The present work was performed as part of Project MAAT | Multibody Advanced Airship for Transport | with ref. 285602, supported by European Union through the 7th Framework Programme
{"title":"Increasing aeronautic electric propulsion performances by cogeneration and heat recovery","authors":"M. Trancossi, A. Dumas, P. Stewart, D. Vucinic","doi":"10.4271/2014-01-2106","DOIUrl":"https://doi.org/10.4271/2014-01-2106","url":null,"abstract":"The present work was performed as part of Project MAAT | Multibody Advanced Airship for Transport | with ref. 285602, supported by European Union through the 7th Framework Programme","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86377791","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 interaction between a combusting diesel spray and a wall was studied by measuring the spray flame temperature time and spatially resolved. The influence of injection sequences, injection pressure and gas conditions on the heat transfer between the combusting spray and the wall was investigated by measuring the flame temperature during the complete injection event. The flame temperature was measured by an emission based optical method and determined by comparing the relative emission intensities from the soot in the flame at two wavelength intervals. The measurements were done by employing a monochromatic and non intensified high speed camera, an array of mirrors, interference filters and a beam splitter. The studies were carried out in the Chalmers High Pressure High Temperature (HP/HT) spray rig at conditions similar to those prevailing in a direct injected diesel engine prior to the injection of fuel. Fuel was injected into the combustion chamber by a common rail system using an injector with a single hole nozzle. The combusting spray impinged on a wall whose temperature was similar to the combustion chamber gas temperature. Results of these experiments show variations in the flame temperature as a consequence of the interaction between the combusting spray and the wall. There is a reduction in the flame temperature after impingement followed by a temperature rise as the wall is heated up by the flame. The effects caused by injection pressure, injection sequences and gas temperature lead to differences
{"title":"Time and spatially resolved temperature measurements of a combusting diesel spray impinging on a wall","authors":"R. Ochoterena, S. Andersson","doi":"10.4271/2008-01-1608","DOIUrl":"https://doi.org/10.4271/2008-01-1608","url":null,"abstract":"The interaction between a combusting diesel spray and a wall \u0000was studied by measuring the spray flame temperature time \u0000and spatially resolved. The influence of injection sequences, \u0000injection pressure and gas conditions on the heat transfer between \u0000the combusting spray and the wall was investigated by \u0000measuring the flame temperature during the complete injection \u0000event. \u0000The flame temperature was measured by an emission based optical \u0000method and determined by comparing the relative emission \u0000intensities from the soot in the flame at two wavelength intervals. \u0000The measurements were done by employing a monochromatic \u0000and non intensified high speed camera, an array of mirrors, interference \u0000filters and a beam splitter. The studies were carried \u0000out in the Chalmers High Pressure High Temperature (HP/HT) \u0000spray rig at conditions similar to those prevailing in a direct injected \u0000diesel engine prior to the injection of fuel. Fuel was injected \u0000into the combustion chamber by a common rail system \u0000using an injector with a single hole nozzle. The combusting \u0000spray impinged on a wall whose temperature was similar to the \u0000combustion chamber gas temperature. \u0000Results of these experiments show variations in the flame temperature \u0000as a consequence of the interaction between the combusting \u0000spray and the wall. There is a reduction in the flame \u0000temperature after impingement followed by a temperature rise \u0000as the wall is heated up by the flame. The effects caused by injection \u0000pressure, injection sequences and gas temperature lead \u0000to differences","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2008-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91251361","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}
K. Chakravarthy, J. Mcfarlane, Stuart Daw, Y. Ra, R. Reitz, Jelani Griffin
In this study we identify components of a typical biodiesel fuel and estimate both their individual and mixed thermo-physical and transport properties. We then use the estimated mixture properties in computational simulations to gauge the extent to which combustion is modified when biodiesel is substituted for conventional diesel fuel. Our simulation studies included both regular diesel combustion (DI) and premixed charge compression ignition (PCCI). Preliminary results indicate that biodiesel ignition is significantly delayed due to slower liquid evaporation, with the effects being more pronounced for DI than PCCI. The lower vapor pressure and higher liquid heat capacity of biodiesel are two key contributors to this slower rate of evaporation. Other physical properties are more similar between the two fuels, and their impacts are not clearly evident in the present study. Future studies of diesel combustion sensitivity to both physical and chemical properties of biodiesel are suggested.
{"title":"Physical Properties of Bio-Diesel and Implications for Use of Bio-Diesel in Diesel Engines","authors":"K. Chakravarthy, J. Mcfarlane, Stuart Daw, Y. Ra, R. Reitz, Jelani Griffin","doi":"10.4271/2007-01-4030","DOIUrl":"https://doi.org/10.4271/2007-01-4030","url":null,"abstract":"In this study we identify components of a typical biodiesel fuel and estimate both their individual and mixed thermo-physical and transport properties. We then use the estimated mixture properties in computational simulations to gauge the extent to which combustion is modified when biodiesel is substituted for conventional diesel fuel. Our simulation studies included both regular diesel combustion (DI) and premixed charge compression ignition (PCCI). Preliminary results indicate that biodiesel ignition is significantly delayed due to slower liquid evaporation, with the effects being more pronounced for DI than PCCI. The lower vapor pressure and higher liquid heat capacity of biodiesel are two key contributors to this slower rate of evaporation. Other physical properties are more similar between the two fuels, and their impacts are not clearly evident in the present study. Future studies of diesel combustion sensitivity to both physical and chemical properties of biodiesel are suggested.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2007-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79013445","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}
5,032 people aged 70 or older were killed on US roads in 2005. Of these, 827 were drivers killed in single-vehicle crashes. The remaining 4,205 were all killed in crashes involving at least one other driver. While a vast body of literature has focused on older drivers, this paper addresses the other drivers involved in the crashes that account for 84% of the deaths of road users 70 and over. The other drivers can be placed into three categories: 1) Drivers of vehicles involved in crashes in which pedestrians aged 70 or older are killed; 2) Drivers involved in two-vehicle crashes in which drivers aged 70 or older are killed and 3) Drivers of vehicles in which passengers aged 70 or older are killed, and drivers of vehicles involved in crashes with vehicles transporting such passengers. Analysis using data for 2000-2005 finds that 89% of pedestrian fatalities aged 70 or older occurred in crashes in which the driver was aged 69 or younger. For all categories combined it is found that 77% of the crashes that annually kill more than 5,000 road users aged 70 or older involve a driver 69 or younger. Countermeasures that target older road users specifically have limited potential. Reducing crash risk for drivers who are not old has far greater potential to reduce casualties to the elderly. To do so requires the US to adopt effective traffic safety policies and abandon its present focus on methods that have been shown repeatedly to not work. Effective policies are available, proven, and already saving large numbers of lives of road users of all ages outside the US. Language: en
{"title":"Drivers Involved in Crashes Killing Older Road Users","authors":"L. Evans","doi":"10.4271/2007-01-1165","DOIUrl":"https://doi.org/10.4271/2007-01-1165","url":null,"abstract":"5,032 people aged 70 or older were killed on US roads in 2005. Of these, 827 were drivers killed in single-vehicle crashes. The remaining 4,205 were all killed in crashes involving at least one other driver. While a vast body of literature has focused on older drivers, this paper addresses the other drivers involved in the crashes that account for 84% of the deaths of road users 70 and over. The other drivers can be placed into three categories: 1) Drivers of vehicles involved in crashes in which pedestrians aged 70 or older are killed; 2) Drivers involved in two-vehicle crashes in which drivers aged 70 or older are killed and 3) Drivers of vehicles in which passengers aged 70 or older are killed, and drivers of vehicles involved in crashes with vehicles transporting such passengers. Analysis using data for 2000-2005 finds that 89% of pedestrian fatalities aged 70 or older occurred in crashes in which the driver was aged 69 or younger. For all categories combined it is found that 77% of the crashes that annually kill more than 5,000 road users aged 70 or older involve a driver 69 or younger. Countermeasures that target older road users specifically have limited potential. Reducing crash risk for drivers who are not old has far greater potential to reduce casualties to the elderly. To do so requires the US to adopt effective traffic safety policies and abandon its present focus on methods that have been shown repeatedly to not work. Effective policies are available, proven, and already saving large numbers of lives of road users of all ages outside the US. Language: en","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"313 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2007-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79696505","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. Spice, J. Speer, G. Krauss, D. Matlock, H. Meyer
The potential to reduce the susceptibility to quench embrittlement, a fracture mechanism that promotes intergranular fracture in high carbon steels, and to improve the bending fatigue performance of vacuum carburized modified SAE 4320 steels was evaluated. Data were obtained on an industrially produced SAE 4320 steel and four laboratory produced steels based on the 4320 composition but with additions of Si (1.0 or 2.0 wt pct) and B (0 or 17 ppm). All five alloys were vacuum carburized together and gas quenched with three different cooling rates as controlled by the gas quench conditions: 10 bar nitrogen, and 15 and 20 bar helium. Modified Brugger fatigue samples of each alloy and quench condition were tested in cantilever bending and failed samples were analyzed with scanning electron and Auger spectroscopy. Standard S-N curves and endurance limits were obtained and the fracture surfaces were evaluated using both light and electron microscopy techniques to determine fracture initiation sites and fracture growth mechanisms, both in the stable fatigue crack growth zone and in the overload zone. The percentage of transgranular fracture in the carburized case was quantified and used as a measure of the susceptibility to quench embrittlement. The susceptibility to quench embrittlement was more » observed to be independent of quench rate and boron additions, but depended on Si content. With an increase in Si content, the extent of intergranular fracture decreased, indicating a decrease in the susceptibility to quench embrittlement. However, with an increase in Si content to 2 wt pct, significant grain growth occurred producing prior austenite grain sizes 2 to 3 times those observed in the base or 1 pct Si alloys. The grain growth experienced by the high Si alloys was interpreted to result from the effects the retardation of cementite nucleation and growth at austenite grain boundaries. The fatigue properties were shown to be essentially independent of cooling rate and differences in fatigue performance were assessed primarily based on a consideration of alloy additions. Fatigue crack nucleation in all samples exhibited similar characteristics, i.e. intergranular crack nucleation at a small cluster of surface grains. The larger grain sizes in the 2 wt pct Si alloys were shown to be the primary factor that affected endurance limits. The 2 wt pct Si alloys exhibited endurance limits of approximately 915 MPa while the baseline 4320 alloy and the modified 1 wt pct Si alloys exhibited higher endurance limits of approximately 1070 MPa. In comparison to fatigue data on gas carburized samples reported in the literature the samples in this study exhibited more variability in measured lifetimes with many samples exhibiting runout at stress levels significantly greater than the measured endurance limits. Implications of this study with respect to the development of potential new carburizing alloys are discussed. « less
{"title":"Effects of Silicon and Boron Additions on the Susceptibility to Quench Embrittlement and the Bending Fatigue Performance of Vacuum Carburized Modified 4320 Steel","authors":"J. Spice, J. Speer, G. Krauss, D. Matlock, H. Meyer","doi":"10.4271/2007-01-1005","DOIUrl":"https://doi.org/10.4271/2007-01-1005","url":null,"abstract":"The potential to reduce the susceptibility to quench embrittlement, a fracture mechanism that promotes intergranular fracture in high carbon steels, and to improve the bending fatigue performance of vacuum carburized modified SAE 4320 steels was evaluated. Data were obtained on an industrially produced SAE 4320 steel and four laboratory produced steels based on the 4320 composition but with additions of Si (1.0 or 2.0 wt pct) and B (0 or 17 ppm). All five alloys were vacuum carburized together and gas quenched with three different cooling rates as controlled by the gas quench conditions: 10 bar nitrogen, and 15 and 20 bar helium. Modified Brugger fatigue samples of each alloy and quench condition were tested in cantilever bending and failed samples were analyzed with scanning electron and Auger spectroscopy. Standard S-N curves and endurance limits were obtained and the fracture surfaces were evaluated using both light and electron microscopy techniques to determine fracture initiation sites and fracture growth mechanisms, both in the stable fatigue crack growth zone and in the overload zone. The percentage of transgranular fracture in the carburized case was quantified and used as a measure of the susceptibility to quench embrittlement. The susceptibility to quench embrittlement was more » observed to be independent of quench rate and boron additions, but depended on Si content. With an increase in Si content, the extent of intergranular fracture decreased, indicating a decrease in the susceptibility to quench embrittlement. However, with an increase in Si content to 2 wt pct, significant grain growth occurred producing prior austenite grain sizes 2 to 3 times those observed in the base or 1 pct Si alloys. The grain growth experienced by the high Si alloys was interpreted to result from the effects the retardation of cementite nucleation and growth at austenite grain boundaries. The fatigue properties were shown to be essentially independent of cooling rate and differences in fatigue performance were assessed primarily based on a consideration of alloy additions. Fatigue crack nucleation in all samples exhibited similar characteristics, i.e. intergranular crack nucleation at a small cluster of surface grains. The larger grain sizes in the 2 wt pct Si alloys were shown to be the primary factor that affected endurance limits. The 2 wt pct Si alloys exhibited endurance limits of approximately 915 MPa while the baseline 4320 alloy and the modified 1 wt pct Si alloys exhibited higher endurance limits of approximately 1070 MPa. In comparison to fatigue data on gas carburized samples reported in the literature the samples in this study exhibited more variability in measured lifetimes with many samples exhibiting runout at stress levels significantly greater than the measured endurance limits. Implications of this study with respect to the development of potential new carburizing alloys are discussed. « less","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2007-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84878034","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. Koltsakis, O. Haralampous, Z. Samaras, L. Kraemer, F. Heimlich, Kai Behnk
{"title":"Control Strategies for Peak Temperature Limitation in DPF Regeneration Supported by Validated Modeling","authors":"G. Koltsakis, O. Haralampous, Z. Samaras, L. Kraemer, F. Heimlich, Kai Behnk","doi":"10.4271/2007-01-1127","DOIUrl":"https://doi.org/10.4271/2007-01-1127","url":null,"abstract":"","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2007-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78696070","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}
N. Cavina, D. Moro, L. Poggio, D. Zecchetti, R. Nanni, A. Gelmetti
{"title":"Individual Cylinder Combustion Control Based on Real-Time Processing of Ion Current Signals","authors":"N. Cavina, D. Moro, L. Poggio, D. Zecchetti, R. Nanni, A. Gelmetti","doi":"10.4271/2007-01-1510","DOIUrl":"https://doi.org/10.4271/2007-01-1510","url":null,"abstract":"","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"18 1","pages":"1025-1034"},"PeriodicalIF":0.0,"publicationDate":"2007-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82628958","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}
S. Kook, C. Bae, P. Miles, Dae Choi, M. Bergin, R. Reitz
Support for this research was provided by the U.S. Department of Energy, Office of FreedomCAR and Vehicle Technologies. The research was performed at the Combustion Research Facility, Sandia National Laboratories, Livermore, California. Sandia is a multiprogram laboratory operated by Sandia Corporation,a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000. The BK21 and Future Vehicle Technology Development Corps. of Korea supported Sanghoon Kook's visiting research. The authors express their appreciation to Mark Musculus and Lyle Pickett for providing the high speed camera and the Matlab source code to calculate the adiabatic flame temperature.
{"title":"The effect of swirl ratio and fuel injection parameters on CO emission and fuel conversion efficiency for high-dilution, low-temperature combustion in an automotive diesel engine.","authors":"S. Kook, C. Bae, P. Miles, Dae Choi, M. Bergin, R. Reitz","doi":"10.4271/2006-01-0197","DOIUrl":"https://doi.org/10.4271/2006-01-0197","url":null,"abstract":"Support for this research was provided by the U.S. Department of Energy, Office of FreedomCAR and Vehicle Technologies. The research was performed at the Combustion Research Facility, Sandia National Laboratories, Livermore, California. Sandia is a multiprogram laboratory operated by Sandia Corporation,a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000. The BK21 and Future Vehicle Technology Development Corps. of Korea supported Sanghoon Kook's visiting research. The authors express their appreciation to Mark Musculus and Lyle Pickett for providing the high speed camera and the Matlab source code to calculate the adiabatic flame temperature.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"1 1","pages":"1370-1381"},"PeriodicalIF":0.0,"publicationDate":"2006-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75487167","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}
Carbon based friction materials continue to gain increasing acceptance in many friction applications. One unique class of carbon based friction materials is Chemical Vapor Deposited carbon fabric (CVD Fabric™) Since 1991, CVD Fabric™ has been used in production automotive wet friction applications including limited slip differentials and heavy and medium duty truck transmission synchronizers. It offers stable friction levels, low wear rates and is readily wetted by transmission oils. Because CVD Fabric does not soften with temperature and is unaffected by solvents, this high energy absorption, high abuse tolerant material may provide significant performance advantages in off-highway wet brake and clutch applications. This paper will explore the Physical, mechanical and tribological properties of CVD Fabric wet friction materials.
{"title":"Pyrolytic Carbon Wet Friction Materials","authors":"S. Awasthi, G. Taccini","doi":"10.4271/2005-01-3588","DOIUrl":"https://doi.org/10.4271/2005-01-3588","url":null,"abstract":"Carbon based friction materials continue to gain increasing acceptance in many friction applications. One unique class of carbon based friction materials is Chemical Vapor Deposited carbon fabric (CVD Fabric™) Since 1991, CVD Fabric™ has been used in production automotive wet friction applications including limited slip differentials and heavy and medium duty truck transmission synchronizers. It offers stable friction levels, low wear rates and is readily wetted by transmission oils. Because CVD Fabric does not soften with temperature and is unaffected by solvents, this high energy absorption, high abuse tolerant material may provide significant performance advantages in off-highway wet brake and clutch applications. This paper will explore the Physical, mechanical and tribological properties of CVD Fabric wet friction materials.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"3 1","pages":"260-263"},"PeriodicalIF":0.0,"publicationDate":"2005-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84158722","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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