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EN
In earlier designs, the compression-ignition engine units were controlled by means of mechanical elements. They were levers, rods, springs, pawls, cams and others. The quality of such control did not ensure the required repeatability of control parameters in the fuel injection and combustion process. After the introduction of the standards limiting engine emissions of the limited exhaust components, the aforementioned engine control systems were not able to meet the requirements. The mechanical regulation of mechanical systems has been replaced by electronic control systems. It was the development of computer techniques and software that enabled design solutions of control systems for injection and combustion process parameters in engines with sufficient accuracy and repeatability of test results. The modern EDC (Electronic Diesel Control) control system, due to the computing power of microprocessors increased in recent years, enables meeting high requirements of modern Common Rail injection systems. The article presents issues in the area of four thematic levels: the design and modernization of the engine, its operation, diagnostic problems in order to determine reasons of unit failures and bench-top methods for assessing the effectiveness of unit repairs as well as issues concerning alternative fuels.
EN
The purpose of the study was the research concerning the emissions of limited exhaust gas components of the AVL research engine equipped with Common Rail injection system, fuelled with different biodiesel blends and diesel fuel as reference. In details, the engine was powered with mixtures of rapeseed methyl esters (RME) with DF in the volumetric ratios of 10:90, 20:80, 30:70, 40:60 and 50:50. The tests were performed at: 1200, 1700 and 2200 rpm and the torque T = 5…35 Nm (step 5 Nm). The analysis of the obtained results showed that the emissions of hydrocarbons (HC) from the tested engine fuelled with biodiesel are lower than that of diesel fuel. Carbon monoxide (CO) emissions are also lower, except for low rotational speeds and low engine load T = 5…20 Nm. As for nitrogen oxides (NOx) emissions, it is also lower than that for the diesel fuel, except for high engine loads, in the range above 25 Nm, for each rotation speed of the engine load characteristics. Moreover, in this research it was confirmed that emission of particulate matter (PM) is also slightly reduced for the engine fuelled with tested blends.
EN
In the global fuel economy, new challenges concerning the use of alternative (vegetable) fuels in the internal combustion engines are starting to arise. The important issue is to meet the new limits on four main pollutant emissions from a diesel engines: CO (carbon monoxide), NOx (nitrogen oxides), HC (hydrocarbons) and PM (particulate matter). The design of a modern engine must be characterized by high efficiency, its dynamics of movement and durability. Dynamic development of plant fuels is forced by the new strategy of the global fight against the global warming. For these reasons, it is necessary to do research concerning the effects of the use of biofuels, including methyl esters, higher fatty acids of rapeseed oil for self- ignition engines. The current tests must concern the engines equipped with the latest Common Rail fuel injection systems. In the publication, the above-mentioned issues have been analyzed, and the results of tests of the basic injection process parameters have been presented. The AVL5402 engine was fueled with mixtures of diesel oil with RME ester of rapeseed oil produced by ORLEN Południe S.A. in Trzebinia. The impact of the fuel (v/v) RME content in the mixture with diesel oil on the injection process parameters such as: initial velocity of the injected fuel, critical speed of secondary fuel breakup, critical droplet diameter, microstructure of the fuel stream, droplet Sauter mean diameter, vertical angle of the fuel stream, have been justified. The impact of the fuel (v/v) RME content in the mixture with diesel oil on the above-mentioned parameters has been proved. During the tests, the engine worked on the load characteristics.
EN
The phenomena accompanying the self-ignition period have been the subject of extensive research in this area. They are usually carried out in constant volume pressure chambers or in reactors with constant air flow. Such tests are considered to be basic. The conditions in these tests are definitely different from those in compression ignition engines. Therefore, the comparison of the auto-ignition delay periods from test setups to those obtained from real engines raises a number of doubts. Because the self-ignition delay period determines the combustion process, a theoretical analysis was conducted, pertaining to a number of factors that have an impact on this process which determines the operational aspects of the engine, and thus its economics and ecology. The research object was a single-cylinder engine from AVL LIST GmbH in Graz, Austria. The engine is equipped with a Common Rail injection system. The test setup meets the following standards: Directive 1999/96/EC of the European Parliament and the Council of 13th December 1999, Regulation (EC) No 715/2007 of the European Parliament and the Council of 20th June 2007, as well as Commission Regulation (EC) No 692 /2008 of 18th July 2008. The analysis of the operational aspects of the self-ignition delay period was based on the results of tests on the AVL 5402 engine fueled with hydrocarbon fuels: diesel and synthetic oil. The engine was also fed with vegetable fuel – rapeseed oil. The obtained material from the tests warns the user of CI engines against the effects of their failure if the engine control parameters and the quality of fuel for its supply are not maintained as recommended by the manufacturers. The material contained in the publication is used for scientific analysis, and, which is worth emphasizing, is of a utilitarian nature.
PL
Przedstawiono wyniki badań obrazujące wpływ zawartości n-heksanu w mieszaninie z olejem rzepakowym na zwłokę samozapłonu tego paliwa w silniku o zapłonie samoczynnym. Zamieszczono wybrane właściwości fizykochemiczne oleju napędowego (ON) oraz testowanych mieszanin zawierających 10 oraz 15% obj. n-heksanu. Paliwa te wykorzystano do zasilania silnika badawczego zamontowanego w samochodzie marki Fiat Qubo. Przeprowadzone badania były kontynuacją badań wstępnych wykonanych na hamowni silnikowej, w których obiektem badań był silnik AD3.152 zasilany olejem rzepakowym z dodatkiem n-heksanu. Uzyskane wyniki potwierdziły, że obie testowane mieszaniny oleju rzepakowego z n-heksanem charakteryzowały się gorszą skłonnością do samozapłonu w stosunku do ON, co było związane bezpośrednio z ich odmiennymi właściwościami fizykochemicznymi.
EN
Mixts. of rapeseed oil with n-C6H14 (10 and 15% by vol.) were tested in diesel engine for applicability as motor fuels. The results were compared with data for gas oil. Self-ignition delay angle was higher than for gas oil and increased with increasing n-C6H14 content in the mixt. The kinetic combustion phase disappeared when the mixt. was used as the fuel.
EN
Despite the fact that more than a hundred years have passed since the first design of the compression ignition (CI) engine appeared, its optimal design has not yet been achieved. It is still the subject of constant modernisation in order to meet the new expectations of users in terms of its dynamics, economy, and, in recent months, also ecology. The most effective fulfillment of these requirements is achieved through new solutions of the fuel supply system and electronic control of injection and combustion processes. The publication includes the test results obtained on the basis of two engines. One of them is the single-cylinder CI engine AVL5402, and the other one – a threecylinder CI engine AD3.152. The first one is equipped with the Common Rail fuel supply system, electronically controlled with the selenoid injector. The second engine has a CAV distributor fuel injection pump and traditional, mechanical controlled injectors. The paper demonstrates how these two different structural systems for supplying and controlling engine parameters affect the selected indicators of the injection and combustion process. The influence of diesel fuel (DF) and rapeseed oil (RO) feeding the engine in both different injection and control systems on the unrepeatibility of the injection pressure on the maximum combustion pressures in the engine cylinder and, consequently, non-uniformity of the crankshaft rotational movement of the engine were also pointed out. The continuation of the research in this area seems to be expedient. They can be supplemented with statistical models of these phenomena. The results obtained in this way could be helpful in optimising the design of power supply systems and engine combustion chambers.
EN
A combustion engine turbocharger works in most difficult conditions due to high temperatures of the fuels it is driven by, vibrations and high rotational speeds of its shaft up to 200 thousand rpm. In addition, under these conditions, there are difficulties with lubrication of the blade axes. Thus, the combustion engine turbocharger is exposed to the damages occurring during the engine operation process. The frequency of damages was determined on the basis of tests for a selected group of vehicles. The object of detailed author’s own research was the Audi 3.0 V6 TDI engine of the Audi A6 C6 car which cooperated with a Borg Warner turbocharger with a variable angle of turbine steering wheel blades. These positioners are also exposed to adverse conditions: mainly vibrations and high temperatures. They are subjected to frequent damages, which often affect the engine control parameters. An analysis of the positioner element damage as well as a group of testers to assess their technical condition was made. The evaluated testers were allowed only to determine the efficiency of the turbocharger, but without indicating its technical condition or its positioner separately. Consequently, the author’s own research methodology and the construction of a new tester for the electromechanical turbocharger adjuster was developed. The necessary tests for the vehicle mileage up to 350,000 km were carried out. The self-designed tester can also estimate the degree of electromechanical wear of the positioner in the engine supercharging system as well as the resistance of its movements resulting from the pollution of the VTG turbocharger mechanism with the turbine steering wheel positioner, with variable geometrical parameters.
PL
Przedstawiono wyniki badań dotyczących wpływu wody zdyspergowanej w mikroemulsji paliwowej na zmianę okresu jej samozapłonu. Określono wybrane właściwości fizyczno-chemiczne oleju napędowego (ON) oraz testowanych mikroemulsji zawierających 4 lub 8% mas. wody destylowanej. Paliwa te wykorzystano do zasilenia silnika badawczego firmy AVL. Wyniki potwierdziły, że obydwie testowane mikroemulsje wodno-paliwowe charakteryzowały się mniejszą skłonnością do samozapłonu niż ON.
EN
Gas oil and its aq. microemulsions (4 and 8% by mass) were tested as fuel in diesel engine. Both tested microemulsions had lower ability for self-ignition than the gas oil. Selected phys.-chem. properties of tested fuels were detd.
PL
W artykule omówiony został wpływ dodatku biowęglowodorów na wybrane parametry spalania silnika o zapłonie samoczynnym. Badania wykazały, że syntetyczny olej napędowy może być wykorzystywany jako dodatek do mineralnego oleju napędowego. Proces spalania takich mieszanin zależy od ich składu. Użycie SYNON prowadzi do zwiększenia prędkości narastania ciśnienia w komorze spalania.
EN
The paper presents test results carried out with using of CI engine fuelled with diesel oil and synthetic fuels. Research results show that SYNON be used in diesel fuel. Combustion proces of such fuel blends depend on mixture composition. Using of SYNON in mixture with diesel oil follows to increase a value of maximium pressure rise in cumbustion chamber.
PL
W artykule przedstawiono diagnostyczną metodę pośredniego określenia luzów zaworowych w silnikach o zapłonie iskrowym za pomocą pomiarów napięcia samoindukcji obwodu pierwotnego cewki zapłonowej lub interpretacji mierzonego bezwzględnego ciśnienia powietrza w kolektorze dolotowym. Ta metoda umożliwia, po spełnieniu warunków koniecznych, określenie czy wymagana jest regulacja luzów zaworowych.
EN
This paper presents a diagnostic procedure for indirect determining valve clearance in spark-ignition engines by measuring the voltage of self-induction of the primary circuit of the ignition coil or interpret the measured absolute air pressure in manifold. This procedure determines, after fulfilling the necessary condi-tions, the need to adjust the valve clearance.
PL
W artykule przedstawiono analizę przyczyn uszkodzeń turbosprężarek samochodowych. Opisano i omówiono najczęściej występujące w eksploatacji uszkodzenia turbosprężarek. Bazowano na danych zebranych z praktyki reklamacyjnej i szkoleniowej wiodącej na rynku firmy zajmującej się regeneracją turbosprężarek.
EN
The article presents an analysis of the causes of damage to automotive turbochargers. Described and discussed the most common in use damage to the turbocharger. It was based on data collected from practice complaint and training market leading regenerator turbochargers.
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