The Experts below are selected from a list of 11004 Experts worldwide ranked by ideXlab platform
C Astorga - One of the best experts on this subject based on the ideXlab platform.
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intercomparison of real time tailpipe ammonia measurements from vehicles Tested over the new world harmonized light duty vehicle Test Cycle wltc
Environmental Science and Pollution Research, 2015Co-Authors: Ricardo Suarezbertoa, A A Zardini, Velizara Lilova, Daniel Meyer, Shigeru Nakatani, Frank Hibel, Jens Ewers, Michael Clairotte, Leslie Hill, C AstorgaAbstract:Four light-duty vehicles (two diesel, one flex-fuel, and one gasoline vehicle) were Tested as part of an intercomparison exercise of the world-harmonized light-duty vehicle Test procedure (WLTP) aiming at measuring real-time ammonia emissions from the vehicles’ raw exhaust at the tailpipe. The Tests were conducted in the Vehicle Emission Laboratory (VELA) at the European Commission Joint Research Centre (EC-JRC), Ispra, Italy. HORIBA, CGS, and the Sustainable Transport Unit of the Joint Research Centre (JRC) took part in the measurement and analysis of the four vehicles’ exhaust emissions over the world-harmonized light-duty vehicle Test Cycle class 3, version 5.3 using a HORIBA MEXA 1400 QL-NX, a CGS BLAQ-Sys, and the JRC Fourier transform infrared spectrometer, respectively. The measured ammonia concentrations and the emission profiles revealed that these three instruments are suitable to measure ammonia from the vehicles’ raw exhaust, presenting no significant differences. Furthermore, results showed that measurement of ammonia from the vehicle exhaust using online systems can be performed guaranteeing the reproducibility and repeatability of the results. While no ammonia was detected for any of the two diesel vehicles (even though, one was equipped with a selective catalytic reduction system), we report average ammonia emission factors 8–10 mg/km (average concentrations 20–23 ppm) and 10–12 mg/km (average concentrations 22–24 ppm) for the flex-fuel and gasoline vehicles, respectively.
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impact of ethanol containing gasoline blends on emissions from a flex fuel vehicle Tested over the worldwide harmonized light duty Test Cycle wltc
Fuel, 2015Co-Authors: Ricardo Suarezbertoa, A A Zardini, H Keuken, C AstorgaAbstract:Abstract Regulated and unregulated emissions from a Euro 5a flex-fuel vehicle Tested with nine different hydrous and anhydrous ethanol containing fuel blends at 23 and −7 °C over the World harmonized Light-duty vehicle Test Cycle and the New European Driving Cycle, were investigated at the Vehicle Emission Laboratory at the European Commission Joint Research Centre Ispra, Italy. The experimental results showed no differences on the regulated and unregulated emissions when hydrous ethanol blends were used instead of anhydrous ethanol blends. The use of E85 and E75 blends (gasoline containing 85% and 75% of ethanol, respectively) resulted in a reduction of NO x emissions (30–55%) but increased the emissions of carbon monoxide, methane, carbonyls and ethanol compared to E5, E10 and E15 blends (gasoline containing 5%, 10% and 15% of ethanol, respectively). The increase of the acetaldehyde and ethanol emissions (up to 120% and 350% at 23 °C and up to 400% and 390% at −7 °C, for acetaldehyde and ethanol, respectively) caused a severe increment of the ozone formation potential. Most of the studied pollutants presented similar emission factors during the Tests performed with E10 and E15 blends. The emission factors of most unregulated compounds were lower over the NEDC (with ammonia as an exception) than over the WLTC. However, when taking into consideration only the cold start emissions, emission factors over the WLTC were observed to be higher, or similar, to those obtained over the NEDC. Low ambient temperature caused an increase of the emissions of all studied compounds with all Tested blends.
J.-c. Champoussin - One of the best experts on this subject based on the ideXlab platform.
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Optimal Control of a Variable Geometry Turbocharged Diesel Engine Using Neural Networks: Applications on the ETC Test Cycle
IEEE Transactions on Control Systems Technology, 2009Co-Authors: Rema Omran, Rafic Younes, J.-c. ChampoussinAbstract:Modern diesel engines are typically equipped with variable geometry turbo-compressor, exhaust gas recirculation (EGR) system, common rail injection system, and post-treatment devices in order to increase their power while respecting the emissions standards. Consequently, the control of diesel engines has become a difficult task involving five to ten control variables that interact with each other and that are highly nonlinear. Actually, the control schemes of the engines are all based on static lookup tables identified on Test-benches; the values of the control variables are interpolated using these tables and then, they are corrected, online, by using the control techniques in order to obtain better engine's response under dynamic conditions. In this paper, we are interested in developing a mathematical optimization process that search for the optimal control schemes of the diesel engines under static and dynamic conditions. First, we suggest modeling a turbocharged diesel engine and its opacity using the mean value model which requires limited experiments; the model's simulations are in excellent agreement with the experimental data. Then the created model is integrated in a dynamic optimization process based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The optimization results show the reduction of the opacity while enhancing the engine's effective power. Finally, we proposed a practical control technique based on the neural networks in order to apply these control schemes online to the engine. The neural controller is integrated into the engine's simulations and is used to control the engine in real time on the European transient Cycle (ETC). The results confirm the validity of the neural controller. View full abstract»
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Optimal Control of a Variable Geometry Turbocharged Diesel Engine Using Neural Networks: Applications on the ETC Test Cycle
IEEE Transactions on Control Systems Technology, 2009Co-Authors: Rema Omran, Rafic Younes, J.-c. ChampoussinAbstract:Modern diesel engines are typically equipped with variable geometry turbo-compressor, exhaust gas recirculation (EGR) system, common rail injection system, and post-treatment devices in order to increase their power while respecting the emissions standards. Consequently, the control of diesel engines has become a difficult task involving five to ten control variables that interact with each other and that are highly nonlinear. Actually, the control schemes of the engines are all based on static lookup tables identified on Test-benches; the values of the control variables are interpolated using these tables and then, they are corrected, online, by using the control techniques in order to obtain better engine's response under dynamic conditions. In this paper, we are interested in developing a mathematical optimization process that search for the optimal control schemes of the diesel engines under static and dynamic conditions. First, we suggest modeling a turbocharged diesel engine and its opacity using the mean value model which requires limited experiments; the model's simulations are in excellent agreement with the experimental data. Then the created model is integrated in a dynamic optimization process based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The optimization results show the reduction of the opacity while enhancing the engine's effective power. Finally, we proposed a practical control technique based on the neural networks in order to apply these control schemes online to the engine. The neural controller is integrated into the engine's simulations and is used to control the engine in real time on the European transient Cycle (ETC). The results confirm the validity of the neural controller.
Ricardo Suarezbertoa - One of the best experts on this subject based on the ideXlab platform.
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intercomparison of real time tailpipe ammonia measurements from vehicles Tested over the new world harmonized light duty vehicle Test Cycle wltc
Environmental Science and Pollution Research, 2015Co-Authors: Ricardo Suarezbertoa, A A Zardini, Velizara Lilova, Daniel Meyer, Shigeru Nakatani, Frank Hibel, Jens Ewers, Michael Clairotte, Leslie Hill, C AstorgaAbstract:Four light-duty vehicles (two diesel, one flex-fuel, and one gasoline vehicle) were Tested as part of an intercomparison exercise of the world-harmonized light-duty vehicle Test procedure (WLTP) aiming at measuring real-time ammonia emissions from the vehicles’ raw exhaust at the tailpipe. The Tests were conducted in the Vehicle Emission Laboratory (VELA) at the European Commission Joint Research Centre (EC-JRC), Ispra, Italy. HORIBA, CGS, and the Sustainable Transport Unit of the Joint Research Centre (JRC) took part in the measurement and analysis of the four vehicles’ exhaust emissions over the world-harmonized light-duty vehicle Test Cycle class 3, version 5.3 using a HORIBA MEXA 1400 QL-NX, a CGS BLAQ-Sys, and the JRC Fourier transform infrared spectrometer, respectively. The measured ammonia concentrations and the emission profiles revealed that these three instruments are suitable to measure ammonia from the vehicles’ raw exhaust, presenting no significant differences. Furthermore, results showed that measurement of ammonia from the vehicle exhaust using online systems can be performed guaranteeing the reproducibility and repeatability of the results. While no ammonia was detected for any of the two diesel vehicles (even though, one was equipped with a selective catalytic reduction system), we report average ammonia emission factors 8–10 mg/km (average concentrations 20–23 ppm) and 10–12 mg/km (average concentrations 22–24 ppm) for the flex-fuel and gasoline vehicles, respectively.
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impact of ethanol containing gasoline blends on emissions from a flex fuel vehicle Tested over the worldwide harmonized light duty Test Cycle wltc
Fuel, 2015Co-Authors: Ricardo Suarezbertoa, A A Zardini, H Keuken, C AstorgaAbstract:Abstract Regulated and unregulated emissions from a Euro 5a flex-fuel vehicle Tested with nine different hydrous and anhydrous ethanol containing fuel blends at 23 and −7 °C over the World harmonized Light-duty vehicle Test Cycle and the New European Driving Cycle, were investigated at the Vehicle Emission Laboratory at the European Commission Joint Research Centre Ispra, Italy. The experimental results showed no differences on the regulated and unregulated emissions when hydrous ethanol blends were used instead of anhydrous ethanol blends. The use of E85 and E75 blends (gasoline containing 85% and 75% of ethanol, respectively) resulted in a reduction of NO x emissions (30–55%) but increased the emissions of carbon monoxide, methane, carbonyls and ethanol compared to E5, E10 and E15 blends (gasoline containing 5%, 10% and 15% of ethanol, respectively). The increase of the acetaldehyde and ethanol emissions (up to 120% and 350% at 23 °C and up to 400% and 390% at −7 °C, for acetaldehyde and ethanol, respectively) caused a severe increment of the ozone formation potential. Most of the studied pollutants presented similar emission factors during the Tests performed with E10 and E15 blends. The emission factors of most unregulated compounds were lower over the NEDC (with ammonia as an exception) than over the WLTC. However, when taking into consideration only the cold start emissions, emission factors over the WLTC were observed to be higher, or similar, to those obtained over the NEDC. Low ambient temperature caused an increase of the emissions of all studied compounds with all Tested blends.
Rema Omran - One of the best experts on this subject based on the ideXlab platform.
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Optimal Control of a Variable Geometry Turbocharged Diesel Engine Using Neural Networks: Applications on the ETC Test Cycle
IEEE Transactions on Control Systems Technology, 2009Co-Authors: Rema Omran, Rafic Younes, J.-c. ChampoussinAbstract:Modern diesel engines are typically equipped with variable geometry turbo-compressor, exhaust gas recirculation (EGR) system, common rail injection system, and post-treatment devices in order to increase their power while respecting the emissions standards. Consequently, the control of diesel engines has become a difficult task involving five to ten control variables that interact with each other and that are highly nonlinear. Actually, the control schemes of the engines are all based on static lookup tables identified on Test-benches; the values of the control variables are interpolated using these tables and then, they are corrected, online, by using the control techniques in order to obtain better engine's response under dynamic conditions. In this paper, we are interested in developing a mathematical optimization process that search for the optimal control schemes of the diesel engines under static and dynamic conditions. First, we suggest modeling a turbocharged diesel engine and its opacity using the mean value model which requires limited experiments; the model's simulations are in excellent agreement with the experimental data. Then the created model is integrated in a dynamic optimization process based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The optimization results show the reduction of the opacity while enhancing the engine's effective power. Finally, we proposed a practical control technique based on the neural networks in order to apply these control schemes online to the engine. The neural controller is integrated into the engine's simulations and is used to control the engine in real time on the European transient Cycle (ETC). The results confirm the validity of the neural controller. View full abstract»
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Optimal Control of a Variable Geometry Turbocharged Diesel Engine Using Neural Networks: Applications on the ETC Test Cycle
IEEE Transactions on Control Systems Technology, 2009Co-Authors: Rema Omran, Rafic Younes, J.-c. ChampoussinAbstract:Modern diesel engines are typically equipped with variable geometry turbo-compressor, exhaust gas recirculation (EGR) system, common rail injection system, and post-treatment devices in order to increase their power while respecting the emissions standards. Consequently, the control of diesel engines has become a difficult task involving five to ten control variables that interact with each other and that are highly nonlinear. Actually, the control schemes of the engines are all based on static lookup tables identified on Test-benches; the values of the control variables are interpolated using these tables and then, they are corrected, online, by using the control techniques in order to obtain better engine's response under dynamic conditions. In this paper, we are interested in developing a mathematical optimization process that search for the optimal control schemes of the diesel engines under static and dynamic conditions. First, we suggest modeling a turbocharged diesel engine and its opacity using the mean value model which requires limited experiments; the model's simulations are in excellent agreement with the experimental data. Then the created model is integrated in a dynamic optimization process based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The optimization results show the reduction of the opacity while enhancing the engine's effective power. Finally, we proposed a practical control technique based on the neural networks in order to apply these control schemes online to the engine. The neural controller is integrated into the engine's simulations and is used to control the engine in real time on the European transient Cycle (ETC). The results confirm the validity of the neural controller.
Hoon Kiat Ng - One of the best experts on this subject based on the ideXlab platform.
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A NOVEL STEADY-STATE Test Cycle FOR EMISSIONS CHARACTERISATION OF A LIGHT-DUTY DIESEL ENGINE FUELLED WITH BIODIESEL
Chemical Biological and Environmental Engineering, 2020Co-Authors: Jo-han Ng, Hoon Kiat Ng, Jourabchi Seyed AmirmostafaAbstract:The environmental impacts of diesel emissions coupled with the imminent depletion of petroleum, has led to extensive research efforts on alternative fuels. Biodiesel has emerged as the favoured alternative fuel for diesel engine. With this in mind, comprehensive emissions mapping would be required to ascertain the effectiveness of biodiesel in emissions reduction. In this experimental study, a modified steady-state heavy-duty diesel engine Test Cycle was used. Test point reduction was proposed to reduce the time required within an acceptable reduction in accuracy of the Test data. Using the reduced Test Cycle, the effects of biodiesel from palm, soybean and coconut on tailpipe emissions were compared against that of conventional diesel.
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engine out characterisation using speed load mapping and reduced Test Cycle for a light duty diesel engine fuelled with biodiesel blends
Fuel, 2011Co-Authors: Jo-han Ng, Hoon Kiat NgAbstract:Abstract In this two-phase experimental programme, key effects of different biodiesel fuels and their blends on engine-out responses of a light-duty diesel engine were investigated. Here, coconut methyl ester (CME), palm methyl ester (PME) and soybean methyl ester (SME) were Tested to represent the wide spectrum of degree of saturations in the fatty acid composition. Fossil diesel which served as the blending component was used as the baseline fuel for benchmarking purposes. Phase I examined how engine speed and load affect patterns of variation in tailpipe emissions and engine performance parameters for the Test fuels. Here, the trends in engine-out responses across the operational speed–load map for all the Tested biodiesel fuels were similar and consistent throughout. However, there were marked differences in the levels of equivalence ratio and specific fuel consumption, as well as exhaust concentrations of CO, UHC and smoke opacity. This is mainly due to differences in fuel properties, especially fuel-bound oxygen content, density and impurity level. Phase II appraised the performance of 31 different fuel blend combinations of fossil diesel blended with CME, PME or SME at 10 vol.% interval under a steady-state Test Cycle. The use of biodiesel fuels with low to moderate degree of unsaturation was found to conclusively reduce regulated emission species of UHC, NO and smoke opacity levels by up to 41.7%, 5.4% and 61.3%, respectively. This is in contrast to the performance of the highly unsaturated SME, where CO, UHC, NO and smoke opacity levels are higher in relation to that of fossil diesel. Simultaneous NO–smoke reduction can be achieved through the introduction of at least 1 vol.% of PME or 50 vol.% of CME into diesel fuel, although minor trade-off in the higher specific fuel consumption is observed.
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Engine-out characterisation using speed–load mapping and reduced Test Cycle for a light-duty diesel engine fuelled with biodiesel blends
Fuel, 2011Co-Authors: Jo-han Ng, Hoon Kiat NgAbstract:Abstract In this two-phase experimental programme, key effects of different biodiesel fuels and their blends on engine-out responses of a light-duty diesel engine were investigated. Here, coconut methyl ester (CME), palm methyl ester (PME) and soybean methyl ester (SME) were Tested to represent the wide spectrum of degree of saturations in the fatty acid composition. Fossil diesel which served as the blending component was used as the baseline fuel for benchmarking purposes. Phase I examined how engine speed and load affect patterns of variation in tailpipe emissions and engine performance parameters for the Test fuels. Here, the trends in engine-out responses across the operational speed–load map for all the Tested biodiesel fuels were similar and consistent throughout. However, there were marked differences in the levels of equivalence ratio and specific fuel consumption, as well as exhaust concentrations of CO, UHC and smoke opacity. This is mainly due to differences in fuel properties, especially fuel-bound oxygen content, density and impurity level. Phase II appraised the performance of 31 different fuel blend combinations of fossil diesel blended with CME, PME or SME at 10 vol.% interval under a steady-state Test Cycle. The use of biodiesel fuels with low to moderate degree of unsaturation was found to conclusively reduce regulated emission species of UHC, NO and smoke opacity levels by up to 41.7%, 5.4% and 61.3%, respectively. This is in contrast to the performance of the highly unsaturated SME, where CO, UHC, NO and smoke opacity levels are higher in relation to that of fossil diesel. Simultaneous NO–smoke reduction can be achieved through the introduction of at least 1 vol.% of PME or 50 vol.% of CME into diesel fuel, although minor trade-off in the higher specific fuel consumption is observed.
