Search Results

The benefits associated with the use of oxygen-containing diesel fuels in passenger cars are quite well described in the literature. This work describes the results of an 18-meter EEV city bus fueled with diesel fuel with the addition of 10% v/v of triethylene glycol dimethyl ether. This compound was chosen because it was effective in reducing exhaust emissions from light duty diesel vehicles. Emission tests (CO, HC, NOx and PM) of the city bus were performed over SORT (Standardized On-Road Tests) cycles using portable exhaust gas analyzers - PEMS. Significant differences in the emission of exhaust components were observed in individual SORT cycles. The level of road emissions reduced as the traffic smoothness increased, i.e. from the SORT 1 to SORT 3 cycle. The largest reduction in bus emissions associated with the use of the oxygenated additive (triethylene glycol dimethyl ether) applies to carbon monoxide and ranges from 50% for the SORT 3 cycle up to 90% for the SORT 1.

The share of hybrid and electric powertrains in the market increases continuously. In local driving conditions, electric vehicles are zero-emission, yet their regular use requires an infrastructure allowing the recharging of high-voltage batteries. Hybrid vehicles also allow the use of the electric drive; however, when the high-voltage battery is low, a combustion engine is used to recharge it. Hybrid powertrains do not require any changes in the infrastructure, nor do they force any changes in the driver's habits. The use of a hybrid vehicle may, however, reduce the operating time of the combustion engine, thus contributing to the reduction of fuel consumption. This reduction of fuel consumption results from a specifically selected energy flow strategy in hybrid systems. This strategy was the focus of the research performed to identify the energy flow conditions in a hybrid drive system under driving conditions corresponding to the RDE test.

The paper describes the measurement of PM emission from an excavator engine under actual operating conditions. The exploration of the relations between the engine operating parameters and its emissions requires measurements under actual conditions of engine operation. The specificity of the emission measurements, PM in particular, requires technologically advanced measuring devices. The situation gets even more complicated when, beside the PM mass. The particle size distribution and number (PN) also need to be measured. An important technical issue is the difficulty in fitting the measurement equipment in/on the vehicle in operation (e.g. excavator), which is why the presented investigations were carried out in a laboratory under simulated operation. The laboratory technicians applied load to the engines through the excavator hydraulic system.

The paper presents an analysis of the emission level from a heavy-duty truck of the GVW of 12,000 kg. The exhaust emission tests were performed under actual traffic conditions in the area of Poznań. For the tests portable exhaust emission analyzers SEMTECH DS and AVL Micro Soot Sensor were used. The characteristics of the exhaust emission components have been determined in relation to the engine speed and load as well as vehicle parameters (speed and acceleration). The paper includes an analysis of the engine operating conditions as well as the range of engine speeds and engine loads. The vehicle fuel consumption was also determined through the carbon balance method. Based on the obtained values of the emission of CO, NOx and PM, the emission indexes were determined that provided information on the relation of the measured emissions to the levels specified in the EEV standard. The emissions of all the exhaust components, except NOx were lower than the EEV limits.

The paper discusses the measurement of the PM emissions from non-road vehicles (a farm tractor and an excavator) under actual operating conditions. Full exploration of the relations between the operating parameters of these vehicles and their emissions requires measurements under actual conditions of their operation. The specificity of the emission measurements, PM in particular, requires technologically advanced measuring devices. The situation gets even more complicated if, beside the PM mass, we also wish to obtain the PM size distribution and particle number (PN). One of the more important technical issues is the difficulty in fitting of the measurement equipment in/on the vehicle in operation (e.g. a farm tractor). That is the reason why the investigations were carried out in a laboratory. The laboratory technicians applied load to the engines through external devices - a hydraulic system for the excavator and a brake coupled to the farm tractor power takeoff.

The tests related to the exhaust emissions from non-road vehicles are currently performed on a chassis dynamometer under the name of NRSC (ISO 8178) and NRTC. In light of the growing requirements related to the environment protection in transport the authors recommend determining the exhaust emissions through real vehicle operating conditions. The tests carried out under real operating conditions could be used for the process of optimization of future power trains of regular road vehicles and non-road vehicles. What is more, these tests should be taken into account in the works on the changes of the legislation related to the emission limits from combustion engines. The paper presents the results of the tests on the exhaust emissions from an agricultural harvester engine and a tractor engine in real operating conditions. The harvester operation during the test consisted in crops collection from the field and the tractor operation during the test consisted in plowing.

The investigations into the emissions from light-duty vehicles are carried out on a chassis dynamometer in the NEDC test in Europe and FTP75 test in the US. Such tests do not entirely reflect the real road conditions. It should be noted that the changes in the methodology of emissions testing should go in the direction where they get closer to the actual road conditions. The paper presents the road test results obtained in an urban congested areas. The analysis of the road tests results (exhaust emissions and fuel consumption) was carried out considering the road conditions (vehicle speed and acceleration). The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the exhaust emissions. For these measurements a portable SEMTECH DS analyzer by SENSORS, Particle Counter by AVL and Particle Seizer EEPS by TSI has been used.

The investigations into the emissions from light-duty vehicles have been carried out on a chassis dynamometer (NEDC test in Europe and FTP75 test in the US). Such tests do not entirely reflect the real road conditions and that is why we should analyze the correlation of the laboratory versus on-road test results. The paper presents the on-road test results obtained in an urban and extra urban cycles. For these measurements a portable SEMTECH DS analyzer by SENSORS has been used. The device is an analyzer enabling an on-line measurement of the emission gases concentration in a real driving cycle under real road conditions. The road tests were performed on road portions of several kilometers each. The obtained results were compared with the results obtained for the same vehicle during the NEDC test on a chassis dynamometer. The comparative analysis was performed including the urban and extra-urban cycles.

The aim of this work was a preliminary discernment of the possibility of application of Pd-Au-Ag-Ni-Co (non Pt) nanometric, powder alloy as an active part of a new PM filter. The hollow part structure of TiO2-x-RuO2-x has been proposed as the active layer on the catalyst support, composed of SiC. This structure is used in the catalyst technology. The washcoat of TiO2-x-RuO2-x has been obtained by the Flame Spray Pyrolysis Deposition method (FSPD). The influence of the preparation conditions such as: flow velocity, salt concentration, temperature and process atmosphere on the size and shape of TiO2-x-RuO2-x particles has been determined. The catalyst alloy contains nanoparticles of Pd-Au, which encapsulated the nanoparticles of Ag and Ni. Such prepared nano-particles containing noble metals or metals 4d (Ni, Co, Ag), show high tolerance to sulfur and good reversible properties. The atoms of Pd prefer five coordinated sites of Ti for adsorption.