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The paper concerns the analysis of the combustion and exhaust emission phenomena in a direct gasoline dual injection system of a SI engine for various symmetrical injector placement parameters in the combustion chamber. Achieving a good combustion process is shaped by the direct fuel injection process, whose parameters vary. The novel direct injection system, which deploys two direct injectors mounted symmetrically, was subjected to this simulative research. This article focuses on the aspect of spatial and angular position of injectors in order to perform injection and achieve fuel combustion. The injector's pseudo-optimal location has been presented along with several changed positions (3 values of injector inset: 0, 1 and 2 mm, 3 values of injector distance from the cylinder axis: 16, 17, 18 mm and 3 values of angle between injector and the cylinder axis: 42.5, 45 and 47.5 degrees - 27 combinations altogether).

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 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.

Particles are one of the pollutants that affect air quality. The assessment of air pollution degree is conducted, among others, on the basis of parameters regarding the mass concentration of particles (PM2.5 and PM10). The growing awareness of the processes accompanying particles emissions is causing a growing interest in their other parameters such as number and diameter. Particles dimensions are important in determining their impact on human health. The most dangerous are particles of the smallest size; characteristic for internal combustion engines, mainly jet engines. The assessment of individual means of transport from the point of view of their ecological aspects is carried out in relation to fuel consumption, while in the case of particles; the analysis must be extended by their individual parameters. The article presents a comprehensive analysis of particles emissions from a jet engine during stationary tests.

The article describes issues related to the impact of transport means on the environment. These issues are currently very popular due to the increasing public awareness of the negative environmental and health effects associated with air pollution. The authors estimated specific emissions in passenger-kilometers, considering a domestic travel by air and road transport. The analyzed route is located between the Polish cities: Gdansk and Cracow. The selected route is long by domestic travel standards, but in that travel distance, the road transport is still competitive to the air transport. Selected means of transport belong to popular representatives in their classes. As a road vehicle, the authors selected a modern passenger car powered by a spark ignition engine, meeting the Euro 6 emission standard. Among the passenger aircrafts, an object which belongs small jet aircrafts, propelled with Rolls-Royce Tay 611C jet engines was selected.

Hydrogen Fuel-Cell (HFC) technology is popular in Asia (mainly Japan), the US (chiefly California) and Europe. HFC is mostly used in passenger cars and urban buses. HFC technology is also being introduced to railway transport. Hydrogen-powered trains are an attractive alternative to diesel trains, in particular on nonelectrified railways - where roughly 70% of the world’s 200 000 locomotives operate today - and in the markets of Europe and the US (together about 55 000 diesel locomotives today). Besides avoiding carbon emissions, hydrogen trains reduce noise and eliminate local emissions of NOX and particulates. Since they use significant amounts of hydrogen, the required infrastructure is limited and can be immediately utilised. Hydrogen-powered trains are already being introduced for light-rail vehicles and regional railways - such as the trams produced by the China South Rail Corporation.

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.

There is a growing appreciation for using buses powered by alternative fuels in urban transport. Considered as such are city bus with engines fuelled with LNG and hybrid bus. This article, as shown above, provides a comparison of road exhaust emissions from three city buses: one with a CI engine fuelled with diesel fuel, and the other with a SI engine fuelled with LNG and Hybrid bus. Both vehicles (CI and LNG) conformed to Euro VI emission standard (hybrid bus EEV), and the tests were carried out in real traffic conditions. Equivocal opinions about differences in emissions from those types of buses, among others - CO2 and NOx emissions, were the underlying cause of the tests. The comparative study was carried out along the same urban routes during bus trips over the following days in similar traffic conditions. Exhaust road emission was determined based on the vehicle's curb weight and route length, and operating fuel consumption.

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.

Non-plugin hybrids represent a technology with the capability to significantly reduce fuel consumption (FC), without any changes to refuelling infrastructure. The EU market share for this vehicle type in the passenger car segment was 3% in 2018 and this powertrain type remains of interest as an option to meet the European Union (EU) fleet average CO2 limits. EU legislative procedures require emissions limits to be met during the chassis dynamometer test and in the on-road real driving emissions (RDE) test, while official CO2/FC figures are quantified via the laboratory chassis dynamometer test only. This study employed both legislative test procedures and compared the results. Laboratory (chassis) dynamometer testing was conducted using the Worldwide Harmonised Light Vehicles Test Procedure (WLTP). On-road testing was carried out in accordance with RDE requirements, measuring the concentration of regulated gaseous emissions and the number of solid particles (PN).

Non-Road machines constitutes a large group of machines designed for various tasks and mainly using CI engines for propulsion. This category includes vehicles with drive systems of a maximum capacity of several kilowatts as well as with drives with a capacity of up to thousands of kilowatts depending on the purpose of the machine. Within this group, mobile machines referred to as NRMM (Non-Road Mobile Machinery) stand out. Numerous studies of scientific institutions in Europe and around the world have proven the differences between the exhaust emissions tested in type approval tests and the actual emissions in this group of vehicles. They result from differences in operating points (crankshaft speed and load) of engines during their operation. A big problem is also their considerable age and degree of wear. Approval standards themselves are less stringent than those of heavy-duty vehicles (HDVs), although the engines have similar design and performance.

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.

The article shows the results of particulate matter emissions obtained in the ESC cycle. In order to carry out the tests different devices were applied for the measurement of particular matter (AVL Smart Sampler - measurement by means of a gravimetric method of a partial exhaust smoke dilution, Horiba Mexa 1220 PM - measurement with the use of two flame ionizing detectors), which were then compared to the smokiness values (AVL 415 - measurement of exhaust smoke values, Opacimetr 439 - measurement of exhaust opacity). Having compared the obtained correlation results, main relationships of fractional composition of particular matter, obtained in the tests, were defined.

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.

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 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.

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.

In order to measure the concentration of exhaust a mobile analyzer SEMTECH DS by SENSORS Inc and particle matter by TSI 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 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 emission intensity.

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.

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.