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1
Content available Simulation tests of selected gas flow parameters through combustion engine valves
100%
Andrych-Zalewska M.
Combustion Engines
|
2020
|
tom R. 59, nr 4
21--28
EN
The article presents the numerical analysis of a single-cylinder gasoline engine with indirect injection and spark ignition. The goal is to recognize and analyze gas flow through inlet and outlet valves and channels. These data were obtained from the simulation of a four-cycle engine cycle without combustion of the fuel-air mixture. The simulation was carried out in ANSYS, using a dedicated IC Engine module. After the simulation, the result was analyzed on the cross-sectional plane of both the valves and the combustion chamber. This method provided the necessary and concise representation of the flow characteristics. Five separate stages are presented – two describing the different displacement of the valve for each inlet and exhaust stroke and one representing the phenomenon of overlapping. The type of flow, its speed and tendency to create turbulence are described.
2
Content available Analysis of exhaust emission processes during the Real Driving Emissions test
100%
Andrych-Zalewska M.
Archives of Transport
|
2023
|
tom Vol. 66, iss. 2
123--148
EN
The article deals with the study of exhaust emissions from a combustion engine in the Real Driving Emission (RDE) test. These tests are a simulation of real conditions of use of motor vehicles. Nowadays, RDE tests are mandatory for Light Duty Vehicle (LDV) and Heavy Duty Vehicle (HDV) vehicles and in the future, restrictive standard. Euro 7, which combines stricter limits with a comprehensive RDE test cycle, is becoming a challenge for current vehicle engineering. The paper presents the results of pollutant emission tests from a passenger car (PC). In the tests of LDV in the RDE test, the results of which are analyzed in the article, the Portable Emissions Measurement System (PEMS) mobile exhaust emission testing system was used. The processes describing the operating states of the vehicle and the combustion engine, as well as the processes of exhaust emission intensity and the intensity of the number of particulate (PN), were examined. The correlation between the considered processes was investigated. The emission of carbon monoxide, hydrocarbons, nitrogen oxides, particulate and carbon dioxide as well as the road PN were examined. The zero-dimensional statistical characteristics of the examined processes were also determined. The probability density and power spectral density of the processes were established. A great diversity was found in the properties of the process distributions, as well as in the dynamic properties of the processes. In the summary of the analysis of the results of the car speed process, the operating states of the combustion engine and the processes of exhaust emission intensity and the process of the intensity of PN in the RDE test, conclusions were formulated regarding, among others, course of the intensity of these compounds, correlation of the processes of pollution emission intensity and the intensity of the PN with the process of car speed, distribution of processes.
3
Content available Investigation of processes in the WLTC test of a passenger car with a diesel engine
100%
Andrych-Zalewska M.
Combustion Engines
|
2023
|
tom R. 62, nr 3
52--62
EN
The test results and their analysis was discussed in this article. The tests were carried out in accordance with the WLTP (Worldwide Light Duty Test Procedure), on a passenger car with a compression ignition engine. The analysis was conducted doe the following variables: vehicle speed, exhaust emission rate and fuel consumption volumetric rate. The subject of the research are exhaust emission components that are harmful to the health of living organisms: carbon monoxide, hydrocarbons and nitrogen oxides, as well as greenhouse gases. The research results have shown a very large range of values for carbon monoxide, organic compounds and nitrogen oxides emission rate characteristics. The average distance-specific emissions values of carbon monoxide, organic compounds and nitrogen oxides were very small and were in line with the Euro 6 requirements within a large margin. Correlation studies of the measured variables were conducted - between vehicle speed and exhaust emission rate as well as volumetric fuel consumption rates, and between exhaust emission rates and volumetric fuel consumption rates. The correlation studies have shown that the highest coefficient of determination in relation to vehicle speed was found for volumetric fuel consumption and carbon dioxide emission rate, and the weakest correlation for carbon monoxide emission rate and nitrogen oxides emission rate. The correlation between the rate of volumetric fuel consumption and carbon dioxide emission, as well as for hydrocarbon emission and methane emission rates, was found to be the strongest. The carbon monoxide emission rate was the least correlated with all the other measured variables. Dimensionless statistical characteristics of the measured variables were determined, such as: extreme values, range, mean value, median, standard deviation, kurtosis, skewness and coefficient of variation. For all of them, the mean value was much greater than the median, and the standard deviation was greater still, than both of those values. The numerical distributions for the values of exhaust emission rate and volumetric fuel consumption turned out to be leptokurtic and have right-sided asymmetry. The coefficient of variation analysis made it possible to assess that the most dynamic properties could be observed in organic compounds emission rate, followed by carbon monoxide and nitrogen oxides emission rates, and finally - the vehicle speed. Histograms of the examined processes were determined. The vehicle speed histogram was characterized by relative uniformity apart from the dominance of the idle speed. Histograms of exhaust emission rate variables were most frequently dominated by small values. The zero values occurred less frequently for the fuel consumption volumetric rate histogram. Based on the conducted research and the obtained data, a set of conclusions was drawn.
4
Content available Research of pollutant emissions from automotive internal combustion engines in conditions corresponding to the actual use of vehicles
100%
Andrych-Zalewska M.
Combustion Engines
|
2023
|
tom R. 62, nr 2
64--70
EN
The subject of the article is the study of pollutant emissions from automotive combustion engines that operate in conditions corresponding to the actual use of vehicles. Includes information on the properties of exhaust gas parameters characterizing the following features: energy, economic, environmental impact and serviceability, additional and constant. Reference was also made to the possibility of determining driving tests on the basis of the similarity of the frequency characteristics of the speed processes in both driving tests and in the real use of vehicles. The article presents the results of research on pollutant emissions from a passenger car during the RDE test. The emission of carbon monoxide, hydrocarbons, nitrogen oxides, particulate matter and carbon dioxide, as well as the number of particulate matter, were examined. The process of pollutant emission intensity and particle number intensity was presented. Tests were carried out on the statistical properties of the car speed, the intensity of pollutant emissions, and the intensity of the number of particulate matter. Correlation studies were carried out on the speed of the vehicle, the intensity of pollutant emissions, and the intensity of the number of particulate matter.
5
Content available Research on the results of the WLTP procedure for a passenger vehicle
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Eksploatacja i Niezawodność
|
2024
|
tom Vol. 26, no. 1
art. no. 176112
EN
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 emissionsand 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 mostsignificant 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.
6
Content available Investigation of exhaust emissions from the gasoline engine of a light duty vehicle in the Real Driving Emissions test
51%
Andrych-Zalewska M. , Chlopek Z. , Pielecha J. , Merkisz J.
Eksploatacja i Niezawodność
|
2023
|
tom Vol. 25, no. 2
art. no. 165880
EN
The article contains the research results and analysis of the processes that take place as part of a gasoline engine light duty vehicle Real Driving Emissions test. Dimensionless characteristics of exhaust emission and fuel mass consumption in the RDE test were also determined: emission intensity, particle number emission intensity, fuel mass consumption intensity. An algorithm for determining the characteristics specific distance pollutant emission, specific distance particle number and specific distance fuel mass consumption in the vehicle speed domain in the RDE test was presented using the Monte Carlo method. The determined characteristics were approximated by polynomial functions in the form of sets of points. These relationships were characterized by a large dispersion of values, which was primarily due to the fact that the random values of the averaging limits contain very different engine operating conditions.
7
Content available Exhaust emission from a vehicle engine operating in dynamic states and conditions corresponding to real driving
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Combustion Engines
|
2019
|
tom R. 58, nr 3
99--105
EN
The article presents the exhaust emission results from a diesel engine in dynamic states of engine operation in the driving tests: NEDC (New European Driving Cycle) and Malta test, developed at the Poznan University of Technology. The NEDC and Malta tests were carried out as simulations on the engine test bench mimicking the driving tests conditions. The test results of the emission of carbon monoxide, hydrocarbons and nitrogen oxides obtained in each of the tests were presented. The dynamic states have been classified depending on the time derivative value of the torque and engine rotational speed. Both the positive and negative as well as zero time derivative values of torque and rotational speed were considered. Therefore, overall six types of dynamic states were analyzed. A high sensitivity of exhaust emission to various types of dynamic states was found. The exhaust emission sensitivity to dynamic states in the Malta test was found to be higher than for the NEDC test, although these tests have similar properties (average rotational speed and average torque). This is due to the fact that the NEDC test is created on the basis of the similarity of zero-dimensional characteristics of the car's speed characteristic, whereas the Malta test was designed in accordance with the principle of faithful representation in the time domain of the NEDC speed curve.
8
Content available Influence of exhaust manifold modification on engine power
51%
Bober B. , Andrych-Zalewska M. , Boguś P.
Combustion Engines
|
2024
|
tom R. 63, nr 1
54--65
EN
The article deals with the subject of the impact of an exhaust system on the power of the internal combustion engine. In particular the article shows the possibility of increasing the power of the gasoline drive unit, interfering only with an exhaust system. The purpose of the tests carried out is to compare the results of measurements from the chassis dynamometer before and after the modification, and additionally to perform simulations for the key parts of the system in terms of shaping the power and torque curves. The analysis includes a simulation model of the exhaust gas flow through the serial manifold and also the sport manifold, especially the pressure distribution and the course of the velocity vectors at the characteristic points of the element. Before obtaining the final results of power measurements on the sport units, the roughness of the steel from which the collectors were made was also measured. The final stage is the measurement of power on the new exhaust system. The obtained results of power measurements and simulations were presented in the form of a summary, which focused on the impact of individual fluid mechanics phenomena on the formation of power and torque curves and detailed the advantage of the new exhaust system in comparison with the factory system in terms of increasing the performance of the tested vehicle.
9
Content available The influence of the heating time of a catalyst-covered glow plug on the exhaust emissions from a diesel engine
51%
Andrych-Zalewska M. , Merkisz J. , Pielecha J.
Combustion Engines
|
2021
|
tom R. 60, nr 1
52--56
EN
The paper discusses the application of an in-cylinder catalyst allowing a reduction of the exhaust emissions from a diesel engine. Its placement in the combustion chamber, the area where the process of combustion takes place, allows reducing the emissions (carbon monoxide, hydrocarbons, particulate matter) ‘at source’. The paper presents the possibilities of boosting the efficiency of catalysts in diesel engines by extending the time of heating of a glow plug (the catalyst applied on the glow plug). The tests were performed for the following conditions: no heating (marked 0+0), glow plug heating for 60 s after engine start (marked 0+60), glow plug heating prior to engine start for 60 s and glow plug heating for 60 s after engine cold start (marked 60+60). An improvement in the efficiency of oxidation of the exhaust components was observed as the glow plug heating time increased.
10
Content available Static internal combustion engine operating states in vehicle driving tests
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Combustion Engines
|
2019
|
tom R. 58, nr 2
50--54
EN
The article presents the compression-ignition engine test results of static operating states in driving tests: NEDC (New European Driving Cycle), RDE (Real Driving Emissions) and the Malta custom test cycle, developed at the Poznan University of Technology. The NEDC and Malta tests were carried out as drive cycle simulations on the engine test bench, the RDE test was carried out in the real driving conditions. The engine operating states are described by the physical quantities of speed and torque. For each of the tests, zero-dimensional characteristics of the values describing the engine operation states were determined, including: mean value and average standard deviation and coefficient of variation. Histograms of quantities describing the engine's operating states for considered tests and driving conditions were also determined. A large diversity of zero-dimensional characteristics of the quantities describing the engine's operating states for the considered driving tests and driving conditions was found.
11
Content available CFD analysis of the Ferrari 348 GTC intake system
51%
Andrych-Zalewska M. , Wielki Ł. , Ziora K.
|
2019
|
tom R. 20, nr 6
128--133
EN
The article presents CFD (Computational Fluid Dynamics) analysis of the intake system of a Ferrari 348 GTC sports car. With this system, an adequate amount of air is supplied relative to the current demand for fuel combustion. The air demand of a given engine was determined, then analyzes were carried out. The article contains an analysis of the velocity distribution: total velocities, angular velocities and static pressure distribution. In addition, local velocity and flow in the filtration chamber were determined along with the flow directions and returns as well as power lines. The cycle impact on the temperature, locations of the highest speed drop, increase in turbulence, the largest pressure differences, and modulus of elasticity were determined. This information allows to assess whether there are no unwanted phenomena occurring in the system, such as flow disturbances. The Ansys Fluent software was used for analysis.
PL
W artykule przedstawiono analizę CFD (Computational Fluid Dynamics) układu dolotowego samochodu sportowego Ferrari 348 GTC. W tym systemie dostarczana jest odpowiednia ilość powietrza w stosunku do bieżącego zapotrzebowania na spalanie paliwa. Określono zapotrzebowanie na powietrze dla danego silnika, a następnie przeprowadzono analizy. Artykuł zawiera analizę rozkładu prędkości: prędkości całkowite, prędkości kątowe i rozkład ciśnienia statycznego. Dodatkowo wyznaczono lokalną prędkość i przepływ w komorze filtracyjnej wraz z kierunkami przepływu i powrotami oraz liniami energetycznymi. Oceniono wpływ cyklu na temperaturę, lokalizację największego spadku prędkości, wzrost turbulencji, największe różnice ciśnień i moduł sprężystości. Informacje te pozwalają ocenić, czy w systemie nie występują niepożądane zjawiska, takie jak zakłócenia przepływu. Do analizy wykorzystano oprogramowanie Ansys Fluent.
12
Content available Determination of exhaust emission characteristics in the RDE test using the Monte Carlo method
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Archives of Transport
|
2023
|
tom Vol. 66, iss. 2
45--60
EN
The article presents a method of determining the characteristics of exhaust emissions and fuel mass consumption in real driving conditions based on a single test using the Monte Carlo method. The exhaust emission characteristics used are the relations between the emissions and the average vehicle speed, and the characteristic of the fuel mass consumption is the dependence of the fuel mass consumption at the average vehicle speed. The results of empirical research of a passenger car with a spark-ignition engine in the RDE test were used. The use of the Monte Carlo method made it possible to select the initial and final moments of averaging the process values, thanks to which it was possible to determine the discrete values of the characteristics for various values of average vehicle speeds. The determined discrete characteristics of the particulate mass and number emissions and fuel mass consumption relative to the average vehicle speed were approximated by polynomial functions of the second and third degree. The determined discrete characteristics, presented as sets of points, were characterized by a relatively small dispersion in relation to their polynomial approximations. The average relative deviation of the points of discrete characteristics from the value of the polynomial was in most cases small – less than 4%, only in the case of the number of particles emitted deviated from this, as the average relative deviation of the measured points from the determined polynomial was nearly 14%. Combined with the results of RDE empirical studies, the Monte Carlo method proved to be an effective method for determining the characteristics of exhaust emissions, measured in real vehicle operating conditions. The main advantage of the proposed method was a significant reduction in the actual workload necessary to carry out the empirical research – where it became possible to determine the characteristics in a large range of vehicle average speed values with just one drive test. Using standard methods of measuring this type of data, it would be necessary to conduct multiple tests, driving at different average vehicle speeds.
13
Content available Determination of characteristics of pollutant emission from a vehicle engine under traffic conditions in the engine test
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Combustion Engines
|
2022
|
tom R. 61, nr 4
58--65
EN
The paper describes the method of determination of exhaust emission characteristics from a vehicle engine based on the results obtained in a driving test simulated on an engine dynamometer. These characteristics are the relations between the specific distance emissions and the zero-dimensional characteristics of the process of vehicle velocity: the average velocity value and the average value of the absolute value of the product of vehicle velocity and acceleration. The exhaust emission characteristics are used to simulate the emissions from vehicles operating in different types of traffic conditions. The engine operating states in the engine dynamometer tests were determined by the operating conditions of the vehicle during the test. The authors applied the Monte Carlo method in order to determine the characteristics of different values of the zero-dimensional characteristics of the vehicle velocity process. This enabled the determination of the characteristics based on the test results from a single realization of the process of vehicle velocity. Additionally, the developed method allowed a replacement of the empirical research on the chassis dynamometer with the one performed on the engine dynamometer. The obtained exhaust emission characteristics are in line with the characteristics obtained on the chassis dynamometer in multiple tests.
14
Content available Influence of air velocity at inlet to the intake system on flow parameters
51%
Andrych-Zalewska M. , Ambroszko W. , Wielki Ł. , Ziora K.
|
2019
|
tom R. 20, nr 12
83--87
EN
The article presents CFD (Computational Fluid Dynamics) analysis of the Ferrari 348 sports car intake system for three variants of air intake speed to the system. The article contains an analysis of the distribution of velocities and static pressures. In addition, local velocity and flow in the filtration chamber were investigated. The influence of air velocity at inlet to the intake system on the abovementioned parameters was determined. The analysis is a prelude to the study of wave phenomena occurring in the intake system, affecting the fill factor of the cylinders. Ansys Fluent software was used for analysis.
PL
W artykule przedstawiono analizę CFD (obliczeniowej dynamiki płynów) układu dolotowego samochodów sportowych Ferrari 348 dla trzech wariantów prędkości wlotu powietrza do układu. Artykuł zawiera analizę rozkładu prędkości i nacisków statycznych. Ponadto zbadano lokalną prędkość i przepływ w komorze filtracyjnej. Określono wpływ prędkości powietrza na wlocie do układu dolotowego na wyżej wymienione parametry. Analiza jest wstępem do badania zjawisk falowych zachodzących w układzie dolotowym, wpływających na współczynnik wypełnienia cylindrów. Do analizy użyto oprogramowania Ansys Fluent.
15
Content available Fuel with a higher content of bio components in greenhouse effect aspects
51%
Andrych-Zalewska M. , Sitnik L. , Sroka Z. , Mihaylov V.
Combustion Engines
|
2023
|
tom R. 62, nr 1
36--42
EN
Transport is an energy-intensive sector of the economy and it is important where energy comes from and how it is used - now and in the future. The presented research results seem to encourage further work, despite the fact that the work had the character of basic research. The results were achieved in idealized conditions by the fact that the internal combustion engine was tested in static conditions on the test bench and the fuels contained components with strictly defined parameters. These conditions are different from everyday life. However, the obtained results seem to be valuable as they lead to conclusions regarding biofuels, and these conclusions are not directly formulated and published in the literature on the subject. The general conclusion from the research carried out is that the introduction of the so-called biofuels can contribute not to the reduction of CO2 emissions, but to its faster balancing in the environment. This balancing can be achieved but at the cost of increased fuel consumption. This increase in fuel consumption would probably not occur if the "bio" components in the fuel were synthetic hydrocarbons obtained from biomass. However, proving it requires wider studies, including LCA. Data for this LCA, especially about a fuel consumption, may be coming from long term operation of vehicles.
16
Content available Analysis of the operation states of internal combustion engine in the Real Driving Emissions test
51%
Andrych-Zalewska M. , Chłopek Z. , Merkisz J. , Pielecha J.
Archives of Transport
|
2022
|
tom Vol. 61, iss. 1
71--88
EN
Internal combustion engines represent the largest share of motor vehicle propulsion types. Despite the introduction of alternative drives (hybrid and electric), combustion engines will continue to be the main factor in the development of transport. Therefore, work related to their technological development and reduction of their harmful effects on human health and the environment is required. The development of internal combustion engines can be seen in two directions: technological changes resulting in increased efficiency of such engines and the second direction connected with limitation of exhaust gas emission. The present work is included in the second direction of research interests and concerns the analysis of various operating conditions of internal combustion engines. The operating states, both static and dynamic, determine the operational properties of internal combustion engines, such as fuel and energy consumption as well as pollutant emissions. Sofar, such operating conditions have only been mapped on a chassis dynamometer in various homologation tests. The course of the type approval test was known and the conditions of measurement were also known, which made it impossible to introduce a random factor into such tests. Currently, these properties are determined in tests performed in real vehicle operating conditions – RDE (Real Driving Emissions). Such tests are representing real operating conditions of motor vehicles. Limitations for performing tests in real traffic conditions are, apart from formal requirements concerning the duration and distance of individual parts, the dynamic conditions of vehicles determined by the speed and acceleration of the vehicle. The study analyzed the properties of vehicle speed processes and engine operating states in the RDE test, taking into account its individual phases – driving in urban, rural and motorway conditions. Engine operation states are the processes of the engine rotational speed and its relative torque. It was found that the dynamic properties of the vehicle speed process are much more significant than the engine operating states. It was also found that the road emission of pollutants in the RDE test, which is the property of vehicles measured in the test, the motorway phase properties have greatest impact.
17
Content available Analysis of the efficiency of the in-cylinder catalyst to reduce exhaust emissions during the cold start combustion engine
51%
Merkisz J. , Andrych-Zalewska M. , Pielecha J.
Combustion Engines
|
2019
|
tom R. 58, nr 3
38--45
EN
The article concerns the use of an in-cylinder catalyst that allows reducing the exhaust emissions during diesel engine operation. This is an additional method of exhaust emission reduction - however, the active component is placed inside the combustion chamber - hence much closest to the combustion process. This allows reducing the emissions at the very source (catalyst applied on the glow plugs). Such solutions are necessary because the reduction of exhaust emissions from vehicles is a key aspect of reducing the negative impact of transport on the environment.
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