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The paper addresses the problem of toxic emission from non-road vehicles. The paper presents the results of the investigations and analyses related to the engine operating conditions of a selected group of non-road vehicles. The presented tests have been carried out on a large groups of vehicles - several from each representative group. This was chiefly on-site construction machinery (dump tracks, excavators, bulldozers) used in the construction of the motorway and as an auxiliary equipment in an open-cast mine. An analysis has been performed based on which a range of the most frequently used loads and engine speeds was determined. The obtained time density characteristics (distribution of speeds and loads in time) of the engines was compared to the measuring points of the toxic emission homologation cycle.

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 the test results relating to the influence of carbonate oxygenated additives to diesel fuel on exhaust emissions. Following the previous tests of glycol ethers (SAE Paper 2007-01-0069) and maleates (SAE Paper 2008-01-1813), the authors decided to use carbonates to obtain an even greater reduction in PM emissions. The significant effectiveness of carbonates on PM emission reduction was confirmed in tests performed by the authors. Diethyl carbonate was the most effective oxygenated compound with regard to PM emission reduction among all the 11 oxygenates which have been tested so far. Moreover, it is important to note that diethyl carbonate caused only a small increase in NOx emissions, thus it allowed for an essential improvement in the PM/NOx trade-off. A significant increase in the CO and HC emissions was, however, a negative effect of the use of carbonates.

The paper presents the test results of the influence of maleate oxygenated additives to diesel fuel on exhaust emissions. Following the previous tests of glycol ethers (SAE Paper 2007-01-0069), the authors decided to use maleates as oxygenates to obtain greater changes in PM/NOx trade-off than the changes obtained as a result of the use of glycol ethers. It was found that in the NEDC maleates at the same concentration as in the case of glycol ethers ensure more favourable changes of PM/NOx trade-off and, as a matter of fact, caused greater reduction in PM emissions without the growth of NOx emissions, however, at the cost of CO and HC emissions. The tests performed in the FTP-75 confirmed a significantly weaker influence of maleates, both positive (PM) and negative (CO, HC) than in the NEDC. They did not find in both cycles any influence of maleates at the tested concentration upon fuel consumption and CO2 emissions.

In the year 2005, the EURO IV fuel specification came into effect and the requirements for diesel fuel properties have become even more stringent. In this way, the potential of diesel fuel for emissions reduction has already been to a large extent exploited and the most emissions-sensitive fuel parameters can now be changed in a narrow range only. The shortfall in NOx and PM emissions control in diesel engines is, however, so great that more drastic fuel changes will be needed. One of the most promising fuel modifications for exhaust emissions control seems to be oxygenated additives. The objective of the study described in this paper was to analyze under transient conditions the influence of synthetic oxygenated fuel additives on exhaust emissions. The tests were conducted on a Euro IV passenger car. Six oxygenated additives were tested over the New European Driving Cycle (NEDC).

Research on the influence of oxygenated diesel fuels on the PM/NOx emission trade-off was carried out with use of 11 different synthetic oxygenated compounds, representing 3 chemical groups (glycol ethers, maleates, carbonates). Each of oxygenates were evaluated as a fuel additive at a concentration of 5% v/v in the same base diesel fuel. The tests were conducted on a passenger car equipped with a common rail turbocharged diesel engine over the European cycle NEDC and US FTP-75 cycle. All the tested oxygenates caused a reduction in PM emissions and most of them caused a certain increase in NOx emissions. The changes in emissions depended on the oxygenate type and cycle. In general, the favorable and unfavorable influence of oxygenated compounds was more intensive during the NEDC, which is a softer and less transient cycle than the FTP-75. The most favorable changes in the PM/NOx emission trade-off were obtained for maleates and carbonates.

Exhaust gas aftertreatment systems can, under certain conditions, create undesired chemical species as a result of their elimination reactions. A prime example of this is ammonia (NH3), which is not formed in the combustion reaction, but which can be formed within a three-way catalyst (TWC) when physicochemical conditions permit. The elimination of NOx in the TWC thus sometimes comes at the cost of significant emissions of NH3. Ammonia is a pollutant and a reactive nitrogen compound (RNC) and NH3 emissions should be analyzed in this context, alongside other RNC species. Examination of the literature on the subject published over the past two decades shows that ammonia, a species which is currently not subject to systematic emissions requirements for road vehicles in any market, is often identified as forming the majority of the RNC emissions under a range of operating conditions.

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 paper presents the results of tests on a combustion engine of an armored modular vehicle 8x8 Rosomak under combat simulating conditions. For the measurements of the toxic compounds a portable SEMTECH DS analyzer by SENSORS was used. The analyzer allowed a measurement of toxic compounds at the same time measuring the mass flow rate of the exhaust gases. The analysis of the PM emission was performed based on the measurement of the size of the particulate matter (analyzer 3090 EEPS - Engine Exhaust Particle Sizer™ Spectrometer - by TSI Incorporated) and counting of the particles (analyzer Particle Counter by AVL). The measurements of CO, HC, NOx, PM and fuel consumption were performed under the conditions of combat simulation and in the overboost mode. Based on the obtained results, an analysis of the engine and vehicle operation was performed and the on-road and unit exhaust emissions as well as on-road and unit fuel consumption were compared.

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 paper presents results of the road tests of exhaust gas emissions of vehicles of different emission classes (Euro 4 and Euro 5, with different mileage), fuelled with compressed natural gas. The tests of exhaust emissions were conducted on parts of the road with different characteristics of the traffic intensity. For each phase of the tests, the characteristics of the test run and the value of exhaust gas emissions were determined. To measure the exhaust emission the Portable Emission Measurement System (PEMS) was used.

European Union RDE (real driving emissions) legislation requires that new vehicles be subjected to emissions tests on public roads. Performing emissions testing outside a laboratory setting immediately raises the question of the impact of ambient conditions - especially temperature - on the results. In the spirit of RDE legislation, a wide range of ambient temperatures are permissible, with mathematical moderation (correction) of the results only permissible for ambient temperatures <0°C and >+30°C. Within the standard range of temperatures (0°C to +30°C), no correction for temperature is applied to emissions results and the applicable emissions limits have to be met. Given the well-known link between the thermal state of an engine and its emissions following cold start, ambient temperature can be of great importance in determining whether a vehicle meets emissions requirements during an RDE test.

This paper discusses the importance of the inclusion of emissions from the cold start event during legislative on-road tests on passenger cars (RDE - real driving emissions tests conducted under real-world driving conditions, as defined by EU legislation). Results from a recently-registered gasoline-powered vehicle are presented, with the main focus on the comparison of exhaust emission results: excluding/including the cold start during the initial phase of the RDE test. Cold start is the most challenging aspect of emissions control for vehicles with spark ignition engines and the inclusion of the cold start event in RDE test procedure has wide-ranging implications both for the testing process and compliance with RDE legislation via optimisation of aftertreatment systems and the engine calibration. In addition to some theoretical arguments, the results of an RDE-compliant test performed using the aforementioned procedures are presented.

One of the main issues in the development of diesel engines is the NOx emission while the chief cause for such emission is high nitrogen content in the air and high temperature of combustion. There is a variety of methods to reduce this particular emission. One of the most widespread is exhaust gas recirculation and one of the most recent is the application of Adblue additive into the exhaust gases as a reducing agent. There are also catalytic converters capable of reducing the said emission but their efficiency is as yet insufficient. One of the more daring related concepts is the elimination of nitrogen from the air supplied to the combustion chamber through the application of ceramic ionic conductors. The technology applied in the last method is a dynamically advancing trend in material engineering. The development in this field indicates that, soon, an oxygen generator useful in the automotive engineering will become a reality.

In order to measure the concentration of exhaust emissions a mobile emission testing analyzer SEMTECH DS by SENSORS Inc was used. In the study the results of the vehicle emission tests in the road conditions were presented, as this was the only way to obtain the information on real vehicle emissions. They include information on the emissivity of the vehicles in operation and deal with the real conditions of the vehicle in motion. Reliable measurement results were obtained which were verified in simulated conditions on a chassis test bed. The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the exhaust emissions. The dynamic engine properties were indirectly taken into account using all the speed range and the range of acceleration calculated for the city traffic in order to prepare a matrix of the emission intensity.

To stop the rapid automobile-related deterioration of the environment, a number of rigorous regulations and requirements have been introduced (e.g. on-board diagnostic system OBDII/EOBD). One of the most important functions of the OBDII system is a misfire detection. The misfire detection capacity is essential not only because it helps to control exhausts emissions, but also because it aids in preventing damage to the catalytic converter. The years to come will see increasingly stringent norms in general, in particular the locomotive diesel engines area also. This paper presents results of research on nonlinear analysis of vibro-acoustic signals obtained from a combustion engine (locomotive diesel engine and automobile engines) which pertain to misfire detection. The results of the analysis demonstrate the dominant Lyapunov exponents in the case with all the cylinders are in operation to be differing considerably from the condition with one cylinder disconnected.

The article is an investigation into the exhaust emission impact of operating a shunting locomotive SM42 and a track diagnostics machine UPS-80-001. The comparison of the two vehicles makes it possible to estimate the overall environmental costs of two different types of rail vehicles operating at their typical work parameters. This was done using selected exhaust emission indicators. It is used to indicate the need for further improvement in vehicle ecology such as hybrid or electric systems. Other solutions are investigated as forms of mitigating the ecological impact of operating such vehicles in or near human population centers.

This paper reviews the emissions from direct injection (DI) diesel engine in the initial period of controlled engine operation following start-up. The tests were undertaken in „cold start” mode (temperature of cooling water and lube oil equal to ambient temperature) and „warm start” mode* (after attaining a state of equilibrium). Both results were compared.

In order to measure the concentration of toxic compounds a mobile analyzer for toxic tests SEMTECH DS by SENSORS Inc. was used. In the study the results of the vehicle emission tests in the road conditions were presented as this was the only way to obtain the information on real vehicle emissions. They include information on the emissivity of the vehicles in operation and deal with the real conditions of the vehicle motion. Reliable measurement results were obtained which were verified in simulated conditions on a chassis test bed. The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the harmful compound emissions. The dynamic engine properties were indirectly taken into account using all the speed range and the range of acceleration calculated for the city traffic in order to prepare a matrix of emission intensity.