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In order to better reflect the actual ecological performance of vehicles in traffic conditions, both the emission standards and the applied emission tests are being developed, for example by considering exhaust emissions for a cold engine start. This article presents the research results on the impact of ambient temperature during the cold start of a gasoline engine in road emission tests. The Real Driving Emissions (RDE) tests apply to passenger cars that meet the Euro 6 emissions norm and they are complementary to their type approval tests. A portable emissions measurement system was used to record the engine and vehicle operating parameters, as well as to measure the exhaust emissions during tests. This allowed for parameters such as engine load, engine speed and vehicle speed to be monitored. The cold start conditions for two different temperatures (8°C and 25°C) were compared in detail. Moreover, the engine operating parameters, exhaust concentration values and road emissions for the 300 s time interval, were compared. The summary of the article presents the share of a passenger car’s cold start phase for each exhaust compound in the urban part of the test and in the entire Real Driving Emissions test depending on the ambient temperature.

The article compares the exhaust emissions in road conditions of city buses: LNG and Diesel. Both buses met the Euro VI exhaust emission norm. The current strong drive to diversify fuels in Poland and the creation of a large gas port in Świnoujście for LNG imports creates an excellent opportunity to use this fuel, also in road transport. Therefore, the attempt to identify the emission in operation, in first place possible applications, i.e. an LNG bus, comparatively with the emission of a Diesel bus. The operational research carried out concerned such a bus and has not yet been carried out in the country, hence their innovation, also methodological. The conducted research, in particular, was aimed at verifying differences in exhaust emissions of carbon dioxide and nitrogen oxides. The study was carried out on one urban bus route performing trips on consecutive days in similar environmental conditions. The performed tests were not strictly type approval tests but only used for comparative purposes. Hence, it was necessary to determine the compliance factor for the relevant exhaust gas substances, with the use of an evaluation algorithm based on measurement windows. Based on these results, the assumption regarding compliance with the emission requirements for the tested buses was verified in real traffic conditions. The exhaust emission values (emission indicators) determined in this way did not exceed the permissible emission limit values for carbon monoxide, while for nitrogen oxides and non-methane hydrocarbons certain exceedances were found.

The process of fuel combustion in a diesel engine is determined by factors existing during liquid fuel injection and atomisation. The physicochemical properties of the fuel to a large extent decide upon the quality of this phase of cylinder fuelling. So it is important to ensure appropriate properties of a fuel affecting its atomisation and, as a result, combustion. The paper deals with the topic of diesel oil improvers and the analysis of their influence on atomisation and combustion indices. In the studies base diesel oil and a diesel fuel improved by a package of additives, were used. The process of conventional and improved fuel injection was analysed by using optical examinations. The amount of released heat was evaluated during the studies carried out on combustion. Significant aspects of the applied improvers in relation to fuel injection and its combustion have been indicated.

The paper presents the results of examination of particulate matter emission from the Diesel engine FPT 1.3 MJT simultaneously fuelled with diesel oil and natural gas CNG. The basic premise for engine adaptation was the addition of a small amount of CNG to reduce exhaust gas opacity and particulate matter emission. At this assumption, diesel oil remained the basic fuel, with contribution amounting to 0,70-0,85 of total energy delivered to the engine. The dual fuel engine was examined using an original controller installed in the Diesel engine FPT 1.3 MJT which controlled the diesel fuel dose. The dose of the injected natural gas was controlled by changing the opening time of gas injectors at constant pressure in the gas collector. The examined issues included the exhaust gas opacity, and the total number and fractional distribution of the emitted particles. The measurements were performed at twenty selected measuring points corresponding to the New European Driving Cycle (NEDC) test. The performed tests have demonstrated a positive effect of gas addition on exhaust gas opacity and particulate matter emission. Depending on test conditions, the exhaust gas opacity was reduced by 10÷92%, and the total number of particles by 30÷40%. The performed tests have revealed that a small addition of gas can reduce the load of the DPF filter, extend its lifetime, and increase engine reliability. Longer time intervals between successive DPF filter regenerations improve ecological properties of the engine.

The article discusses the use of an internal catalyst, which allows to reduce the emission of harmful compounds during internal combustion engine operation. This is a type of exhaust aftertreatment system; however, its placement inside the combustion chamber, and thus closest to the combustion process, allows reducing the pollution at the source (the catalyst was sprayed on the glow plugs). This is necessary because vehicle pollution reduction is a key aspect of reducing the negative environmental impact of transport. The presented research results are a part of a wider research scheme, on the evaluation of the internal catalyst impact in various engine operating conditions – starting from static tests (on an engine dynamometer), through dynamic dynamometer tests, and ending with vehicle road tests in real driving conditions. The use of an internal catalyst during dynamic tests results in a few percent reduction in the mass of carbon monoxide, hydrocarbons, carbon dioxide and the number of particulates in the considered measurement test. It is technically possible to introduce this kind of a technical solution in most vehicles with Diesel engines, thus resulting in improved ecological properties of internal combustion engines.

The article presents considerations regarding determining the NOx emissions from auxiliary compression-ignition marine engines. In order to determine the real impact of a given object on air pollution, it is necessary to first carry out research aimed at determining its emission characteristics. Thus, it is necessary to conduct tests in real operating conditions or to calculate the ecological indicators based on the operating conditions. The paper presents the NOx emissions intensity of an auxiliary Tier III standard marine engine, which is used in the drive system of various heavy, off-road vehicles and water vessels. Due to the structure characteristics of the considered engine group, the presented relations and results refer to only one cylinder. This data was used to calculate the NOx emission of a marine auxiliary engine, which used the operating conditions obtained from dynamometer tests and the engine construction (the number of cylinders). The presented methodology of activities can be used to assess the ecological indicators of ships in actual navigation, including primarily the maneuvers performed in the port. The article is supplemented with theoretical considerations regarding the problem of pollutant emissions from auxiliary marine engines.

Designing of modern transport systems involves the need to meet a large number of requirements. The influence of designed road infrastructure on the environment is very wide and important. The most valid aspect in this case is the reduction of emissions of harmful compounds by increasing the fluency of vehicles flow and building collision free road intersections. But it should be started from establishing the initial emission level of harmful compounds. This paper presents a methodology for determining exhaust emissions from vehicles moving on the national road no. 50 in area of Zyrardow. Modern measuring tools such as the PEMS and the microscopic road simulation software, using the application to determine exhaust emissions, were used for this purpose.

The article compares driving test data using the latest legislative proposals applicable to passenger cars. Several measurements were performed on the same test route in accordance with the RDE test guidelines, which requires a number of criteria to be met. These criteria include: the length of the measuring segments, their overall test time share, and the dynamic characteristics of the drive. A mobile device for reading the EOBD System information was used to record the engine and vehicle operating parameters during tests. This allowed for the monitoring of parameters such as: load value, engine speed and vehicle velocity. The obtained results were then analyzed for their compatibility with the RDE procedure requirements. Despite the same research route, the obtained results were not the same. The analysis also uses the two-dimensional operating time share characteristics expressed in vehicle velocity and acceleration co-ordinates. As a result it was possible to compare the dynamic properties, share of operating time and, consequently, to check the validity of conducted drive tests in terms of their practicability and emission values.

The introduction of new emission limits for exhaust emissions of ship engines contributes to the development of new powertrain solutions. New solutions in the simplest approach concern the reduction of the concentration of sulfur in motor fuels. Typically, the aforementioned fuels have a lower value of viscosity which causes a number of supply system problems. It is becoming more and more common to use fuel cells in engine rooms of various types of marine vessels. Unlike conventional systems that use internal combustion engines, these systems have zero exhaust emissions. Hydrogen, methanol, methane and other substances may be used as a fuel in fuel cells. However, so far the best operating parameters are manifested by cells powered by hydrogen, which is associated with difficulties in obtaining and storing this fuel. Therefore, the use of turbine engines allows the obtaining of large operating and environmental advantages. The paper presents a comparison of the ecological parameters of turbine and piston engines.

The article presents the results of studies conducted in the area adjacent to the airport located in Poznan, to determine the impact of aircraft landing operation on the concentration of particulate matter. Measurements were carried out using Engine Exhaust Particle Sizer Spectrometer 3090, enabling the measurement of the particle size distribution. The research allowed to determine the nature of the emitted particles and adds to the evaluation of impact on air quality. The tests were carried out during four aircraft landing operations. In each of the four cases total concentration of particulates number before landing (reference level) and during the landing of the aircraft was measured. In addition, the size distribution of reference level particles and its change after the landing operation was measured. Based on the conducted research, it was found that landing aircrafts have a significant impact on the concentration of particulate matter in the area adjacent to the airport. A single landing operation causes an substantially increase of the value of particle number concentration.

The article presents a study on emission measurements in passenger cars in tests conducted under real traffic conditions – Real Driving Emissions using a Portable Emission Measurement System type of equipment. A special feature of the outlined RDE tests is that they were performed in Polish road conditions, and thus their parameters may differ from their counterparts adopted in most European Union countries. Based on the findings vehicle emission conformity factors were developed, characterized as the fractional increase (or decrease) of traffic emissions during the homologation test or under normal operation conditions in relation to the emission limit standards (for chosen emission class) of the vehicle. Conducted research and the calculated conformity factors allowed for the environmental impact assessment of the vehicles of various emission classes, while also allowing early actions to restrict the emissions of selected components in passenger vehicles. The methods and measures used can also be applied to other types of vehicles (e.g. heavy duty or off-road vehicles) or vehicles powered by other fuels.

The article addresses the usage patterns of plug-in hybrid vehicles (PHEVs) under Polish conditions. The conventional approach to operating such vehicles assumes that they are used with a fully charged battery at the start. However, the economic circumstances of Polish users often do not allow for daily charging of vehicles from the domestic power grid. As a result, these vehicles are used not only in a mode powered solely by the internal combustion engine but also in a mode where the internal combustion engine is primarily utilized to charge the battery. An analysis was conducted on various ways of operating plug-in vehicles, evaluating not only harmful emissions but also fuel consumption (for battery states of charge: SOC = 100%, SOC = 50%, SOC = 0%, and SOC = 0 → 100%—forced charging mode). The study focused on the most characteristic vehicle segment in Poland, SUVs, and employed a methodology for determining exhaust emissions under real-world driving conditions. Results indicate that forced charging of such a vehicle's battery leads to over a 25-fold increase in carbon dioxide emissions (fuel consumption) in urban areas compared to operating the vehicle with a fully charged battery (CO—25× increase, NOx—12× increase, PN—11× increase). Operating a plug-in SUV without charging it from the power grid results in a 13-fold increase in fuel consumption compared to using the vehicle with a fully charged battery (CO—10× increase, NOx—6× increase, PN—4× increase). The emission results were used to evaluate Poland's charging infrastructure in the context of PHEV usage. The current state of the infrastructure and its development plans for 2030 and 2040 were analyzed. It was found that significant reductions in fuel consumption (by approximately 30%) and CO2 emissions are achievable by 2040. Emissions of CO, NOx, and PN are expected to decrease by about 10%, primarily due to the internal combustion engine operating at high load conditions in non-urban or highway scenarios. [ABSTRACT FROM AUTHOR]

In real road traffic, combustion engines of motor vehicles operate in dynamic conditions. Under such conditions, significant time variability in the values describing engine operations is observed, especially in terms of rotational speed and torque. Therefore, it is possible to model such conditions as probabilistic and to treat the properties of combustion engines in these conditions as stochastic processes. This paper presents a stochastic approach to the analysis of pollutant emission and fuel consumption test results of a motor vehicle driven in real traffic conditions. The empirical data were obtained from tests conducted on a car with a spark-ignition engine equipped with mobile on-board measuring equipment. The scope of the investigations covered the domains of time, frequency and process values. In the time domain, statistical characteristics of the processes were analyzed to explore potential correlations between them. In the frequency domain, the power spectral density of the processes was determined. In the process values domain, the emphasis was placed on examining the probability density of processes. A large diversification of the determined characteristics was found, in particular for vehicle velocity, engine operating states and the processes of pollutant emissions and fuel consumption. For practical reasons, the results of the correlation studies were particularly valuable, as they enabled assessment of the effects of taking action to reduce emissions of various pollutants. [ABSTRACT FROM AUTHOR]

The increasing number of vehicles operating in Poland, especially passenger vehicles, justifies the need to conduct air pollution emission tests in the context of the impact of vehicles on the natural environment. Firstly, this article reviews the publications related to air pollutant emissions and passenger vehicles traveling on Polish roads. However, it presents a special method using advanced research equipment to determine air pollutant emissions. The above research methods are justified in implementing clean transport zones. Real Driving Emissions represent an essential procedure in the implementation of clean transport zones in Poland, verifying the actual emissions of air pollutants and modeling this phenomenon using the results of real air pollutant emissions. The results of this research state that establishing a link between a vehicle's air pollutant emissions and its age can support making transport or delivery planning more sustainable and choosing less carbon-intensive means of transport to reduce the negative impact of transport on the environment. The scientific novelty of the proposed solutions is the verification of the actual emissions of Euro 6 vehicles and the modeling of air pollutant emissions as a function of speed and acceleration. The research results are included in this article and will become input data for further analysis in examining the impact of vehicle operating age on air pollution emissions. Consequently, the novelty of the present research also lies in its focus on the verification of the impact of operating age, particularly in the context of vehicles exceeding 15 years of age, on air pollutant emissions. By establishing a correlation between a vehicle's air pollutant emissions and its operating age, it becomes possible to make transport or delivery planning more sustainable. Furthermore, the selection of less carbon-intensive means of transport can contribute to reducing the negative impact of transport on the environment. [ABSTRACT FROM AUTHOR]

The article considers variables registered in the WLTP procedure. The test results of a passenger car with a compression-ignition engine have been analysed. The tests were carried out on a chassis dynamometer. The tests were performed for engine cold start and ran up to the point of reaching stabilized operating conditions. The average specific distance emissions and volumetric fuel consumption were assessed for individual test phases as well as for the entire test. It was found that the results in the first test phase, which corresponded to the engine cold start up to stabilized operating conditions, had the most significant impact on the overall exhaust emission and fuel consumption results in the test. The specific distance emissions of carbon monoxide, non-methane hydrocarbons and nitrogen oxides were by far the highest in the first phase of the test. In the fourth phase of the test, the specific distance emissions of methane and carbon dioxide turned out to be the highest, as well as the operational volumetric fuel consumption being the highest. [ABSTRACT FROM AUTHOR]