21 research outputs found
Determining if Exhaust Emission From Light Duty Vehicle During Acceleration on The Basis of On-Road Measurements and Simulations
Vehicle exhaust emissions depend on multiple factors, such as the emission norm, driving parameters (speed, acceleration) or the technical condition of the vehicle. These driving parameters may often depend on the condition of the road infrastructure and other factors influencing road conditions. The article attempted to assess the emissivity during acceleration of a vehicle powered by a compression ignition engine. Mapping the actual values is possible with the use of exhaust emission measurement equipment that operates under the actual operating conditions of a vehicle. Recently, an increase in the use of simulation methods in research of this type has been observed. The authors decided to check the suitability of using road traffic simulation software to estimate the emissions during vehicle acceleration. The obtained results are promising, because in terms of the emissions of the analyzed exhaust gas component, the simulation results differed from the results obtained during measurements with the use of Portable Emissions Measurement System (PEMS) equipment by less than ±20%
Influence of the Particulate Filter Use in the Spark Ignition Engine Vehicle on the Exhaust Emission in Real Driving Emission Test
The introduction of new exhaust emissions norms for motor vehicles forces manufacturers to rely on th new technologies of exhaust gas aftertreatment and emission reduction. The past studies by the authors demonstrated a significant emission of nanoparticles from the gasoline engines with direct fuel injection, especially dangerous for the human health and life. The latest solution is a particulate filter designed for spark ignition engines, introduced in parallel with a norm limiting their number emission. The research conducted within the article concerned testing its effectiveness by measuring the vehicle equipped with and without the filter under real driving conditions. The drive cycle was made in accordance with the requirements of the RDE (Real Driving Emission) standard using PEMS (Portable Emissions Measurement System) equipment. The values of harmful gaseous components and solid particles were measured in terms of mass and number. The comparison of emission results indicated a significant efficiency of the filter in terms of particle weight and number reduction. The dimensional distribution of particle diameters were also analyzed, which changed as a result of the filter. The authors believe that the filter efficiency is the result of much higher temperatures of exhaust gases than in the case of diesel engines, which causes the incineration
Use of Toxicity Indexes in Reference to Carbon Dioxide for a Vehicle Equipped with a Two-Stroke Engine without an Exhaust Aftertreatment System
Research work on the new assessment of environmental indicators using equipment from the PEMS group (Portable Emission Measurement Systems) with motor vehicles is being developed. Due to the miniaturization of equipment, there are new measurement possibilities for more and more numerous groups of vehicles, including two-wheelers. The article presents the research and a summary of the results of a moped equipped with a two-stroke engine, approved in accordance with the Euro 3 standard. The research object is mainly used for driving in urban traffic. Therefore, the research route was created as the first communication frame in the Poznań agglomeration. In the analysis of the results, the author’s M toxicity index was proposed, which is based on the assumption that CO2 emission is a measure of the correctness of the combustion process. The equipment from the PEMS-AxionR/S+ group, characterized by small dimensions and low weight, was used to determine the actual motion parameters and the emission of toxic compounds. In the analysis of the measurement results, dimensionless indicators of toxicity M of gaseous compounds were determined and a comparative analysis was made with the values of other objects obtained in the course of previous research (motorcycle, passenger car, off-road vehicle, hybrid bus and agricultural tractor). Due to the engine design (two-stroke type), the worst environmental indicators were obtained for CO and HC compared to other tested vehicles
Integration of capacitors with carbon-lignin based electrodes in rail vehicles for enhanced energy efficiency
The article presents considerations regarding the possibility of recovering braking energy of a rail vehicle. The energy parameters obtained during acceleration and braking of the loaded railbus were taken as input data. It was found that over 13 kWh of energy was lost irretrievably in the braking resistors. Due to the speed of the discussed process, capacitors with an original design were proposed for energy recovery. For the purposes of this study, electrodes were fabricated using carbon derived from lignin carbonization at two distinct temperatures: 900°C and 1000°C. Based on the electrochemical tests carried out, it was found that the second proposed solution achieves a significantly better power-to-weight ratio – 13 kW/kg
Risk Assessment for Flight in Uncontrolled Airspace Under Visual Flight Rules
The paper attempts to assess the risk in the area of analysis which is the flight of general aviation (GA) aircraft carried out under Visual Flights Rules in the uncontrolled airspace. The flight, selected for further analysis, is a typical air operation performed in GA. The risk assessment was carried out in accordance with the risk management algorithm. The identification of hazard sources was made using a checklist of 123 questions about their occurrence. On this base a list of 37 threats identified in the presented area of analysis was obtained. The risk assessment was carried out by the MICE-RISK method. Among the defined threats, 16 threats fall into the accepted category, 15 threats are characterized by the tolerated category, and for 6 threats the category is defined as unaccepted. A dealing with risk methods were proposed. The re-evaluation indicated that the number of threats in particular categories are: 27, 6 and 6
Analysis of the Possibilities of Reduction of Exhaust Emissions from a Farm Tractor by Retrofitting Exhaust Aftertreatment
The paper evaluates particulate matter emissions and exhaust gas components from retrofitted engines of non-road vehicles measured under actual operating conditions. The content is divided into three main parts: formation of guidelines, production of the filter and emission tests. The obtained results clearly indicate excess PM and PN emissions from the engine under actual operating conditions when compared to the limits outlined in the type approval standards. Moreover, it was observed that the actual conditions are reflected to a very small extent at the points included in the stationary homologation test cycle. Based on these observations, the authors decided to modify the stationary test cycle. The measured exhaust gas compositions and their mass flow rates were used to create the geometry of the newly developed filter. The paper contains detailed results of the relative specific exhaust emissions of particulate matter and gaseous components at individual engine operating points. The exhaust emissions analysis made it possible to draw conclusions regarding the operation of the newly designed system. One of them is that fitting a metal-support particulate filter in the exhaust system significantly contributes to reducing the exhaust emissions
Analysis of the simulation results of various particulate filter configurations in exhaust system of a spark-ignition engine
W artykule przedstawiono wyniki symulacji przepływu gazów wylotowych przez trzy konfiguracje ceramicznego nośnika umieszczonego w układzie wylotowym silnika. Nośniki różniły się parametrami gęstości cel na całej długości filtra. Przebadano filtr o stałym parametrze CPSI (ang. Cell per Square Inch), filtr o dwóch różnych gęstościach cel oraz nośnik potrójny. Dla każdego z elementów filtra wprowadzone zostały warunki brzegowe, które określają charakter przepływu oraz definiują rodzaj powierzchni danego elementu. Określony został także skład gazów wylotowych, których przepływ jest symulowany. Warunki początkowe symulacji zawierają dane dotyczące ciśnienia, temperatury oraz prędkości przepływu. Do przeprowadzenia symulacji wykorzystano oprogramowanie AVL Fire Aftertreatment. Program stanowi wiodące narzędzie do symulacji CFD w dziedzinie silników spalinowych.The article presents the results of exhaust gas flow simulation by three configurations of a ceramic support placed in the engine exhaust system. The carriers differed in the cell density parameters along the entire length of the filter. A filter with a fixed CPSI (Cell per Square Inch) parameter, a filter with two different cell densities and a triple support were tested. For each element of the filter, boundary conditions have been introduced, which define the nature of the flow and define the type of surface of a given element. The composition of the exhaust gases whose flow is simulated was also determined. The initial conditions of the simulation include data on pressure, temperature and velocity. AVL Fire Aftertreatment was used to carry out the simulation. The program is a leading tool for CFD simulation in the field of internal combustion engines
Analysis of the simulation results of various particulate filter configurations in exhaust system of a spark-ignition engine
W artykule przedstawiono wyniki symulacji przepływu gazów wylotowych przez trzy konfiguracje ceramicznego nośnika umieszczonego w układzie wylotowym silnika. Nośniki różniły się parametrami gęstości cel na całej długości filtra. Przebadano filtr o stałym parametrze CPSI (ang. Cell per Square Inch), filtr o dwóch różnych gęstościach cel oraz nośnik potrójny. Dla każdego z elementów filtra wprowadzone zostały warunki brzegowe, które określają charakter przepływu oraz definiują rodzaj powierzchni danego elementu. Określony został także skład gazów wylotowych, których przepływ jest symulowany. Warunki początkowe symulacji zawierają dane dotyczące ciśnienia, temperatury oraz prędkości przepływu. Do przeprowadzenia symulacji wykorzystano oprogramowanie AVL Fire Aftertreatment. Program stanowi wiodące narzędzie do symulacji CFD w dziedzinie silników spalinowych.The article presents the results of exhaust gas flow simulation by three configurations of a ceramic support placed in the engine exhaust system. The carriers differed in the cell density parameters along the entire length of the filter. A filter with a fixed CPSI (Cell per Square Inch) parameter, a filter with two different cell densities and a triple support were tested. For each element of the filter, boundary conditions have been introduced, which define the nature of the flow and define the type of surface of a given element. The composition of the exhaust gases whose flow is simulated was also determined. The initial conditions of the simulation include data on pressure, temperature and velocity. AVL Fire Aftertreatment was used to carry out the simulation. The program is a leading tool for CFD simulation in the field of internal combustion engines
The impact of particulate filter substrate type on the gaseous exhaust components emission
The article presents ceramic and metal substrate filtration efficiency in the particulate filter of a spark-ignition engine with direct fuel injection. Gaseous exhaust components were taken into account. There are many publications on the solid particles mass and number reduction, so the authors examined the effect of catalytic carriers on gaseous compounds, such as CO, NOx, THC, whose content also poses a threat to human health and life, and this issue is not often described in the literature dedicated to measurements of modern internal combustion engines. During the tests, the length and carrier material effect on the emission of harmful substances in exhaust gases was determined
Harmful exhaust components and particles mass and number emission during the actual drive of a passenger car in accordance with the RDE procedure
The article presents toxic exhaust components emission measurement results as well as solid particles mass and number. The test involved a direct gasoline injection engine, in which special attention should be paid to the particulates number emission. Small diameters of nanoparticles make them particularly dangerous to human health. Nowadays, vehicle engines are constantly improved and modernized as a result of the need to meet existing exhaust gas emission standards. One of the few ways to determine the actual content of toxic and harmful compounds in the exhaust gases is the RDE (Real Driving Emissions) procedure, the requirements of which apply from 2016 for new vehicles, and from 2019 will apply to all registered passenger cars. The RDE procedure does not replace the WLTP (World Light-Duty Vehicle Test Procedure), but complements it. The tests on the dynamometer are separated from external conditions such as traffic volume or congestion and are not a sufficient indicator of emissions in real traffic conditions