Pierre Comte - Academia.edu (original) (raw)

Papers by Pierre Comte

Atmospheric Chemistry and Physics, 2018

Gasoline direct injection (GDI) vehicles have recently been identified as a significant source of... more Gasoline direct injection (GDI) vehicles have recently been identified as a significant source of carbonaceous aerosol, of both primary and secondary origin. Here we investigated primary emissions and secondary organic aerosol (SOA) from four GDI vehicles, two of which were also retrofitted with a prototype gasoline particulate filter (GPF). We studied two driving test cycles under cold-and hotengine conditions. Emissions were characterized by proton transfer reaction time-of-flight mass spectrometry (gaseous non-methane organic compounds, NMOCs), aerosol mass spectrometry (sub-micron non-refractory particles) and light attenuation measurements (equivalent black carbon (eBC) determination using Aethalometers) together with supporting instrumentation. Atmospheric processing was simulated using the PSI mobile smog chamber (SC) and the potential aerosol mass oxidation flow reactor (OFR). Overall, primary and secondary particulate matter (PM) and NMOC emissions were dominated by the engine cold start, i.e., before thermal activation of the catalytic after-treatment system. Trends in the SOA oxygen to carbon ratio (O : C) for OFR and SC were related to different OH exposures, but divergences in the H : C remained unexplained. SOA yields agreed within experimental variability between the two systems, with a tendency for higher values in the OFR than in the SC (or, vice versa, lower values in the SC). A few aromatic compounds dominated the NMOC emissions, primarily benzene, toluene, xylene isomers/ethylbenzene and C3-benzene. A significant fraction of the SOA was explained by those compounds, based on comparison of effective SOA yield curves with those of toluene, o-xylene and 1,2,4-trimethylbenzene determined in our OFR, as well as others from literature. Remaining discrepancies, which were smaller in the SC and larger in the OFR, were up to a factor of 2 and may have resulted from diverse reasons including unaccounted precursors and matrix effects. GPF retrofitting significantly reduced primary PM through removal of refractory eBC and partially removed the minor POA fraction. At cold-started conditions it did not affect hydrocarbon emission factors, relative chemical composition of NMOCs or SOA formation, and likewise SOA yields and bulk composition remained unaffected. GPFinduced effects at hot-engine conditions deserve attention in further studies.

Environmental research, 2016

Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almos... more Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almost all gasoline cars can drive with fuel containing 10% ethanol (E10), flex-fuel cars can even use 85% ethanol (E85). Brazil and the USA already include 10-27% ethanol in their standard fuel by law. Most health effect studies on car emissions are however performed with diesel exhausts, and only few data exists for other fuels. In this work we investigated possible toxic effects of exhaust aerosols from ethanol-gasoline blends using a multi-cellular model of the human lung. A flex-fuel passenger car was driven on a chassis dynamometer and fueled with E10, E85, or pure gasoline (E0). Exhausts obtained from a steady state cycle were directly applied for 6h at a dilution of 1:10 onto a multi-cellular human lung model mimicking the bronchial compartment composed of human bronchial cells (16HBE14o-), supplemented with human monocyte-derived dendritic cells and monocyte-derived macrophages, cult...

Atmospheric Environment, 2015

h i g h l i g h t s No substantial reduction in UFP formation for newer bus generations. UFP numb... more h i g h l i g h t s No substantial reduction in UFP formation for newer bus generations. UFP number concentrations decrease with the power rise at a constant engine speed. Strong correlation between PNC under steady-state and free acceleration regimes. Filtration efficiency values of the retrofit DPF were found to be above 99.8%.

Atmospheric Environment, 2013

Atmospheric Environment, 2013

A non-catalyzed DPF decreases the oxidative potential of diesel exhaust. Inhalation of diesel exh... more A non-catalyzed DPF decreases the oxidative potential of diesel exhaust. Inhalation of diesel exhaust induces severe oxidative stress in vitro. Unfiltered diesel exhaust induces acute pro-inflammatory responses in vitro. Filtered diesel exhaust does not induce acute pro-inflammation in vitro. Exhaust filtration alone is not sufficient to reduce in vitro diesel exhaust toxicity.

Environmental science & technology, Nov 7, 2016

Bioethanol as an alternative fuel is widely used as a substitute for gasoline, also in gasoline d... more Bioethanol as an alternative fuel is widely used as a substitute for gasoline, also in gasoline direct injection (GDI) vehicles, which are quickly replacing traditional port-fuel injection (PFI) vehicles. Better fuel efficiency and increased engine power are reported advantages of GDI-vehicles. But increased emissions of soot-like nanoparticles are also associated with the GDI-technology with yet unknown health impact. In this study, we compare emissions of a flex-fuel Euro-5 GDI-vehicle operated with gasoline (E0) and two ethanol/gasoline blends (E10 and E85) under transient and steady driving conditions and report effects on particle, polycyclic aromatic hydrocarbon (PAH), alkyl- and nitro-PAH emissions and assess the genotoxic potential of them. Particle number (PN) emissions were lowered by 97% and 96% when operating the vehicle in the hWLTC (hot started worldwide harmonized light-duty vehicle test cycle) with E10 and E85 compared with E0. CO emissions dropped by 81 and 87%, whi...

Combustion Engines, 2011

The objectives of the present work are to investigate the regulated and unregulated (particle) em... more The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nanoparticles counts (NP) were carried out. The present investigations did not c...

Combustion Engines, Dec 15, 2020

Biofuels represent one of the alternatives to obtain the CO 2-neutral propulsion of IC-engines. B... more Biofuels represent one of the alternatives to obtain the CO 2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels. This paper presents the emission results obtained on two diesel passenger cars with different technology (Euro 2 and Euro 6c) and with addition of butanol to diesel fuel, as a part of the research project DiBut (diesel and butanol). Interesting results are given about some non-legislated (non-regulated) components, acetaldehyde (MeCHO) and formaldehyde (HCHO) and about the PN-emissions with/without DPF.

Investigations of nanoparticle emissions of two gasoline cars MPI & DI at stationary part load op... more Investigations of nanoparticle emissions of two gasoline cars MPI & DI at stationary part load operation Starting from Euro 6 not only for diesel but also for gasoline vehicles, with direct injection technology (GDI) a solid particle number emissions limit of 6 × 10 11 #/km becomes effective. The limit was temporary extended for GDI to 6 x 10 12 #/km. Nuclei of metals as well as organics are suspected to significantly contribute especially to the ultrafine particle size fractions, and thus to the particle number concentration. In the project GasOMeP (Gasoline Organic & Metal Particulates) metal-nanoparticles (including sub 20 nm) from gasoline cars are investigated for different engine technologies. In the present paper some results of basic investigations of nanoparticles from two gasoline cars-an older one with MPI and a never one with DI-are represented. The measurements were performed at vehicle tailpipe, with varying sampling conditions and with different SMPS-systems, which enabled the mobility scanning in different size ranges. The results show that the older vehicle with MPI emits high particle count concentrations. The size distributions are decisively bimodal with high numbers in nuclei mode. In this case, the particle counting below 10 nm yields important information. The emissions of the newer vehicle with DI show no typical uniform shape of particle size distributions and are at lower level, than for the older vehicle. There is no visible nuclei mode and the ultrafine particle concentrations below 10 nm are insignificant. A sampling with a strongly increased primary dilution has a clear influence on the indicated (higher) particle concentrations.

SAE Technical Paper Series, 2007

SAE Technical Paper Series, 2006

ABSTRACT Limited and nonlimited emissions of scooters were analyzed during several annual researc... more ABSTRACT Limited and nonlimited emissions of scooters were analyzed during several annual research programs of the Swiss Agency of Environment Forests and Landscape (SAEFL, BUWAL). Small scooters, which are very much used in the congested centers of several cities are a remarkable source of air pollution. Therefore every effort to reduce the emissions is an important contribution to improve the air quality in urban centers. In the present work detailed investigations of particle emissions of different 2-stroke scooters with direct injection and with carburetor were performed. The nanoparticulate emissions with different lube oils and fuels were measured by means of SMPS, (CPC) and NanoMet. Also the particle mass emission (PM) was measured with the same method as for Diesel engines. Extensive analyses of PM-residuum for PAH & SOF/INSOF, as well as for VOC were carried out in an international project network. It can be stated, that the oil and fuel quality have a considerable influence on the particle emissions, which are mainly oil condensates. The engine technol. influences the (nano)particle emissions by: mixt. prepn., mixt. tuning, oil consumption, postoxidn., quality, condition and temp. of the catalyst. Since the particulate emission of the 2-S consists mainly of lube oil condensates the minimization of oil consumption stays always an important goal. The amt. of total PAH, as well as the toxicity equivalence factor TEQ correlate roughly with the total particle mass PM. [on SciFinder(R)]

SAE Technical Paper Series, 2018

urther efforts to reduce the air pollution from traffic are undertaken worldwide and the filtrati... more urther efforts to reduce the air pollution from traffic are undertaken worldwide and the filtration of exhaust gas will also be increasingly applied on gasoline cars (GPF * … gasoline particle filter). In the present paper, some results of investigations of nanoparticles from four MPI gasoline cars are represented. The measurements were performed at vehicle tailpipe and in CVS-tunnel. Moreover, two variants of GPF were * Abbreviations see at the end of this paper. investigated on a high-emitting modern vehicle, including analytics of PAH and attempts of soot loading in road application. The modern MPI vehicles can emit a considerable amount of PN, which in some cases attains the level of Diesel exhaust gas without DPF and can pass over the actual European limit value for GDI (6.0 × 10 11 #/km). The GPF-technology offers in this respect further potentials to reduce the PN-emissions of traffic. With GPF, in the investigated steady state operation, there is no significant visible nuclei mode and the ultrafine particles concentrations below 10 nm size are insignificant.

Combustion Engines

The nanoparticles (NP) count concentrations are limited in EU for all Diesel passenger cars since... more The nanoparticles (NP) count concentrations are limited in EU for all Diesel passenger cars since 2013 and for gasoline cars with direct injection (GDI) since 2014. For the particle number (PN) of MPI gasoline cars there are still no legal limitations. In the present paper some results of investigations of nanoparticles from five DI and four MPI gasoline cars are represented. The measurements were performed at vehicle tailpipe and in CVS-tunnel. Moreover, five variants of “vehicle – GPF” were investigated. The PN-emission level of the investigated GDI cars in WLTC without GPF is in the same range of magnitude very near to the actual limit value of 6.0 × 10^12 1/km. With the GPF’s with better filtration quality, it is possible to lower the emissions below the future limit value of 6.0 × 10^11 1/km. The modern MPI vehicles also emit a considerable amount of PN, which in some cases can attain the level of Diesel exhaust gas without DPF and can pass over the actual limit value for GDI (...

Combustion Engines, 2016

In the present paper, the results and experiences of testing different PEMS on the chassis dynamo... more In the present paper, the results and experiences of testing different PEMS on the chassis dynamometer and on-road are presented. In the first part of work the measuring systems were installed on the same vehicle (Seat Leon 1.4 TSI ST) and the results were compared on the chassis dynamometer in the standard test cycles: NEDC, WLTC and CADC. in the second part of work the nanoparticle emissions of three Diesel cars were measured with PN-PEMS. PN-PEMS showed an excellent correlations with CPC in the tests on chassis dynamometer and it indicated very well the efficiency of DPF in eliminating the nanoparticles in real world driving.

Increasing the sustainability of individual transportation and replacing a part of fossil energy ... more Increasing the sustainability of individual transportation and replacing a part of fossil energy in traffic by renewable energy carriers are worldwide important objectives. Bioalcohols are generally recognized as one of very useful alternatives. The global share of bioethanol used for transportation is continuously increasing. Butanol, a four-carbon alcohol, is considered in the last years as an interesting alternative fuel, both for diesel and for gasoline application. Its advantages for engine operation are: good miscibility with gasoline and diesel fuels, higher calorific value than ethanol, lower hygroscopicity, lower corrosivity and possibility of replacing aviation fuels. In the present work, the emissions of two gasoline vehicles – with older and with newer technology – were investigated in dynamic-, stationary and cold start operation.

Journal of KONES, 2017

The particle number (PN) emissions are increasingly considered in the progressing exhaust gas leg... more The particle number (PN) emissions are increasingly considered in the progressing exhaust gas legislation for onand off-road vehicles. The invisible nanoparticles penetrate like a gas into the living organisms and cause several health hazards. The present paper shows how the PN- and gaseous emissions of a modern GDI (Abbreviations see sat the end of this paper) vehicle change, when there is an in-creased lube oil consumption. What are the potentials of a gasoline particle filter to reduce the emissions? The lube oil consumption was simulated by mixing 2% vol. lube oil into the fuel. A non-coated GPF was mounted at tailpipe, so only the filtration effects were indicated. The tests were performed at transient (WLTC) and at stationary (SSC) operating conditions. It has been shown that the increased lube oil consumption significantly increases the PN-emissions and the applied high quality GPF eliminates these emissions very efficiently.

Four of these Particulate Reduction Systems (PMS) were tested on a passenger car and one of them ... more Four of these Particulate Reduction Systems (PMS) were tested on a passenger car and one of them on a HDV. Expectation of the research team was that they would reach at least a PM-reduction of 30% under all realistic operating conditions. The standard German filter test procedure for PMS was performed but moreover, the response to various operating conditions was tested including worst case situations. Besides the legislated CO, NOx and PM exhaust-gas emissions, also the particle count and NO2 were measured. The best filtration efficiency with one PMS was indeed 63%. However, under critical but realistic conditions filtration of 3 of 4 PMS was measured substantially lower than the expected 30 %, depending on operating conditions and prior history, and could even completely fail. Scatter between repeated cycles was very large and results were not reproducible. Even worse, with all 4 PMS deposited soot, stored in these systems during light load operation was intermittently blown-off. ...

Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Bu... more Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels. This paper presents the emission results obtained on two diesel passenger cars with different technology (Euro 2 and Euro 6c) and with addition of butanol to diesel fuel, as a part of the research project DiBut (diesel and butanol). Interesting results are given about some non-legislated (non-regulated) components, acetaldehyde (MeCHO) and formaldehyde (HCHO) and about the PN-emissions with/without DPF.

Combustion Engines

Testing of real driving emissions (RDE) offers the opportunity to collect the data about the emis... more Testing of real driving emissions (RDE) offers the opportunity to collect the data about the emissions in special driving, or non-driving situations. These situations are: cold start, warm-up of the engine, stop & go and idling. In the present work, the definitions of the special driving situations were proposed, the emissions of 7 passenger cars (gasoline & Diesel) were extracted from the present RDE data and some special driving situations, particularly the stop & go operation with varying share of idling were reproduced on chassis dynamometer. As expected, the emissions of CO, NOx and PN are in the cold start and in the first part of the warm-up phase (c.a. 25s) considerably higher than in the rest of the investigated urban phase. The singular emitting situations like “stop & go” or idling occur frequently in the warm-up phase, i.e. in the city operation when the engine and the exhaust system are still not warm enough.

Atmospheric Chemistry and Physics, 2018

Gasoline direct injection (GDI) vehicles have recently been identified as a significant source of... more Gasoline direct injection (GDI) vehicles have recently been identified as a significant source of carbonaceous aerosol, of both primary and secondary origin. Here we investigated primary emissions and secondary organic aerosol (SOA) from four GDI vehicles, two of which were also retrofitted with a prototype gasoline particulate filter (GPF). We studied two driving test cycles under cold-and hotengine conditions. Emissions were characterized by proton transfer reaction time-of-flight mass spectrometry (gaseous non-methane organic compounds, NMOCs), aerosol mass spectrometry (sub-micron non-refractory particles) and light attenuation measurements (equivalent black carbon (eBC) determination using Aethalometers) together with supporting instrumentation. Atmospheric processing was simulated using the PSI mobile smog chamber (SC) and the potential aerosol mass oxidation flow reactor (OFR). Overall, primary and secondary particulate matter (PM) and NMOC emissions were dominated by the engine cold start, i.e., before thermal activation of the catalytic after-treatment system. Trends in the SOA oxygen to carbon ratio (O : C) for OFR and SC were related to different OH exposures, but divergences in the H : C remained unexplained. SOA yields agreed within experimental variability between the two systems, with a tendency for higher values in the OFR than in the SC (or, vice versa, lower values in the SC). A few aromatic compounds dominated the NMOC emissions, primarily benzene, toluene, xylene isomers/ethylbenzene and C3-benzene. A significant fraction of the SOA was explained by those compounds, based on comparison of effective SOA yield curves with those of toluene, o-xylene and 1,2,4-trimethylbenzene determined in our OFR, as well as others from literature. Remaining discrepancies, which were smaller in the SC and larger in the OFR, were up to a factor of 2 and may have resulted from diverse reasons including unaccounted precursors and matrix effects. GPF retrofitting significantly reduced primary PM through removal of refractory eBC and partially removed the minor POA fraction. At cold-started conditions it did not affect hydrocarbon emission factors, relative chemical composition of NMOCs or SOA formation, and likewise SOA yields and bulk composition remained unaffected. GPFinduced effects at hot-engine conditions deserve attention in further studies.

Environmental research, 2016

Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almos... more Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almost all gasoline cars can drive with fuel containing 10% ethanol (E10), flex-fuel cars can even use 85% ethanol (E85). Brazil and the USA already include 10-27% ethanol in their standard fuel by law. Most health effect studies on car emissions are however performed with diesel exhausts, and only few data exists for other fuels. In this work we investigated possible toxic effects of exhaust aerosols from ethanol-gasoline blends using a multi-cellular model of the human lung. A flex-fuel passenger car was driven on a chassis dynamometer and fueled with E10, E85, or pure gasoline (E0). Exhausts obtained from a steady state cycle were directly applied for 6h at a dilution of 1:10 onto a multi-cellular human lung model mimicking the bronchial compartment composed of human bronchial cells (16HBE14o-), supplemented with human monocyte-derived dendritic cells and monocyte-derived macrophages, cult...

Atmospheric Environment, 2015

h i g h l i g h t s No substantial reduction in UFP formation for newer bus generations. UFP numb... more h i g h l i g h t s No substantial reduction in UFP formation for newer bus generations. UFP number concentrations decrease with the power rise at a constant engine speed. Strong correlation between PNC under steady-state and free acceleration regimes. Filtration efficiency values of the retrofit DPF were found to be above 99.8%.

Atmospheric Environment, 2013

Atmospheric Environment, 2013

A non-catalyzed DPF decreases the oxidative potential of diesel exhaust. Inhalation of diesel exh... more A non-catalyzed DPF decreases the oxidative potential of diesel exhaust. Inhalation of diesel exhaust induces severe oxidative stress in vitro. Unfiltered diesel exhaust induces acute pro-inflammatory responses in vitro. Filtered diesel exhaust does not induce acute pro-inflammation in vitro. Exhaust filtration alone is not sufficient to reduce in vitro diesel exhaust toxicity.

Environmental science & technology, Nov 7, 2016

Bioethanol as an alternative fuel is widely used as a substitute for gasoline, also in gasoline d... more Bioethanol as an alternative fuel is widely used as a substitute for gasoline, also in gasoline direct injection (GDI) vehicles, which are quickly replacing traditional port-fuel injection (PFI) vehicles. Better fuel efficiency and increased engine power are reported advantages of GDI-vehicles. But increased emissions of soot-like nanoparticles are also associated with the GDI-technology with yet unknown health impact. In this study, we compare emissions of a flex-fuel Euro-5 GDI-vehicle operated with gasoline (E0) and two ethanol/gasoline blends (E10 and E85) under transient and steady driving conditions and report effects on particle, polycyclic aromatic hydrocarbon (PAH), alkyl- and nitro-PAH emissions and assess the genotoxic potential of them. Particle number (PN) emissions were lowered by 97% and 96% when operating the vehicle in the hWLTC (hot started worldwide harmonized light-duty vehicle test cycle) with E10 and E85 compared with E0. CO emissions dropped by 81 and 87%, whi...

Combustion Engines, 2011

The objectives of the present work are to investigate the regulated and unregulated (particle) em... more The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nanoparticles counts (NP) were carried out. The present investigations did not c...

Combustion Engines, Dec 15, 2020

Biofuels represent one of the alternatives to obtain the CO 2-neutral propulsion of IC-engines. B... more Biofuels represent one of the alternatives to obtain the CO 2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels. This paper presents the emission results obtained on two diesel passenger cars with different technology (Euro 2 and Euro 6c) and with addition of butanol to diesel fuel, as a part of the research project DiBut (diesel and butanol). Interesting results are given about some non-legislated (non-regulated) components, acetaldehyde (MeCHO) and formaldehyde (HCHO) and about the PN-emissions with/without DPF.

Investigations of nanoparticle emissions of two gasoline cars MPI & DI at stationary part load op... more Investigations of nanoparticle emissions of two gasoline cars MPI & DI at stationary part load operation Starting from Euro 6 not only for diesel but also for gasoline vehicles, with direct injection technology (GDI) a solid particle number emissions limit of 6 × 10 11 #/km becomes effective. The limit was temporary extended for GDI to 6 x 10 12 #/km. Nuclei of metals as well as organics are suspected to significantly contribute especially to the ultrafine particle size fractions, and thus to the particle number concentration. In the project GasOMeP (Gasoline Organic & Metal Particulates) metal-nanoparticles (including sub 20 nm) from gasoline cars are investigated for different engine technologies. In the present paper some results of basic investigations of nanoparticles from two gasoline cars-an older one with MPI and a never one with DI-are represented. The measurements were performed at vehicle tailpipe, with varying sampling conditions and with different SMPS-systems, which enabled the mobility scanning in different size ranges. The results show that the older vehicle with MPI emits high particle count concentrations. The size distributions are decisively bimodal with high numbers in nuclei mode. In this case, the particle counting below 10 nm yields important information. The emissions of the newer vehicle with DI show no typical uniform shape of particle size distributions and are at lower level, than for the older vehicle. There is no visible nuclei mode and the ultrafine particle concentrations below 10 nm are insignificant. A sampling with a strongly increased primary dilution has a clear influence on the indicated (higher) particle concentrations.

SAE Technical Paper Series, 2007

SAE Technical Paper Series, 2006

ABSTRACT Limited and nonlimited emissions of scooters were analyzed during several annual researc... more ABSTRACT Limited and nonlimited emissions of scooters were analyzed during several annual research programs of the Swiss Agency of Environment Forests and Landscape (SAEFL, BUWAL). Small scooters, which are very much used in the congested centers of several cities are a remarkable source of air pollution. Therefore every effort to reduce the emissions is an important contribution to improve the air quality in urban centers. In the present work detailed investigations of particle emissions of different 2-stroke scooters with direct injection and with carburetor were performed. The nanoparticulate emissions with different lube oils and fuels were measured by means of SMPS, (CPC) and NanoMet. Also the particle mass emission (PM) was measured with the same method as for Diesel engines. Extensive analyses of PM-residuum for PAH & SOF/INSOF, as well as for VOC were carried out in an international project network. It can be stated, that the oil and fuel quality have a considerable influence on the particle emissions, which are mainly oil condensates. The engine technol. influences the (nano)particle emissions by: mixt. prepn., mixt. tuning, oil consumption, postoxidn., quality, condition and temp. of the catalyst. Since the particulate emission of the 2-S consists mainly of lube oil condensates the minimization of oil consumption stays always an important goal. The amt. of total PAH, as well as the toxicity equivalence factor TEQ correlate roughly with the total particle mass PM. [on SciFinder(R)]

SAE Technical Paper Series, 2018

urther efforts to reduce the air pollution from traffic are undertaken worldwide and the filtrati... more urther efforts to reduce the air pollution from traffic are undertaken worldwide and the filtration of exhaust gas will also be increasingly applied on gasoline cars (GPF * … gasoline particle filter). In the present paper, some results of investigations of nanoparticles from four MPI gasoline cars are represented. The measurements were performed at vehicle tailpipe and in CVS-tunnel. Moreover, two variants of GPF were * Abbreviations see at the end of this paper. investigated on a high-emitting modern vehicle, including analytics of PAH and attempts of soot loading in road application. The modern MPI vehicles can emit a considerable amount of PN, which in some cases attains the level of Diesel exhaust gas without DPF and can pass over the actual European limit value for GDI (6.0 × 10 11 #/km). The GPF-technology offers in this respect further potentials to reduce the PN-emissions of traffic. With GPF, in the investigated steady state operation, there is no significant visible nuclei mode and the ultrafine particles concentrations below 10 nm size are insignificant.

Combustion Engines

The nanoparticles (NP) count concentrations are limited in EU for all Diesel passenger cars since... more The nanoparticles (NP) count concentrations are limited in EU for all Diesel passenger cars since 2013 and for gasoline cars with direct injection (GDI) since 2014. For the particle number (PN) of MPI gasoline cars there are still no legal limitations. In the present paper some results of investigations of nanoparticles from five DI and four MPI gasoline cars are represented. The measurements were performed at vehicle tailpipe and in CVS-tunnel. Moreover, five variants of “vehicle – GPF” were investigated. The PN-emission level of the investigated GDI cars in WLTC without GPF is in the same range of magnitude very near to the actual limit value of 6.0 × 10^12 1/km. With the GPF’s with better filtration quality, it is possible to lower the emissions below the future limit value of 6.0 × 10^11 1/km. The modern MPI vehicles also emit a considerable amount of PN, which in some cases can attain the level of Diesel exhaust gas without DPF and can pass over the actual limit value for GDI (...

Combustion Engines, 2016

In the present paper, the results and experiences of testing different PEMS on the chassis dynamo... more In the present paper, the results and experiences of testing different PEMS on the chassis dynamometer and on-road are presented. In the first part of work the measuring systems were installed on the same vehicle (Seat Leon 1.4 TSI ST) and the results were compared on the chassis dynamometer in the standard test cycles: NEDC, WLTC and CADC. in the second part of work the nanoparticle emissions of three Diesel cars were measured with PN-PEMS. PN-PEMS showed an excellent correlations with CPC in the tests on chassis dynamometer and it indicated very well the efficiency of DPF in eliminating the nanoparticles in real world driving.

Increasing the sustainability of individual transportation and replacing a part of fossil energy ... more Increasing the sustainability of individual transportation and replacing a part of fossil energy in traffic by renewable energy carriers are worldwide important objectives. Bioalcohols are generally recognized as one of very useful alternatives. The global share of bioethanol used for transportation is continuously increasing. Butanol, a four-carbon alcohol, is considered in the last years as an interesting alternative fuel, both for diesel and for gasoline application. Its advantages for engine operation are: good miscibility with gasoline and diesel fuels, higher calorific value than ethanol, lower hygroscopicity, lower corrosivity and possibility of replacing aviation fuels. In the present work, the emissions of two gasoline vehicles – with older and with newer technology – were investigated in dynamic-, stationary and cold start operation.

Journal of KONES, 2017

The particle number (PN) emissions are increasingly considered in the progressing exhaust gas leg... more The particle number (PN) emissions are increasingly considered in the progressing exhaust gas legislation for onand off-road vehicles. The invisible nanoparticles penetrate like a gas into the living organisms and cause several health hazards. The present paper shows how the PN- and gaseous emissions of a modern GDI (Abbreviations see sat the end of this paper) vehicle change, when there is an in-creased lube oil consumption. What are the potentials of a gasoline particle filter to reduce the emissions? The lube oil consumption was simulated by mixing 2% vol. lube oil into the fuel. A non-coated GPF was mounted at tailpipe, so only the filtration effects were indicated. The tests were performed at transient (WLTC) and at stationary (SSC) operating conditions. It has been shown that the increased lube oil consumption significantly increases the PN-emissions and the applied high quality GPF eliminates these emissions very efficiently.

Four of these Particulate Reduction Systems (PMS) were tested on a passenger car and one of them ... more Four of these Particulate Reduction Systems (PMS) were tested on a passenger car and one of them on a HDV. Expectation of the research team was that they would reach at least a PM-reduction of 30% under all realistic operating conditions. The standard German filter test procedure for PMS was performed but moreover, the response to various operating conditions was tested including worst case situations. Besides the legislated CO, NOx and PM exhaust-gas emissions, also the particle count and NO2 were measured. The best filtration efficiency with one PMS was indeed 63%. However, under critical but realistic conditions filtration of 3 of 4 PMS was measured substantially lower than the expected 30 %, depending on operating conditions and prior history, and could even completely fail. Scatter between repeated cycles was very large and results were not reproducible. Even worse, with all 4 PMS deposited soot, stored in these systems during light load operation was intermittently blown-off. ...

Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Bu... more Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels. This paper presents the emission results obtained on two diesel passenger cars with different technology (Euro 2 and Euro 6c) and with addition of butanol to diesel fuel, as a part of the research project DiBut (diesel and butanol). Interesting results are given about some non-legislated (non-regulated) components, acetaldehyde (MeCHO) and formaldehyde (HCHO) and about the PN-emissions with/without DPF.

Combustion Engines

Testing of real driving emissions (RDE) offers the opportunity to collect the data about the emis... more Testing of real driving emissions (RDE) offers the opportunity to collect the data about the emissions in special driving, or non-driving situations. These situations are: cold start, warm-up of the engine, stop & go and idling. In the present work, the definitions of the special driving situations were proposed, the emissions of 7 passenger cars (gasoline & Diesel) were extracted from the present RDE data and some special driving situations, particularly the stop & go operation with varying share of idling were reproduced on chassis dynamometer. As expected, the emissions of CO, NOx and PN are in the cold start and in the first part of the warm-up phase (c.a. 25s) considerably higher than in the rest of the investigated urban phase. The singular emitting situations like “stop & go” or idling occur frequently in the warm-up phase, i.e. in the city operation when the engine and the exhaust system are still not warm enough.