Wyniki wyszukiwania - Biblioteka Nauki

1

Zastosowanie techniki jądrowej do badań silników spalinowych

100%

Rawski F.

Zeszyty Instytutu Pojazdów / Politechnika Warszawska

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2003

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tom z. 4/51

31--39

PL

W artykule przedstawiono problemy związane z transportem powietrza oraz paliwa przez układ dolotowy silników ZI. Metoda badań związana z transportem paliwa odnosi się do silników ZI. Jej oryginalnością jest zastosowanie w badaniach techniki jądrowej.

EN

This paper thesis the problem connected with transportation fuel the piston engine, speciality of the fuel micsture. the originality investigation this method is the isotope technology.

2

Measurement of mechanical losses in the combustion engines

100%

Drab O. , Voženilek R. , Beroun S.

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tom Vol. 17, No. 3

63-67

EN

The development of a new combustion engines is connected with endeavour for escalation of the total efficiency. Escalation of the total efficiency can be: minimization of the mechanical losses in the combustion engines or minimization of the unsuitable equipment capacity of accessories. Now research and development programs of a manufacturer of the combustion engines search effectual equipment and method for this escalation of the total efficiency. The escalation of the total efficiency is important for a minimization fuel consumption and consequently for lower emissions. Turn of the combustion engines is used method for measurement of mechanical losses very often. The paper will show choice of the measurement results on the testing bench. The Technical University of Liberec, Department of Vehicles and Engines, has developed a design of a testing bench which would enable the measuring mechanical losses of the combustion engines for different temperatures of cooling water and engine lubrication oil. Each medium (lubrication oil and cooling water) have own circle with automatic temperature regulation. The testing bench has automatic system for change revolution and automatic system for measurement: torque, revolution, temperatures and pressures. The asynchronous motor (company SIEI, type MA 133 K - 62 with power 28 kWI 6000 l/min) is used for drive of combustion engine in the testing bench.

3

Określenie zmian momentu tarcia w cyklu pracy silnika spalinowego

100%

Iskra A.

Czasopismo Techniczne. Mechanika

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2004

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tom R. 101, z. 6-M/1

279--286

PL

Silnik spalinowy napędzający samochód pracuje z mocą stanowiącą średnio poniżej 50% jego mocy znamionowej. W takich warunkach sprawność ogólna silnika w znacznym stopniu zależy od sprawności mechanicznej. Sprawność ta uwarunkowana jest rozkładem strat tarcia w poszczególnych fazach cyklu roboczego [1]. Istnieje zatem potrzeba dokonywania pomiaru chwilowego momentu koniecznego do obracania wałem silnika. Pomiar momentu chwilowego, w przeciwieństwie do momentu średniego, nie jest zadaniem prostym. Na moment obrotowy nakłada się moment wynikający z drgań własnych układu silnik spalinowy - maszyna elektryczna, co zniekształca rzeczywisty moment napędu silnika. W referacie zaproponowano sposób eliminacji z sygnału momentu zakłóceń spowodowanych drganiami własnymi.

EN

The car combustion engine usually works with the power below 50% its nominal value. In such conditions the total efficiency of the engine essentially depends of the mechanical efficiency. This kind of efficiency is conditioned on friction losses in all phases of the working cycle [1]. There are measurement methods of the instantaneous necessary moment to turn the motor crankshaft. The measurement of the instantaneous moment, as opposed to the average moment, is not a simple task. The consequential torque is overlapped by resonance oscillations of the system: combustion engine - the electric machine. This physical phenomenon falsifies the real moment of the engine drive. In the paper the author proposes the elimination method of resonance oscillations from the measured torque signal.

4

Numeric calculation roll up process of piston's ring from steel tape

100%

Kaźmierczak A. , Szynalski K. , Zabłocki W.

Journal of KONES

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2006

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tom Vol. 13, No. 4

279-287

EN

In article shortened description of technology was introduced roll up of steel rings of pistons' combustions' engines and used of this process numeric model to calculation of deformations and loads in tape. This technology makes possible the elimination of casting with process of production of piston rings. View of device to rolling up from steel tape the rings, views of seat of 6 rolls of steel tape as well the working unit rolling up the tapes of device to rolling up the rings, scheme of team formative, formative rolls, steel chromic sealing piston ring, the material characteristics of tape, geometrical model of arrangement of roll rolling up - the tape: a) scheme of whole model, b) the fragment of model of arrangement rolling up, discreet model of arrangement of roll rolling up - the tape, function of burden, tensions in elements of tape, tensions in elements of ring, discreet model of ring to calculations under static load are presented in the paper too.

5

Problems with determination of rotation speed fluctuations at the combustion engine work cycle

100%

Iskra A.

Journal of KONES

|

2005

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tom Vol. 12, No. 1-2

103-110

EN

The coefficient of speed fluctuations delta is the one of engine basic operational parameters defining its utilitarian advantages. Such defined this simplest parameter determines the discrepancies from the rotational speed constant within an engine individual cycle. However, the principle of engine run causes the unavoidable fluctuation of engine instantaneous speed. This phenomenon can be utilized as a diagnostic signal. The way of determination of crankshaft instantaneous speed could be the answer to this problem. Determination of engine rotational speed instantaneous value is carried out according to three methods presented below from the less to the most accurate: on the basis of engine torque calculation and eventual computation of velocity omega, on the basis of engine torque measurement and eventual computation of velocity ?, on the basis of measurement of time intervals between consecutive signals generated by the encoder. This is the subject of the following paper.

6

Acoustic Diagnostics Applications in the Study of Technical Condition of Combustion Engine

100%

Deptuła A. , Kunderman D. , Osiński P. , Radziwanowska U. , Włostowski R.

Archives of Acoustics

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2016

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tom Vol. 41, No. 2

345--350

EN

The paper presents the possible applications of using acoustic diagnostics in inspecting the technical condition of an internal combustion engine with autoignition on the example of the Fiat drive unit with common rail system. As a result of measuring the sound pressure level for specific faults and comparing the noise generated by the motor running smoothly, the detailed maps of changes in the acoustic spectrum are possible to generate. These results may be helpful in the future diagnostics of internal combustion engines. In the paper, the results of scientific work in the area of research, design and operation of internal combustion engines, conducted at the Department of Automotive Engineering, in cooperation with the Laboratory of Hydraulic Drives & Vibroacoustics of Machines at the Wroclaw University of Technology are included.

7

Probability measures of likelihood of diagnosis of the technical state of main combustion engines of sea-going ships

80%

Girtler J.

Journal of KONES

|

2009

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tom Vol. 16, No. 2

125-132

EN

The paper presents reasons for the need of discerning the notions: likelihood of diagnosis and rightness of diagnosis while taking operating decisions. A probability formula for establishing the right diagnosis has been derived as a likelihood measure of diagnosis. For deriving the formuła, the theory of semi-Markov processes and Bayes' formula of the conditional probability have been applied. Other probability measures of likelihood of diagnosis have been also presented. These measures concern the technical state of such important systems as combustion engines of sea-going ships. However, they can be of use also for other ship systems. The paper provides description of a stochastic decision situation following from operation of combustion engines in any operating system and on this background there is presented some proposals of applying the technical diagnostics for controlling the engine operating process. Formulating a problem for the combustion engines, solving the problem, diagnostic inference and likelihood of diagnosis as well a simplified model of combustion engine operation taking into account diagnosis and control in time of operation are presented in the paper.

8

Układy tribologiczne w systemach funkcjonalnych silnika spalinowego

80%

Sroka Z. J.

Problemy Maszyn Roboczych

|

2003

|

tom Z. 22

85-96

PL

Spośród wielu czynników decydujących o sprawności silnika spalinowego, procesy tribologiczne w nim zachodzące mają znaczący udział. Poprawne zdefiniowanie procesów zużywania, tarcia i smarowania daje możliwość właściwego planowania i nadzorowania eksploatacji, jak również definiowania trwałości poszczególnych systemów funkcjonalnych silnika. Zdefiniowanie układów tribologicznych w silniku i przedstawienie przykładów było podstawą realizacji niniejszego projektu. Na bazie systemów konstrukcyjnych i funkcjonalnych silnika spalinowego utworzono układy tribologiczne silnika.

EN

Internal combustion engine was described as a technical system consists of several levels of constructional and functional subsystems. Hierarchy of level depends on given problem which can be discussed. Tribological systems inside of engine were defined. There were types of friction and wear included. This project is a entry point to build tribological models needed both for effective management of reliability of combustion engine and prediction of its durability.

9

Some selected examples of fem modelling of structure-affecting material and manufacturing faults

80%

Jachimowicz J. , Małachowski J. , Krasoń W. , Kajka R.

Journal of KONES

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2008

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tom Vol. 15, No. 1

97-107

EN

In design practice, in most of cases, stresses and deformations of structures with nominal dimensions and average material properties were analyzed. It have been concluded that such procedure is most often sufficient. However, there are design solutions, especially in high-effort structures for example aircraft and turbine engines, where scatter of geometrical dimensions consistent with assumed tolerances cause significant scatter of stresses and strains, differ from values coming from nominal dimensions. Scatter of these values have essential influence on service life of presented structures. Example of such effect is described in the paper. There were used FEM analyses to determination of scatter of stresses and stres s concentration coefficient in herringbone lock joint of K-15 engine's turbine. Another example of fault impact on stresses in structure is analysis of undercarriage element with material fault. Both these examples indicate on great sensitivity of stress distribution on manufacturing imperfections. The impact of these faults and imperfections reaches hundreds of per cent, and in some cases could be serious menace of operating safety. In structures with the multiple 3D stress state, non-linear geometric and material phenomena, with contact between friction-affected elements, any geometric imperfections can cause considerable local changes in the stress and strain.

10

The control of valve timing with magnetoelectric actuators

80%

Siczek K. , Kuchar M.

Journal of KONES

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2009

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tom Vol. 16, No. 3

357-365

EN

The new control algorithm for the valve timing in camless combustion engine is presented in the article. The magnetoelectric actuators have been used in the valve timing for analyzed popular combustion engine. Each titanium valve has been connected with the coil of actuator. Such coil can move in the magnetic field, generated in magnet circuit containing sintered Nd-Fe-B magnets, the core, pole shoes and air gaps. The movement of coil can occur when current flows in the coil winds and then electrodynamic force is generated. The nonlinear curves of generated electrodynamic force versus displacement of coil - valve assembly and vs. current in the coil have been computed using FEM method and presented in the article. The new mathematical model has been elaborated to calculate valve lift vs. coil lift for different coil currents and dynamic parameters of the coil. The values of current in coil should be controlled by the elaborated algorithm with the feedback. This algorithm has been based on tracing of position points of valve, during valve movement. The modelled course of valve lift vs. time has been first elaborated, for the needed rpm of engine. Next the first approximated current pulse train has been generated, the movement of the coil - valve assembly could be obtained. The calculated position of valve has been compared with the valve position from modelled course of valve lift vs. time. Basing on obtained difference of valve lift, the next current pulse train has been corrected in such a way, to obtain in any moment the closest position of valve to the one from modelled course. The obtained courses of valve lift vs. time for different modelled courses of valve lift vs. time and vs. rpm of engine have been presented in the article.

11

Module engine operating on example of Pratt&Whitney F100-PW-229

80%

Usarek W.

Silniki Spalinowe

|

2011

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tom R. 50, nr 4

14-21

EN

The article presents operation of Pratt&Whitney jet engine F100-PW-229 used in F-16 planes used by Polish Air Forces. The description bases on general construction of the engine and focuses on its modularity. Besides, there has been described the rules of operation of F100-PW-229 engines. The article concentrates also on specifics of maintenance and repairs of module engines and competence of flight squadrons for performing such repairs.

PL

W artykule przedstawiono charakterystykę odrzutowego silnika F100-PW-229, firmy Pratt&Whitney, stosowanego w samolotach F-16, będących w posiadaniu Polskich Sił Powietrznych. Opisano ogólną budowę tego silnika, zwracając szczególną uwagę na jej modułowość. Przedstawiono zasady eksploatacji silników F100-PW-229 obowiązujące w jednostkach Polskich Sił Powietrznych. Opisano specyfikę prac obsługowo-naprawczych silników o budowie modułowej oraz kompetencje jednostek organizacyjnych eskadr lotniczych do prowadzenia prac w tym zakresie.

12

An effect of physical and chemical properties of commercial diesel fuels on engine parameters

80%

Sroka Z. J. , Reksa M. , Kułażyński M.

Journal of KONES

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2007

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tom Vol. 14, No. 4

447-452

EN

This paper is focused on problem of quality of diesel commercial fuels in Polish market and an effect of their properties as well on engine parameters as environment The academic staff from Wrocław University of Technology put the own experience to the huge discussion by making research in the Wroclaw-city, where some probes of fuels were taken from six different commercial fuel stations. Chemical and physical properties of fuels were checked. A real diesel engine VW 1,9 TDI was investigated in university lab of Division of Motor Vehicles and Internal Combustion Engines. Typical engine performances were built including power, torque, fuel consumption, toxicity levels due to different fuels. The IC engine on the test bench, oxygen content in fuels, example of full load performance of VW1,9 TDI for fuel Bio D20-type, differences of mean effective pressure for different fuels, differences of carbon monoxide in exhaust for different fuels, differences of nitric oxides in exhaust for different fuels, differences of smog level in exhaust for different fuels, differences of heat release for different fuels, relation between engine torque and oxygen content in fuels vs. engine rotation are presented in the paper.

13

The use of laser equipment to optimize the operating parameters of the fuel injector of combustion engine

80%

Kowalski M. , Jankowski A.

Journal of KONES

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2018

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tom Vol. 25, No. 4

199--206

EN

The conducted tests were aimed at determination of the drop diameters and shaping of the velocity field at different configurations of the test injector. The test results allowed defining the relationship between the injector configuration and the distribution of velocities and dimensions of drops in the fuel stream. The effect of the fuel viscosity and injection pressure on the dimensions of fuel drop diameters and the distribution of the velocity field of drops in the stream were tested. The tests were carried out on a special test rig with a fixed volume chamber. The measurements were carried out with the use of laser Doppler measurement systems (PDPA, LDV). The tests were conducted for seven different fuel types varying in viscosity and surface tension. In addition, the injection pressure from 50 MPa to 130 MPa was applied. The test results allowed determining the relationship between the injector structure configuration, fuel types and fuel additives, and the distribution of velocity and an atomisation spectrum of drops in the fuel stream, and the air impact on the fuel stream.

14

The lean mixture combustion of simulated producer gas in SI engine

80%

Przybyła G. , Szlęk A. , Ziółkowski Ł.

|

2013

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tom Vol. 20, No. 3

331--338

EN

In this paper the experimental results of spark ignited (SI) engine fuelled with lean mixture of simulated producer gas compared with chosen gaseous fuels are presented. The SI engine test fuelled with simulated producer gas, natural gas and simulated biogas with variable value of excess air ratio has been done. The experiments were carried out on the petrol engine with a low engine displacement. Typical SI engine was selected in order to evaluate the potential application of gaseous fuel (i.e. producer gas, natural gas or biogas). These types of engines are available on a wide scale and commonly used in automotive sector because of the low purchase price and operating costs. It is expected that after minor modifications, the engine can easily operate in micro CHP system. The main goal of this work is to determine the performance of the engine and its impact on the environment during the combustion of the lean producer gas mixtures. The study shows the impact of both the excess air ratio and the type of fuel used for engine performance and emission index. Combustion of lean mixtures of producer gas leads to an increase of carbon monoxide in the exhaust. Increasing the value of excess air ratio affects the growth of indicated efficiency of the engine

15

Wybrane kierunki działań tribologii w silniku spalinowym.

80%

Kaźmierczak A.

Zagadnienia Eksploatacji Maszyn

|

2000

|

tom Vol. 35, nr 3

93-107

PL

W opracowaniu przedstawiono wybrane kierunki działań tribologii w silnikach spalinowych. Punktem wyjścia do ich określenia jest analiza sprawności silnika spalinowego. Drogą poprawy sprawności mechanicznej jest komponowanie nowych materiałów, które współpracują w obecności olei smarujących o stabilnych własnościach temperaturowych. Autor pracy opracował uszczelniający pierścień tłokowy, którego boczna powierzchnia jest pokryta powłoką z azotku tytanu. Współpraca tak powstałego pierścienia z tuleją cylindrową pozwala wydatnie obniżyć straty tarcia w węźle pierścień tłokowy-tuleja cylindrowa-tłok. Nowe materiały muszą pracować w obecności nowych olei smarujących, przejmujących w znacznym stopniu funkcję chłodzącą. To kolejny z kierunków prac tribologii w silniku spalinowym i jednocześnie możliwość podniesienia jego sprawności. W opracowaniu przedstawiono, oprócz możliwych do realizacji zmian w układzie korbowym silnika, również zmiany w układach zasilania zarówno silników o zapłonie samoczynnym, jak i silników o zapłonie iskrowym.

EN

In the papers presented are selected activity directions (activities) of tribology of combustion engines. Starting point to specify them is analysis of the combustion engine's efficiency. Engine's efficiency depends on of assumed thermal cycle (Otto, Diesel, Sabathe), real behavior of the combustion process and mechanical efficiency. Based on current knowledge the efficiency of a combustion engine can reach approx. 0,55 but assuming mechanical efficiency equals to 1. The way to enhance mechanical efficiency is composing new materials, which work in presence of oils of stable temperature properties. The author has developed the piston ring which face is covered with Titanium Nitrid layer. Cooperation of such ring with the cylinder sleeve (liner) allows for great reduction in friction of piston ring-liner-piston assembly. This assembly shows around 50 per cent of overall friction loss of combustion engine. The new face of the piston ring forces developing of new materials for the cylinder sleeves. Presented are developed for new range of Daimler-Chrysler engines cylinder barrels made of aluminium alloy. Received material (aluminium alloy) is plastic, highly small-grain, shows (according to the authors) negligible wear on the engine. The new materials need to work with presence of new oils, taking over also the cooling function. This is the next direction in research of tribology of combustion engine and simultaneously a way to increase its efficiency. Allowing for higher operating temperatures of piston ring, especially in the TDC of the fire ring, can leads to mentioned above increase in thermal efficiency which results in better fulfilling of the theoretical thermal cycle realized in real cycle of the combustion engine. This article presents besides feasible changes in the piston-piston ring-cylinder system also changes in the supply system of high-pressure and petrol engines. In the high-pressure engines used are currently high pressure (135/200 MPa) injection supply system. Simultaneously available are fuels with reduced to the minimum sulphur contents. At such high injection pressure and low sulphur contents can appear problems with lubricating in injectors and injector pumps of the supply systems. In the petrol engines two companies (Mitsubishi and PSA) have released engines with direct injections of fuel into the combustion chamber. Injection's pressure equals 60 MPa. Lead free petrol shows low lubricating properties and hence can appear tribological problems. The main fields of interest of tribological research related to combustion engines are summarized in following groups: - developing of modern base of synthetic oil resistant to higher operating temperatures of engine components, particularly piston ring and cylinder sleeve, - applying of ceramic composites in form of antiwear coatings and developing new tribological pair working with them in presence of synthetic oils, - developing new concepts of engines working without lubricating and cooling systems, - other works leading to complete eliminating of sulpur from the diesel fuels.

16

Uniwersalny laboratoryjny sterownik silnika spalinowego

80%

Pokorski J. , Rawski F.

Zeszyty Instytutu Pojazdów / Politechnika Warszawska

|

2002

|

tom z. 2/45

67-72

PL

W pracy zaprezentowano programowalny sterownik laboratoryjny służący do sterowania pracą silnika spalinowego. Jest to w istocie uniwersalny układ kontrolno-pomiarowy przeznaczony zarówno do sterowania pracą silnika w hamowni silnikowej, jak i badań trakcyjnych pojazdu z jednoczesnym sterowaniem silnikiem znajdującym się w tym pojeździe. Istotną cechą tego układu, odróżniającą go od innych tego typu sterowników jest fakt, że mikroprocesor sterujący pochodzi bezpośrednio z typowego mikrokomputera PC. Połączenie komputera z programowalnym układem kontrolno-pomiarowym odbywa się za pośrednictwem standardowego portu równoległego CETRONIX. Sterownik ten został zaprojektowany, oprogramowany i uruchomiony w Instytucie Pojazdów Politechniki Warszawskiej. Część elektroniczną sterownika opracował i wykonał inż. Krzysztof Grąziewicz z Instytutu Organizacji Systemów Produkcyjnych Politechniki Warszawskiej.

EN

Programmable measurement and control system for internal combustion engine and transmission has been presented. The system may be used for bench and traction tests.

17

Określenie parametrów ekologicznych stacjonarnego silnika spalinowego zasilanego różnymi paliwami

80%

Brzeżański M. , Mareczek M. , Marek W. , Papuga T.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

|

2014

|

tom z. 1/97

101--108

PL

Przedstawiono wyniki badań wraz z ich analizą, dotyczące prac naukowo-badawczych związanych z wykorzystaniem odpadowych produktów przemysłu chemicznego dla celów energetycznych. W badaniach stosowano paliwa gazowe oraz paliwa ciekłe. Zaprezentowano wyniki badań doświadczalnych parametrów ekologicznych silnika przy zasilaniu wtryskowym. Uzyskane wyniki porównano do wyników badań przeprowadzonych dla standardowego, mieszalnikowego systemu zasilania.

EN

The results of research together with an analysis, concerning the scientific-research works related to the use of waste products of the chemical industry for energy purposes. The studies used gaseous fuels and liquid fuels. The results of experimental studies concerned the ecological performance of engine, which was equipped with an injection system. The results were compared to the results of research carried out, for the standard mixing fuel system.

18

Experimental Investigation on Indicated Pressure and Heat Release for Direct Hydrogen Injection in a Dual Fuel Diesel Engine

80%

Siadkowska K. , Barański G. , Sochaczewski R. , Wendeker M.

Advances in Science and Technology. Research Journal

|

2022

|

tom Vol. 16, no 3

54--66

EN

This paper presents the research results for a diesel and hydrogen fueled engine. The research object is a four-cylinder, four-stroke ADCR engine with a displacement of 2,636 cm3. In the experiments, glow plugs were replaced with compressed hydrogen injectors and a special adapter. Hydrogen was supplied directly into a combustion chamber using a test injector. A hydrogen dose in the tests was changed at selected test points and ranged from 0 to 160 dm3/min. The research were conducted at 1,500 rpm. A hydrogen injection start angle and maximum hydrogen dose were specified from the preliminary experiments. The following parameters were analyzed: indicated mean effective pressure, maximum pressure, crank angle of maximum cylinder pressure occurrence and heat release. The obtained results were statistically analyzed. The conducted analysis focused on determining whether there are significant differences between early and late injection and how these changes affect the measured parameters.

19

Variability of compression ring pressure against the deformed cylinder wall during engine operation

80%

Serdecki W.

Journal of Polish CIMAC

|

2013

|

tom Vol. 8, no 1

73--79

EN

Problems connected with the circumferential distribution of compression ring pressure against the deformed cylinder wall during engine run were presented in this paper. In particular, division of the resultant force pressing the ring against the wall into component connected with ring own elasticity and the one originated from gas pressure was carried out and the influence of each force at individual phases of engine run was evaluated as well. The relationship allowing calculation of the circumferential ring pressure was also established. The paper contains figures and drafts obtained in a course of exemplary calculations of compression ring pressure concerning a running bulldozer engine. These figures show the areas of cylinder wall where so called light slots can appear. Conclusions resulting from the carried out simulation tests are discussed in Summary. The need for further investigations mentioned in presented study was shown as well.

20

Wykorzystanie nowych paliw alternatywnych do zasilania wysokoprężnych silników spalinowych

80%

Zimny J.

Gospodarka Paliwami i Energią

|

2001

|

tom nr 11

10-17