high octane rating (RON = 110-130) which makes it suitable for high compression engine applications. Exhaust gas recirculation (EGR) into an engine is known to reduce both flame temperature and speed, and therefore produce lower NO{sub x} emissions. In general, a given volume of exhaust gas has a greater effect on flame speed and NO{sub x} emissions than the same quantity of excess air, although there is a limit to the amount of exhaust gas recirculation that can be used without inhibiting combustion. However, hydrogen addition to exhaust gas recirculation has been proved to reduce emissions while increasing flame speed, so improving both the emissions and the thermal efficiency of the engine. On-board reforming of some of the fuel, by reaction with exhaust gas during EGR, is a novel way of adding hydrogen to an engine. We have carried out reforming tests on mixtures of natural gas and exhaust gas at relatively low temperatures (400-600 C), to mimic the low availability of external heat within the integrated system. The reforming catalyst is a nickel-free formulation, containing precious metals promoted by metal oxides. The roles of water, oxygen and methane have been studied, as a function of space velocity, allowing us to assess the relative contributions of partial oxidation, steam reforming and water gas shift to the overall process of hydrogen formation. From this study we are able to identify the optimum auto-thermal conditions for the reforming process, and predict the behaviour of the reformer under different phases of engine operation. The reforming catalyst has been scaled up from a packed bed of granules to a full-sized monolithic reactor, which has been close-coupled with a Jaguar V6 engine. This integrated prototype has been tested with the engine running on natural gas in HCCI (homogeneous charge compression ignition) mode. The reformer adds 5-15% hydrogen to the recirculated exhaust gas, resulting in substantial improvements in the performance and emissions of the engine. (authors)

Amieiro, A.; Golunski, S.; James, D. [Johnson Matthey Technology Centre, Sonning Common, Reading (United Kingdom); Miroslaw, Wyszynski; Athanasios, Megaritis; Peucheret, S. [Birmingham Univ., School of Engineering, Future Power Systems Research Group (United Kingdom); Hongming, Xu [Jaguar Cars Ltd, W/2/021 Engineering Centre, Whitley, Coventry (United Kingdom)

2004-07-01

62

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

Science.gov (United States)

...increasingly stringent NO X emission standards for gas turbofan engines with maximum...Subpart C--Exhaust Emissions (New Aircraft Gas Turbine Engines) 0 8...rO. (e) Smoke exhaust emissions from each gas turbine engine of the...

2012-12-31

63

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

64

40 CFR 86.509-90 - Exhaust gas sampling system.  

Science.gov (United States)

...tolerance.) (2) The gas mixture temperature, measured at...start of the test. The gas mixture temperature variation from...condensation when testing natural gas and liquefied petroleum...prevent water condensation is based on the lowest...

2010-07-01

65

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

Science.gov (United States)

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

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

2000-10-01

66

Plasma exhaust gas processing for fusion reactors. Developments and problems  

International Nuclear Information System (INIS)

Recent progress at the Tritium Laboratory Karlsruhe is presented on the development of tritium technology for ITER in areas such as fuel clean-up of plasma exhaust gas, qualification of components by long-term testing under a relevant tritium environment, and tritium accountancy based on calorimetry. (author)

67

IC ENGINE SUPERCHARGING AND EXHAUST GAS RECIRCULATION USING JET COMPRESSOR  

Directory of Open Access Journals (Sweden)

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.

Adhimoulame Kalaisselvane

2010-01-01

68

Experimental study on exhaust gas after treatment using limestone  

Directory of Open Access Journals (Sweden)

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

Sakhrieh Ahmad

2013-01-01

69

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

Science.gov (United States)

...exhaust-gas cooling system. 36.47 Section...EVALUATION, AND APPROVAL OF MINING PRODUCTS APPROVAL...exhaust-gas cooling system. (a) The adequacy...establish the cooling performance of the system, the cooling water...

2010-07-01

70

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

Science.gov (United States)

...2010-07-01 false Exhaust gas sampling system; Diesel-cycle...requiring particulate emissions measurements. 86...210-08 Exhaust gas sampling system; Diesel-cycle...requiring particulate emissions measurements. (a...applicability. The exhaust gas sampling system...

2010-07-01

71

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

Science.gov (United States)

...2010-07-01 false Exhaust gas sampling system; Otto-cycle...requiring particulate emission measurements. 86...86.109-94 Exhaust gas sampling system; Otto-cycle...requiring particulate emission measurements. (a)(1) General. The exhaust gas sampling system...

2010-07-01

72

Exhaust gas treatment in testing nuclear rocket engines  

International Nuclear Information System (INIS)

With the exception of the last test series of the Rover program, Nuclear Furnace 1, test-reactor and rocket engine hydrogen gas exhaust generated during the Rover/NERVA program was released directly to the atmosphere, without removal of the associated fission products and other radioactive debris. Current rules for nuclear facilities (DOE Order 5480.6) are far more protective of the general environment; even with the remoteness of the Nevada Test Site, introduction of potentially hazardous quantities of radioactive waste into the atmosphere must be scrupulously avoided. The Rocketdyne treatment concept features a diffuser to provide altitude simulation and pressure recovery, a series of heat exchangers to gradually cool the exhaust gas stream to 100 K, and an activated charcoal bed for adsorption of inert gases. A hydrogen-gas fed ejector provides auxiliary pumping for startup and shutdown of the engine. Supplemental filtration to remove particulates and condensed phases may be added at appropriate locations in the system. The clean hydrogen may be exhausted to the atmosphere and flared, or the gas may be condensed and stored for reuse in testing. The latter approach totally isolates the working gas from the environment

73

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)

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.

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

2014-05-13

74

Flow in non-symmetric gas turbine exhaust ducts  

Science.gov (United States)

An experimental and computational study of non-symmetric single-port gas turbine exhaust ducts has been carried out. The geometry of the exhaust duct incorporates an annular to rectangular transition with a 160° turn. The focus of the study was to determine the effect of inlet conditions and duct geometry on the flow structure and the level of overall pressure losses in the duct flow. As part of this work, the appropriateness of boundary conditions for both experimental and computational studies was investigated. The experimental studies were carried out using a ½-scale cold flow apparatus capable of measuring the flow conditions at the inlet and outlet of the duct. Inlet conditions varied included the level of swirl and circumferential total pressure distribution. Computational fluid dynamic (CFD) studies were carried out using a commercial solver using k - epsilon turbulence modeling and non-equilibrium wall functions. The computational solutions were benchmarked against experimental values, allowing CFD to be used to extend the range of inlet conditions beyond the range that could be obtained experimentally, to those more typical of an engine installation. Results show that inlet conditions have a significant effect on the flow structure in the exhaust duct. Total pressure losses in the exhaust duct increase as the circumferential inlet total pressure distribution becomes more non-uniform. This results in losses measured on a standard cold-flow apparatus under-predicting those that would exist on a duct installed on a gas turbine. However, trends in the geometric variables identified experimentally using cold flow were confirmed computationally with inlet conditions more typical of an exhaust duct mounted on an engine.

Cunningham, Mark H.

75

Exhaust-gas reforming using precious metal catalysts  

International Nuclear Information System (INIS)

Rh-only and Rh bimetallic catalysts have been screened for exhaust-gas reforming, under conditions that mimic the output of an autoignition gasoline engine. Propane has been used as a model fuel, with simulated exhaust-gas providing the co-reactants (O2 and H2O) needed to generate hydrogen. Based on oxygen-conversion as a measure of light-off, Pt-Rh on ceria-zirconia shows the highest activity. In the presence of SO2, adsorbed sulphur species do not inhibit the oxidation reactions that induce light-off, but suppress the major pathway to hydrogen (steam reforming). By excluding platinum and using silica-enriched alumina as the underlying support, light-off is delayed, but the steam reforming reaction becomes much more insensitive to the presence of sulphur. The Pt-Rh catalyst is most suited to exhaust-gas reforming systems in which the engine runs on a sulphur-free fuel, whereas the Rh-only catalyst is the better choice when the fuel is conventional gasoline. (author)

76

Rayleigh scattering in supersonic high-temperature exhaust plumes  

Energy Technology Data Exchange (ETDEWEB)

A supersonic exhaust plume test rig and a Rayleigh scattering system were developed. Molecular number densities in the supersonic high-temperature exhaust plume with and without an annular base flow were investigated. The physical meaning of the inferred mean temperature from the number density measurement in turbulent flows is clarified. For both flows, the potential core extends up to about six nozzle diameters, and self-similarity of the radial density distributions is observed at downstream sections Z/d=10-50. The recovery of the flow density deficit (or the decay of temperature) with the annular flow is faster than that without the annular flow at upstream sections Z/d {<=} 10. (orig.)

Jiang, L.Y. [Institute for Aerospace Research, National Research Council Canada, Ottawa (Canada); Sislian, J.P. [Institute for Aerospace Studies, University of Toronto, ON (Canada)

2002-04-01

77

An intelligent instrument for measuring exhaust temperature of marine engine  

Science.gov (United States)

Exhaust temperature of the marine engine is commonly measured through thermocouple. Measure deviation will occur after using the thermocouple for some time due to nonlinearity of thermocouple itself, high temperature and chemical corrosion of measure point. Frequent replacement of thermocouple will increase the operating cost. This paper designs a new intelligent instrument for solving the above-mentioned problems of the marine engine temperature measurement, which combines the conventional thermocouple temperature measurement technology and SCM(single chip microcomputer). The reading of the thermocouple is simple and precise and the calibration can be made automatically and manually.

Ma, Nan-Qi; Su, Hua; Liu, Jun

2006-12-01

78

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Kauranen, Pertti; Elonen, Tuomo; Wikstro?m, Lisa; Heikkinen, Jorma; Laurikko, Juhani

2009-01-01

79

Plasma Assisted Catalyst for NOx Remediation from Lean Gas Exhaust  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A non-thermal plasma (NTP) reactor was coupled with a three-function catalyst in order to verify the nature of the effect of the plasma on the catalytic process. A mixture of NO/O2/hydrocarbons in N2 was used as a lean model exhaust gas composition. The plasma was found to perform two of the three functions defined in the catalysis model when coupling the plasma reactor to the catalytic deNOx: NO oxidation to NO2 and hydrocarbon activation through the partial oxidation to aldehyde and/or alco...

Khacef, Ahmed; Da Costa, Patrick; Dje?ga-mariadassou, Ge?rald

2013-01-01

80

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

Directory of Open Access Journals (Sweden)

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.

Kartika K. Hendratna

2010-01-01

 
 
 
 
81

Intensity of corrosion processes in exhaust gas boilers at burning water-fuel emulsion  

Directory of Open Access Journals (Sweden)

Full Text Available Approximation dependences of specific rates of low-temperature sulfur corrosion and pollution intensity under the influence of the main parameters characterizing these processes are presented. Statistical processing of the research results that displayed the primary influence on decrease in metal sulfur and water content of water fuel emulsion is conducted. The dependences of low-temperature sulfur corrosion rate on the wall temperature for 100 and 1000 hours at burning standard fuel and water-fuel emulsion are received. Reliability of data transfer obtained at experimental facility on consideration of these processes in real exhaust gas boilers installed after internal-combustion engine is confirmed.

Goryachkin Vladimir Yurievich

2013-10-01

82

Cfd and Analytical Analysis of Exhaust System of a Gas Turbine Used in a Ship  

Science.gov (United States)

In this study, exhaust system of the gas turbine of a ship with CODOG (Combined Diesel Or Gas-turbine) system is analyzed both analytically and numerically. The results obtained from these two different methods are then compared. The flow and heat transfer analysis of the exhaust system is done using a full scale two-dimensional (2-D) model and in the simulation velocity vectors, pressure and temperature fields are obtained. The gas turbine exhaust system velocity is 40 m/s, especially just after the inlet. For the mathematical model, time-averaged, steady-state, mean flow equations of continuity, momentum and energy equations can be written in Cartesian tensor notation. In commercially available computational fluid dynamics (CFD) code FLUENT 6.2, the governing equations are discretized using second order upwind interpolation scheme, and the discretized equations are solved using SIMPLEC algorithm. The Standard k-? turbulence model is used for the turbulence closure. The boundary layer meshes are applied for obtaining more precise results, especially in the vicinity of walls. It is shown that the CFD calculations can be applied to such a practical problem to improve analysis performance. In conclusion, velocity vectors, temperature and pressure fields and pressure losses calculated CFD and analytical calculations are compared with numerical results.

Bayraktar, Seyfettin; Safa, Aykut; Yilmaz, Tamer

2007-09-01

83

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

Science.gov (United States)

...requirements listed for the exhaust gas PDP-CVS (§ 86.109-94...requirements listed for the exhaust gas EFC sample system (§ 86...air and exhaust are well mixed. (ii) Heated and insulated...5) The dilute exhaust gas flowing in the THC sample...

2010-07-01

84

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

85

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

Science.gov (United States)

...sample is collected, a heat exchanger is required. (iii) If a heat exchanger is used, the gas mixture temperature...vehicles, the transfer of heat from the vehicle exhaust...of electrically conductive material which does not react...

2010-07-01

86

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

Science.gov (United States)

...sample is collected, a heat exchanger is required. (iii) If a heat exchanger is used, the gas mixture temperature...vehicles, the transfer of heat from the vehicle exhaust...if insulated) of smooth stainless steel tubing from the...

2010-07-01

87

Engine exhaust particulate and gas phase contributions to vascular toxicity.  

Science.gov (United States)

Cardiovascular health effects of near-roadway pollution appear more substantial than other sources of air pollution. The underlying cause of this phenomenon may simply be concentration-related, but the possibility remains that gases and particulate matter (PM) may physically interact and further enhance systemic vascular toxicity. To test this, we utilized a common hypercholesterolemic mouse model (Apolipoprotein E-null) exposed to mixed vehicle emission (MVE; combined gasoline and diesel exhausts) for 6?h/d?×?50?d, with additional permutations of removing PM by filtration and also removing gaseous species from PM by denudation. Several vascular bioassays, including matrix metalloproteinase-9 protein, 3-nitrotyrosine and plasma-induced vasodilatory impairments, highlighted that the whole emissions, containing both particulate and gaseous components, was collectively more potent than MVE-derived PM or gas mixtures, alone. Thus, we conclude that inhalation of fresh whole emissions induce greater systemic vascular toxicity than either the particulate or gas phase alone. These findings lend credence to the hypothesis that the near-roadway environment may have a more focused public health impact due to gas-particle interactions. PMID:24730681

Campen, Matthew; Robertson, Sarah; Lund, Amie; Lucero, Joann; McDonald, Jacob

2014-05-01

88

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)

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.

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

2002-01-01

89

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

Science.gov (United States)

...methanol consists of a gas chromatograph (GC...ionization detector. The analysis for formaldehyde is...derivatives using ultraviolet (UV) detection. The exhaust gas analytical system shall...to nitric oxide before analysis. Other types of...

2010-07-01

90

Removal of methane from compressed natural gas fueled vehicle exhaust  

International Nuclear Information System (INIS)

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

91

Comments on the low frequency radiation impedance of a duct exhausting a hot gas.  

Science.gov (United States)

The influence of convection and temperature on the radiation impedance of an open duct termination exhausting a hot gas is commonly described by a complex theory. A simplified analytical expression is proposed for low frequencies. Both models assume a free jet with uniform velocity bounded by infinitely thin shear layers. The convective velocity that should be assumed when applying these models to a non-uniform outflow is uncertain. A simplified version of the so-called Vortex Sound Theory demonstrates that the convective velocity one should assume is lower than the jet centerline velocity. PMID:25096151

Hirschberg, Avraham; Hoeijmakers, Maarten

2014-08-01

92

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)

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

Segura Ozuna, Victor Octavio

2004-11-15

93

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

International Nuclear Information System (INIS)

Two optical approaches, comprising and contracting both the fluorescence decay lifetime and the fibre Bragg grating (FBG) methods, were developed and evaluated for temperature monitoring of exhaust gases for use on a vehicle engine. The FBGs used in the system were written into specially designed Bi-Ge co-doped photosensitive fibres, to enable them to sustain high temperatures to over 8000C, which is far beyond that of FBGs written into most commercial photosensitive fibres. The sensors were subjected to a range of vibration tests, as a part of an optical exhaust monitoring network under development, and results from the test carried out are reported

94

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Adzuieen Nordin; Mohd Amin Abd Majid

2013-01-01

95

NOVEL GAS SENSORS FOR HIGH-TEMPERATURE FOSSIL FUEL APPLICATIONS  

Energy Technology Data Exchange (ETDEWEB)

SRI is developing ceramic-based microsensors for detection of exhaust gases such as NO, NO{sub 2}, and CO in advanced combustion and gasification systems. The sensors detect the electrochemical activity of the exhaust gas species on catalytic electrodes and are designed to operate at high temperatures, elevated pressures, and corrosive environments typical of large power generation exhausts. Under this research project we are developing sensors for multiple gas detection in a single package along with data acquisition and control software and hardware. The sensor package can be easily integrated into online monitoring systems for active emission control. This report details the research activities performed from October 2003 to April 2004.

Palitha Jayaweera

2004-05-01

96

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Baleshwar Kumar Singh,; Dr. Nitin Shrivastava

2014-01-01

97

Optical system for CO and NO gas detection in the exhaust manifold of combustion engines  

International Nuclear Information System (INIS)

The experimental characterization of an innovative optical system for detection of carbon monoxide (CO) and nitride oxide (NO) in the exhaust manifold of otto and diesel engines is reported. A photodetector based on gallium nitride (GaN) and an UV light source are integrated in a chamber of analysis and form the detection system. The UV light source, consisting of a spark produced by an arc discharge, induces electronic transitions in the gas molecules flowing between the light source and the GaN photodetector. The transitions modify the fraction of light in the UV spectral region which is detected by the GaN photodetector, as a function of the species concentration. By means of its structural properties, gallium nitride (GaN) allows to operate at high temperature and high speed and to work in situ in the exhaust manifold of combustion engines at temperatures as high as 600 oC, at which the deposited organic residuals on the detector can be oxidized. This assures a clear surface necessary for a real time optical measurement of the species concentration to be used for a closed loop control of the fuel injection process. The system was applied to the detection of CO and NO with concentration between 0% and 2% in a buffer of pure nitrogen gas, showing an increase in the measured photocurrent as a function of the above gases

98

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

Science.gov (United States)

...exhaust gas dilution function at the engine exhaust...The CO and CO2 analytical system requires... (7) The NOX analytical system requires a continuously...and coordinate the functions of the component...Other sampling and/or analytical systems may be...

2010-07-01

99

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

Science.gov (United States)

...the vehicle exhaust pipe; or (iv) Partial dilution of the exhaust gas prior to entering...at any point in the dilution tunnel. Direct sampling of the particulate material may...and back-up filters shall not be in contact with each other. (iv) It is...

2010-07-01

100

Turbine gas temperature measurement and control system  

Science.gov (United States)

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)

Webb, W. L.

1973-01-01

 
 
 
 
101

Exhaust purification with on-board ammonia production  

Energy Technology Data Exchange (ETDEWEB)

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

Robel, Wade J. (Peoria, IL); Driscoll, James Joshua (Dunlap, IL); Coleman, Gerald N. (Helpston, GB)

2010-10-12

102

30 CFR 36.26 - Composition of exhaust gas.  

Science.gov (United States)

...MINING PRODUCTS APPROVAL REQUIREMENTS FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION EQUIPMENT Construction and Design...liquid-fuel-injection rate shall be such that the exhaust will not contain black smoke and the applicant shall adjust the injection rate...

2010-07-01

103

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

Science.gov (United States)

40 Protection of Environment 20 2010-07-01 2010-07-01 false Exhaust gas and particulate sampling... ) Small enough in diameter to cause turbulent flow (Reynolds Number greater than 4000) and of sufficient length...

2010-07-01

104

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

Science.gov (United States)

40 Protection of Environment 19 2010-07-01 2010-07-01 false Exhaust gas sampling and analytical...A) Small enough in diameter to cause turbulent flow (Reynolds Number greater than 4000) and of sufficient length...

2010-07-01

105

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

Science.gov (United States)

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.

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

2012-05-15

106

Measurement of exhaust gas recirculation rate by laser-induced fluorescence in engine  

International Nuclear Information System (INIS)

The objective of this study is to measure by planar laser-induced fluorescence the exhaust gas recirculation (EGR) rate in the combustion chamber of an optical engine to quantify the stratification phenomena used in the new combustion strategy. From the results obtained in a high pressure–high temperature (HP–HT) facility, the tracer chosen for this aim is 3-pentanone. This paper presents a quantitative measurement of the EGR rate in the engine and a post-processing model with a correction and calibration procedure by considering the influence of temperature and pressure on the absorption cross-section and the 3-pentanone fluorescence quantum yield from the results established in the HP–HT facility. The stratification phenomena are quantified by using 3-pentanone fluorescence for two different configurations of EGR introduction in the engine. The local fluorescence measurements in the HP–HT facility are also compared with planar fluorescence measurements in the optical engine

107

Use of exhaust gas as sweep flow to enhance air separation membrane performance  

Science.gov (United States)

An intake air separation system for an internal combustion engine is provided with purge gas or sweep flow on the permeate side of separation membranes in the air separation device. Exhaust gas from the engine is used as a purge gas flow, to increase oxygen flux in the separation device without increasing the nitrogen flux.

Dutart, Charles H. (Washington, IL); Choi, Cathy Y. (Morton, IL)

2003-01-01

108

30 CFR 36.25 - Engine exhaust system.  

Science.gov (United States)

...at the point of discharge from the cooling...temperature of the exhaust gas exceeds 185 °F. at the point of discharge from the cooling...passing the exhaust gas through water...a gage or sampling tube is...

2010-07-01

109

Stratification of exhaust gas in SI-engines; Schichtung von rueckgefuehrtem Abgas im Viertakt-Ottomotor  

Energy Technology Data Exchange (ETDEWEB)

At SI engines throttle losses are rising with the decrease of the load due to the throttle control, which results in poor efficiency at part load. One way to reduce throttle losses is the recirculation of exhaust gas. In conventional systems the recirculated exhaust gas is mixed homogeneous with the fresh mixture, but due to ignition problems the residual gas fraction is limited in such systems. To increase the maximum residual gas fraction the exhaust gas was recirculated internal. A single cylinder SI engine was equipped with variable valve timing and an extra valve to induct exhaust gas directly into the combustion chamber. By means of suitable valve timing strategies a stratification of exhaust gas and fresh mixture was generated, as the visualisation of the fuel distribution with a laser-optical measurement technique has shown. The results present the potentialities of exhaust gas recirculation to reduce fuel consumption by decreasing throttle losses on SI engines at part load. The stoichiometric engine condition allows to use the three-way catalyst technology for best exhaust gas aftertreatment. (orig.) [Deutsch] Beim Ottomotor treten aufgrund der Drosselregelung mit sinkender Last zunehmend Ladungswechselverluste auf, die zu relativ schlechten Teillastwirkungsgraden fuehren. Eine Moeglichkeit zur Reduzierung dieser Ladungswechselverluste besteht im Einsatz der Abgasrueckfuehrung. Bei konventionellen Systemen wird das rueckgefuehrte Abgas homogen der Ansaugluft zugemischt, wobei der maximale Restgasanteil aufgrund auftretender Entflammungsprobleme begrenzt ist. Eine deutliche Erhoehung des erreichbaren Abgasanteils konnte durch innere Abgasrueckfuehrung realisiert werden. Dazu wurde ein Einzylinder-Forschungsmotor mit einem variablen Ventiltrieb und einem zusaetzlichen Ventil zur direkten Rueckfuehrung von Abgas in den Brennraum ausgeruestet. Durch geeignete Ventil-Steuerstrategien konnten Schichtungen von Abgas und Frischgemisch im Brennraum erreicht werden, wie die Visualisierung der Kraftstoffverteilung mittels laseroptischer Untersuchungen gezeigt hat. Die Ergebnisse stellen Moeglichkeiten der Abgasrueckfuehrung zur Kraftstoffverbrauchsreduzierung durch Verringerung der Ladungswechselverluste von Ottomotoren im Teillastbetrieb vor. Der stoechiometrische Motorbetrieb erlaubt weiterhin die uneingeschraenkte Nutzung des Drei-Wege-Katalysators zur Abgasnachbehandlung. (orig.)

Spiegel, L.; Haug, M.; Meyer, J.; Andrian, S. v.

1996-07-01

110

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

Science.gov (United States)

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.

Orosa, John

2014-03-11

111

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2013-03-01

112

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)

113

Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators.  

Science.gov (United States)

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 generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results. PMID:22442670

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

2012-01-01

114

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-06-01

115

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

DEFF Research Database (Denmark)

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.

Thomsen, Asser H; Gregersen, Markil

2006-01-01

116

Numerical analysis of exhaust gas flow during the gas exchange process and the design optimization; Haiki manihorudonai no hiteijo nagare kaiseki gijutsu to sono oyo  

Energy Technology Data Exchange (ETDEWEB)

A simulation method was developed to estimate exhaust gas flow during the gas exchange process. In this simulation, one dimensional in-cylinder gas flow calculation and three dimensional exhaust gas flow calculation were combined. Gas flow inside the exhaust manifold catalyst during gas exchange was agreed in experiments. A simulation method was applied to select oxygen sensor location. A prediction of the oxygen sensor sensitivity of each cylinder gas was presented. The possibility of selecting oxygen sensor location in the exhaust manifold using calculation was proved. 5 refs., 10 figs., 1 tab.

Yoshizawa, K.; Takeyama, S.; Sakai, E.; Tanzawa, K. [Nissan Motor Co. Ltd., Tokyo (Japan)

1997-10-01

117

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

Directory of Open Access Journals (Sweden)

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.

Adzuieen Nordin

2013-12-01

118

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

Science.gov (United States)

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.

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

119

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

Science.gov (United States)

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

Nagorny, S; Francke, W

2005-01-01

120

Reaction kinetics and reactor modelling in the design of catalytic reactors for automotive exhaust gas abatement  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract The tightening environmental legislation and technological development in automotive engineering form a challenge in reactor design of catalytic reactors for automotive exhaust gas abatement. The catalytic reactor is the heart of the exhaust aftertreatment processes, but it can be seen also just as one subsidiary part of vehicles. The aim of this work is to reveal applicable kinetic models to predict behaviour of the particular catalysts and to establish guidelines for modelli...

Ahola, Juha

2009-01-01

 
 
 
 
121

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1991-01-01

122

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

Science.gov (United States)

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

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

1982-01-01

123

Diesel emission reduction using internal exhaust gas recirculation  

Science.gov (United States)

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.

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

2012-01-24

124

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

125

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Science.gov (United States)

... false Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty...1310-2007 Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty...Measurement Using Gas Chromatography...Materials, Fuels, Emissions, and Noise,...

2010-07-01

126

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

DEFF Research Database (Denmark)

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.

Hansen, Jakob Mahler; Blanke, Mogens

2013-01-01

127

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

Science.gov (United States)

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.

Saebea, Dang; Patcharavorachot, Yaneeporn; Arpornwichanop, Amornchai

2012-06-01

128

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

Directory of Open Access Journals (Sweden)

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

Snežana D Petkovi?

2010-01-01

129

40 CFR 86.1511 - Exhaust gas analysis system.  

Science.gov (United States)

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test...Concentration Applicable analyzer CO2 14 percent CO C3...

2010-07-01

130

40 CFR 86.1509 - Exhaust gas sampling system.  

Science.gov (United States)

...Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines, New Otto-Cycle Light-Duty Trucks, and New...Petroleum Gas-Fueled Diesel-Cycle Light-Duty Trucks; Idle Test...additional raw carbon dioxide (CO2 ) analyzer as...

2010-07-01

131

Technologies for increasing CO2 concentration in exhaust gas from natural gas-fired power production with post-combustion, amine-based CO2 capture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Enhanced CO2 concentration in exhaust gas is regarded as a potentially effective method to reduce thehigh electrical efficiency penalty caused by CO2 chemical absorption in post-combustion capturesystems. The present work evaluates the effect of increasing CO2 concentration in the exhaust gas of gasturbine based power plant by four different methods: exhaust gas recirculation (EGR), humidification(EvGT), supplementary firing (SFC) and external firing (EFC). Efforts have been focused on the im...

Li, Hailong; Ditaranto, M.; Berstad, D.

2011-01-01

132

A method for a numeric prediction of gas turbine exhaust ducts out door noise  

Energy Technology Data Exchange (ETDEWEB)

When Electricite de France (EDF) ordered a 216 MWe gas turbine in 1986, the preliminary evaluation of the noise radiated by the exhaust duct had been a difficult problem. Therefore, EDF has developed an acoustic model of the exhaust duct of the turbine in order to compare the solutions proposed by different builders and to test the influence of the exhaust duct geometry modification on the environmental sound level. This model is based on bidimensional modelling of the exhaust duct and is developed in three main steps: a computation of the flow in the exhaust duct using a k - {epsilon} code. This computation provides the basic data needed for modeling the noise generated downstream the silencers and the convected field for the computation of sound propagation; a computation of the noise generated by the flow turbulence downstream the silencers. It is based on the Ribner modelling of noise radiated by turbulent subsonic free jets and uses the results of the flow computation. In this way, we compute the turbulent noise levels and assume that the total noise levels throughout the duct exit is the sum of the turbulent noise and of the turbine noise; a computation of sound propagation in the exhaust duct. This computation takes into account the flow and the attenuation of sound due to the silencers. In a first stage, it is validated by measurements taken when the machine is out of operating condition. The second stage provides the turbine noise levels throughout the tack exit. (author) 8 refs.

Guivarch, M.

1995-10-01

133

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

Energy Technology Data Exchange (ETDEWEB)

This study investigated high performance liquid chromatography (HPLC) to identify and measure aldehydes from automobile exhaust gas. Four aldehydes: formaldehyde (HCHO), acetaldehyde (CH{sub 3}CHO), acrolein (H{sub 2}C=CHCHO) and propionaldehyde (CH{sub 3}CH{sub 2}CHO) and one ketone, acetone (CH{sub 3}){sub 2}CO 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.

Roy, Murari Mohon [Department of Mechanical Engineering, Rajshahi University of Engineering and Technology (RUET), Rajshahi 6204 (Bangladesh)], E-mail: mmroy5767@yahoo.com

2008-05-15

134

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

135

40 CFR 86.111-94 - Exhaust gas analytical system.  

Science.gov (United States)

...high pressure liquid chromatography (HPLC) of...conditioning column containing CaSO4...conditioning column may be deleted...Measurement Using Gas Chromatography,” December...high-pressure liquid chromatography (HPLC)...

2010-07-01

136

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

137

Reformulation of engine gasoline to reduce exhaust emissions in Finnish conditions. Effect of gasoline aromatics, olefins and T90 temperature on exhaust emissions  

International Nuclear Information System (INIS)

The research work focused on the effects of gasoline composition, i.e. aromatics and olefin contents and 90 % point of distillation, on exhaust emissions. The experimental part comprised exhaust gas measurements for 13 catalyst cars at +22 deg C and for one non-catalyst car at +22 deg C according to FTP75 driving cycle. Regulated emissions (THC, CO and NOx), non-regulated emissions (hydrocarbons and aldehydes), carbon dioxide and fuel consumption were measured. The high aromatics contents of eight test fuels were about 40 vol% and the low ones about 15 vol%, the high olefin contents were about 15 vol% and the low ones about 2 vol%, and the high T90 temperatures about +170 deg C and the low ones +145 deg C. The results were treated in two ways: effects of each single change in characteristics, and those of simultaneous changes in all fuel characteristics studied. The lowest CO and THC emissions for the catalyst cars at +22 deg C were obtained by reducing the aromatics content and the T90 temperature of the fuel, while the reduction of the olefin content increased respective emissions. The NOx emission increased when the aromatics content and T90 temperature were reduced, and decreased slightly when the olefin content was reduced. The CO2 emission and the fuel consumption (kg/100 km) were affected, i.e. reduced, only by a reduction in the aromatics content. However, the fuel consumption in volume units (1/100 kg) increased. The results a units (1/100 kg) increased. The results at -7 deg C for THC and NOx emissions were along the same lines as at +22 deg C, except for the CO emission, which decreased when the olefin content was reduced and increased when the T90 temperature was lowered

138

Exhaust gas emission from ships in Norwegian coastal waters  

International Nuclear Information System (INIS)

For the following vessel categories bunker consumption and emission of greenhouse gases and SO2 has been calculated: Norwegian coastal trade, domestic ferries, fishing vessels (Norwegian), Norwegian military vessels, inter-coastal ferries, import and export, ships iron-ore from Narvik and Soviet vessels in transit. The carbon emission (CO2 as carbon) within 12 nautical miles has been calculated to 0.621 MtC (Mega ton carbon) and to 1.0 MtC within the economic zone for these vessel categories. The calculated ''inland waterways'' bunker consumption in this study deviates from the Central Bureau of Statistics of Norway and OECD/IEA figures by up to 25%. This large deviation supports the need for a uniform method to calculate ''inland waterways'' bunker consumption. Scenarios for the emission outlook for the years 1995, 2000 and 2005 are discussed and calculated. With 1988 as present level it is possible, according to these scenarios, to reduce the emission of NOx by close to 40% and SO2 by 85%. Reduction of greenhouse- and SO2 components in the exhaust gases from ships is today technically possible, but the demand for further research and development is significant. Compared with land-based low-emission technologies, the offshore technologies are years behind. 21 refs., 9 figs., 9 tabs

139

Catalytic treatment of exhaust gas of small-volume, two-stroke internal combustion engines. Katalytische Abgasnachbehandlung an kleinvolumigen Zweitaktottomotoren  

Energy Technology Data Exchange (ETDEWEB)

Environmental pollution due to exhaust emissions of small-volume, two-stroke internal combustion engines (e.g. in small cars and motorbikes) is a problem that cannot be neglected, especially in view of the high emissions of uncombusted hydrocarbons. Apart from improvements in engine design, oxidation catalysts of noble metal are a means of reducing emissions in these groups of vehicles. After optimisation of a two-bed catalyst system, CO and HC emissions were much lower than the limiting values states in ECE specification No. 47 and lower than the values measured in comparable four-stroke engines. The service life of catalysts in European climate was studied and found to be satisfactory in view of the annual mileage of the vehicle categories investigated. Ae the same time, exhaust gas opacity was found to be improved. The author further attempted to determine the reaction mechanisms of CO and HC oxidation at the given exhaust gas composition and to find out about the temperature conditions inside the catalyst.

Mikulic, L.

1982-01-01

140

Characterization and control of exhaust gas from diesel engine firing coal-water mixture  

Energy Technology Data Exchange (ETDEWEB)

Exhaust from the GE-TS single cylinder diesel engine, fitted with hardened metal, and diamond-tipped metal fuel injection nozzles, and firing coal-water mixture (CWM) has been characterized with respect to gas composition, particulate size distribution, and particulate filtration characteristics. The measured flue gas compositions are roughly in keeping with results from combustion calculations. The time variations of the hydrocarbon, CO, and NO[sub x] concentrations are also understood in terms of known reaction mechanisms.

Samuel, E.A.; Gal, E.; Mengel, M.; Arnold, M.

1990-03-01

 
 
 
 
141

Characterization and control of exhaust gas from diesel engine firing coal-water mixture  

Energy Technology Data Exchange (ETDEWEB)

Exhaust from the GE-TS single cylinder diesel engine, fitted with hardened metal, and diamond-tipped metal fuel injection nozzles, and firing coal-water mixture (CWM) has been characterized with respect to gas composition, particulate size distribution, and particulate filtration characteristics. The measured flue gas compositions are roughly in keeping with results from combustion calculations. The time variations of the hydrocarbon, CO, and NO{sub x} concentrations are also understood in terms of known reaction mechanisms.

Samuel, E.A.; Gal, E.; Mengel, M.; Arnold, M.

1990-03-01

142

40 CFR 86.111-94 - Exhaust gas analytical system.  

Science.gov (United States)

...HIGHWAY VEHICLES AND ENGINES Emission Regulations...Otto-Cycle Complete Heavy-Duty Vehicles; Test...methanol-fueled diesel-cycle vehicles...petroleum gas-fueled diesel vehicles, the sample...methanol-fueled diesel-cycle vehicles, the...Program, Volume 1: Materials, Fuels,...

2010-07-01

143

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

Directory of Open Access Journals (Sweden)

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.

Baleshwar Kumar Singh,

2014-11-01

144

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

Science.gov (United States)

...average non-methane organic gas exhaust emission standards for light-duty...for the Voluntary National Low Emission Vehicle Program for Light-Duty...average non-methane organic gas exhaust emission standards for light-duty...

2010-07-01

145

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.

146

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

Energy Technology Data Exchange (ETDEWEB)

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.

Orosa, John; Montgomery, Matthew

2014-02-11

147

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

148

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

Directory of Open Access Journals (Sweden)

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.

Hou Xuejun

2012-06-01

149

Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; Motoren- und Abgasnachbehandlungskonzepte fuer schwere Nutzfahrzeuge in der Zukunft  

Energy Technology Data Exchange (ETDEWEB)

To comply with the strict exhaust-gas emission limits required by US 2010 and Euro VI the level of oxides of nitrogen must be brought down to the lowest possible level inside the engine so that downstream of the engine not too much space will be required for the necessary exhaust-gas cleaning. The new WHDC cycle has a decisive influence on Euro VI, as it is based on very low engine speeds and low loads compared to the ESC and ETC cycles in use today. As it will probably be possible to achieve the necessary untreated NO{sub x} values only with two-stage turbocharging combined with high exhaust-gas recirculation rates, the exhaust gas temperature level will fall even further. If the necessary particulate trap is not to be overloaded with soot the highest possible injection pressure - above 2200 bar - is necessary. Depending on where the PM trap is located an active regeneration system for the filter will be necessary always or only in exceptional cases. In the same way the SCR coating that can be used will depend on the location in the exhaust-gas line and on the use of an active filter regeneration system. Full catalytic converters probably have no chance of survival. The space required for the combined system ought not to be larger than exhaust-gas cleaning systems currently in use, which - above all taking the OBD (on-board diagnosis) regulations into account - constitutes the greatest challenge to the system. Selection of the best materials for the filters and SCR coating will still require some development time. (orig.)

Emmerling, G.; Doering, A.; Walde, F. [MAN Nutzfahrzeuge AG, Nuernberg (Germany)

2008-07-01

150

Electron beam degradation of simulated toluene-containing exhaust gas  

International Nuclear Information System (INIS)

With toluene as an example, experimental investigation on VOCs treatment by electron beam irradiation was carried out. The system uses 0.8 MeV electron beams to irradiate simulated toluene-containing gases to 5kGy-40kGy for investigatiing effects of initial concentration, absorbed dose, humidity on toluene removal rate. The toluene removal rate increased with absorbed dose. With 0.5-l.2Nm3/h of the gas flow at an initial toluene concentration of 1600mg/Nm3, the toluene removal rate was 46.5% at 10kGy and 72.2% at 40kGy. And increasing humidity increased the toluene removal rate, too. Qualitative analysis on by-products of the toluene degradation was made by means of Gas Chromatogram-Mass Spectrometer (GC/MS) and Chromatography of Ions (IC). It was found that the by-products consist of mainly benzaldehyde and formic acid, plus a little benzoic acid, benzyl alcohol, methyl pyridine, nitrotoluene, o-cresol, phenol and benzoin ethyl etherl. Mechanisms of the E-beam toluene removal, i.e. the contributions of OH free radicals and O2 to the oxidation of toluene, were discussed. (authors)

151

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.

152

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

DEFF Research Database (Denmark)

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

Lieke, Kirsten Inga; Rosenorn, Thomas

2013-01-01

153

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

DEFF Research Database (Denmark)

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).

Lieke, Kirsten Inga; RosenØrn, Thomas

2013-01-01

154

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Hou Xuejun; Gao Deli

2012-01-01

155

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

156

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.)

157

Development of a metal hydride refrigeration system as an exhaust gas-driven automobile air conditioner  

Energy Technology Data Exchange (ETDEWEB)

Aiming at developing exhaust gas-driven automobile air conditioners, two types of systems varying in heat carriers were preliminarily designed. A new hydride pair LaNi{sub 4.61}Mn{sub 0.26}Al{sub 0.13}/La{sub 0.6}Y{sub 0.4}Ni{sub 4.8}Mn{sub 0.2} was developed working at 120-200 C/20-50 C/-10-0 C. P-C isotherms and reaction kinetics were tested. Reaction enthalpy, entropy and theoretical cycling coefficient of performance (COP) were deducted from Van't-Hoff diagram. Test results showed that the hydride pair has flat plateau slopes, fast reaction dynamics and small hystereses; the reaction enthalpy of the refrigeration hydride is -27.1 kJ/mol H{sub 2} and system theoretical COP is 0.711. Mean particle sizes during cycles were verified to be an intrinsic property affected by constitution, heat treatment and cycle numbers rather than initial grain sizes. Based on this work pair, cylindrical reactors were designed and a function proving metal hydride intermittent refrigeration system was constructed with heat conducting oil as heat source and water as heat sink. The reactor equivalent thermal conductivity is merely 1.3 W/(m K), which still has not meet practical requirement. Intermittent refrigeration cycles were achieved and the average cooling power is 84.6 W at 150 C/30 C/0 C with COP being 0.26. The regulations of cycling performance and minimum refrigeration temperature (MRT) were determined by altering heat source temperature. Results showed that cooling power and system COP increase while MRT decreases with the growth of heat source temperature. This study develops a new hydride pair and confirms its application in automobile refrigeration systems, while their heat transfer properties still need to be improved for better performance. (author)

Qin, Feng; Chen, Jiangping; Chen, Zhijiu [Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiaotong University, Shanghai 200030 (China); Lu, Manqi; Yang, Ke [Engineering Center, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, Liaoning Province 110016 (China); Zhou, Yimin [Research Center, Zhejiang Yinlun Machinery Co. Ltd., Tiantai County, Zhejiang Province 317200 (China)

2007-10-15

158

Modelling for Control of Exhaust Gas Recirculation on Large Diesel Engines  

DEFF Research Database (Denmark)

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.

Hansen, Jakob Mahler; Zander, Claes-Göran

2013-01-01

159

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

Science.gov (United States)

...Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...emissions in the exhaust of either gasoline-fueled, natural gas-fueled...analysis without significant impact on the volume of dilute exhaust...analysis without significant impact on the volume of dilute...

2010-07-01

160

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

Energy Technology Data Exchange (ETDEWEB)

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)

NONE

2008-12-11

 
 
 
 
161

The effect of piston bowl temperature on diesel exhaust emissions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

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

2005-01-01

162

Poisoning of automotive exhaust gas catalyst components : the role of phosphorus in the poisoning phenomena  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract 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 proced...

Kro?ger, Virpi

2007-01-01

163

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Charles, M.; Agbomadzi, S. P.

2010-01-01

164

The Impact of Temperature Effect on Exhaust Manifold Thermal Modal Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available The impact of temperature effect on exhaust manifold modal analysis is analyzed in this study. Firstly, the temperature field is mapped from the CFD software and then heat conduction process is analyzed in FEM software with the temperature field boundary conditions. At last the modal analysis that considers temperature effect is done. The frequency and vibration mode between cold modal and thermal modal’s are compared. The result shows that temperature has a great influence on the manifold mode and it is very valuable to product design.

Bin Zou

2013-08-01

165

Electron beam treatment technology for exhaust gas for preventing acid rain  

International Nuclear Information System (INIS)

Recently, accompanying the increase of the use of fossil fuel, the damage due to acid rain such as withering of trees and extinction of fishes and shells has occurred worldwide, and it has become a serious problem. The sulfur oxides and nitrogen oxides contained in exhaust gas are oxidized by the action of sunbeam to become sulfuric acid and nitric acid mists, which fall in the form of rain. Acid rain is closely related to the use of the coal containing high sulfur, and it hinders the use of coal which is rich energy source. In order to simplify the processing system for boiler exhaust gas and to reduce waste water and wastes, Ebara Corp. developed the dry simultaneous desulfurizing and denitrating technology utilizing electron beam in cooperation with Japan Atomic Energy Research Institute. The flow chart of the system applied to the exhaust gas treatment in a coal-fired thermal power station is shown. The mechanism of desulfurization and denitration, and the features of this system are described. The demonstration plant was constructed in a coal-fired thermal power station in Indianapolis, Indiana, USA, and the trial operation was completed in July, 1987. The test results are reported. (K.I.)

166

Gas-phase polynuclear aromatic hydrocarbons (PAH) in vehicle exhaust: A method for collection and analysis  

International Nuclear Information System (INIS)

Gas-phase polynuclear aromatic hydrocarbons (PAH) are emitted at low levels in vehicle exhaust compared to other hydrocarbon emissions. A method has been developed involving the trapping of gas phase emissions on Tenax, a macrorecticular porous polymer, followed by thermal desorption onto a capillary gas chromatography column. Gas chromatography/mass spectrometry (GC/MS) was used for the chemical analysis. A detection limit of 0.05 ng was achieved for several gas-phase PAH. This high sensitivity enables the speciation and quantitation of gas-phase PAH collected from a dilution tube during standard driving (test) cycles. The method was demonstrated for the analysis of 9 PAH in the exhaust from a 1987 vehicle (with and without catalyst) during the hot start transient phase of the EPA urban dynamometer driving schedule. The PAH measured include naphthalene, 2-methyl- and 1-methylnaphthalene, biphenyl, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. The four most abundant PAH observed are naphthalene, 2-methyl and 1-methylnaphthalene, and biphenyl, in that order

167

Experimental Study on a Novel Low-temperature Automobile Exhaust Thermoelectric Generator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

To further study on Automobile Exhaust Thermoelectric Generator (AETEG), an experiment setup based on low-temperature Thermoelectric Modules (TEMs) of Bi2Te3 materials, cold source of single-column cooling boxes and heat exchanger of herring-bone interior cavity was constructed. The hot source and cold source temperatures with different output powers and rotate speeds of engine were analyzed and the influences of the main operation con...

Rui Quan; Guangyou Yang; Liang Huang

2013-01-01

168

A Gas Chromatograph/Mass Spectrometer System for UltraLow-Emission Combustor Exhaust Studies  

Science.gov (United States)

A gas chromatograph (GC)/mass spectrometer (MS) system that allows the speciation of unburnt hydrocarbons in the combustor exhaust has been developed at the NASA Lewis Research Center. Combustion gas samples are withdrawn through a water-cooled sampling probe which, when not in use, is protected from contamination by a high-pressure nitrogen purge. The sample line and its connecting lines, filters, and valves are all ultraclean and are heated to avoid condensation. The system has resolution to the parts-per-billion (ppb) level.

Brabbs, Theodore A.; Wey, Chowen Chou

1996-01-01

169

Finite-element analysis of turbulent flow in annular exhaust diffusers of gas turbine engines  

Science.gov (United States)

A modified version of the Petrov-Galerkin weighted residual method coupled with a biquadratic finite element of the Lagrangian type was used to develop a finite-element model of the turbulent flow field in the annular exhaust diffuser of a gas turbine engine. The swirling flow field was analyzed with emphasis on the diffuser off-design operation. A comparison of the numerical results with experimental data shows that the model is applicable to moderately separating flows of the kind that are typically associated with the off-design performance of diffusing passages in gas turbines.

Baskharone, E. A.

1991-01-01

170

Environmental policy constraints for acidic exhaust gas scrubber discharges from ships.  

Science.gov (United States)

Increasingly stringent environmental legislation on sulphur oxide emissions from the combustion of fossil fuels onboard ships (International Maritime Organization (IMO) Regulation 14) can be met by either refining the fuel to reduce sulphur content or by scrubbing the exhaust gases. Commonly used open loop marine scrubbers discharge warm acidic exhaust gas wash water into the sea, depressing its pH. The focus on this paper is on the physics and chemistry behind the disposal of acidic discharges in seawater. The IMO Marine Environment Protection Committee (MEPC 59/24/Add.1 Annex 9) requires the wash water to reach a pH greater than 6.5 at a distance of 4m from the point of discharge. We examine the engineering constraints, specifically size and number of ports, to identify the challenges of meeting regulatory compliance. PMID:25284442

Ulpre, H; Eames, I

2014-11-15

171

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

Directory of Open Access Journals (Sweden)

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

Ralf Moos

2010-07-01

172

A GAS TEMPERATURE PROFILE BY INFRARED EMISSION-ABSORPTION SPECTROSCOPY  

Science.gov (United States)

This computer program calculates the temperature profile of a flame or hot gas. Emphasis is on profiles found in jet engine or rocket engine exhaust streams containing water vapor or carbon dioxide as radiating gases. The temperature profile is assumed to be axisymmetric with a functional form controlled by two variable parameters. The parameters are calculated using measurements of gas radiation at two wavelengths in the infrared spectrum. Infrared emission and absorption measurements at two or more wavelengths provide a method of determining a gas temperature profile along a path through the gas by using a radiation source and receiver located outside the gas stream being measured. This permits simplified spectral scanning of a jet or rocket engine exhaust stream with the instrumentation outside the exhaust gas stream. This program provides an iterative-cyclic computation in which an initial assumed temperature profile is altered in shape until the computed emission and absorption agree, within specified limits, with the actual instrument measurements of emission and absorption. Temperature determination by experimental measurements of emission and absorption at two or more wavelengths is also provided by this program. Additionally, the program provides a technique for selecting the wavelengths to be used for determining the temperature profiles prior to the beginning of the experiment. By using this program feature, the experimenter has a higher probability of selecting wavelengths which will result in accurate temperature profile measurements. This program provides the user with a technique for determining whether this program will be sufficiently accurate for his particular application, as well as providing a means of finding the solution. The input to the program consists of four types of data: (1) computer program control constants, (2) measurements of gas radiance and transmittance at selected wavelengths, (3) tabulations from the literature of gas transmission parameters at selected wavelengths, and (4) independently determined or estimated profiles of partial pressures of the gas reaction products. The output consists of error figures for the temperature and partial pressure profiles in tabular form. This program is written in FORTRAN IV for execution on an UNIVAC 1100 series computer with a main memory requirement of 21K of 36 bit words. This program was developed in 1977.

Buchele, D. R.

1994-01-01

173

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

Science.gov (United States)

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

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

2010-01-01

174

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

Science.gov (United States)

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.

Serres, Nicolas (Epinal, FR)

2010-11-09

175

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

Science.gov (United States)

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.

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

2011-12-01

176

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.

177

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1997-12-31

178

Drying with temperature gas mixture  

International Nuclear Information System (INIS)

A chart with coordinates of enthalpy and humidity ratio for moist air, now is exploited to represent the behaviour of mixture 'moist air - high temperature combustion gas products' in the process of drying. The limits of the procedure are discussed. (Author)

179

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

180

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Lebouvier, Alexandre; Fresnet, Franc?ois; Fabry, Fre?de?ric; Boch, Vale?rie; Rohani, Vandad-julien; Cauneau, Franc?ois; Fulcheri, Laurent

2011-01-01

 
 
 
 
181

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2012-01-01

182

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

Science.gov (United States)

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

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

2012-08-01

183

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.

184

Exhaust-gas measurements from NASAs HYMETS arc jet.  

Energy Technology Data Exchange (ETDEWEB)

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.

Miller, Paul Albert

2010-11-01

185

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

Directory of Open Access Journals (Sweden)

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.

Kolyadin Evgeniy Alekseevich

2010-10-01

186

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

DEFF Research Database (Denmark)

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.

Xin, Gao; Andreasen, SØren Juhl

2014-01-01

187

Development of turbocharger for regulation of automotive engine exhaust gas emission. Hai gas kiseiyo sharyoyo kakyuki no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

In response to the requirement of turbochargers for regulation of automotive engine exhaust gas emission, which have high-pressure ratio, wide operation range, and high efficiency, Ishikawajima-Harima Heavy Industries (IHI) has developed a high performance turbocharger with a small-diameter mixed-flow turbine, light weight, and large swallowing capacity. This paper describes the regulation of diesel engine exhaust gas emission and an outline of the new type turbocharger developed. For this new type turbocharger, the mixed-flow turbine with a large flow rate and high efficiency was adopted, and the aluminium die-cast seal strip with a light weight was used. In addition, high-pressure ratio of the compressor was realized by increasing peripheral speed of the compressor impeller, reducing the outlet blade angle of impeller, and increasing impeller blades. For the compressor developed, the maximum efficiency of 80%, the peripheral speed mach number of 1.5, and the maximum pressure ratio of 3.4 were achieved. Furthermore, the performance of mixed-flow turbine with a high specific rate was illustrated. The fabricated mixed-flow turbine provided higher performance than that of the conventional radial flow turbines. 3 refs., 10 figs., 1 tab.

Ikeya, N.; Yamaguchi, H.; Ijichi, N.; Matsuoka, H. (Ishikawajima-Heavy Industries, Co. Ltd., Tokyo (Japan))

1993-09-01

188

Study and optimization of gas sensors based on tin dioxide (SnO2) in automotive exhaust conditions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study is dedicated to the optimization of chemical gas sensors based on resistive type tin dioxide (SnO2) for automotive exhaust application. The sensors were produced by screen-printing technique which allows mass production of robust sensors on alumina substrate. In regards of the automotive application, the sensors were optimized by adding a porous protective layer deposited on the sensing element SnO2. The behaviour of this type of gas sensors was studied depending on gas parameters ...

Valleron, Arthur

2011-01-01

189

A study on exhaust gas emissions from ships in Turkish Straits  

International Nuclear Information System (INIS)

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

190

A study on exhaust gas emissions from ships in Turkish Straits  

Science.gov (United States)

The Turkish Straits, i.e. Istanbul (Bosphorus) and Canakkale (Dardanellen), which connect Black Sea and Aegean Sea, have a continuously increasing maritime traffic. Especially, the maritime traffic on Bosphorus (Istanbul Strait) that connects the continents of Europe and Asia is too complex due to geographical conditions. The maritime traffic in the Turkish Straits includes the ships, which are in use in domestic transport, the transit passing ships with various aims and fishing, sport or strolling ships. In this paper, fuel consumption and exhaust gas emissions NO x, CO, CO 2, VOC, PM exhausted from ships such as transit vessels, which are passing both Bosphorus and Dardanellen, and passenger ships used in domestic transport on the Bosphorus are calculated. In order to do this the general characteristics, the main engine systems, the fuel types, cruising times and speeds of all vessels are taken into consideration. The calculated NO x emissions on the Bosphorus are 2720 t from domestic passenger ships and 4357 t from transit ships. In this case it is clear that the transit ships cause more than half of the total amount of emissions from ships on the Bosphorus. The amount of nitrogen oxide emissions from domestic passenger ships used for public transport in Istanbul Strait is equal to approx. 4% of nitrogen oxide emissions from motor vehicles in Istanbul. Finally, the future emissions from ships in Turkish Straits are discussed.

Kesgin, Ugur; Vardar, Nurten

191

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

192

Automobile exhaust gas as a source of aqueous phase OH radical in the atmosphere and its effects on physiological status of pine trees.  

Science.gov (United States)

Free radical generation potential of automobile exhaust gas was examined by measuring hydroxyl (OH) radical photo-formation rates in exhaust gas-scrubbing water. Effects of automobile exhausts on physiological status of Japanese red pine trees (Pinus densiflora Sieb. et Zucc.) were also investigated to elucidate the mechanism how the free radicals derived from exhaust gas damage higher plants. Gasoline and diesel exhaust gases were scrubbed into pure water. Potential photo-formation rates of OH radical in aqueous phase (normalized to sun light intensity of clear sky midday on May 1 at 34°N) for gasoline and diesel cars were ave. 51 and 107 ? Mh?¹ m?³ of exhaust gas, respectively. Nitrite was a dominant source (ca. 70-90%) of photochemical formation of OH radical in both gasoline and diesel car exhausts. The scrubbed solution of diesel car exhaust gas was sprayed for six times per week to needles of pine tree seedlings in open top chambers. Control, exhaust+mannitol (added as OH radical scavenger), and nitrite+nitrate standard solution (equivalent levels existed in the exhaust gas) were also sprayed. Two months sprays indicated that the sprayed solutions of diesel exhaust and nitrite+nitrate caused a decrease of maximum photosynthetic rate and stomata conductance in pine needles while the control and exhaust+mannitol solution showed no effects on photosynthetic activities of pine needles. These results indicated that OH radicals generated mainly from photolysis of nitrite occurring in the scrubbing solution of exhaust gas are responsible for the decrease of photosynthetic activities of pine needles. PMID:21767866

Sakugawa, Hiroshi; Matsuda, Toshihide; Nakatani, Nobutake

2011-10-01

193

Novel Gas Sensors for High-Temperature Fossil Fuel Applications  

Energy Technology Data Exchange (ETDEWEB)

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

Palitha Jayaweera; Francis Tanzella

2005-03-01

194

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

Energy Technology Data Exchange (ETDEWEB)

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

Sawai, Takeshi; Sawai, Teruko

2000-03-01

195

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

International Nuclear Information System (INIS)

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

196

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)

197

Method and apparatus for separation and recovery of rare gas from reactor exhaust gas  

International Nuclear Information System (INIS)

Object: To reduce the probability of leakage of radioactive rare gases to thereby enhance safety and reduce the running cost and facilitate operation. Structure: A processed gas having been deprived of water and oxygen is subjected to pressure reduction to 10 to several 100 mm Hg by a vacuum pump and then cooled down through heat exchange with helium, hydrogen, nitrogen and like gases. The resultant gas is passed through an adsorber, which is cooled to 80 to 1200K by a freezer for adsorbing Ar, Kr, Xe and like rare gases and part of nitrogen. The adsorber is then heated to liberate the adsorbed gas, and the liberated gas is led to a condenser which is cooled to 60 to 800K, thus causing condensation of only the rare gases. Thereafter, the condenser is heated to liberate the rare gases from it, these gases then being sealed in a separate recovery tank. (Ikeda, J.)

198

Fuel compositions and additive mixtures containing carboxymethoxy propanedioic acid esters for alleviation of exhaust gas catalyst plugging  

Energy Technology Data Exchange (ETDEWEB)

A gasoline is described for an internal combustion engine having a cyclopentadienyl manganese tricarbonyl antiknock compound and a compound to reduce plugging of an exhaust gas catalyst. The general chemical composition of the compound and options for various radicals are discussed.

Gautreaux, M.F.

1975-07-07

199

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

Science.gov (United States)

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

Hannum, Richard W; Zimmerman, Richard H

1945-01-01

200

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

International Nuclear Information System (INIS)

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.

 
 
 
 
201

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

Science.gov (United States)

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.

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

2012-11-01

202

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

Directory of Open Access Journals (Sweden)

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

Somaye Kasharafifard

2014-06-01

203

The kinetic structure of collisionless slow shocks and reconnection exhausts- the effects of strong temperature anisotropy  

Science.gov (United States)

Ion heating by Petschek-reconnection-associated slow shocks is one of the potential heating mechanisms for solar flares and the solar wind (e.g., Tsuneta 1995). But, the structure of these shocks in a collisionless plasma is still an open question. Therefore a detailed study of the kinetic structure of the reconnection exhaust and how ions/electrons are accelerated is necessary. Instead of performing a complete particle-in-cell reconnection simulation, whose simulation domain is strictly limited by the available computational power, a 2-D Riemann problem is designed to study the development and dynamics of the exhaust boundary. Simulations are carried out for varying ratios of normal magnetic field to upstream magnetic field (i.e., propagation angle with respect to the upstream magnetic field). Collisionless slow shocks form and we find a critical temperature anisotropy (i.e., ?=1-(P?-P?)/?0B2))= 0.25 around the sharp front of the downstream rotational waves at oblique propagation angles. An explanation is proposed by looking into anisotropic fluid theory, in particularly the anisotropic Derivative Nonlinear-Schrodinger-Burgers equation, with an intuitive model of an energy closure for an oblique shock with a fair amount of back-streaming ions that escape from the shock downstream region. The anisotropy value of 0.25 (independent of plasma beta and propagation angle) is significant because it is the degeneracy point of slow and intermediate modes, and the marginal stability value of modulational waves. At very oblique propagating angles (i.e.,~80 degree), a firehose-like instability develops in the downstream region, which might link to the proton temperature anisotropy distribution in the solar wind (e.g., S. D. Bale et. al 2009). The temperature anisotropy distributions for slow shocks pairs at 3 different propagation angles. A clear tendency for the downstream anisotropy values to be locked in 0.25 is seen for all cases. The case of angle 83 degree corresponds to the exhaust of fast reconnection (i.e., reconnection rate ~ 0.1), and its center is in the firehose unstable region (i.e., ? < 0 ).

Liu, Y.; Drake, J. F.; Swisdak, M. M.

2010-12-01

204

CO{sub 2} separation from exhaust gas; CO{sub 2} separasjon fra eksosgass  

Energy Technology Data Exchange (ETDEWEB)

When Saga wanted to reduce the CO{sub 2} emissions from Snorre B, cleaning of CO{sub 2} from exhaust gas was one of several options considered. CO{sub 2} cleaning using membrane/amine technology is under development. Saga required that the technology should be qualified and that the yield of the Snorre B project should not be reduced. This presentation discusses qualification of combined membrane/amine technology, environmental issues, economic issues and implementation on the Snorre B platform. Flue gas from the gas turbine is passed to a CO{sub 2} absorption and desorption stage from which the CO{sub 2} is passed on for compression and disposal while the cleaned flue is let out. The membrane is situated between the flue gas and the absorbent liquid. The pores are large enough for the CO{sub 2} to pass through quickly and small enough to prevent the liquid from penetrating into the pores. The packing factor is high, 500 - 1000 m2/m3, there is no formation of froth, ducts or entrainment of the liquid. New technology implies 65 - 70% size reduction of the main equipment and 39 - 40% reduction of the energy consumption. Research on amines brings out new chemicals which imply 80% reduction in the consumption of chemicals and the quantity of special waste produced. If a CO{sub 2} cleaning plant is installed on a LM 2500, the CO{sub 2} emissions can be reduced by 97,200 ton/year given the right operational conditions. Although it was decided in 1998 not to install the module with the CO{sub 2} pilot cleaning plant, Snorre B is still a good environmental project having CO{sub 2} emission within the values set by Miljoesok.

Magelssen, Paul Fr. [Saga Petroleum A/S, Forus (Norway)

1998-07-01

205

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

Directory of Open Access Journals (Sweden)

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.

RANBIR SINGH

2012-03-01

206

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 o...

Laxe?n, Jonas

2012-01-01

207

High temperature gas cooled reactor  

International Nuclear Information System (INIS)

Purpose: To provide a pebble bed type high temperature gas cooled reactor adapted for use of plutonium fuel. Constitution: A fuel sphere filled in a reactor core consists of a central fuel region and an outside graphite moderator region. The fuel region further consists of an inside fuel region made of graphite as base material and coating fuel particles of plutonium oxide in slight amount added thereto, and an outside thin layer fuel region formed outside the inside fuel region with coating fule particles of plutonium oxide in large quantity added thereto. Since the fuel region is thus formed in no uniformity, neutron absorption amount by plutonium 240 is reduced so that the amount of generated neutron in the entire reactor exceeds the absorption amount to enable use of plutonium fuel. (Kamimura, M.)

208

Low-temperature gas from marine shales  

Directory of Open Access Journals (Sweden)

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.

Jarvie Daniel M

2009-02-01

209

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

210

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

211

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

International Nuclear Information System (INIS)

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

212

Model based exhaust gas estimation of a common rail diesel engine  

Energy Technology Data Exchange (ETDEWEB)

In order to improve fuel economy and the emissions of internal combustion engines, it is necessary to model the combustion process as a basis for control. In this paper, behavioural models are adopted as a compromise between accuracy of description and model complexity. The fuel injection and vaporization process is resolved into three zones: fluid droplets, vaporized and combusted fuel. The combustion chamber is divided into areas of burned and unburned gases, separated by the flame front. The chemical model for calculating emissions is based on the two-zone model. The amount of mass, which is transferred from the unburned to the burned zone, is the input for a chemical model based on the equilibrium for the OCH-system (oxygen/carbon/hydrogen). The result is the total quantity of masses in the burned zone. The nitrogen-oxide emissions are calculated by using the advanced Zeldovich-mechanism which uses the reaction-kinetic approach rather than the less accurate chemical equilibrium assumption. The NO{sub x}-Emissions (nitrogen-oxides) can be influenced by changing the exhaust-gas recirculation (EGR) rate. (author)

Torkzadeh, D.D.; Laengst, W.; Kiencke, U. [University of Karlsruhe (Germany). Institute of Industrial Information Technology

2001-07-01

213

Model based exhaust gas estimation of a common rail diesel engine  

Energy Technology Data Exchange (ETDEWEB)

In order to improve fuel economy and the emissions of internal combustion engines, it is necessary to model the combustion process as a basis for control. In this paper, behavioral models are adopted as a compromise between accuracy of description and model complexity. The fuel injection and vaporization process is resolved into three zones: fluid droplets, vaporized and combusted fuel. The combustion chamber is divided into areas of burned and unburned gases, separated by the flame front. The chemical model for calculating emissions is based on the two-zone model. The amount of mass, which is transferred from the unburned to the burned zone, is the input for a chemical model based on the equilibrium for the OCH-system (oxygen/carbon/hydrogen). The result is the total quantity of masses in the burned zone. The nitrogen-oxide emissions are calculated by using the advanced Zeldovich-mechanism which uses the reaction-kinetic approach rather than the less accurate chemical equilibrium assumption. The NOx-emissions (nitrogen-oxides) can be influenced by changing the exhaust-gas recirculation (EGR) rate. (orig.)

Torkzadeh, D.D.; Laengst, W.; Kiencke, U. [Karlsruhe Univ. (T.H.) (Germany). Inst. of Industrial Information Technology

2001-07-01

214

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

Directory of Open Access Journals (Sweden)

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

B. Jothithirumal

2012-09-01

215

Airflow calibration and exhaust pressure/temperature survey of an F404, S/N 215-109, turbofan engine  

Science.gov (United States)

A General Electric F-404 turbofan engine was calibrated for thrust and airflow at the NASA Lewis Propulsion System Laboratory in support of future flight tests of the X-29 aircraft. Tests were conducted with and without augmentation, over a range of flight conditions, including the two design points of the airplane. Data obtained during the altitude tests will be used to correct two independent gross thrust calculation routines which will be installed and operated on the airplane to determine in-flight gross thrust. Corrected airflow data as a function of corrected fan speed collapsed onto a single curve. Similarly, trends were observed and defined for both augmented and dry thrust. Overall agreement between measured data and F-404 Engine Spec Deck data was within 2 percent for airflow and 6 percent for thrust. The results of an uncertainty analysis for thrust and airflow is presented. In addition to the thrust calibration, the exhaust gas boundary layer pressure and temperatures were surveyed at selected condition and engine power levels to obtain data for another NASA F-404 program. Test data for these surveys are presented.

Burns, Maureen E.; Kirchgessner, Thomas A.

1987-01-01

216

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

International Nuclear Information System (INIS)

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

217

Positional Arrangements of Waste Exhaust Gas Ducts of C-Type Balanced Chimney Heating Devices on Building Façades  

Directory of Open Access Journals (Sweden)

Full Text Available In Turkey today, with the increase in availability of natural gas,detached heating devices are being preferred over existingheating devices. Due to the lack of chimneys in existing buildingsin Turkey or the presence of chimneys that fail to conformto standards, the use of C-type balanced chimney devices has increased.C-type balanced chimney devices take the combustionair directly from the outside by a specific air duct as detachedheating equipment, with enclosed combustion chambers anda specific waste gas exhaust duct, and they are ventilated independentlyof the field of equipment. Because of their essentiality,the use of a chimney is not required in these devices;the waste gas is exhausted through walls, windows, doors, orbalconies. The natural gas is a clean fossil fuel that requires nostorage in buildings and is easy to use. However, water vapor,carbon dioxide and nitrogen oxides are produced by the combustionof natural gas. It is widely known that high concentrationsof these products can have some adverse effects onhumans such as dizziness, headaches and nausea. As a result,the waste products could recoil through wall openings on thefaçade to create unhealthy indoor environments that could bedangerous to human health. Therefore, the importance of standardsand regulations about the positional arrangements of thewaste gas exhaust ducts of C-type balanced chimney devices onbuilding façades is increasing. In this research, we analyze thestudies of the Institution of Turkish Standards, Chamber of MechanicalEngineers, gas distribution companies, municipalitiesand authorized firms and compare the criteria to determine thenecessary application method. According to our comparison ofthe references accessed, the criteria are not uniform.

Erkan AVLAR

2009-01-01

218

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

Science.gov (United States)

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.

Kühn, Roland; Koeppen, Olaf; Kitte, Jens

2014-06-01

219

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

Science.gov (United States)

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

Najimi, Ebrahim; Ramezani, Mohammad Hossein

2012-03-01

220

40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...  

Science.gov (United States)

40 Protection of Environment 19 2010-07-01 2010-07-01 false Exhaust gas sampling and analytical...A) Small enough in diameter to cause turbulent flow (Reynolds Number greater than 4000) and of sufficient length...

2010-07-01

 
 
 
 
221

Investigation on Exhaust Gas Emissions and the Application of Particulate Filter Systems at Rapeseed Oil-Fuelled Combined Heat and Power Units  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The operation of combined heat and power units (CHP) with rapeseed oil is associated with insecurities, regarding exhaust gas emission characteristics. Thus, the exhaust gas components CO, NOx, HC and particle mass were ascertained at practice units by recurrent measurements, and influences of rapeseed oil quality, operational mode and particulate filter systems were analysed. CHP of technical faultless and with oxidation catalysts feature favourable emission concentrations, varyin...

Thuneke, Klaus

2010-01-01

222

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 re...

Gong Jing; Zhang Yingjia; Tang Chenglong; Huang Zuohua

2014-01-01

223

Characteristics and photochemical potentials of volatile organics emission from stack exhaust gas of industrial processes  

Energy Technology Data Exchange (ETDEWEB)

The main objective of this project was to measure the main volatile organic compounds (VOCs) in stack gas from the downstream petrochemical plants. Six pollution sources of industrial processes, including Acrylonitrile-Butadiene-Styrene (ABS), Vinyl Chloride(VC), Polyvinyl Chloride (PVC), Acrylic Resin, para-Terephthalic Acid (PTA) and Polyurethane (PU) synthetic manufacturing processes, were measured by using USEPA Method 18. The concentration and emission rate database of twenty-seven VOCs has been established. Fifty-two selected stacks were sampled and analyzed for VOCs. Analysis of emission factors and characteristics of the twenty-seven VOCs in these stacks show that the emission characteristics are various among different industrial processes. The order of the single-stack VOCs average emission factor are ABS (1.109 lbs VOCs/ton-ABS; 22 stacks) {gt} Acrylic Resin (0.651 lbs VOCs/ton-acrylic resin; 7 stacks) {gt} PU Synthetic (0.606 lbs VOCs/ton-PU synthetic; 4 stacks) {gt} PTA (0.054 lbs VOCs/ton-PTA; 4 stacks) {gt} PVC (0.014 lbs VOCs/ton-PVC; 11 stacks) {gt} VC ({lt} 0.001; 4 stacks) manufacturing processes. The emission factors of VOC in AP-42 database for the processes of are 5 to 40 times higher than those of VOCs in this research. Because of the equipment of pollutant control setting up before the emitted exhaust gas, their average emission factors in these measured processes are almost lower than those of VOCs in AP-42 database. Compared with the characteristics of VOCs, there is little similarity in VOC characteristics for the stacks of six processes between the results from this research and the data from US EPA SPECIATE data system. Furthermore, according to maximum incremental reactivities (MIR) of VOCs probed into photochemical reaction potentials, the results show that those of PTA manufacturing process have an ozone formation potential of 2.33 g O{sub 3}/g VOCs, which is higher than other processes.

Hsu, Y.C.; Tsai, J.H.; Lin, T.C.; Cheng, C.C.; Huang, Y.H.

1999-07-01

224

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

Science.gov (United States)

...Figure N90-4 is based upon the...The variable mixture flow rate is maintained...square root of the gas temperature...the valves is based on the electronic... (2) The gas mixture temperature, measured...concern with natural gas- and liquefied...condensation is based on the...

2010-07-01

225

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

Science.gov (United States)

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.

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

2013-10-01

226

Desulfurization of the exhaust gas with zeolite synthesized from diatomaceous earth  

Energy Technology Data Exchange (ETDEWEB)

Both A type and X type zeolites were prepared from diatomaceous earth and tested for use in flue gas desulfurization. Several diatomaceous earths of known chemical compositions were mixed to obtain a desired molar ratio of silicates, whose maturation was achieved in two steps; room temperature maturation and reflux maturation by heating. If the second maturation was carried out for more than 12 hr, the X type zeolite formation was low. At the best conditions, 80% pure zeolite could be prepared for both types according to their x-ray diffraction spectra. The synthesized x type zeolite adsorbed sulfur dioxide more efficiently than A type zeolite. When a simulated flue gas containing 680 to 840 ppM sulfur dioxide was passed at a flow rate of 9.0 Nl/min through a 250 g zeolite column, the column breaking time (time required for the SO/sub 2/ concentration of the column effluent to reach 10% of the initial SO/sub 2/ concentration) was 5.3 hr, while that for the commercial zeolite and activated carbon was 6.8 hr and 8.0 hr, respectively. If the flue gas contained more than 1% moisture, the adsorbed water reacted with SO/sub 2/ and the zeolite crystal tended to break down. The use of zeolite for flue gas desulfurization was more costly than the use of activated carbon.

Miyamoto, M.

1975-07-01

227

Carbon dioxide enrichment of greenhouse vegetable through the use of diesel exhaust gas. [Cucumis sativus; Lactuca sp  

Energy Technology Data Exchange (ETDEWEB)

Two cucumber and eight lettuce varieties were grown in two air-supported, closed-environment plastic greenhouses, one with approximately ambient CO2 levels, and the other enriched with 1400 ppm CO2. Diesel exhaust gas was the source of the carbon dioxide. Once the exhaust gases were scrubbed through seawater and put through an activated charcoal filter, essentially no other gases entered the greenhouse along with the CO2. Cucumbers grown in the enriched environment came into production one week earlier, and one variety produced significantly higher yields, than those grown at near ambient levels of CO2. Lettuce grown in the CO2 enriched greenhouse weighed, at market maturity, nearly twice as much as lettuce grown at ambient levels.

Jensen, M.H.; Hodges, C.N.

1970-01-01

228

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

229

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)

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.)

Junge, S.

2002-07-01

230

Temperature modulation of a catalytic gas sensor.  

Science.gov (United States)

The use of catalytic gas sensors usually offers low selectivity, only based on their different sensitivities for various gases due to their different heats of reaction. Furthermore, the identification of the gas present is not possible, which leads to possible misinterpretation of the sensor signals. The use of micro-machined catalytic gas sensors offers great advantages regarding the response time, which allows advanced analysis of the sensor response. By using temperature modulation, additional information about the gas characteristics can be measured and drift effects caused by material shifting or environmental temperature changes can be avoided. In this work a miniaturized catalytic gas sensor which offers a very short response time (<150 ms) was developed. Operation with modulated temperature allows analysis of the signal spectrum with advanced information content, based on the Arrhenius approach. Therefore, a high-precise electronic device was developed, since theory shows that harmonics induced by the electronics must be avoided to generate a comprehensible signal. PMID:25356643

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

2014-01-01

231

Temperature Modulation of a Catalytic Gas Sensor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

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

2014-01-01

232

The effect of temperature and humidity on size segregated traffic exhaust particle emissions  

Science.gov (United States)

The formation and behaviour of exhaust emissions is affected by environmental, traffic and meteorological conditions. The understanding of the governing processes and dependency between particles and other relevant parameters, as well as the magnitude of the impacts, is still limited and mostly based on a few laboratory studies. The focus of this work is the effect of temperature (TEMP) and relative humidity (RH) and their interaction on traffic emission particles in the size range of 15-850 nm. The relationship was assessed using a large data set collected over a period of six months at two road sites in Brisbane. A sequence of statistical analyses were designed and applied in order to quantify the relationships, comprising exploratory correlation analysis to identify pairwise linear associations, factor analysis to assess multivariate effects and nonparametric regression tree methods to more carefully explore interactions. The results show that total particle number concentration was dominated by traffic flow rate and wind speed and to a lesser degree by RH and TEMP. In general, an inverse relationship between TEMP and concentration and a direct relationship between RH and concentration was observed. While TEMP was a dominant parameter for particle concentrations in the size range 15-30 nm, its role diminished and RH emerged as a stronger influence as particle size increased. The observed increase for particle concentrations in the size range 50-150 nm could be associated with particle transfer from a smaller to larger size group due to coagulation and condensation induced growth, as well as an increase in primary (engine) emissions. The significant influence of RH on particles in 150-880 nm size range could be related to particle growth, changes in hygroscopic properties of traffic emissions and particles originating from sources other than traffic. Decreased combustion efficiency may also contribute to higher emissions of particles in this size range.

Jamriska, Milan; Morawska, Lidia; Mergersen, Kerrie

233

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

Science.gov (United States)

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

Castellano, Christopher R. (Ringoes, NJ); Moini, Ahmad (Princeton, NJ); Koermer, Gerald S. (Basking Ridge, NJ); Furbeck, Howard (Hamilton, NJ)

2010-07-20

234

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.

235

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

Science.gov (United States)

...use of a PDP-CVS and a heat exchanger, a CFV-CVS...EFC-CFV-CVS) with either a heat exchanger or electronic...gases in the exhaust duct connected to the dilution tunnel...valves, solenoids, pumps, and switches may be...EFC-CFV-CVS, either a heat exchanger or...

2010-07-01

236

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

Science.gov (United States)

...equal cross-sectional areas of the exhaust duct...distance from the sampling tip to the filter holder shall...filters shall not be in contact with each other. ...60 mm diameter stain area) is 1.3 milligrams...mg/1075 mm2 stain area) shall be used as...

2010-07-01

237

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

Science.gov (United States)

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

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

2008-12-01

238

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)

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.

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

239

Temperature dependence of the MDT gas gain  

CERN Document Server

This note describes the measurements taken in the Gamma Irradiation Facility (GIF) in the X5 test beam area at CERN to investigate the temperature dependence of the MDT drift gas (Ar/CO2 - 90:10). Spectra were taken with an Americium-241 source during the aging studies. We analysed the effects of temperature changes on the pulse height spectrum.

Gaudio, G; Treichel, M

1999-01-01

240

Temporal survey of electron number density and electron temperature in the exhaust of a megawatt MPD-arc thruster.  

Science.gov (United States)

Temporal and radial profiles are obtained 30 cm downstream from the anode for two peak arc currents (11.2 kA and 20 kA) and for various auxiliary magnetic fields (0, 1.0 T, and 2.0 T) using the Thomson scattering technique. Average density and temperature are relatively constant for over 100 microseconds with significant fluctuations. Radial profiles obtained are relatively flat for 4 cm from the axis. Compared to earlier 20 cm data, the exhaust density has decreased significantly, the average temperature has not changed, and the density ?hole' with an auxiliary magnetic field has enlarged.

Michels, C. J.; Rose, J. R.; Sigman, D. R.

1972-01-01

 
 
 
 
241

Finite-temperature trapped dipolar Bose gas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We develop a finite temperature Hartree theory for the trapped dipolar Bose gas. We use this theory to study thermal effects on the mechanical stability of the system and density oscillating condensate states. We present results for the stability phase diagram as a function of temperature and aspect ratio. In oblate traps above the critical temperature for condensation we find that the Hartree theory predicts significant stability enhancement over the semiclassical result. B...

Bisset, R. N.; Baillie, D.; Blakie, P. B.

2012-01-01

242

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Smolenska, H.

2008-01-01

243

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 Cn&...

Erickson, M. H.; Wallace, H. W.; Jobson, B. T.

2012-01-01

244

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Breton, Antoine

2012-01-01

245

Catalysts to reduce NO.sub.x in an exhaust gas stream and methods of preparation  

Science.gov (United States)

Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver on a particulate alumina support, the silver having a diameter of less than about 20 nm. Methods of manufacturing catalysts are described in which ionic silver is impregnated on particulate hydroxylated alumina particles.

Koermer, Gerald S. (Basking Ridge, NJ); Moini, Ahmad (Princeton, NJ); Furbeck, Howard (Hamilton, NJ); Castellano, Christopher R. (Ringoes, NJ)

2012-05-08

246

Exhaust Gas Recirculation Cooler Fouling in Diesel Applications: Fundamental Studies Deposit Properties and Microstructure  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on the results of experimental efforts aimed at improving the understanding of the mechanisms and conditions at play in the fouling of EGR coolers. An experimental apparatus was constructed to utilize simplified surrogate heat exchanger tubes in lieu of full-size heat exchangers. The use of these surrogate tubes allowed removal of the tubes after exposure to engine exhaust for study of the deposit layer and its properties. The exhaust used for fouling the surrogate tubes was produced using a modern medium-duty diesel engine fueled with both ultra-low sulfur diesel and biodiesel blends. At long exposure times, no significant difference in the fouling rate was observed between fuel types and HC levels. Surface coatings for the tubes were also evaluated to determine their impact on deposit growth. No surface treatment or coating produced a reduction in the fouling rate or any evidence of deposit removal. In addition, microstructural analysis of the fouling layers was performed using optical and electron microscopy in order to better understand the deposition mechanism. The experimental results are consistent with thermophoretic deposition for deposit formation, and van der Waals attraction between the deposit surface and exhaust-borne particulate.

Storey, John Morse [ORNL; Sluder, Scott [ORNL; Lance, Michael J [ORNL; Styles, Dan [Ford Motor Company; Simko, Steve [Ford Motor Company

2013-01-01

247

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

Directory of Open Access Journals (Sweden)

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.

Gong Jing

2014-01-01

248

A micro-scale dispersion model for motor vehicle exhaust gas in urban areas—OMG volume-source model  

Science.gov (United States)

A micro-scale dispersion model is presented for estimating the concentration of pollutants from motor vehicle exhaust gas within an area extending 200 m from the side of the road in an urban area. The initial mixing of pollutants in a street canyon is modeled as a volume source employing an analytical solution to the Fickian diffusion equation. Parameters for the model were determined based on data from experiments performed at five locations in Osaka. In the experiments, SF 6 was released as a tracer gas. The height for wind speed measurements for use as the advection speed of the plume was determined from an analysis of the flux of SF 6. The eddy diffusivities in the vertical and lateral directions were derived from statistics of the turbulent velocity fluctuations of the air. The sensitivity analysis of the model revealed that proper characterization of the thickness of the volume source is essential for proper estimation of the concentration of pollutants.

Kono, Hitoshi; Ito, Shozo

249

Meeting future exhaust emissions standards using natural gas as a vehicle fuel: Lessons learned from the natural gas vehicle challenge '92  

Energy Technology Data Exchange (ETDEWEB)

The Natural Gas Vehicle Challenge '92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated exhaust constituents. Nine of the student-modified trucks passed the current levels of exhaust emission standards, and some exceeded the strictest future emissions standards envisioned by the US Environmental Protection Agency. Factors in achieving good emissions control using natural gas are summarized, and observations concerning necessary components of a successful emissions control strategy are presented.

Rimkus, W.A.; Larsen, R.P.

1992-01-01

250

Meeting future exhaust emissions standards using natural gas as a vehicle fuel: Lessons learned from the natural gas vehicle challenge `92  

Energy Technology Data Exchange (ETDEWEB)

The Natural Gas Vehicle Challenge `92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated exhaust constituents. Nine of the student-modified trucks passed the current levels of exhaust emission standards, and some exceeded the strictest future emissions standards envisioned by the US Environmental Protection Agency. Factors in achieving good emissions control using natural gas are summarized, and observations concerning necessary components of a successful emissions control strategy are presented.

Rimkus, W.A.; Larsen, R.P.

1992-09-01

251

Lightweight Exhaust Manifold and Exhaust Pipe Ducting for Internal Combustion Engines  

Science.gov (United States)

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.

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

1999-01-01

252

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)

253

Influence of heat pipe operating temperature on exhaust heat thermoelectric generation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Brito, F. P.; Martins, Jorge; Gonc?alves, L. M.; Antunes, Nuno; Sousa, Diogo

2013-01-01

254

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

International Nuclear Information System (INIS)

The aim of the research described in this thesis is the development of a mixed conducting oxide layer, which can be used as an oxygen permselective membrane in an amperometric NOx sensor. The sensor will be used in exhaust gas systems. The exhaust gas-producing engine will run in the lean mix mode. The preparation of this sensor is carried out using screen-printing technology, in which the different layers of the sensor are applied successively. Hereafter, a co-firing step is applied in which all layers are sintered together. This co-firing step imposes several demands on the selection of materials. The design specifications of the sensor further include requirements concerning the operating temperature, measurement range and overall stability. The operating temperature of the sensor varies between 700 and 850C, enabling measurement of NOx concentrations between 50 and 1200 ppm with a measurement accuracy of 10 ppm. Concerning the stability of the sensor, it must withstand the exhaust gas atmosphere containing, amongst others, smoke, acids, abrasive particles and sulphur. Because of the chosen lean-mix engine concept, in which the fuel/air mixture switches continuously between lean (excess oxygen) and fat (excess fuel) mixtures, the sensor must withstand alternately oxidising and reducing atmospheres. Besides, it should be resistant to thermal shock and show no cross-sensitivity of NOx with other exhaust gas constituents like oxygen and hydrocarbons. The response timeoxygen and hydrocarbons. The response time should be short, typically less than 500 ms. Because of the application in combustion engines of cars, the operational lifetime should be longer than 10 years. Demands on the mixed conducting oxide layer include the following ones. The layer should show minimal catalytic activity towards NOx-reduction. The oxygen permeability must be larger than 6.22 10-8 mol/cm2s at a layer thickness between 3-50 ?m. Since the mixed conducting oxide layer is coated on the YSZ electrolyte embodiment, the two materials must be co-firable and, hence, match in thermal, chemical and mechanical behaviour. A number of studies on different mixed oxygen ion/electron conducting materials is described in this thesis. Emphasis is put on the demands of the targeted sensor application, in which these materials are used as mixed conducting dense ceramic membranes. In Chapter 2, a series of perovskite materials is studied. The general composition is ABO3-? (A = Gd, Pr, Y; B = Mn, Cr, Fe), being partially doped with Ca2+ and Sr2+ on the A-site to create mobile oxygen vacancies. The main focus of the work presented is on the measurement of catalytic activities towards NOx and the ionic conductivities of the selected materials. In Chapter 3, the preparation and characterisation of a material with the overall composition of Gd0.7Ca0.3CoOx is described. Dual phase composite membranes are the subject of investigations presented in Chapters 4-7. The main advantage of these type of materials is that their properties can be tailored to meet the demands imposed by the sensor design. Emphasis is on the preparation of the materials, characterisation by SEM-EDX, XRD, catalytic activity and measurement of ionic/electronic conductivities. In Chapter 4, dual phase composites of composition Gd0.7Ca0.3CoOx/Ce0.8Gd0.2O2- are studied. Composites ZrO2/In2O3 and ZrO2/ITO are subject to the investigations reported in Chapters 5 and 6, respectively. Finally, in Chapter 7, composite Au/YSZ and Au/Ce0.8Gd0.2O2- membranes are studied. Finally, in Chapter 8 a summary of the results is given together with recommendations for future research

255

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

Khalykov Kamil Rafaelevich; Gorbachev Maksim Mikhaylovich; Vinogradov Sergey Vladimirovich

2010-01-01

256

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

Directory of Open Access Journals (Sweden)

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.

M. H. Erickson

2012-02-01

257

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

Directory of Open Access Journals (Sweden)

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.

Jitendra kumar

2013-07-01

258

Argon/UF6 plasma exhaust gas reconstitution experiments using preheated fluorine and on-line diagnostics. [fissioning uranium plasma core reactor design  

Science.gov (United States)

The feasibility of employing a flowing, high-temperature, pure fluorine/UF6 regeneration system to efficiently convert a large fraction of the effluent plasma exhaust back to pure UF6 was demonstrated. The custom built T.O.F. mass spectrometer sampling system permitted on-line measurements of the UF6 concentration at different locations in the exhaust system. Negligible amounts ( 100 ppm) of UF6 were detected in the axial bypass exhaust duct and the exhaust ducts downstream of the cryogenic trap system used to collect the UF6, thus verifying the overall system efficiency over a range of operating conditions. Use of a porous Monel duct as part of the exhaust duct system, including provision for injection of pure fluorine, provided a viable technique to eliminate uranium compound residue on the inside surface of the exhaust ducts. Typical uranium compound mass deposition per unit area of duct was 2 micron g/sq cm. This porous duct technique is directly applicable to future uranium compound transfer exhaust systems. Throughout these experiments, additional basic data on the corrosion aspects of hot, pressurized UF6/fluorine were also accumulated.

Roman, W. C.

1979-01-01

259

Innovative exhaust gas recirculation system for economic and fuel efficient compliance of future emission standards; Innovatives Abgasrueckfuehrsystem zur kosten- und verbrauchseffizienten Erfuellung zukuenftiger Emissionsvorschriften  

Energy Technology Data Exchange (ETDEWEB)

An innovative Exhaust Gas Recirculation (EGR) system is presented, which generates by means of a rotating flap temporary depressions wave balanced to each engine operating condition. This assures a sufficient pressure difference for EGR. By the integral control of the charge air and exhaust gas mass flow, the system provides the opportunity to both, increase the EGR rate and reduce the gas exchange work. Given the systems highly efficient and flexible electronic activation, the valves enable the desired exhaust gas flow rates both across the entire engine operating map and during engine cold starts. The importance of the cold start and engine warm up period increases significantly in terms of future emission standards. Experimental results of a heavy-duty engine application will be presented. With this system, EGR flow rates can be increased for over 50% over a wide range of the map of heavy-duty diesel engines. Thereby clear advantages in NO{sub x}-emission and specific fuel consumption are demonstrated. Thus a considerable potential to reduce the time and effort for the exhaust gas aftertreatment by using internal motor measures only is shown. (orig.)

Mahr, Bernd [Mahle GmbH, Stuttgart (Germany); Warth, Marco; Rueckauf, Joerg; Elsaesser, Alfred [MAHLE International GmbH, Stuttgart (Germany)

2009-07-01

260

Dynamic characteristics of a hydrostatic gas bearing driven by oscillating exhaust pressure  

Science.gov (United States)

Vibration of a statically loaded, inherently compensated hydrostatic journal bearing due to oscillating exhaust pressure is investigated. Both angular and radial vibration modes are analyzed. The time-dependent Reynolds equation governing the pressure distribution between the oscillating journal and sleeve is solved together with the journal equation of motion to obtain the response characteristics of the bearing. The Reynolds equation and the equation of motion are simplified by applying regular perturbation theory for small displacements. The numerical solutions of the perturbation equations are obtained by discretizing the pressure field using finite-difference aproximations with a discrete, nonuniform line-source model which excludes effects due to feeding hole volume. An iterative scheme is used to simultaneously satisfy the equations of motion for the journal. The results presented include Bode plots of bearing-oscillation gain and phase for a particular bearing configuration for various combinations of parameters over a range of frequencies, including the resonant frequency.

Watkins, C. B.; Eronini, I. E.; Branch, H. D.

1984-01-01

 
 
 
 
261

Review of homogeneous charge compression ignition (HCCI) combustion engines and exhaust gas recirculation (EGR) effects on HCCI  

Science.gov (United States)

This paper describes the development in ICE which leads to the new advanced combustion mode named Homogeneous Charge Compression Ignition (HCCI). It explains regarding the theory and working principle of HCCI plus the difference of the process in gasoline and diesel fuelled engines. Many of pioneer and recent research works are discussed to get the current state of art about HCCI. It gives a better indication on the potential of this method in improving the fuel efficiency and emission produced by the vehicles' engine. Apart from the advantages, the challenges and future trend of this technology are also included. HCCI is applying few types of control strategy in producing the optimum performance. This paper looks into Exhaust Gas Recirculation (EGR) as one of the control strategies.

Akma Tuan Kamaruddin, Tengku Nordayana; Wahid, Mazlan Abdul; Sies, Mohsin Mohd

2012-06-01

262

46 CFR 58.10-15 - Gas turbine installations.  

Science.gov (United States)

...Commandant. (4) A gas turbine exhaust on a mobile...system. (2) A gas turbine air inlet must not...shutdown. (1) The control system shall be... (i) Excessive gas temperature, measured at the turbine inlet, gas...

2010-10-01

263

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

Energy Technology Data Exchange (ETDEWEB)

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.

Wu, Ko-Jen

2011-12-31

264

Operating limitations due to low gas temperature  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1995-12-31

265

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

Directory of Open Access Journals (Sweden)

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.

Nor Halim Hasan

2013-08-01

266

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)

267

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

Science.gov (United States)

...sampling and analytical system; diesel engines. (a) General. The...gas-fueled and methanol-fueled heavy-duty diesel engines. This system utilizes the CVS...sampling of the particulate material may then take place...

2010-07-01

268

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

Science.gov (United States)

...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...

2010-07-01

269

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

Science.gov (United States)

...vehicles and light light-duty trucks. 86.1710-99 Section 86.1710-99 Protection of Environment ENVIRONMENTAL PROTECTION...Light-Duty Vehicles and Light-Duty Trucks § 86.1710-99 Fleet average non-methane organic gas exhaust...

2010-07-01

270

Analysis Proton Conducting Electrolyte IT-SOFC Hybrid System Exhaust Gas With External Reforming of Biofuel  

Directory of Open Access Journals (Sweden)

Full Text Available In this analysis, a hybrid system containing proton SOFC (P-SOFC combine with micro gas turbine (MGT with biofuel external reforming is investigation to decrease the greenhouse gases problem facing in electrical power plant. The hybrid system consist of a proton solid oxide fuel cell stack, a micro gas turbine, a combustor, compressors, heat exchangers and external reformer. The main operating parameter such as, fuel utilization and steam - carbon ratio is determined in this analysis.

Nizar Amir

2013-03-01

271

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

272

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

Directory of Open Access Journals (Sweden)

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.

Jarvie Daniel M

2009-11-01

273

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2000-04-01

274

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

275

Intensity of corrosion processes in exhaust gas boilers at burning water-fuel emulsion  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Approximation dependences of specific rates of low-temperature sulfur corrosion and pollution intensity under the influence of the main parameters characterizing these processes are presented. Statistical processing of the research results that displayed the primary influence on decrease in metal sulfur and water content of water fuel emulsion is conducted. The dependences of low-temperature sulfur corrosion rate on the wall temperature for 100 and 1000 hours at burning standard fuel and wate...

Goryachkin Vladimir Yurievich; Kornienko Victoriya Sergeevna

2013-01-01

276

A catalog of intracluster gas temperatures  

Science.gov (United States)

We have searched the Einstein Monitor Proportional Counter (MPC) data base for observations of clusters of galaxies. By coadding the MPC spectra obtained during all pointed observations of clusters with IPC count rates greater than 0.1 counts/s, we have obtained sufficient photon statistics to estimate the X-ray temperature of 84 clusters. Combining the MPC results with EXOSAT and Ginga results reported in the literature yields a combined sample of 104 clusters with known X-ray temperatures. One of the best studied X-ray correlations between clusters is that between their X-ray luminosity and gas temperature. We show that the best-fit power-law relation for our combined cluster sample can be explained by the observed increase in the gas-to-stellar mass ratio between low- and high-temperature clusters. The statistical significance of any evolution in our combined X-ray sample has been examined and compared with the statistical properties of clusters culled from optical catalogs. We find that there is strong evidence for a decrease in the X-ray luminosity of optically rich clusters beyond z approximately about 0.06. This result is used to estimate the normalization of the primordial power spectrum of density fluctuations.

David, L. P.; Slyz, A.; Jones, C.; Forman, W.; Vrtilek, S. D.; Arnaud, K. A.

1993-01-01

277

High temperature gas-cooled reactor: gas turbine application study  

Energy Technology Data Exchange (ETDEWEB)

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.

1980-12-01

278

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

Science.gov (United States)

...Filters. Glass fiber filter paper is permitted for the fine particulate...01 inches (0.03 cm). The wall thickness of the probe shall...locomotives and engines, the wall temperature of the HC sample line... (C) For all fuels, wall temperature of the NOX...

2010-07-01

279

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

Science.gov (United States)

...select zero or calibration gases; V2 are optional heated...select sample or span gases; V4, V6, and V15 are...select sample or span gases; V10 and V12—heated flow... (I) Temperature sensor. A temperature sensor (T1) to measure the NO2 to NO converter...

2010-07-01

280

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

Science.gov (United States)

...measure the input to the CO and CO2 analyzers...the exit pressure of the CO and CO2 analyzers... (I) Temperature sensor. A temperature sensor...protrusions (due to sensors, etc.) should be smooth...used. (D) Diluted CO 2 sample...

2010-07-01

 
 
 
 
281

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...

282

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)

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.)

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

2008-07-01

283

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

Science.gov (United States)

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

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

2011-06-01

284

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.)

285

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

286

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

Science.gov (United States)

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.

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

2006-01-01

287

Flow characteristics in the exhaust of a pulsed megawatt gas fed arc  

Science.gov (United States)

The transient flow generated by a pulsed, megawatt-level, gas-fed arc with an applied magnetic nozzle has been examined with a new design piezoelectric pressure transducer. Sensor thermal conduction and accelerations have been examined and eliminated in the 500 microsec period of plasma flow. Existence of a large magnitude cold gas pressure front of 20 microsec duration has been reconfirmed and its relationship to the following plasma flow of about 200 microsec duration has been examined for the first time. At a point 30 cm from the arc source, initially near vacuum conditions (typically with an arc current of 11.2 kA and 1 tesla applied magnetic field), a pressure pulse of unionized gas with a magnitude of 10,000 N/sq m is followed by plasma flows with nearly constant impact pressure of 1000 N/sq m. Pressure and number density in this plasma region are seen to decrease with applied magnetic field strength.

Michels, C. J.; York, T. M.

1973-01-01

288

Bimodular high temperature planar oxygen gas sensor  

Directory of Open Access Journals (Sweden)

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

YuLei

2014-08-01

289

Gas-Alloy Interactions at Elevated Temperatures  

Energy Technology Data Exchange (ETDEWEB)

The understanding of the stability of metals and alloys against oxidation and other detrimental reactions, to the catalysis of important chemical reactions and the minimization of defects associated with processing and synthesis have one thing in common: At the most fundamental level, all these scientific/engineering problems involve interactions between metals and alloys (in the solid or liquid state) and gaseous atmospheres at elevated temperatures. In this special issue, we have collected a series of articles that illustrate the application of different theoretical, computational, and experimental techniques to investigate gas-alloy interactions.

Arroyave, Raymundo; Gao, Michael

2012-12-01

290

High temperature surface protection. [10 gas turbines  

Science.gov (United States)

Alloys of the MCrAlX type are the basis for high temperature surface protection systems in gas turbines. M can be one or more of Ni, Co, or Fe and X denotes a reactive metal added to enhance oxide scale adherence. The selection and formation as well as the oxidation, hot corrosion and thermal fatigue performance of MCrAlX coatings are discussed. Coatings covered range from simple aluminides formed by pack cementation to the more advanced physical vapor deposition overlay coatings and developmental plasma spray deposited thermal barrier coatings.

Levine, S. R.

1978-01-01

291

Gas hydrate formation technology using low-temperature and low-pressure conditions part 2 - study on application to CO2 separation with a bench plant  

Energy Technology Data Exchange (ETDEWEB)

Sequestering carbon dioxide (CO2) is an important solution to protect our climate. One of the main CO2 emissions is from burning fossil fuels, such as coal, oil and natural gas. Since CO2 concentration in various exhaust gas is usually low, it is difficult to separate CO2 economically from large amount of exhaust gas. Gas hydrate is a crystalline compound that can contain large amount of gas molecules. Also it is known as a useful gas separation material. Usually for the mixed gas with very low CO2 concentration, it is considered to be difficult to concentrate CO2 content in the gas hydrate. Newly developed hydrate equilibrium prediction method reveals that hydrate can contain CO2 with high concentration even though from mixed gas with low CO2 concentration at low temperature and low pressure condition. Our basic experimental research also supports the interesting phenomena. (It will be reported in part 1 in detail.) In our research, a bench plant was built to verify reaction conditions and to obtain engineering data using N2-CO2 mixed gas simulating exhaust gas from natural gas fired gas turbine power plant. This paper presents outline of the bench plant and some experimental data. (Author)

Tanaka, Susumu; Takano, Osamu; Uchida, Kazuo; Emi, Hiroshi; Kohara, Mitsuhiro; Yamamoto, Yoshitaka; Kawamura, Taro; Ohtake, Michica; Takeya, Satoshi; Yoon, Ji-Ho

2005-07-01

292

Optical fiber sensor for temperature measurement from 600 to 1900 C in gas turbine engines  

Science.gov (United States)

A temperature sensor system has been fabricated specifically for the harsh environment encountered in temperature measurement on gas turbine engines. Four components comprised the system: a thermally emissive source, a high temperature lightguide, a flexible optical cable and an electro-optic signal processor. The emissive source was located inside a sapphire rod so that the sapphire serves as both a lightguide and as a protective shroud. As the probe was heated, the thermal radiation from the emissive source increased with increasing temperature. The flexible optical cable was constructed with 200 micron core fiber and ruggedized for turbine engine applications. The electro-optic signal processor used the ratio of intensity in two wavelength intervals to determine a digital value of the temperature. The probe tip was operated above 1900 C in a low velocity propane flame and above 1500 C at Mach .37. Probe housings, optical cables, and signal processors were constructed and environmentally tested for the temperature and vibration experienced by turbine engine sensors. This technology was used to build an optical exhaust gas sensor for a General Electric Aircraft Engines F404 turbine. The four optical probes and optical cable were a functional replacement for four thermocouple probes. The system was ground tested for 50 hours with an excess of 1000 thermal cycles. This optical temperature sensor system measured gas temperature up to the operational limit of the turbine engine.

Tregay, G. W.; Calabrese, P. R.; Kaplin, P. L.; Finney, M. J.

1991-12-01

293

Development of High Temperature Gas Sensor Technology  

Science.gov (United States)

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

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

1997-01-01

294

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)

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.

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

2014-12-01

295

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

296

Fat from the food industry as regenerative fuels. Chemical treatment, fuel production, exhaust gas analysis; Fette aus der Lebensmittelindustrie als regenerative Kraftstoffe. Aufbereitung, Kraftstoffherstellung, Abgasanalytik  

Energy Technology Data Exchange (ETDEWEB)

The author investigates the possibility to purify and transesterify edible and animal fat to produce a fuel for combustion engines. This fuel is used for combined heat and power plants. Exhaust gas analysis during the combustion process of this fuel showed emission of dioxin and furan from selected charges of fuel, systematically contaminated with polychlorinated biphenyls (PCB). No toxic contamination was found. Transesterification was performed in a pilot plant; the transesterification of edible fat is similar to that of the common industrial transesterification of rape oil. The transesterification of animal fat is more laborious due to the higher concentration of free fatty acids. The results of the exhaust gas measurements show that compared to diesel fuel no principle disadvantage was found when fatty acid methyl ester of edible or animal fat is used as fuel. The use of fat with high contamination of PCB as raw material for the fatty acid methyl ester production did not show dangerous emissions of dioxins or furans.

Rauber, F.M.

2007-07-01

297

Nanocrystalline Pt thin films prepared by electrostatic spray deposition for automotive exhaust gas treatment  

Energy Technology Data Exchange (ETDEWEB)

The deposition of a platinum electrode on 8 mol% Y{sub 2}O{sub 3}-stabilized ZrO{sub 2} (YSZ) using the electrostatic spray deposition (ESD) technique was investigated. Films with various morphologies were obtained starting from different precursor solutions based on Pt(NH{sub 3}){sub 4}(OH){sub 2}(H{sub 2}O), PtCl{sub 4} and Pt(acac){sub 2} dissolved in different solvents. The surface morphology was strongly influenced by the composition of the precursor solution, the deposition temperature, the nozzle to substrate distance, the precursor solution flow rate and the deposition time. The processes involved in the film formation were discussed. Nanocrystalline cubic Pt single-phase was present in the raw film as shown by X-ray diffraction. (author)

Lintanf, A.; Neagu, R.; Djurado, E. [Laboratoire d' Electrochimie et de Physico-Chimie des Materiaux et des Interfaces, Institut National Polytechnique de Grenoble, Domaine Universitaire, BP 75, 1130 rue de la Piscine, 38402 St Martin d' Heres Cedex (France)

2007-01-15

298

Exhaust gas catalyst support made of inorganic moulding material. Abgaskatalysator-Traeger aus anorganischen Formmassen  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is the simplification of a manufacturing process for the manufacture of ceramic catalyst supports, such as are used in vehicles or industrial plants. According to the invention, this is done in a simple way, where, when casting the moulding material aluminium bars or wires are placed in the ceramic support and these react with the alkalis of the moulding material, forming hydrogen and aluminium oxi-hydrate and so forming hollows in the ceramic support. According to the invention, the foreign body is produced from a flowing moulding material by hardening at 60 to 120/sup 0/C in a mould, where by the reaction an oxide mixtures with contents of amorphous SiO/sub 2/ and aluminium oxide and/or electrofilter ash from high temperature hardcoal-fired power stations and/or calcined ground bauxite and/or metakaolin are produced. (HWJ).

1985-12-05

299

Low temperature heat source for power generation: Exhaustive analysis of a carbon dioxide transcritical power cycle  

International Nuclear Information System (INIS)

The main results of a theoretical work on the use of a low temperature heat source for power generation through a carbon dioxide transcritical power cycle are reported in this paper. The procedure for analyzing the behaviour of the proposed cycle consisted in modifying the input pressure to the turbine from 66 bar, maintained constant each evaluated temperature (60 oC, 90 oC, 120 oC and 150 oC) until the net work was approximately zero. As a result, the maximum exergy efficiency was 50%, while the energy efficiencies obtained were 9.8%, 7.3%, 4.9% and 2.4% and the net specific work was 18.2 kJ/kg, 12.8 kJ/kg, 7.8 kJ/kg and 3.5 kJ/kg, respectively. Furthermore, the effect of the addition of an internal heat exchanger, which obviously supposed an increase in the efficiency, was analyzed. The analysis of the proposed system shows the viability of implementing this type of process as an energy alternative and/or strengthener of non-conventional energy sources in non-provided zones, or for increasing the energy efficiency in the industry. -- Highlights: ? Energy and exergy analysis of a carbon dioxide transcritical power cycle is reported. ? The effect of the inlet temperature to the turbine is evaluated. ? Conditions of maximum efficiency and maximum net work are compared. ? The inclusion of an IHX is also analysed.

300

Comparative Design Study of a Diesel Exhaust Gas Heat Exchanger for Truck Applications with Conventional and State of the Art Heat Transfer Enhancements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract The exhaust gas of heavy duty diesel engines can provide an important heat source that may be used in a number of ways to provide additional power and improve overall engine efficiency. The sizing of a heat exchanger that can manage the heat load and still be of reasonable size and weight without excessive pressure drop is of significant importance especially for truck applications. This is the subject of the present work. To approach the problem, a total of five different...

Mavridou, S.; Mavropoulos, G. C.; Bouris, D.; Hountalas, D. T.; Bergeles, G.

2010-01-01

 
 
 
 
301

Additives for rapeseed oil fuel. Influence on the exhaust gas emissions  

Energy Technology Data Exchange (ETDEWEB)

In contrast to fossil diesel fuel, the use of additives is not common in rapeseed oil fuel. In a preceding research project the efficacy of several additives, that are commercially available for the use in fossil diesel or FAME, has been investigated for rapeseed oil fuel in the lab. Four additives could be identified, which have a significant influence on the ignition delay or the low temperature flow behaviour of rapeseed oil fuel. To investigate whether there are negative effects of the additives on other fuel-related properties in practical use, a test series on an agricultural tractor capable of running on vegetable oils has been conducted. Attention is focused on the operating parameters like power, torque or fuel consumption as well as on regulated emissions (CO, HC, particulate matter or NOx) and non-regulated emissions like polycyclic aromatic hydrocarbons. Additionally, the influence of the additives on the storage stability of rapeseed oil fuel is investigated in long term studies. No negative influence of the additives on the regulated emissions could be seen in the experiments, the data of the non-regulated emissions is still being analysed. This paper will focus on the emissions testing; results of the long term studies will be given in the presentation. (orig.)

Kastl, Johannes; Remmele, Edgar; Thuneke, Klaus [Technologie- und Foerderzentrum, Straubing (Germany)

2013-06-01

302

Electron beam flue gas treatment process for purification of exhaust gases with high SO{sub 2} concentrations  

Energy Technology Data Exchange (ETDEWEB)

Exhaust gases with high SO{sub 2} concentrations are emitted from combustion of high sulphur fossil fuels and from different industrial processes (e.g. copper smelter and sintering plants). The application of the electron beam process for SO{sub 2} and NOx removal from such flue gases was investigated. A parametric study was carried out to determine the SO{sub 2} and NOx removal efficiency as a function of temperature and humidity of irradiated gases, absorbed dose and ammonia stoichiometry. The efficiency 90-95% of SO{sub 2} removal was obtained in the optimal treatment conditions with an inlet SO{sub 2} concentration of up to 15% vol. The synergistic effect of high SO{sub 2} content on NOx removal was indicated. The collected by-product was a mixture of ammonium sulphate and nitrate. The content of heavy metals in the by-products was many times lower than the values accepted for commercial fertilizers.

Chmielewski, A.G.; Licki, J. [Institute of Atomic Energy, Otwock (Poland). Dept. of Nuclear Energy

2008-07-01

303

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.)

304

Stop-Start operation of diesel engines - modified requirement for exhaust gas aftertreatment?; Stopp-Start beim Dieselmotor - geaenderte Anforderung fuer die Abgasnachbehandlung?  

Energy Technology Data Exchange (ETDEWEB)

The performed tests show the potential of Stop-Start operation to successfully reduce CO{sub 2} emissions. According to the application a reduction of at least 4 to 5 % is feasible. The impact of Stop-Start operation on the engine-out emissions is low. While on the vehicle some slightly higher HC and CO emissions were detected the test on the engine test bench showed reduced engine-out HC and CO emissions. For the NO{sub x} emission it is vice-versa. The conversion efficiency of the catalyst system depends on application and the ageing status of the catalyst. It is well known that the catalyst temperature is one of the main factors on efficiency. Therefore, operating the engine in a Stop-Start mode should have a positive impact on the HC and CO conversion efficiency as the typical cooling of the DOC due to cold exhaust gas during idling is reduced. Unfortunately this benefit could not be observed, as at this point of time no aged catalysts were evaluated. Nevertheless it should be kept in mind that longer periods with the engine turned off can result in a significant temperature drop downstream of the DPF. Especially for a NO{sub x} device which most probably has to be mounted in an underfloor position - downstream of the DPF - it can result in a delayed light-off and higher emissions and has to be taken into account for engine calibration. So from today's point of view the requirements on the DOC and catalysed DPF are not increasing due to an implementation of a Stop-Start strategy. However, for a NO{sub x} device and its application this new operational conditions have to be checked carefully. (orig.)

Spurk, P.C.; Noack, H.D. [Umicore AG und Co. KG (Germany); Gerhard, S.; Zelenka, B. [Technische Univ. Darmstadt (Germany)

2008-07-01

305

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

Science.gov (United States)

...requires the continuous measurement and comparison of raw exhaust static pressure observed...with the addition of electronic flow controllers, metering valves, separate flow meters...volumes may be obtained from the flow controllers, with advance approval of the...

2010-07-01

306

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

Science.gov (United States)

...the exhaust duct connected to the dilution...Positive displacement pump. The Positive...mixing assembly, heat exchanger, positive displacement pump, sampling systems...positive displacement pump and after the heat exchanger, shall be...

2010-07-01

307

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2001-10-01

308

Mean gas opacity for circumstellar environments and equilibrium temperature degeneracy  

CERN Document Server

In a molecular cloud dust opacity typically dominates over gas opacity, yet in the vicinities of forming stars dust is depleted, and gas is the sole provider of opacity. In the optically thin circumstellar environments the radiation temperature cannot be assumed to be equal to the gas temperature, hence the two-temperature Planck means are necessary to calculate the radiative equilibrium. By using the two-temperature mean opacity one does obtain the proper equilibrium gas temperature in a circumstellar environment, which is in a chemical equilibrium. A careful consideration of a radiative transfer problem reveals that the equilibrium temperature solution can be degenerate in an optically thin gaseous environment. We compute mean gas opacities based on the publicly available code DFSYNTHE by Kurucz and Castelli. We performed the calculations assuming local thermodynamic equilibrium and an ideal gas equation of state. The values were derived by direct integration of the high-resolution opacity spectrum. We prod...

Malygin, M G; Klahr, H; Dullemond, C P; Henning, Th

2014-01-01

309

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Sureshkumar, K.; *, K.Muralidharan

2014-01-01

310

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)

311

First online measurements of sulfuric acid gas in modern heavy-duty diesel engine exhaust: implications for nanoparticle formation.  

Science.gov (United States)

To mitigate the diesel particle pollution problem, diesel vehicles are fitted with modern exhaust after-treatment systems (ATS), which efficiently remove engine-generated primary particles (soot and ash) and gaseous hydrocarbons. Unfortunately, ATS can promote formation of low-vapor-pressure gases, which may undergo nucleation and condensation leading to formation of nucleation particles (NUP). The chemical nature and formation mechanism of these particles are only poorly explored. Using a novel mass spectrometric method, online measurements of low-vapor-pressure gases were performed for exhaust of a modern heavy-duty diesel engine operated with modern ATS and combusting low and ultralow sulfur fuels and also biofuel. It was observed that the gaseous sulfuric acid (GSA) concentration varied strongly, although engine operation was stable. However, the exhaust GSA was observed to be affected by fuel sulfur level, exhaust after-treatment, and driving conditions. Significant GSA concentrations were measured also when biofuel was used, indicating that GSA can be originated also from lubricant oil sulfur. Furthermore, accompanying NUP measurements and NUP model simulations were performed. We found that the exhaust GSA promotes NUP formation, but also organic (acidic) precursor gases can have a role. The model results indicate that that the measured GSA concentration alone is not high enough to grow the particles to the detected sizes. PMID:23035617

Arnold, F; Pirjola, L; Rönkkö, T; Reichl, U; Schlager, H; Lähde, T; Heikkilä, J; Keskinen, J

2012-10-16

312

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

Directory of Open Access Journals (Sweden)

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.

D. A. Lack

2012-05-01

313

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

Directory of Open Access Journals (Sweden)

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.

D. A. Lack

2012-01-01

314

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

DEFF Research Database (Denmark)

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.

Evseev, Vadim; Clausen, SØnnik

2009-01-01

315

In situ gas temperature measurements by UV-absorption spectroscopy  

DEFF Research Database (Denmark)

The absorption spectrum of the NO A(2)Sigma(+) <- X(2)Pi gamma-system can be used for in situ evaluation of gas temperature. Experiments were performed with a newly developed atmospheric-pressure high-temperature flow gas cell at highly uniform and stable gas temperatures over a 0.533 m path in the range from 23 degrees C to 1,500 degrees C. The gas temperature was evaluated (1) from the analysis of the structure of selected NO high-resolution gamma-absorption bands and (2) from the analysis of vibrational distribution in the NO gamma-absorption system in the (211-238) nm spectral range. The accuracy of both methods is discussed. Validation of the classical Lambert-Beer law has been demonstrated at NO concentrations up to 500 ppm and gas temperatures up to 1,500 degrees C over an optical absorption path length of 0.533 m.

Fateev, Alexander; Clausen, SØnnik

2009-01-01

316

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

DEFF Research Database (Denmark)

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.

Clausen, SØnnik; SØrensen, L.H.

2006-01-01

317

HPF HIGH PRESSURE FACILITY GAS ANALYSIS SYSTEM IN BASEMENT / HIGH TEMPERATURE GAS FACILITY IN THE E  

Science.gov (United States)

HPF HIGH PRESSURE FACILITY GAS ANALYSIS SYSTEM IN BASEMENT / HIGH TEMPERATURE GAS FACILITY IN THE ENGINE RESEARCH BUILDING ERB TEST CELL CE-13 / AUTOMATIC SCAN VALUE SYSTEM ON THE SECOND FLOOR OF THE INSTRUMENT RESEARCH LABORATORY IRL

1980-01-01

318

Regenerable sorbents for low temperature desulfurization of coal gas  

Energy Technology Data Exchange (ETDEWEB)

Z-Sorb{trademark} sorbent has been shown to be effective for the removal of hydrogen sulfide from hot gas (1,000 F) streams using fixed-, moving- and fluid-bed systems. Recent work with modified formulations suggests the sorbent temperature application range can be expanded to include the lower temperatures (600--800 F) used for moderate temperature gas cleanup. Data will be presented from experiments with both fixed and fluid bed work.

Khare, G.P.; Greenwood, G.J.; Kubicek, D.H.; Delzer, G.A. [Phillips Petroleum Co., Bartlesville, OK (United States)

1995-12-31

319

Experimental study of heat transfer coefficient in exhaust pipe  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2010-07-01

320

Method for high temperature mercury capture from gas streams  

Energy Technology Data Exchange (ETDEWEB)

A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum are effective for mercury removal from fuel gas (syngas). An iridium-platinum alloy is suitable for metal capture in many industrial effluent gas streams including highly corrosive gas streams.

Granite, E.J.; Pennline, H.W.

2006-04-25

 
 
 
 
321

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)

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.

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

2012-11-01

322

A Precise Calibration Technique for Measuring High Gas Temperatures  

Science.gov (United States)

A technique was developed for direct measurement of gas temperatures in the range of 2050 K - 2700 K with improved accuracy and reproducibility. The technique utilized the low-emittance of certain fibrous Materials, and the uncertainty of the technique was limited by the uncertainty in the melting points of the materials, i.e., +/- 15 K. The materials were pure, thin, metal-oxide fibers whose diameters varied from 60 mm to 400 mm in the experiments. The sharp increase in the emittance of the fibers upon melting was utilized as indication of reaching a known gas temperature. The accuracy of the technique was confirmed by both calculated low emittance values of transparent fibers, of order 0.01, up to a few degrees below their melting point and by the fiber-diameter independence of the results. This melting-point temperature was approached by increments not larger than 4 K, which was accomplished by controlled increases of reactant flow rates in hydrogen-air and/or hydrogen- oxygen flames. As examples of the applications of the technique, the gas-temperature measurements were used (a) for assessing the uncertainty in infering gas temperatures from thermocouple measurements, and (b) for calibrating an IR camera to measure gas temperatures. The technique offers an excellent calibration reference for other gas-temperature measurement methods to improve their accuracy and reliably extending their temperature range of applicability.

Gokoglu, Suleyman A.; Schultz, Donald F.

1999-01-01

323

Durable fiber optic sensor for gas temperature measurement in the hot section of turbine engines  

Science.gov (United States)

An optical sensor system extends gas temperature measurement capability in turbine engines beyond the present generation of thermocouple technology. The sensing element which consists of a thermally emissive insert embedded inside a sapphire lightguide is capable of operating above the melting point of nickel-based super alloys. The emissive insert generates an optical signal as a function of temperature. Continued development has led to an optically averaged system by combining the optical signals from four individual sensing elements at a single detector assembly. The size of the signal processor module has been reduced to overall dimensions of 2 X 4 X 0.7 inches. The durability of the optical probe design has been evaluated in an electric-utility operated gas turbine under the sponsorship of the Electric Power Research Institute. The temperature probe was installed between the first stage rotor and second stage nozzle on a General Electric MS7001B turbine. The combined length of the ceramic support tube and sensing element reached 1.5 inches into the hot gas stream. A total of over 2000 hours has been accumulated at probe operation temperatures near 1600 degree(s)F. An optically averaged sensor system was designed to replace the existing four thermocouple probes on the upper half of a GE F404 aircraft turbine engine. The system was ground tested for 250 hours as part of GE Aircraft Engines IR&D Optical Engine Program. Subsequently, two flight sensor systems were shipped for use on the FOCSI (Fiber Optic Control System Integration) Program. The optical harnesses, each with four optical probes, measure the exhaust gas temperature in a GE F404 engine.

Tregay, George W.; Calabrese, Paul R.; Finney, Mark J.; Stukey, K. B.

1994-10-01

324

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

Energy Technology Data Exchange (ETDEWEB)

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

Meisner, Gregory P; Yang, Jihui

2014-02-11

325

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

Science.gov (United States)

The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns. PMID:21126058

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

2011-01-01

326

Temperature detection in a gas turbine  

Science.gov (United States)

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.

Lacy, Benjamin; Kraemer, Gilbert; Stevenson, Christian

2012-12-18

327

New processes for the reduction and capture of mercury emissions in the exhaust gas treatment; Neue Verfahren zur Minderung und Erfassung von Quecksilber-Emissionen in der Abgasbehandlung  

Energy Technology Data Exchange (ETDEWEB)

The highly volatile heavy metal mercury is deemed to be very toxic. There exist a lot of natural as well as anthropogenic sources for the pollution of the environment with mercury such as the coal-fired power generation, the electrolytic production of chlorine, the cement burning including the release of mercury from the cement raw meal, the waste incineration and the artisanal production of gold by amalgamation with liquid mercury. The authors of the contribution under consideration report on new procedures for the reduction and capture of mercury emissions in the exhaust gas treatment. The bromine supported precipitation of mercury in the exhaust gas treatment is an efficient and economic process which takes account of the future requirements of lower limit values for mercury. Simultaneously, a new measurement technique for a continuous capture of mercury with new standards on detection sensitivity, accuracy and reliability in connection with a more simple and cost-effective maintenance is developed. The bromine supported precipitation as well as the continuous capture of mercury are trendsetters and are actually the best available technologies for the reduction of mercury emissions.

Boness, Michael [Sick Maihak GmbH, Meersburg (Germany); Kanefke, Rico [Currenta GmbH und Co. OHG, Leverkusen (Germany). Sonderabfallverbrennung Leverkusen; Vosteen, Bernhard W. [Vosteen Consulting GmbH, Koeln (Germany)

2013-03-01

328

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

Science.gov (United States)

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.

Maqsood, Omar Shahzada

329

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)

330

A new algorithm predicts pressure and temperature profiles of gas/gas-condensate transmission pipelines  

Energy Technology Data Exchange (ETDEWEB)

The main objective of the present study has been the development of a relatively simple analytical algorithm for predicting flow temperature and pressure profiles along the two-phase, gas/gas-condensate transmission pipelines. Results demonstrate the ability of the method to predict reasonably accurate pressure gradient and temperature gradient profiles under operating conditions. (author)

Mokhatab, Saied [OIEC - Oil Industries' Engineering and Construction Group, Tehran (Iran, Islamic Republic of); Vatani, Ali [University of Tehran (Iran, Islamic Republic of)

2003-07-01

331

Fuel arrangement for high temperature gas cooled reactor  

International Nuclear Information System (INIS)

Disclosed is a fuel arrangement for a high temperature gas cooled reactor including fuel assemblies with separate directly cooled fissile and fertile fuel elements removably inserted in an elongated moderator block also having a passageway for control elements

332

Nitrogen charge temperature prediction in a gas lift valve  

Directory of Open Access Journals (Sweden)

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.

Marcelo M. Ganzarolli

2010-03-01

333

Isolating Gas Sensor From Pressure And Temperature Effects  

Science.gov (United States)

Two-stage flow system enables oxygen sensor in system to measure oxygen content of low-pressure, possibly-high-temperature atmosphere in test environment while protecting sensor against possibly high temperature and fluctuations in pressure of atmosphere. Sensor for which flow system designed is zirconium oxide oxygen sensor sampling atmospheres in high-temperature wind tunnels. Also adapted to other gas-analysis instruments that must be isolated from pressure and temperature effects of test environments.

Sprinkle, Danny R.; Chen, Tony T. D.; Chaturvedi, Sushi K.

1994-01-01

334

Metal oxide gas sensors upon various temperature-induced profiles  

Science.gov (United States)

This paper presents how an array of sensors with different sensitivities to gases can be applied for detection of hydrogen in the presence of humidity when operated upon various temperature - induced profiles. The sensors in the array are subject to temperature modulation over the range of 350 - 500°C. Temperature profiles are based on a cardinal sine as well as Meyer wavelet phi and psi functions. Changes in the sensor operating temperature lead to distinct resistance patterns of the sensors depending on gas concentration. The sensors responses are studied as a function of target gas concentration (0 - 3000 ppm) and relative humidity level (0 - 75%Rh). Feedforward back-propagation neural networks are used in order to facilitate gas concentration and humidity level prediction. The results show reliable hydrogen detection upon temperature modulation and a reduction of the total power consumption.

Gwi?d?, Patryk; Brudnik, Andrzej; Zakrzewska, Katarzyna

2014-08-01

335

Development of multipurpose high temperature gas reactors and materials  

International Nuclear Information System (INIS)

It is considered that multipurpose high temperature gas reactors will bear an important part in energy supply in Japan from the end of this century to the next century. Nuclear power generation can supply only 30% of the total energy consumed in Japan, therefore in order to substitute the energy supplied by petroleum now with atomic energy, the multipurpose high temperature gas reactors have been developed, which supply heat sources to iron and steel making and chemical industries, and produce hydrogen from water to use as the fuel for future. The high temperature gas reactors use graphite as the moderator and helium as the coolant because both materials are stable at high temperature. The outlet temperature of the reactors will be raised to 1000 deg. C, attempting to improve the efficiency of heat utilization. In order to produce the reducing gas for iron making, the experimental reactor of 50 MW thermal output and the outlet temperature of 1000 deg. C are required. The cooling system, the reactor construction, fuel and heat resistant metallic materials are explained. As the heat utilization system of multipurpose high temperature gas reactors, nuclear iron making and its system, and the themes of researches are described. The state of development of HTGRs in foreign countries and the international cooperation are reported. (Kako, I.)

336

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

Directory of Open Access Journals (Sweden)

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.

A. Rashid A. Aziz

2011-01-01

337

Nitrogen charge temperature prediction in a gas lift valve  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2010-01-01

338

46 CFR 182.430 - Engine exhaust pipe installation.  

Science.gov (United States)

...182.430 Engine exhaust pipe installation. (a...come in contact with an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly...normal conditions. (d) Pipes used for wet exhaust...

2010-10-01

339

46 CFR 119.430 - Engine exhaust pipe installation.  

Science.gov (United States)

...119.430 Engine exhaust pipe installation. (a...come in contact with an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly...normal conditions. (d) Pipes used for wet exhaust...

2010-10-01

340

A Smart Gas Sensor Insensitive to Humidity and Temperature Variations  

Science.gov (United States)

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

Hajmirzaheydarali, Mohammadreza; Ghafarinia, Vahid

2011-02-01

 
 
 
 
341

Excitations of a dense charged Bose gas at finite temperatures  

Science.gov (United States)

We discuss the finite temperature excitation spectrum in a dense charged Bose-condensed gas (CBG), which is of interest in connection with the new high transition temperature oxide superconductors. The free Bose gas (RPA), and the 1-loop approximations for the proper, irreducible quantities are examined. We point out that while the plasmon excitation frequency is essentially temperature-independent in a dense CBG, its weight as a pole of the single particle Green functions decreases with the condensate fraction n0( T). At the same time, as the temperature increases, the single particle spectral weight shifts to strongly damped single-particle modes, which become free particles at Tc. Thus we conclude that, in contrast to a dilute weakly interacting Bose gas with short-range interactions, the excitation spectrum of a CBG is more analogous to that in superfluid 4He.

Griffin, A.

1988-08-01

342

Design and development of gas turbine high temperature reactor 300  

International Nuclear Information System (INIS)

JAERI (Japan Atomic Energy Research Institute) has been designing a Japan's original gas turbine high temperature reactor, GTHTR300 (Gas Turbine High Temperature Reactor 300). The greatly simplified design based on salient features of the HTGR (High Temperature Gas-cooled reactor) with a closed helium gas turbine enables the GTHTR300 a high efficient and economically competitive reactor to be deployed in early 2010s. Also, the GTHTR300 fully taking advantage of various experiences accumulated in design, construction and operation of the HTTR (High Temperature Engineering Test Reactor) and fossil gas turbine systems reduces technological development concerning a reactor system and electric generation system. Original features of this system are core design with two-year refueling interval, conventional steel material usage for a reactor pressure vessel, innovative plant flow scheme and horizontally installed gas turbine unit. Due to these salient features, the capital cost of the GTHTR300 is less than a target cost of 200 thousands Yen/kWe, and the electric generation cost is close to a target cost of 4 Yen/kWh. This paper describes the original design features focusing on reactor core design, fuel design, in-core structure design and reactor pressure vessel design except PCU design. Also, R and D for developing the power conversion unit is briefly described. The present study is entrusted from the Ministry of Education, Culture, Sports, Science and Technology of Japane, Sports, Science and Technology of Japan. (author)

343

Bimodular high temperature planar oxygen gas sensor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A bimodular planar O2 sensor was fabricated using NiO nanoparticles (NPs) thin film coated yttria-stabilized zirconia (YSZ) substrate. The thin film was prepared by radio frequency (r.f.) magnetron sputtering of NiO on YSZ substrate, followed by high temperature sintering. The surface morphology of NiO nanoparticles film was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). X-ray diffraction (XRD) patterns of NiO NPs thin film before and after high tempera...

YuLei; HaiyongGao; PuxianGao

2014-01-01

344

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

345

ULTRASENSITIVE HIGH-TEMPERATURE SELECTIVE GAS DETECTION USING PIEZOELECTRIC MICROCANTILEVERS  

Energy Technology Data Exchange (ETDEWEB)

We have obtained very promising results in the Phase I study. Specifically, for temperature effects, we have established that piezoelectric cantilever sensors could retain their resonance peak strength at high temperatures, i.e., the Q values of the resonance peaks remained above 10 even when the temperature was very close to the Curie temperature. This confirms that a piezoelectric cantilever sensor can be used as a sensor up to its Curie temperature. Furthermore, we have shown that the mass detection sensitivity remained unchanged at different temperatures. For selective gas detection, we have demonstrated selective NH{sub 3} detection using piezoelectric cantilever sensors coated with mesoporous SiO{sub 2}. For high-temperature sensor materials development, we have achieved highly oriented Sr-doped lead titanate thin films that possessed superior dielectric and ferroelectric properties. Such highly oriented films can be microfabricated into high-performance piezoelectric microcantilever sensors that can be used up to 490 C. We have accomplished the goal of Phase I study in exploring the various aspects of a high-temperature gas sensor. We propose to continue the study in Phase II to develop a sensor that is suitable for high-temperature applications using piezoelectrics with a high Curie temperature and by controlling the effects of temperature. The lead titanate based thin film developed in Phase I is good for applications up to 490 C. In phase II, we will develop lithium niobate thin film based cantilevers for applications up to 1000 C.

Wan Y. Shih; Tejas Patil; Qiang Zhao; Yi-Shi Chiu; Wei-Heng Shih

2004-03-05

346

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.

347

Partially integrated exhaust manifold  

Energy Technology Data Exchange (ETDEWEB)

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.

Hayman, Alan W; Baker, Rodney E

2015-01-20

348

High temperature water gas shift catalysts: a computer modelling study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The high-temperature (HT) Water Gas Shift (WGS) reaction has considerable technological relevance for lowering CO content during the conversion of natural gas or liquid hydrocarbons to hydrogen. Conventional HT-WGS catalysts based on oxides of iron and chromium are well established industrially. However, it is crucial to remove any impurities present such as Cr6+, S or N during the catalytic process. In particular, Cr6+ is regarded as a Class I carcinogen and its presence is re...

Benny, S.

2010-01-01

349

Experimental study of gas turbine combustion with elevated fuel temperatures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 w...

Wiest, Heather K.

2013-01-01

350

Finite temperature stability of a trapped dipolar Bose gas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We calculate the stability diagram for a trapped normal Bose gas with dipole-dipole interactions. Our study characterizes the roles of trap geometry, temperature, and short-ranged interactions on the stability. We predict a robust double instability feature in oblate trapping geometries arising from the interplay of thermal gas saturation and the anisotropy of the interaction. Our results are relevant to current experiments with polar molecules and will be useful in developi...

Bisset, R. N.; Baillie, D.; Blakie, P. B.

2011-01-01

351

A study on the concentration of CO by the length and the variation of the bent tube of the exhaust pipe for a household gas boiler  

International Nuclear Information System (INIS)

Energy and environment become increasingly serious after the industrial revolution. The demand for gas as an ecofriendly energy source is also increasing. With the demand, the installation and the use of gas boilers have also increased, so the damage to human life by the waste gas (CO and CO2) continues increasing every year. Hence, the aim of this study was to investigate the concentration of CO (Carbon Monoxide) by the length and the variation of the bent tube of the exhaust pipe by installing a boiler with the same method as a household boiler and to discover the harm to humans. For the effect of the length, the allowable concentration of CO is 50ppm, and the 3m of the once bent tube starts exceeding the allowable concentration of CO after 5 minutes, and the 4m and 5m starts exceeding after 3 minutes. In addition, the 1m of three times bent tube starts exceeding the allowable concentration of CO after 3 minutes

352

Gravitational collapse of a magnetized fermion gas with finite temperature  

Science.gov (United States)

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 f ˜10-6 and T/ m f ˜10-3.

Delgado Gaspar, I.; Pérez Martínez, A.; Sussman, Roberto A.; Ulacia Rey, A.

2013-07-01

353

Gravitational collapse of a magnetized fermion gas with finite temperature  

CERN Document Server

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

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

2013-01-01

354

Gravitational collapse of a magnetized fermion gas with finite temperature  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

355

High-temperature oxidation of graphite rods with temperature control by combustion gas recycle  

International Nuclear Information System (INIS)

The combustion of graphite (fuel blocks) is of fundamental importance in the fuel reprocessing scheme for the High-Temperature Gas-Cooled Reactor (HTGR). A study was made to evaluate a chunk-type burner for possible application in this reprocessing step. The combustion gases were recycled to allow operation at higher burn rates without an increase in graphite temperature. Graphite rods of two diameters were oxidized with makeup oxygen and recycled stack gases at various gas flow rates in an insulated reactor. Results of this study indicate a strong dependence of oxygen transfer on gas flow rate with little effect resulting from changes in graphite temperature. High carbon monoxide concentrations in the exit gas were not a problem except at oxygen concentrations below approx. 5%. Stable operation of a recycle controlled burner was achieved, avoiding the temperature excursions common in previous graphite burners

356

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

Science.gov (United States)

...and associated valves, pressure and temperature...engines; see “Calculation of Emissions and...and associated valves, pressure and temperature...engines; see “Calculation of Emissions and...measured. (ii) Calculation of the CVS flow...controllers, metering valves, separate...

2010-07-01

357

Materials for high temperature gas-cooled reactors  

Energy Technology Data Exchange (ETDEWEB)

The main components of high temperature gas-cooled reactors, for which heat resistant alloys are used, are high temperature structural materials such as the heating tubes of intermediate heat exchangers and the liners of pipings and the material for cladding control rods. In this report, only the heat resistant alloys for high temperature structures, which involve many material engineering problems peculiar to high temperature gas-cooled reactors, are described. The main characteristics generally considered in the heat resistant alloys used for high temperature structures are creep and creep rupture characteristics, high cycle and low cycle fatigue, creep-fatigue interaction, the effect of thermal ageing on short time properties, creep ratchet characteristics, creep buckling characteristics, and the environmental effect by helium containing impurities of a minute amount. The heat resistant alloys which approach the condition of the practical use for high temperature structures are Alloy 800 H for 800-850 deg C, Hastelloy XR for 900-950 deg C and Inconel 617 for 950 deg C. The present state of developing high performance materials in various countries is reported. Also the examples of using graphite and carbon materials for high temperature gas-cooled reactors are described. (K.I.).

Nakajima, Hajime; Oku, Tatsuo (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

1990-04-01

358

Materials for high temperature gas-cooled reactors  

International Nuclear Information System (INIS)

The main components of high temperature gas-cooled reactors, for which heat resistant alloys are used, are high temperature structural materials such as the heating tubes of intermediate heat exchangers and the liners of pipings and the material for cladding control rods. In this report, only the heat resistant alloys for high temperature structures, which involve many material engineering problems peculiar to high temperature gas-cooled reactors, are described. The main characteristics generally considered in the heat resistant alloys used for high temperature structures are creep and creep rupture characteristics, high cycle and low cycle fatigue, creep-fatigue interaction, the effect of thermal ageing on short time properties, creep ratchet characteristics, creep buckling characteristics, and the environmental effect by helium containing impurities of a minute amount. The heat resistant alloys which approach the condition of the practical use for high temperature structures are Alloy 800 H for 800-850 deg C, Hastelloy XR for 900-950 deg C and Inconel 617 for 950 deg C. The present state of developing high performance materials in various countries is reported. Also the examples of using graphite and carbon materials for high temperature gas-cooled reactors are described. (K.I.)

359

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

1997-05-01

360

Emission of carcinogenic components with automobile exhausts.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Different sampling methods for mutagenic polynuclear aromatic hydrocarbons (PAH) are described. These methods involve either direct sampling of raw exhausts which prior to filtering are cooled in a condenser, or filter sampling of exhausts diluted in a tunnel. The relevance of gas-phase PAHs of samples from diluted exhausts is discussed; methods used are either adsorbents (XAD-2) or cryogenic condensation. The emission of benzo(a)pyrene and certain other PAHs is reported from vehicles using d...

Stenberg, U.; Alsberg, T.; Westerholm, R.

1983-01-01

 
 
 
 
361

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.

362

AGRs and high-temperature gas-cooled reactors  

International Nuclear Information System (INIS)

Gas cooled reactors have good safety and environmental features with small active effluents and low thermal pollution. The two most important coolant gases are carbon dioxide, which is dense and cheap and used in the AGR type reactors, and helium which is costly, but inert, and used in the high temperature type (HTR). The historical development and essential features of the AGR and the HTR are summarised. Hinkley B and Hunterston B reactors are used to illustrate the AGR type, Fort St. Vrain the HTR type. In Germany the pebble-bed concept has been developed and a thorium high temperature reactor (THTR) built. Details of design features are given. Gas-cooled fast reactors have been studied but are as yet still theoretical. The technology of gas-cooled reactors is versatile. This has meant that designs have not converged and no single strong line has emerged worldwide. (U.K.)

363

DEVELOPMENT AND TESTING OF AN AMMONIA REMOVAL UNIT FROM THE EXHAUST GAS OF A MANURE DRYING SYSTEM  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The storage and handling of animal wastes is one of the main sources of ammonia gas emissions. Ammonia gas has a distinct, unpleasant odor and can become detrimental to the health of humans and animals at high concentrations. Ammonia emissions are of particular concern in manure drying systems, where large losses of nitrogen, in the form of ammonia can cause air quality concerns. The aim of this study was to develop an ammonia removal system for a poultry manure drying system. The thin layer ...

Ghaly, A. E.; Macdonald, K. N.

2013-01-01

364

A review of helium gas turbine technology for high-temperature gas-cooled reactors  

International Nuclear Information System (INIS)

Current High-Temperature Gas-cooled Reactors (HTGRs) are based on a closed brayton cycle with helium gas as the working fluid. Thermodynamic performance of the axial-flow helium gas turbines is of critical concern as it considerably affects the overall cycle efficiency. Helium gas turbines pose some design challenges compared to steam or air turbomachinery because of the physical properties of helium and the uniqueness of the operating conditions at high pressure with low pressure ratio. This report present a review of the helium Brayton cycle experiences in Germany and in Japan. The design and availability of helium gas turbines for HTGR are also presented in this study. We have developed a new throughflow calculation code to calculate the design-point performance of helium gas turbines. Use of the method has been illustrated by applying it to the GTHTR300 reference

365

Thermal Creep Flow of Helium Gas at Cryogenic Temperatures  

Science.gov (United States)

We present a molecular dynamics (MD) simulation of nanoscale gas flow due to thermal creep at cryogenic temperatures. Helium is considered because its low liquefying temperature allows a wide range of cryogenic analysis. The thermal creep flow along a nanochannel is generated by applying temperature differences along the channel. Pressure and density variations are measured at various rarefaction conditions, covering the slip flow to the free molecular regimes. Thermo molecular pressure difference (TMPD) values are also calculated. Our results are compared with those in the literature.

Babac, G.; Reese, J. M.

2014-03-01

366

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1999-08-01

367

Electron density and temperature of gas-temperature-dependent cryoplasma jet  

International Nuclear Information System (INIS)

A microsize cryoplasma jet was developed and analyzed at plasma gas temperatures ranging from room temperature down to 5 K. Experimental results obtained from optical emission spectroscopy and current-voltage measurements indicate that the average electron density and electron temperature of the cryoplasma jet depend on the gas temperature. In particular, the electron temperature in the cryoplasma starts to decrease rapidly near 60 K from about 13 eV at 60 K to 2 eV at 5 K, while the electron density increases from about 109 to approximately 1012 cm-3 from room temperature to 5 K. This phenomenon induces an increase in the Coulomb interaction between electrons, which can be explained by the virial equation of state.

368

Discussion of the effects of recirculating exhaust air on performance and efficiency of a typical microturbine  

International Nuclear Information System (INIS)

This paper reports on a specific phenomenon, noticed during steam injection experiments on a microturbine. During the considered experiments, measurements indicated an unsteady inlet air temperature of the compressor, resulting in unstable operation of the microturbine. Non-continuous exhaust air recirculation was a possible explanation for the observed behaviour of the microturbine. The aim of this paper is to investigate and demonstrate the effects of exhaust recirculation on a microgasturbine. Depending on wind direction, exhaust air re-entered the engine, resulting in changing inlet conditions which affects the operating regime of the microturbine. For this paper, a series of experiments were performed in the wind tunnel. These series of experiments allowed investigation of the effect of the wind direction on flue gasses flow. Next to the experiments, steady-state simulations of exhaust recirculation were performed in order to study the effect of exhaust recirculation on thermodynamic performance of the microturbine. Dynamic simulations of the non-continuous recirculation revealed the effects of frequency and amplitude on average performance and stability. Results from simulations supported the important impact of exhaust recirculation. Wind tunnel tests demonstrated the influence of the wind direction on recirculation and revealed the necessity to heighten the stack, thus preventing exhaust recirculation. -- Highlights: ? Unstable operation of a T100 microturbine during steam injection tests was noticed, caused by exhaust gas recirculation. ? Wind tunnel tests were performed to study the effect of the wind direction on the recirculation process. ? Steady-state simulations to investigate the effect of exhaust gas recirculation on thermodynamic performance. ? Dynamic simulations to reveal effects of frequency and amplitude on average performance and stability. ? Wind tunnel tests revealed the necessity to heighten the stack to prevent exhaust recirculation.

369

Development of automatic air intake door control system for exhaust gas. Prevention of contaminated air by controlling A/C air intake door; Haiki gas taio auto naigaiki system no kaihatsu. Eakon suikomiguchi seigyo ni yoru haiki gas no shashitsunai eno shinnyu boshi  

Energy Technology Data Exchange (ETDEWEB)

Thermal comfort in the cabin of vehicle is upgraded by developing the climate control system Passengers must control the intake door of air conditioner to reduce entering Exhaust Gas into the cabin. This paper is concerned with development the automatic intake door control system to acquire high comfort performance of passengers. 8 figs., 1 tab.

Honda, Y.; Samukawa, K. [Denso Corp., Aichi (Japan)

1997-10-01

370

An electrochemical denitrification of exhaust gases and direct thermoelectric gas sensors. Examples of innovative applications of solid ionic conductors; Elektrochemische Entstickung von Abgasen und direkte thermoelektrische Gassensoren. Beispiele fuer neuartige Anwendungen von Feststoff-Ionenleitern  

Energy Technology Data Exchange (ETDEWEB)

In this study, novel applications of ion conductors were investigated: Firstly the electrochemical NO{sub x} removal in exhaust gases, i.e. the reduction of nitrogen oxides by decomposing it with an ion conductor. Secondly, direct thermoelectric gas sensors on the basis of a solid ion conductor. In the case of electrochemical NO{sub x} removal, nitrogen oxides should be decomposed by applying a voltage to an oxygen ion conductor and the resulting oxygen ions should be pumped through the ion conductor, resulting in oxygen and nitrogen. As an alternative, water can be decomposed electrochemically by applying a voltage to a proton conductor so that hydrogen forms, which is a reducing agent for nitrogen oxides. To improve the efficiency of this method in exhausts with oxygen excess, it should be combined with a NO{sub x} storage catalyst, which is then intended to be regenerated electrochemically. Here, the aim was to investigate the feasibility of this idea. Therefore, the NO{sub x} reduction behaviour of several oxygen ion and proton conductors was measured. The storage capability of different NO{sub x} storage catalyst materials at higher temperatures was determined. Furthermore, the combination of storage material and ion conductor was investigated to show that the storage material can be regenerated electrochemically. This was then also verified in a model system with an additional diffusion barrier. Accompanying to the tests, the concentration distribution was simulated to improve the interpretation of the measurement results. It could be shown that the electrochemical regeneration of a NO{sub x} storage material is principally possible, both with oxygen ion and proton conductors. However, an improvement of the current efficiency could not be proven. Direct thermoelectric gas sensors measure the thermopower of a material that depends on the gas atmosphere. Here, ion conductors were investigated as gas sensitive material. Firstly, an oxygen ion conductor, doped zirconia, was used. The thermopower of zirconia is well known. In this part of the study, the aim was to use the oxygen dependency of the thermopower of a cell consisting of zirconia and platinum electrodes for an oxygen sensor. An appropriate sensor was manufactured in thick film technology and measured. It was demonstrated that the sensor, as expected according to theory, has a semilogarithmic characteristic. The sensor also showed a low cross-sensitivity to other gases and a low temperature dependency. Nevertheless, the sensor was tending to age especially at higher temperatures, which become apparent by a change of the measurement signal. Astonishingly, the sensor worked only in lean atmospheres, not in rich ones. Superposition of the thermovoltage by a Nernst voltage was found to be the cause of this. Additionally, the thermopower of different proton conductors was investigated. Here, the main focus was on measuring the hydrogen partial pressure dependency of the thermopower. It could be shown that this dependency is semilogarithmic for all proton conductors that were tested. For proton conductors where the protons are not part of the regular lattice but lattice defects, the difficulty is the change of the charge carrier concentration depending on the oxygen and water concentration in the gas atmosphere. Consequently the slope of the characteristic changes too, which makes an application as sensor difficult. Therefore, proton conductors where the protons are part of the lattice, solid acids in this case, where also investigated. Their slope of the characteristic was near to the expected theoretic value. (orig.)

Roeder-Roith, Ulla

2012-07-01

371

Analysis using thin layer and gas-liquid chromatography of polycyclic aromatic hydrocarbons in the exhaust products from a European car running on fuels containing a range of concentrations of these hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

The present investigation relates the PAH content of four unleaded fuels at constant level of aromatics (48 percent) but with increasing concentration of aromatic hydrocarbons with 9-10+ carbon atoms (0; 1; 15; 46 percent) to the PAH content of the exhaust products when burnt in a European car. The simplified and rapid analytical analysis of fuels and exhaust products involved partition between solvents, thin layer chromatography and gas-liquid chromatography. The results showed that the amount of PAH in the fuels tested, increases with an increase in the concentration of C/sub 9/-C/sub 10//sub +/ aromatics. The PAH content of the exhaust gases increased with increasing content of PAH in the respective fuels, but it was not possible to ascertain whether it was the PAH content of the fuels or the C/sub 9/-C/sub 10/ and higher aromatic hydrocarbons content which was the more important factor.

Candeli, A. (Univ. of Perugia, Italy); Morozzi, G.; Paolacci, A.; Zoccolillo, L.

1975-09-01

372

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)

373

Finite-temperature stability of a trapped dipolar Bose gas  

International Nuclear Information System (INIS)

We calculate the stability diagram for a trapped normal Bose gas with dipole-dipole interactions. Our study characterizes the roles of trap geometry, temperature, and short-range interactions on the stability. We predict a robust double instability feature in oblate trapping geometries arising from the interplay of thermal gas saturation and the anisotropy of the interaction. Our results are relevant to current experiments with polar molecules and will be useful in developing strategies to obtain a polar molecule Bose-Einstein condensate.

374

Gas temperature, electron density and electron temperature measurement in a microwave excited microplasma  

Energy Technology Data Exchange (ETDEWEB)

Gas temperature, electron density and electron temperature of a microwave excited microplasma are measured by optical emission spectroscopy. This microplasma is generated in the small gap of a microstrip split-ring resonator in argon at near atmospheric pressure. When less than 100 ppm of water is present in the plasma, the gas temperature can be obtained from the rotational temperature of the hydroxyl molecule (A {sup 2}{sigma}{sup +}, v = 0) and the electron density can be measured by the Stark broadening of the hydrogen Balmer {beta} line. According to a collisional-radiative model, the electron temperature can be estimated from the measured excitation temperature of argon 4p and 5p levels. It is found that the values of these parameters (gas temperature, electron density and temperature) increase when the gap width of the resonator is reduced. However, when the microwave power increases, these parameters, especially the electron density, do not vary significantly. Discussions on this phenomenon, being very different from that in the low-pressure bounded discharges, are provided.

Zhu Ximing; Chen Wencong; Pu Yikang [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)], E-mail: puyikang@tsinghua.edu.cn

2008-05-21

375

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)

376

Automobile Exhaust Pollution and Purification Methods  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Tang, Dawei

2014-01-01

377

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

Science.gov (United States)

...assembly, heat exchanger...associated valves, pressure and...preventing loss of sample...after the heat exchanger, shall...see “Calculation of Emissions...associated valves, pressure and temperature...preventing loss of sample...without a heat exchanger...see “Calculation of...

2010-07-01

378

Room temperature hydrogen gas sensitivity of nanocrystalline pure tin oxide.  

Science.gov (United States)

Nanocrystalline (6-8 nm) tin oxide (SnO2) thin film (100-150 nm) sensor is synthesized via sol-gel dip-coating process. The thin film is characterized using focused ion-beam microscopy (FIB) and high-resolution transmission electron microscopy (HRTEM) techniques to determine the film thickness and the nanocrystallite size. The utilization of nanocrystalline pure-SnO2 thin film to sense a typical reducing gas such as hydrogen, at room temperature, is demonstrated in this investigation. The grain growth behavior of nanocrystalline pure-SnO2 is analyzed, which shows very low activation energy (9 kJ/mol) for the grain growth within the nanocrystallite size range of 3-20 nm. This low activation energy value is correlated, via excess oxygen-ion vacancy concentration, with the room temperature hydrogen gas sensitivity of the nanocrystalline pure-SnO2 thin film sensor. PMID:15112557

Shukla, S; Seal, S

2004-01-01

379

Gas diffusion and temperature dependence of bubble nucleation during irradiation  

DEFF Research Database (Denmark)

The continuous production of gases at relatively high rates under fusion irradiation conditions may enhance the nucleation of cavities. This can cause dimensional changes and could induce embrittlement arising from gas accumulation on grain boundaries. Computer calculations have been made of the diatomic nucleation of helium bubbles, assuming helium to diffuse substitutionally, with radiation-enhanced diffusion at lower temperatures. The calculated temperature dependence of the bubble density shows excellent agreement with that observed in 600 MeV proton irradiations, including a reduction in activation energy below Tm/2. The coalescence of diatomic nuclei due to Brownian motion markedly improves the agreement and also provides a well-defined terminal density. Bubble nucleation by this mechanism is sufficiently fast to inhibit any appreciable initial loss of gas to grain boundaries during the nucleation period, provided that incubation effects do not occur.

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

1986-01-01

380

Crystallization of silicon nanoclusters with inert gas temperature control  

Science.gov (United States)

We analyze the fundamental process of crystallization of silicon nanoclusters by means of molecular dynamics simulations, complemented by magnetron-sputter inert gas condensation, which was used to synthesize polycrystalline silicon nanoclusters with good size control. We utilize two well-established Si interatomic potentials: the Stillinger-Weber and the Tersoff III. Both the simulations and experiments show that upon cooling down by an Ar gas thermal bath, initially liquid, free-standing Si nanocluster can grow multiple crystal nuclei, which drive their transition into polycrystalline solid nanoclusters. The simulations allow detailed analysis of the mechanism, and show that the crystallization temperature is size-dependent and that the probability of crystalline phase nucleation depends on the highest temperature the cluster reaches during the initial condensation and the cooling rate after it.

Zhao, Junlei; Singh, Vidyadhar; Grammatikopoulos, Panagiotis; Cassidy, Cathal; Aranishi, Kengo; Sowwan, Mukhles; Nordlund, Kai; Djurabekova, Flyura

2015-01-01

 
 
 
 
381

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

382

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

International Nuclear Information System (INIS)

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

383

Dissertation on a direct injection Diesel process with automatic control, dependent on load, of the ratio of the fuel adhering to the walls to that distributed in the air, with particular attention to exhaust gas turbo-supercharging and exhaust gas feedback. Ueber ein direkteinspritzendes Dieselverfahren mit selbsttaetiger, lastabhaengiger Steuerung des Verhaeltnisses von wandangelagertem zu luftverteiltem Kraftstoffanteil unter besonderer Beruecksichtigung der Abgasturboaufladung und Abgasrueckfuehrung  

Energy Technology Data Exchange (ETDEWEB)

The development of modern engines is marked by the conventional requirements for high output with as small a size as possible and low fuel consumption and a reduction of the emission of poisonous exhaust gases and low combustion noise. A newly developed direct injection Diesel combustion process is introduced as a contribution to fulfilling these requirements. In order to be able to combine the advantages of the two different forms of direct injection combustion, i.e., with the fuel distributed in the air and adhering to the walls, one is aiming at a process of combustion where the fuel clings like a film to the walls of the combustion chamber at full load, but is distributed over the air automatically with decreasing load, i.e., without external manipulation of controls, without showing the Diesel engine ignition knocking of conventional direct injection engines. Measures to improve the exhaust gas were of particular interest. The results of the investigations on a first low-speed experimental engine were transposed to a modern engine.

Melzer, H.H.

1981-08-31

384

A microbearing gas flow with different walls´ temperatures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An analytical solution for the non-isothermal two-dimensional compressible gas flow in a slider microbearing with different temperatures of walls is presented in this paper. The slip flow is defined by the continuity, Navier-Stokes and energy continuum equations, along with the velocity slip and the temperature jump first order boundary conditions. Knudsen number is in the range of 10-3-10-1, which corresponds to the slip flow. The ratio between the exit microbearing height and the micr...

Mili?ev Snežana S.; Stevanovi? Nevena D.

2012-01-01

385

Multiphysics methods development for high temperature gas reactor analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Seker, Volkan

2007-01-01

386

Use of room temperature ionic liquids in gas sensor design.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The attainable steady-state limiting currents and time responses of membrane-covered and membrane-independent gas sensors incorporating different electrode and electrolyte materials have been compared. A new design comprising a membrane-free microelectrode modified with a thin layer of a room temperature ionic liquid is considered. While the use of ionic liquid as electrolyte eliminates the need for a membrane and added supporting electrolyte, the slower diffusion of analyte within the more v...

Buzzeo, Mc; Hardacre, C.; Compton, Rg

2004-01-01

387

Gearbox Scheme in High Temperature Reactor Helium Gas Turbine System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Sheng Liu; Xuanyu Sheng

2012-01-01

388

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2013-01-01

389

Utilizing the response patterns of a temperature modulated chemoresistive gas sensor for gas diagnosis  

Energy Technology Data Exchange (ETDEWEB)

The observed features in the temporal response patterns of a temperature-modulated chemoresistive gas sensor were used for gas diagnosis. The patterns were recorded for clean air and air contaminated with different levels of some volatile organic compounds while a staircase heating voltage waveform had been applied to the microheater of a tin oxide gas sensor that modulated its operating temperature. Combining the steady-state and transient parameters of the recorded responses in the 50-400 deg. C range resulted in discriminatory feature vectors which were utilized for contaminant classification. The information content of these feature vectors was proved sufficient for discrimination of methanol, ethanol, 1-butanol, and acetone contaminations in a wide concentration range.

Amini, Amir [Jannatabad College, Sama Organization, Islamic Azad University, Tehran (Iran, Islamic Republic of); Ghafarinia, Vahid, E-mail: amir.amini.elec@gmail.com, E-mail: ghafarinia@ee.kntu.ac.ir [Electrical Engineering Department, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

2011-02-15

390

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.

391

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

392

Mixing Characteristics Downstream of Core Region of High-Temperature Axisymmetric Jets Exhausting Into Transonic and Supersonic Streams  

Science.gov (United States)

A series of rocket motors with varying exit to throat area ratios was tested in the 8- by 6-foot wind tunnel to determine the effects of mixing on jet diameter and temperature decay at large distances (x/d > 30) from the nozzle exit. An approximate method to account for effects of the initial expansion was evolved. It was determined that the combustion efficiency has an important effect on jet spreading, since the unburned products can burn downstream of the nozzle. The data showed considerable scatter; however, mixing rates were, in general, lower than those observed for subsonic jets. Data for angles of attack of 5 and 10 deg are also presented, giving the respective centerline shift and temperature decay as a function of axial distance.

Huff, Ronald G.; Abdalla, Kaleel L.

1960-01-01

393

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.)

394

Design of indirect gas turbine cycle for a modular high temperature gas cooled reactor  

International Nuclear Information System (INIS)

This paper describes a design of the indirect gas turbine cycle for the 200MWt pebble bed MHTGR. In the design, the helium out of the Intermediate Heat eXchanger (IHX) is extracted to a small RPV cooling system. The gas flows through a small RPV recuperator and is cooled down, then it is used to cool the RPV. The whole primary circuit is integrated in a pressure vessel. The core inlet/outlet temperatures are 550 deg. C/900 deg. C, which can supply a gas heat source of 500 deg. C/850 deg. C in the secondary side. The heat source could be used to drive a nitrogen gas turbine cycle and a plant busbar electricity generation efficiency of about 48% is estimated. The thermodynamic calculation, preliminary design of the system components, and the important accident analysis are described in this paper. (author). 5 refs, 3 figs, 4 tabs

395

Mode of operation of a fuel cell system with an open anode and exhaust gas catalyst in a vehicle traction system; Betriebsweise eines Brennstoffzellensystems mit offener Anode und Abgaskatalysator in einem automobilen Antriebssystem  

Energy Technology Data Exchange (ETDEWEB)

The author of the contribution under consideration reports on the dynamic operation of a fuel cell system with an open anode and exhaust gas catalyst in a vehicle traction system. In comparison to known automobile fuel cell system the architecture of the fuel cell system described here is considerably simplified. This is due to the fact that there is any recirculation of hydrogen. After mixing, the residual hydrogen is transformed with the exhaust gas of the cathode room in a catalytic reactor. This results in a cost savings and an enhanced power density of the propulsion system. In the anode room of the fuel cell, the omission of the recirculation results in a near-dead-end operation. Finally an operation strategy is developed which avoids unfavourable operating conditions of the fuel cell system and enables an efficient operation of the power train. The effectivity of the operational mode is confirmed in different test cycles.

Dehn, Steffen

2012-11-01

396

30 CFR 36.25 - Engine exhaust system.  

Science.gov (United States)

...2010-07-01 false Engine exhaust system. 36.25 ...FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION... § 36.25 Engine exhaust system. (a) Construction...or discharge of heated particles to a surrounding flammable...positioned that only cooled exhaust gas will...

2010-07-01

397

High-Temperature Gas Sensor Array (Electronic Nose) Demonstrated  

Science.gov (United States)

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

Hunter, Gary W.

2002-01-01

398

Challenges on the way to noble gas temperatures on speleothems  

Science.gov (United States)

In the last years, speleothems gained importance as a paleoclimate archive. Nonetheless, so far no proxy in speleothems has really gained acceptance as a commonly used paleotemperature indicator. Application of the noble gas thermometer to speleothem fluid inclusions promises in principle the determination of absolute paleotemperatures. Kluge et al. (2008) and Scheidegger et al. (2010) showed that the precise measurement of noble gas concentrations on fluid inclusions is possible in general. Unfortunately, the extraction and measurement technique presented by Kluge et al. (2008) allowed the determination of reasonable noble gas temperatures (NGTs) only for some samples. Some of the problems which occurred as well as some (possible) solutions will be presented. A general problem for the application of the noble gas thermometer on speleothems is the presence of air-filled inclusions in the speleothem. Noble gases released from them mask the temperature signal of the noble gases dissolved in the water-filled inclusions. In order to reduce the air/water volume ratio, a stepwise extraction technique has been developed successfully. However, often the different extraction steps on one sample lead to temperatures that do not agree well with each other. Samples of the stalagmite H12 from Hoti Cave in Oman showed an excess in neon. A similar neon excess was found by Scheidegger et al. (2010) but for a larger number of samples. They suggest that helium and neon can be situated in voids between the atoms forming the carbonate lattice. However, a sample of stalagmite H12 showed neon excess in the very first extraction step, which is not expected for a matrix related component. The NGTs reported by Kluge et al. (2008) seemed to be 2 to 3 °C too low compared to independent temperature reconstructions. In order to investigate this offset and the overall accuracy of the extraction and measurement technique, tiny amounts of air-equilibrated water (AEW) were measured as test samples. In a first test with these so-called ?AEWs the heavier noble gases (Ar, Kr, Xe) seemed to be underestimated, while a second measurement run did not show this offset. Overall, these tests demonstrated the good reproducibility of better than 5% for the noble gas concentrations.

Marx, T.; Aeschbach-Hertig, W.

2012-04-01

399

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

Energy Technology Data Exchange (ETDEWEB)

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.

Lee O. Nelson

2011-04-01

400

Gas-Metal Reactions at High Temperature with Particular Reference to Niobium-Gas Systems  

International Nuclear Information System (INIS)

One of the most serious disadvantages to the use of niobium as a high temperature construction material is its relatively high reactivity with gases. When appreciable amounts of gases are dissolved in the metal lattice, the material becomes very brittle. The equilibrium states between the solid solution and gas phase can be studied effectively by gas- absorption and degassing experiments performed at high temperature and under low pressure. Under these conditions the reaction of nitrogen, oxygen and water vapour with niobium was evaluated gravimetrically and volumetrically. It was found that in the Nb-N system the condensed phases are in equilibrium with molecular nitrogen, whereas in the Nb-O system the gas phase consists of volatile oxides and the oxygen partial pressure can be neglected. In the Nb-N system equilibrium pressures were measured as a function of nitrogen concentration at temperatures between 1600 and 2200°C. Based upon these results, the p-T-c diagram for the metal-rich side of the system was established up to 30 at.% N and some thermodynamic data were calculated. In the Nb-O system evaporation rates of the volatile oxides were measured at temperatures between 1600 and 2300°C, under vacuum and in an oxygen or water vapour atmosphere at pressures of less than 10-2 torr. With presence of oxygen or water vapour a dynamic equilibrium was obtained, for a definite pressure and temperature range, between gas absorption and evaporation of volatiles absorption and evaporation of volatile oxides from the niobium-oxygen solid solution. Equations were established showing quantitative relationships between oxygen concentration, temperature and oxygen or water vapour pressure in dynamic equilibrium. In addition, the vapour pressure of the volatile oxides was determined, as were also the respective values of the activation energies of the gas-absorption and degassing reactions. From the oxygen to niobium ratio of the volatile component and from the dependence of this ratio on temperature and concentration it can be concluded that the oxides NbO and NbO2 evaporate. The thermodynamic data obtained for niobium-gas systems were compared with the corresponding values for tantalum, which show somilar behaviour with oxygen and nitrogen. (author)

 
 
 
 
401

A temperature and photographic time-series from a seafloor gas hydrate deposit on the Gulf of Mexico Slope  

Science.gov (United States)

Under laboratory conditions, gas hydrates are highly sensitive to changes in water temperature. MacDonald et al. (1994) and Roberts et al. (1999) have monitored in-situ deposits and recorded rapid changes in gas flux from vents partially plugged with gas hydrate; the changes appear to correlate with fluctuation in bottom temperature over ranges of <0.2 to 1.0 C. To study this process in a different way, a monitoring array consisting of a time lapse camera and two thermistor probes was deployed at a hydrocarbon seep known as Bush Hill. Every 6 hours for 96 days (until battery power was exhausted), the camera recorded a digital image of a prominent gas hydrate mound consisting of Structure II hydrate with gas vents, chemosynthetic tube worms, and a number of mobile species. The temperature probes comprised two autonomous Antares thermistors, one at each end of a 50-cm PVC wand, which recorded temperatures with precision of better than 0.1 C at 30-min intervals over 327 d. One probe was implanted with a tight seal into a drill hole about 7 cm deep in the top of the gas hydrate mound. The second was inserted about 50 cm deep into the adjacent sediments. For each probe, the top thermistor recorded the ambient water temperature while the bottom thermistor recorded the internal temperature of the hydrate or sediment. Photographic results show no dramatic changes in the size, shape, or gas venting from the mound during the 96 day time-series. There were subtle increases in the amount of hydrate exposed to the water between the end of the photographic time series and the recovery of the monitoring array. Mean temperatures (SDEV) and temperature range recorded by the probes were as follows: In-water: 7.87 ( 0.44) and 6.64-9.73 C In-hydrate: 7.81 ( 0.34) and 6.87-9.18 C In-sediment: 7.81 ( 0.16) and 7.79-9.18 C Spectra of the temperature records showed significant high-frequency peaks for in-water data corresponding to K1, M2 and M3 lunar tides. Of these peaks, only the K1 (23.9 h) was evident for in-hydrate records and none of the tidal peaks were evident for in-sediment records. All three records showed significant low-frequency periodicity at about 288 h. In-hydrate temperatures lagged the in-water temperatures by 6 h with high correlation. In-sediment temperatures lagged in-water temperatures by 288 h with weak correlation. These results constrain the response of shallow gas hydrate deposits to changing water temperature. MacDonald, I. R., N. L. Guinasso, Jr., et al. (1994). Gas hydrate that breaches the sea floor on the continental slope of the Gulf of Mexico. Geology 22: 699-702. Roberts, H., W. Wiseman Jr., et al. (1999). Surficial gas hydrates of the Louisiana continental slope--initial results of direct observations and in situ data collection. Offshore Technology Conference, Houston, TX, 10770: 259-272

MacDonald, I. R.; Vararo, M.; Bender, L.

2003-04-01

402

High-Temperature Seal for Sliding-Gate Valve  

Science.gov (United States)

Sliding-gate valve originally developed for rocket exhaust-gas ducts is sealed by a Belleville spring. It is simple, compact, and operates over a wider range of temperatures than conventional O-ring sealed valves.

Leonard, R. G.

1982-01-01

403

A study of silver behavior in gas-turbine high temperature gas-cooled reactor  

International Nuclear Information System (INIS)

In High Temperature Gas-cooled Reactors (HTGRs), some amounts of fission products (FPs) are released from fuel elements and are transported in the primary circuit with primary coolant during normal operation. Condensable FPs plateout on the inner surface of pipings and components in the primary circuit and the gamma-ray emitted from the plateout FPs becomes main source during maintenance works. In the design of a Gas-turbine High Temperature Gas-cooled Reactor (GT-HTGR), behaviour of FPs, especially of silver, is considered important from the view point of maintenance works of the gas-turbine. However, the behaviour of silver is not well known comparing with that of noble gases, iodine and cesium. Then a study of silver behaviour of the GT-HTGR was carried out based on experiences of High Temperature engineering Test Reactor (HTTR) design. The purposes of this study were (1) to determine how important the silver in the GT-HTGR; (2) to find out countermeasures to prevent silver release from fuel elements; and (3) to determine the items of future research and development which will be needed. In this study, evaluations of (1) inventory; (2) fractional release from fuel elements; (3) plateout distribution in the primary circuit; and (4) radiation dose at the gas-turbine were carried out. Based on this study, it was predicted that the gamma-ray from plateout silver contributes about a half of total radiation dose during maintenance work of the gas turbine. In future, it is expected that more detail data of silver release from fuel, plateout behaviour, etc. will be accumulated through the HTTR operation. (author). 12 refs, 7 figs, 5 tabs

404

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.)

405

New high temperature gas flow cell developed at ISIS  

Energy Technology Data Exchange (ETDEWEB)

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 O{sub 2}, Ar, CO{sub 2}, 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 log{sub 10}p(O{sub 2}) 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.

Haynes, R; Norberg, S T; Eriksson, S G; Chowdhury, M A H; Goodway, C M; Howells, G D; Kirichek, O; Hull, S, E-mail: oleg.kirichek@stfc.ac.uk

2010-11-01

406

New high temperature gas flow cell developed at ISIS  

Science.gov (United States)

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.

Haynes, R.; Norberg, S. T.; Eriksson, S. G.; Chowdhury, M. A. H.; Goodway, C. M.; Howells, G. D.; Kirichek, O.; Hull, S.

2010-11-01

407

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. Th