A 2003 heavy-duty diesel engine (2002 emissions level) was used to test a representative biodiesel fuel as well as the methyl esters of several different fatty acids. The fuel variables included degree of saturation, the oxygen content, and carbon chain length. In addition, two pure normal paraffins with the corresponding chain lengths of two of the methyl esters were also tested to determine the impact of chain length. The dependent variables were the NO x and the particulate emissions (PM). The results indicated that the primary fuel variable affecting the emissions is the oxygen content. The emissions results showed that the highest oxygen content test fuel had the lowest emissions of both NO x and PM. As compared to the baseline diesel fuel the NO x emissions were reduced by 5 percent and the PM emissions were reduced by 83 percent.
{"title":"Heavy-Duty Diesel Engine Emissions Tests Using Special Biodiesel Fuels","authors":"C. Sharp, T. W. Ryan, G. Knothe","doi":"10.4271/2005-01-3671","DOIUrl":"https://doi.org/10.4271/2005-01-3671","url":null,"abstract":"A 2003 heavy-duty diesel engine (2002 emissions level) was used to test a representative biodiesel fuel as well as the methyl esters of several different fatty acids. The fuel variables included degree of saturation, the oxygen content, and carbon chain length. In addition, two pure normal paraffins with the corresponding chain lengths of two of the methyl esters were also tested to determine the impact of chain length. The dependent variables were the NO x and the particulate emissions (PM). The results indicated that the primary fuel variable affecting the emissions is the oxygen content. The emissions results showed that the highest oxygen content test fuel had the lowest emissions of both NO x and PM. As compared to the baseline diesel fuel the NO x emissions were reduced by 5 percent and the PM emissions were reduced by 83 percent.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"36 1","pages":"1204-1212"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75108275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mikael Lemel, Anders Hultqvist, Andreas Vressner, Henrik Nordgren, H. Persson, B. Johansson
In this paper, the formaldehyde emissions from three different types of homogenous charge compression ignition (HCCI) engines are quantified for a range of fuels by means of Fourier Transform Infra Red (FTIR) spectroscopic analysis. The engines types are differentiated in the way the charge is prepared. The characterized engines are; the conventional port fuel injected one, a type that traps residuals by means of a Negative Valve Overlap (NVO) and finally a Direct Injected (DI) one. Fuels ranging from pure n-heptane to iso-octane via diesel, gasoline, PRF80, methanol and ethanol were characterized. Generally, the amount of formaldehyde found in the exhaust was decreasing with decreasing air/fuel ratio, advanced timing and increasing cycle temperature. It was found that increasing the source of formaldehyde i.e. the ratio of heat released in the cool-flame, brought on higher exhaust contents of formaldehyde. The application of a standard three-way catalyst completely removed formaldehyde from the exhaust stream.
{"title":"Quantification of the Formaldehyde Emissions from Different HCCI Engines Running on a Range of Fuels","authors":"Mikael Lemel, Anders Hultqvist, Andreas Vressner, Henrik Nordgren, H. Persson, B. Johansson","doi":"10.4271/2005-01-3724","DOIUrl":"https://doi.org/10.4271/2005-01-3724","url":null,"abstract":"In this paper, the formaldehyde emissions from three different types of homogenous charge compression ignition (HCCI) engines are quantified for a range of fuels by means of Fourier Transform Infra Red (FTIR) spectroscopic analysis. The engines types are differentiated in the way the charge is prepared. The characterized engines are; the conventional port fuel injected one, a type that traps residuals by means of a Negative Valve Overlap (NVO) and finally a Direct Injected (DI) one. Fuels ranging from pure n-heptane to iso-octane via diesel, gasoline, PRF80, methanol and ethanol were characterized. Generally, the amount of formaldehyde found in the exhaust was decreasing with decreasing air/fuel ratio, advanced timing and increasing cycle temperature. It was found that increasing the source of formaldehyde i.e. the ratio of heat released in the cool-flame, brought on higher exhaust contents of formaldehyde. The application of a standard three-way catalyst completely removed formaldehyde from the exhaust stream.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"54 1","pages":"1347-1357"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80427014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Driving cycle simulation of the heavy duty vehicle powertrain systems is presented as a methodological approach for evaluation of the engine operating points used for emission testing. This approach employs a backward facing method based on the quasi-steady approximation using the engine steady state characteristics. The driving cycle used in this study is extracted from the experimental data collected from the city buses in the real traffic conditions of the city of Tehran. The driving cycle is divided into several traffic conditions including congested, urban and extra-urban (highway). Several driving modes have also been considered including idle, cruise, deceleration and acceleration. The driving cycle simulation is then used to obtain the distribution of the engine operation for several driving cycles, traffic conditions and driving modes. Finally, the mapping from the driving cycle SAPM into the engine SLPM is employed to analyze the results. This study reveals that the common used 13-mode heavy duty engine test cycle is not necessarily compatible with the engine operating points for the city bus application, in particular at idle condition.
{"title":"Driving Cycle Simulation for Heady Duty Engine Emission Evaluation and Testing","authors":"M. Montazeri-Gh, Hirbod Varasteh, M. Naghizadeh","doi":"10.4271/2005-01-3796","DOIUrl":"https://doi.org/10.4271/2005-01-3796","url":null,"abstract":"Driving cycle simulation of the heavy duty vehicle powertrain systems is presented as a methodological approach for evaluation of the engine operating points used for emission testing. This approach employs a backward facing method based on the quasi-steady approximation using the engine steady state characteristics. The driving cycle used in this study is extracted from the experimental data collected from the city buses in the real traffic conditions of the city of Tehran. The driving cycle is divided into several traffic conditions including congested, urban and extra-urban (highway). Several driving modes have also been considered including idle, cruise, deceleration and acceleration. The driving cycle simulation is then used to obtain the distribution of the engine operation for several driving cycles, traffic conditions and driving modes. Finally, the mapping from the driving cycle SAPM into the engine SLPM is employed to analyze the results. This study reveals that the common used 13-mode heavy duty engine test cycle is not necessarily compatible with the engine operating points for the city bus application, in particular at idle condition.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"8 1","pages":"1506-1524"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82093268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Ahrenfeldt, T. K. Jensen, U. Henriksen, J. Schramm
About 2000 hours of gas engine operation with producer gas from biomass as fuel has been conducted on the gasification combined heat and power (CHP) demonstration and research plant, named "Viking" at the Technical University of Denmark. The plant and engine have been operated continuously and unmanned for five test periods of approximately 400 hours each. Two different control approaches have been applied and investigated: one where the flow rate of the producer gas is fixed and the engine operates with varying excess of air due to variation in gas composition and a second where the excess of air in the exhaust gas is fixed and the flow rate of produced gas from the gasifier is varying. It was seen that the optimal control approach regarding the gasifier operation resulted in engine operation with significant variation of the NO x emissions Producer gas properties and contaminations have been investigated. No detectable tar content was observed, and this was confirmed by three different measuring methods. Likewise, no particles were detected in the gas. Considerable amounts of ammonia were measured in the produced gas. An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging from 90% to 50% load. Relatively high emission of unburned CO was seen at all operating conditions when compared to the current regulation for CO emissions. Measurements of the emission of poly cyclic aromatic hydrocarbons (PAH) showed that there were no detectable PAH in exhaust gas from the engine when it is operated on producer gas. The emissions of aldehydes were measured to be significantly lower for producer gas operation than for natural gas. The engine heads have been removed several times in order to inspect the internal parts for formation of deposits, wear and corrosion, and no significant built up has been seen. Frequent oil analysis has been conducted and no significant degeneration has been seen.
{"title":"Investigation of Continuous Gas Engine CHP Operation on Biomass Producer Gas","authors":"J. Ahrenfeldt, T. K. Jensen, U. Henriksen, J. Schramm","doi":"10.4271/2005-01-3778","DOIUrl":"https://doi.org/10.4271/2005-01-3778","url":null,"abstract":"About 2000 hours of gas engine operation with producer gas from biomass as fuel has been conducted on the gasification combined heat and power (CHP) demonstration and research plant, named \"Viking\" at the Technical University of Denmark. The plant and engine have been operated continuously and unmanned for five test periods of approximately 400 hours each. Two different control approaches have been applied and investigated: one where the flow rate of the producer gas is fixed and the engine operates with varying excess of air due to variation in gas composition and a second where the excess of air in the exhaust gas is fixed and the flow rate of produced gas from the gasifier is varying. It was seen that the optimal control approach regarding the gasifier operation resulted in engine operation with significant variation of the NO x emissions Producer gas properties and contaminations have been investigated. No detectable tar content was observed, and this was confirmed by three different measuring methods. Likewise, no particles were detected in the gas. Considerable amounts of ammonia were measured in the produced gas. An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging from 90% to 50% load. Relatively high emission of unburned CO was seen at all operating conditions when compared to the current regulation for CO emissions. Measurements of the emission of poly cyclic aromatic hydrocarbons (PAH) showed that there were no detectable PAH in exhaust gas from the engine when it is operated on producer gas. The emissions of aldehydes were measured to be significantly lower for producer gas operation than for natural gas. The engine heads have been removed several times in order to inspect the internal parts for formation of deposits, wear and corrosion, and no significant built up has been seen. Frequent oil analysis has been conducted and no significant degeneration has been seen.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"34 1","pages":"1464-1475"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78665403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Hoshino, K. Kubo, Kazumoto Nakamura, M. Yamashita, Takeshi Hashimoto, K. Tomizawa, T. Ukai, S. Iwamoto, H. Yamamoto, Y. Naitoh, H. Yashima, K. Ueda, S. Nemoto, Tadaaki Ishikawa, Kouzo Yamada, T. Suzuki, T. Negishi, K. Kotaka, K. Takeoka, K. Takagi, M. Okubo, K. Yasuda, T. Kamitamari, K. Tawa
This paper reviews the development of the new four-stroke diesel engine oil standards, JASO DH-2 and DL-1 (JASO M335-05) for Japanese automotive diesel engines equipped with after treatment devices, e.g. Diesel Particulate Filter (DPF) to meet the new long-term emissions regulations. These standards have been introduced in Japan in April 2005. The standards prescribe the minimum performance for engine oils conforming to Japan-made four-stroke diesel engines with aftertreatment devices using low sulfur diesel fuel (less than or equal to 0.005 mass % sulfur). The engine test requirements for these new standards are basically the same as those of the JASO DH-1 automotive diesel engine oil standard (JASO M-355 2000) to meet engine oil performances with soot dispersancy (ASTM D 5967-99), piston detergency (JASO M336-98), thermal and oxidation stability (ASTM Seq. IIIE and IIIF), and anti-wear performance (JASO M354-99). The specified bench tests measure hot surface deposit control, anti-foaming, volatility, anticorrosion, shear-stability, base number, and seal compatibility. Limits for chemical elements and sulfated ash are newly set to protect aftertreatment devices.
本文综述了为满足新的长期排放法规，日本汽车柴油发动机配备了后处理装置，如柴油微粒过滤器(DPF)， JASO DH-2和DL-1 (JASO M335-05)的新四冲程柴油发动机机油标准的发展情况。这些标准已于2005年4月在日本引入。该标准规定了符合日本制造的四冲程柴油发动机的最低性能，后处理装置使用低硫柴油燃料(低于或等于0.005质量%硫)。这些新标准的发动机试验要求与JASO DH-1车用柴油发动机机油标准(JASO m - 3552000)基本相同，以满足油烟分散性(ASTM D 5967-99)、活塞清净性(JASO M336-98)、热稳定性和氧化稳定性(ASTM Seq)等发动机机油性能。IIIE和IIIF)，以及抗磨性能(JASO M354-99)。指定的台架试验测量热表面沉积控制，抗泡沫，挥发性，防腐，剪切稳定性，基数和密封兼容性。为了保护后处理装置，新设定了化学元素和硫酸盐灰分的限值。
{"title":"New Four-stroke Diesel Engine Oil Standards for Japanese Market: JASO DH-2 and DL-1","authors":"T. Hoshino, K. Kubo, Kazumoto Nakamura, M. Yamashita, Takeshi Hashimoto, K. Tomizawa, T. Ukai, S. Iwamoto, H. Yamamoto, Y. Naitoh, H. Yashima, K. Ueda, S. Nemoto, Tadaaki Ishikawa, Kouzo Yamada, T. Suzuki, T. Negishi, K. Kotaka, K. Takeoka, K. Takagi, M. Okubo, K. Yasuda, T. Kamitamari, K. Tawa","doi":"10.4271/2005-01-3718","DOIUrl":"https://doi.org/10.4271/2005-01-3718","url":null,"abstract":"This paper reviews the development of the new four-stroke diesel engine oil standards, JASO DH-2 and DL-1 (JASO M335-05) for Japanese automotive diesel engines equipped with after treatment devices, e.g. Diesel Particulate Filter (DPF) to meet the new long-term emissions regulations. These standards have been introduced in Japan in April 2005. The standards prescribe the minimum performance for engine oils conforming to Japan-made four-stroke diesel engines with aftertreatment devices using low sulfur diesel fuel (less than or equal to 0.005 mass % sulfur). The engine test requirements for these new standards are basically the same as those of the JASO DH-1 automotive diesel engine oil standard (JASO M-355 2000) to meet engine oil performances with soot dispersancy (ASTM D 5967-99), piston detergency (JASO M336-98), thermal and oxidation stability (ASTM Seq. IIIE and IIIF), and anti-wear performance (JASO M354-99). The specified bench tests measure hot surface deposit control, anti-foaming, volatility, anticorrosion, shear-stability, base number, and seal compatibility. Limits for chemical elements and sulfated ash are newly set to protect aftertreatment devices.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"32 1","pages":"1323-1333"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90368013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new electronic sensor has been developed to measure the time-resolved concentration of carbonaceous particulate matter (PM) emitted in engine exhaust. The sensor is approximately the size of a standard automotive spark-plug or lambda sensor and can be mounted directly in the engine exhaust. It consists of a pair of closely spaced electrically isolated electrodes that protrude into the exhaust flow. One electrode is given a voltage bias of 1000 V while the other is the signal electrode. The sensor is capable of providing cycle-resolved feedback on the carbonaceous PM concentration in the exhaust to the engine control unit (ECU), thereby enabling real-time control of engine operating parameters to lower PM emissions. This paper reports the results of an experimental study of various parameters that affect the performance of the electronic sensor. Parameters considered included sensor electrode length, diameter, electrode spacing, applied bias voltage, bulk flow velocity across the sensor electrodes, and the concentration of carbonaceous particulate matter in engine exhaust. The sensor was tested in the exhaust of a single cylinder diesel engine. The sensor signal varied linearly with the carbon mass concentration in the exhaust, the applied bias voltage and electrode length; it also showed some sensitivity to the bulk flow velocity, and an inverse power dependence on the spacing between the electrodes. Electrode diameter did not have a significant effect on the sensor signal. A correlation was developed to predict the sensor signal under any engine operating condition and values of these parameters. This correlation could be used to develop control strategies for the sensor for on-board operation in a production vehicle. The experiments also provided insight into the physical mechanism governing sensor behavior, regarding the charge transport between the two electrodes of the sensor.
{"title":"Performance Characteristics of a New On-Board Engine Exhaust Particulate Matter Sensor","authors":"A. Warey, M. Hall","doi":"10.4271/2005-01-3792","DOIUrl":"https://doi.org/10.4271/2005-01-3792","url":null,"abstract":"A new electronic sensor has been developed to measure the time-resolved concentration of carbonaceous particulate matter (PM) emitted in engine exhaust. The sensor is approximately the size of a standard automotive spark-plug or lambda sensor and can be mounted directly in the engine exhaust. It consists of a pair of closely spaced electrically isolated electrodes that protrude into the exhaust flow. One electrode is given a voltage bias of 1000 V while the other is the signal electrode. The sensor is capable of providing cycle-resolved feedback on the carbonaceous PM concentration in the exhaust to the engine control unit (ECU), thereby enabling real-time control of engine operating parameters to lower PM emissions. This paper reports the results of an experimental study of various parameters that affect the performance of the electronic sensor. Parameters considered included sensor electrode length, diameter, electrode spacing, applied bias voltage, bulk flow velocity across the sensor electrodes, and the concentration of carbonaceous particulate matter in engine exhaust. The sensor was tested in the exhaust of a single cylinder diesel engine. The sensor signal varied linearly with the carbon mass concentration in the exhaust, the applied bias voltage and electrode length; it also showed some sensitivity to the bulk flow velocity, and an inverse power dependence on the spacing between the electrodes. Electrode diameter did not have a significant effect on the sensor signal. A correlation was developed to predict the sensor signal under any engine operating condition and values of these parameters. This correlation could be used to develop control strategies for the sensor for on-board operation in a production vehicle. The experiments also provided insight into the physical mechanism governing sensor behavior, regarding the charge transport between the two electrodes of the sensor.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"337 1","pages":"1489-1497"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90458849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Parks, S. Huff, J. Pihl, Jae-Soon Choi, B. West
NOx emissions have traditionally been difficult to control from diesel engines; however, lean NOx trap catalysts have been shown to reduce NOx emissions from diesel engines by greater than 90% under some conditions. It is imperative that lean NOx traps be highly selective to N 2 to achieve the designed NOx emissions reduction. If selectivity for NOx reduction to NH 3 or N 2 O is significant then, ultimately, higher levels of pollution or greenhouse emissions will result. Here studies of the N 2 selectivity of lean NOx trap regeneration with in-cylinder techniques are presented. Engine dynamometer studies with a light-duty engine were performed, and a lean NOx trap in the exhaust system was regenerated by controlling in-cylinder fuel injection timing and amounts to achieve rich exhaust conditions. NH 3 and N 2 O emissions were analyzed with FTIR spectroscopy. Both engine and bench experiments show that excess reductant delivery during regeneration leads to high NH 3 emissions and poor N 2 selectivity. Specific design of in-cylinder regeneration techniques that minimize excess reductant or allow O 2 purge can optimize N 2 selectivity of the lean NOx trap catalyst.
{"title":"Nitrogen Selectivity in Lean NOx Trap Catalysis with Diesel Engine In-Cylinder Regeneration","authors":"J. Parks, S. Huff, J. Pihl, Jae-Soon Choi, B. West","doi":"10.4271/2005-01-3876","DOIUrl":"https://doi.org/10.4271/2005-01-3876","url":null,"abstract":"NOx emissions have traditionally been difficult to control from diesel engines; however, lean NOx trap catalysts have been shown to reduce NOx emissions from diesel engines by greater than 90% under some conditions. It is imperative that lean NOx traps be highly selective to N 2 to achieve the designed NOx emissions reduction. If selectivity for NOx reduction to NH 3 or N 2 O is significant then, ultimately, higher levels of pollution or greenhouse emissions will result. Here studies of the N 2 selectivity of lean NOx trap regeneration with in-cylinder techniques are presented. Engine dynamometer studies with a light-duty engine were performed, and a lean NOx trap in the exhaust system was regenerated by controlling in-cylinder fuel injection timing and amounts to achieve rich exhaust conditions. NH 3 and N 2 O emissions were analyzed with FTIR spectroscopy. Both engine and bench experiments show that excess reductant delivery during regeneration leads to high NH 3 emissions and poor N 2 selectivity. Specific design of in-cylinder regeneration techniques that minimize excess reductant or allow O 2 purge can optimize N 2 selectivity of the lean NOx trap catalyst.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"2014 1","pages":"1753-1765"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86617366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reaction zone of a diesel fuel jet stabilizes at a location downstream of the fuel injector once the initial autoignition phase is over. This distance is referred to as flame lift-off length. Recent investigations have examined the effects of a wide range of parameters (injection pressure, orifice diameter, and ambient gas temperature, density and oxygen concentration) on lift-off length under quiescent diesel conditions. Many of the experimental trends in lift-off length were in agreement with scaling laws developed for turbulent, premixed flame propagation in gas-jet lifted flames at atmospheric conditions. However, several effects did not correlate with the gas-jet scaling laws, suggesting that other mechanisms could be important to lift-off stabilization at diesel conditions. This paper shows experimental evidence that ignition processes affect diesel lift-off stabilization. Experiments were performed in the same optically-accessible combustion vessel as the previous lift-off research. The experimental results show that the ignition quality of a fuel affects lift-off. Fuels with shorter ignition delays generally produce shorter lift-off lengths. In addition, a cool flame is found upstream of, or near the same axial location as, the quasi-steady lift-off length, indicating that first-stage ignition processes affect lift-off. High-speed chemiluminescence imaging also shows that high-temperature self-ignition occasionallymore » occurs in kernels that are upstream of, and detached from, the high-temperature reaction zone downstream, suggesting that the lift-off stabilization is not by flame propagation into upstream reactants in this instance. Finally, analysis of the previous lift-off length database shows that the time-scale for jet mixing from injector-tip orifice to lift-off length collapses to an Arrhenius-type expression, a common method for describing ignition delay in diesel sprays. This Arrhenius-based lift-off length correlation shows comparable accuracy as a previous power-law fit of the No.2 diesel lift-off length database.« less
{"title":"Relationship Between Ignition Processes and the Lift-Off Length of Diesel Fuel Jets","authors":"L. Pickett, D. Siebers, C. Idicheria","doi":"10.4271/2005-01-3843","DOIUrl":"https://doi.org/10.4271/2005-01-3843","url":null,"abstract":"The reaction zone of a diesel fuel jet stabilizes at a location downstream of the fuel injector once the initial autoignition phase is over. This distance is referred to as flame lift-off length. Recent investigations have examined the effects of a wide range of parameters (injection pressure, orifice diameter, and ambient gas temperature, density and oxygen concentration) on lift-off length under quiescent diesel conditions. Many of the experimental trends in lift-off length were in agreement with scaling laws developed for turbulent, premixed flame propagation in gas-jet lifted flames at atmospheric conditions. However, several effects did not correlate with the gas-jet scaling laws, suggesting that other mechanisms could be important to lift-off stabilization at diesel conditions. This paper shows experimental evidence that ignition processes affect diesel lift-off stabilization. Experiments were performed in the same optically-accessible combustion vessel as the previous lift-off research. The experimental results show that the ignition quality of a fuel affects lift-off. Fuels with shorter ignition delays generally produce shorter lift-off lengths. In addition, a cool flame is found upstream of, or near the same axial location as, the quasi-steady lift-off length, indicating that first-stage ignition processes affect lift-off. High-speed chemiluminescence imaging also shows that high-temperature self-ignition occasionallymore » occurs in kernels that are upstream of, and detached from, the high-temperature reaction zone downstream, suggesting that the lift-off stabilization is not by flame propagation into upstream reactants in this instance. Finally, analysis of the previous lift-off length database shows that the time-scale for jet mixing from injector-tip orifice to lift-off length collapses to an Arrhenius-type expression, a common method for describing ignition delay in diesel sprays. This Arrhenius-based lift-off length correlation shows comparable accuracy as a previous power-law fit of the No.2 diesel lift-off length database.« less","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"1 1","pages":"1714-1731"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84863605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Cantore, S. Fontanesi, V. Gagliardi, Simone Malaguti
The paper aims at providing information about the in-cylinder flow structure and its evolution of a high speed direct injection (HSD1) four valve per cylinder engine for off-highway applications. Fully transient CFD analyses by means of state-of-the-art tools and methodologies are carried out for the whole intake and compression strokes, in order to evaluate port effects on both engine permability and in-cylinder flow field evolution. Organized mean motions (i.e., swirl, tumble and squish) are investigated, trying to establish general rules in the port design optimization process, addressing relationships between the relative port orientation and the in-cylinder flow structure. Different port configurations are compared, each deriving from the rotation of the BASE port configuration on two different planes, the former being perpendicular to the cylinder axis, while the latter being parallel to the cylinder axis. Relative intake port orientation proves to strongly influence the flow field evolution within the combustion chamber, and is therefore expected to play a non negligible role on the subsequent spray evolution and fuel combustion.
{"title":"Effects of relative port orientation on the in-cylinder flow patterns in a small unit displacement HSDI Diesel Engine","authors":"G. Cantore, S. Fontanesi, V. Gagliardi, Simone Malaguti","doi":"10.4271/2005-32-0093","DOIUrl":"https://doi.org/10.4271/2005-32-0093","url":null,"abstract":"The paper aims at providing information about the in-cylinder flow structure and its evolution of a high speed direct injection (HSD1) four valve per cylinder engine for off-highway applications. Fully transient CFD analyses by means of state-of-the-art tools and methodologies are carried out for the whole intake and compression strokes, in order to evaluate port effects on both engine permability and in-cylinder flow field evolution. Organized mean motions (i.e., swirl, tumble and squish) are investigated, trying to establish general rules in the port design optimization process, addressing relationships between the relative port orientation and the in-cylinder flow structure. Different port configurations are compared, each deriving from the rotation of the BASE port configuration on two different planes, the former being perpendicular to the cylinder axis, while the latter being parallel to the cylinder axis. Relative intake port orientation proves to strongly influence the flow field evolution within the combustion chamber, and is therefore expected to play a non negligible role on the subsequent spray evolution and fuel combustion.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"28 1","pages":"1770-1781"},"PeriodicalIF":0.0,"publicationDate":"2005-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84257541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Due to emission regulations for hand-held power tools more and more stratified-charge two-stroke engines enter into the market [Sawada et al. 1998, Zahn et al. 2000]. These engines require investigations and treatment for tuning the transient behaviour that are beyond the methods of the tuning for conventional engines. Especially the in-cylinder air-to-fuel-ratio cannot be determined from simple exhaust gas analysis any more. This paper presents an exhaust gas sampling system to enable the use of a standard lambda meter for a fast response measurement of air to fuel ratio out of the combustion chamber. The gas is sampled by means of a small restriction directly out of the combustion chamber. In case of miss-fire the hydrocarbon concentration in the sample is too high for the lambda sensor. With a dilution or a pre-converter system the hydrocarbon concentration can be adjusted to the range of the lambda sensor. Verification has been done with several tests. The air to fuel ratio in combustion is a key issue to tune the transient behaviour and to meet all customer requirements of the engine performance.
由于手持式电动工具的排放法规，越来越多的分层充能二冲程发动机进入市场[Sawada et al. 1998, Zahn et al. 2000]。这些发动机需要调查和处理，以调整瞬态行为，这超出了传统发动机的调整方法。特别是气缸内的空燃比已不能通过简单的尾气分析来确定。本文提出了一个废气采样系统，使使用一个标准的lambda仪表的快速响应测量空气燃料比走出燃烧室。气体通过一个小的限制装置直接从燃烧室中取样。在漏火的情况下，样品中的碳氢化合物浓度对于lambda传感器来说太高了。通过稀释或预转化器系统，碳氢化合物浓度可以调整到lambda传感器的范围内。已经通过几次测试进行了验证。空气燃料燃烧比是调节发动机瞬态性能和满足客户对发动机性能要求的关键问题。
{"title":"Fast Response Measurement of Combustion Air to Fuel Ratio for Stratified Two-Stroke Engines","authors":"Klaus Geyer, C. Hallé, H. Roskamp","doi":"10.4271/2005-32-0109","DOIUrl":"https://doi.org/10.4271/2005-32-0109","url":null,"abstract":"Due to emission regulations for hand-held power tools more and more stratified-charge two-stroke engines enter into the market [Sawada et al. 1998, Zahn et al. 2000]. These engines require investigations and treatment for tuning the transient behaviour that are beyond the methods of the tuning for conventional engines. Especially the in-cylinder air-to-fuel-ratio cannot be determined from simple exhaust gas analysis any more. This paper presents an exhaust gas sampling system to enable the use of a standard lambda meter for a fast response measurement of air to fuel ratio out of the combustion chamber. The gas is sampled by means of a small restriction directly out of the combustion chamber. In case of miss-fire the hydrocarbon concentration in the sample is too high for the lambda sensor. With a dilution or a pre-converter system the hydrocarbon concentration can be adjusted to the range of the lambda sensor. Verification has been done with several tests. The air to fuel ratio in combustion is a key issue to tune the transient behaviour and to meet all customer requirements of the engine performance.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"26 1","pages":"1782-1787"},"PeriodicalIF":0.0,"publicationDate":"2005-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89885001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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