Almen J.,AVL MTC AB
SAE Technical Papers | Year: 2012
The present wording of implementing the regulation for type-approval of motor vehicles and engines with respect to emissions from heavy duty vehicles (e.g. Euro VI requirements) describes the procedure to determine gaseous emissions from on-road measurements using Portable Emissions Measurement Systems (PEMS). Emissions to be measured according to the PEMS protocol are carbon monoxide (CO), total hydrocarbons (HC) nitrogen oxides (NOx) and carbon dioxide (CO2). Measurement methods of particles will be included in the Euro VI requirements. Emission results from on-road testing can be used for In Service Conformity (ISC) pass/fail criteria but also for establishing emission factors for specific routes and verification of the fuel impact on the emissions. During on-board measurement, emission sampling, measurement of the exhaust parameters and recording of the engine parameters as well as ambient data shall continue throughout the normal in-use operation of the vehicle i.e. driving conditions that are mostly used by the operator or fleet owner of the particular vehicle type. During the past years a PEMS pilot study has been carried out in Sweden, supported by The Swedish Transport Agency, in order to verify the emissions from different types of heavy duty vehicles and fuels. This paper presents some of these results with focus on evaluating the impact on emissions measured with a PEMS instrument with regard to different alternative fuels such as Fatty-acid methyl ester (FAME), Dimethyl ether (DME), Ethanol and Compressed Natural Gas (CNG) when the vehicles are driven on the road during a normal working day. The results are compared with emissions from a diesel vehicle. Copyright © 2012 SAE International.
Almen J.,AVL MTC AB |
Erlandsson L.,AVL MTC AB
SAE Technical Papers | Year: 2011
The present wording on implementing regulation on type-approval of motor vehicles and engines with respect to emissions from heavy duty vehicles in Europe (e.g. Euro VI requirements) describes the procedure to determine gaseous emissions from on-road measurements using Portable Emissions Measurement Systems (PEMS). The gaseous emissions to be measured according to the PEMS protocol includes carbon monoxide (CO), total hydrocarbons (THC) and nitrogen oxides (NOx) for diesel engines and with the addition of methane (CH 4) for gas engines. Measurement methods of particles are at this stage under development (1, 2). Emission data from on-road testing can be used for calculation of In-service Conformity (IsC) pass/fail criteria but also for establishing local emission factors for specific routes. The procedure for the measurement is described in detail in the regulation (3). During on-board measurement, emission sampling, measurement of the exhaust parameters and recording of the engine parameters as well as ambient data shall continue throughout the normal in-use operation of the vehicle i.e. driving conditions should correspond to actual real life conditions. Certification testing of HD-engines is carried out in a very controlled laboratory environment by testing an engine as a stand alone unit. Results from real life emission testing might thus be very different from testing according to the certification procedure. This paper will present the impact on emissions from four heavy duty vehicles with regard to factors such as ambient temperature, engine coolant temperature as well as vehicle load. It will also highlight the variation in emission results with regard to various driving conditions using different calculation methods. Copyright © 2011 SAE International.
Adlercreutz L.,AVL MTC AB |
Cronhjort A.,KTH Royal Institute of Technology |
Andersen J.,AVL MTC AB |
Ogink R.,Volvo Car Corporation
SAE Technical Papers | Year: 2016
With alternative fuels having moved more into market in light of their reduction of emissions of CO2 and other air pollutants, the spark ignited internal combustion engine design has only been affected to small extent. The development of combustion engines running on natural gas or Biogas have been focused to maintain driveability on gasoline, creating a multi fuel platform which does not fully utilise the alternative fuels' potential. However, optimising these concepts on a fundamental level for gas operation shows a great potential to increase the level of utilisation and effectiveness of the engine and thereby meeting the emissions legislation. The project described in this paper has focused on optimising a combustion concept for CNG combustion on a single cylinder research engine. The ICE's efficiency at full load and the fuels characteristics, including its knock resistance, is of primary interest - together with part load performance and overall fuel consumption. In the process of increasing the efficiency of the engine the following areas have been of primary interest, increased compression ratio, thermal load at high cylinder pressure and the use of EGR to further increase efficiency. The overall goal in the project was to reduce the CO2-emissions while maintaining the performance and characteristics of the engine. The ambition is to reduce specific tail-pipe CO2-emissions in g/kWh by 50% compared to a modern gasoline engine. The goal was close to being reached at 45% reduction at full load and 25-34% on part load. This was done by theoretically downsizing the engine and increasing the specific performance of the engine. © Copyright 2016 SAE International.
Sandstroem-Dahl C.,AVL MTC AB |
Almen J.,AVL MTC AB
SAE Technical Papers | Year: 2012
In the EU regulations, specification's for diesel fuel quality is regulated in the standard EN590. Sweden has however for many years used an "Environmental Class 1" (EC1) diesel fuel. In addition to fulfilling the EN590 standard, the main difference today between the Swedish EC1 and the EN590 fuel specifications is that higher levels of aromatics and polyaromatics (PAH) are allowed in the EN590 standard. Aromatics are considered to be potentially mutagenic, and the higher levels of aromatics also lead to increased particle emissions. Earlier studies of the exhaust emissions from engines using the different fuel qualities have shown significant differences, both regarding regulated emissions and health effects. In these studies, vehicles from emission standard Euro III and older have been used. The scope of this study was to investigate whether the differences persist for a modern Euro V vehicle or not. Emission results from tests performed on a heavy duty vehicle fuelled with the two different diesel qualities are presented. The tests were carried out on a chassis dynamometer and the vehicle was driven according to the WHVC test cycle. Both regulated and several unregulated components were measured, along with CO2 and fuel consumption. The gaseous components were sampled in bags and measured second-by-second. Particulate matter was collected on filter and also measured second-by-second with a TEOM instrument. In addition to the particulate mass, the particle size distribution was measured with an ELPI instrument. The unregulated components includes olefins, PAH and aldehydes. Extract of the particulate and semivolatile phase was used to carry out the Ames' bio assay to analyze the level of mutagenicity in the exhausts. This study has shown that there were significant differences between these two fuel qualities for a modern Euro V vehicle. The emission tests performed with EN590 show higher levels of the regulated components NOx, PM and CO - all of which have shown direct and indirect effects on both health and environment. For the unregulated components, aldehydes are emitted to a greater extent when the vehicle is fuelled with the EN590 fuel. The higher levels of PAH in the EN590 fuel is reflected in the emissions, and the PAH extracts used for the Ames' bio assay show higher levels of mutagenicity for the EN590 fuel. The WHVC driving cycle can be divided into three subcycles, each representing different driving patterns (urban, rural and motorway). This enables an analysis of emissions relative to the driving pattern, and a comparison of the two fuels. Since HDVs are designed to operate on various conditions such as urban, rural and motorway, the exhausts from all of those conditions have been analyzed. NOx and PM emissions have especially been highlighted as problems in urban areas and the high levels are probably caused by diesel fuelled HDVs and LDVs. Previous studies of real driving emissions have shown that some Euro IV and V HDV emit as much as Euro III vehicles during urban driving. Copyright © 2012 SAE International.