Wyniki wyszukiwania - BazTech

1

Study of combustion process with jet-ignition of propane-air mixtures

Sendyka B., Mitianiec W., Noga M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 2

533--543

EN

The paper presents the study of combustion process of a homogenous lean propane-air mixture in the cylindrical combustion chamber ignited by a hot gas jet from the pre-ignition chamber. A rich propane-air mixture in the pre-chamber is ignited by the spark plug and the exhaust gasses flow from the chamber trough the holes in the wall. The mathematical model of gas exchange and energy balance in chambers with a laminar finite-rate model taking into account the two-step Arrhenius chemical kinetics is presented. The work presents results of thermodynamic parameters of the charge obtained in CFD simulations in Fluent and Kiva3v for three configurations: with one hole in the wall of the ignition chamber, with three holes and without an ignition chamber. Modelling and simulation have shown faster burning of the mixture for jet ignition with three holes of the pre-chamber. The results of simulations were verified by experimental studies in the combustion chamber of the same geometry by the Schlieren method. The work presents flame front propagation, pressure traces and pressure increment speed for two mixtures with a different equivalence fuel-air ratio. Experimental results proved the simulation observation of faster flame propagation in the main chamber with three holes.

2

Increase of efficiency of SI engine through the implementation of thermodynamic cycle with additional expansion

Noga M., Sendyka B.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 2

349--355

EN

The paper presents the theoretical basis and practical implementation of the concept of a five-stroke cycle where an additional expansion of the working medium is achieved in a separate cylinder. The work, carried out at the Cracow University of Technology, constitutes a development of the idea of five-stroke engine. This paper proposes a new theoretical thermodynamic cycle that describes the processes occurring in a five-stroke engine. It has been taken into consideration that the expansion ratio of the engine is twice the compression ratio. At the next step an analysis of the thermodynamic cycle with particular emphasis on its thermal efficiency compared to efficiency of four-stroke engine has been shown. In the second part of the article selected research results of the five-stroke engine built based on the existing four-cylinder spark ignition engine have been presented. A comparison of the total efficiency obtained by the engine in the four- and five-stroke version has been provided. Similar comparisons for specific emission of the selected exhaust components have also been given.

3

New design of the five-stroke SI engine

Noga M., Sendyka B.

Journal of KONES

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2013

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Vol. 20, No. 1

239--246

EN

The paper describes design of the five-stroke engine developed in the Chair of Combustion Engines at Cracow University of Technology. The idea of five-stroke engine, in which the expansion ratio is significantly greater than the compression ratio has been presented by the Belgian engineer Gerhard Schmitz. The prototype of such an engine was made by Ilmor Engineering. Engine developers have released results of preliminary research, but there is no detailed information on the toxic exhaust emissions. For this reason, at Cracow University of Technology the research was undertaken to determine the impact of implementing the five-stroke cycle into the engine with spark ignition to reduce toxic emissions and increase total efficiency. To achieve this goal, the test engine was built, which is based on a concept similar to the idea of Gerhard Schmitz, with the difference that it has not been designed from the ground up, and it is based on an existing four-cylinder four-stroke engine. In comparison with the original solution, the engine built in Cracow has a completely different design of timing system, four valves per cylinder and petrol direct injection. This paper presents a detailed description of the engine design and the results of its preliminary research. The results of the tests of the five-stroke engine confirm an increase of specific torque and power (related to unit of engine displacement) and improve of total efficiency within a certain range of the engine map.

4

The determination of increase in charge combustion velocity in a two - cycle Otto - Diesel engine

Sendyka B., Noga M.

Silniki Spalinowe

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2011

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R. 50, nr 3

EN

Investigations and analysis of charge combustion velocity in a two - cycle Otto - Diesel engine were undertaken for the following cases: work of engine with spark ignition and switch to a Diesel cycle by direct injection of ignition dose. During engine work at switch from Otto cycle - i.e. switching off ignition and application of ignition dose - increase in combustion pressure is obtained. Analysis of mass fraction burned (MFB) in the case of work of engine with spark ignition and auto - ignition was carried out. A considerable increase in charge combustion velocity is noticeable. Moreover, during investigations a comparative determination of exhaust gases temperatures was made for an engine with spark ignition as well as for ignition by means of a dose initiating ignition. This was done for two cases of dose injection angle 28 and 30 CA before TDC. Decrease in exhaust gases temperature was found for the case of ignition from the initiating dose.

PL

W pracy podjęto badania i analizę zwiększenia szybkości spalania w silniku dwuobiegowym Otto - Diesel dla następujących przypadków: praca silnika z zapłonem iskrowym i przejście na obieg Diesla przez bezpośredni wtrysk dawki zapłonowej. W trakcie pracy silnika przy przejściu z obiegu Otto, tzn. wyłączenie zapłonu i zastosowanie dawki zapłonowej uzyskano zwiększenie ciśnienia spalania. Przeprowadzono analizę udziału masowego ładunku spalonego dla przypadku pracy silnika z zapłonem iskrowym i zapłonem samoczynnym. Wyraźnie widoczne jest zwiększenie szybkości spalania ładunku. Ponadto w trakcie prowadzonych badań dokonano porównawczego określenia temperatur spalin dla silnika o zapłonie iskrowym oraz dla zapłonu za pomocą dawki inicjującej zapłon dla dwóch przypadków kąta wtrysku tej dawki 28 i 30 OWK przed GMP. Stwierdzono obniżenie temperatury spalin dla zapłonu od dawki inicjującej. W związku z obniżeniem temperatury spalin w przypadku zapłonu od dawki inicjującej wystąpiło również zmniejszenie ilości tlenku azotu w spalinach.

5

System of electronic control of changing ignition from spark-ignition to compression-ignition in a four-stroke engine

Sendyka B., Noga M., Cygnar M.

Silniki Spalinowe

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2011

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R. 50, nr 3

EN

Article presents thorough analysis of implementation of an electronic control system of change from spark ignition to ignition initiated from a pilot dose injection and on the contrary: from auto-ignition to spark ignition. Idea of such controller concerns application of values of parameters such as engine coolant temperature tec, engine load - torque T and also rotational speed n. Condition of switching from spark ignition to auto-ignition is realised after exceeding certain value of function, which it is possible to write A1=f(tec,T,n). In this case electronic system simultaneously activates system of direct injection of ignition dose and switch off supplying of group of ignition coils. In case of reverse switching, takes place to on this same principle on the basis of function's value A2=f(tec,T,n), i.e .ignition system is switched on and system of ignition injection is switched off. Electronic system is controlled by means of computer and determines kind of ignition in the purpose of obtaining the greatest value of total efficiency.

PL

Artykuł przedstawia gruntowną analizę wprowadzenia elektronicznego systemu sterowania przy zmianie z obiegu iskrowego na samoczynny i odwrotnie: z samoczynnego na iskrowy. Idea takiego sterownika polega na wykorzystaniu wartości parametrów takich, jak temperatura cieczy chłodzącej silnik, obciążenie oraz prędkość obrotowa. Warunek przełączania z zapłonu iskrowego na samoczynny odbywa się po przekroczeniu pewnej wartości funkcji, którą można zapisać A1=f(tec,T,n). W tym przypadku elektroniczny system jednocześnie uruchamia układ wtrysku bezpośredniego dawki zapłonowej i wyłącza zasilanie zespołu cewek zapłonowych. W przypadku przełączania odwrotnego, odbywa się to na tej samej zasadzie w oparciu o wartość funkcji A2=f(tec,T,n), tzn. włącza się układ zapłonowy, a wyłączany jest system wtrysku zapłonowego. Układ elektroniczny sterowany komputerem określa rodzaj zapłonu w celu uzyskania największej wartości sprawności ogólnej.

6

Analysis of combustion pressure in a two-cycle engine, Otto and Diesel

Sendyka B., Noga M.

Silniki Spalinowe

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2011

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R. 50, nr 3

EN

Results of investigations performed on a four-stroke internal combustion engine working both with spark ignition and auto-ignition from a fuel dose - according to the patent solution by B. Sendyka - were presented in this paper. The analysis concerned the process of pressure in the cylinder in function of crank angle at work with spark- and auto-ignition initiated from an ignition dose. Traces of changes of pressure rise rate in a function of crank angle and pressure increase in the work space of the engine - which is the result of the combustion process - were given for both ignition and combustion systems. During engine work with combustion initiation from an ignition dose increment of the indicated mean effective pressure as well as caloric and total efficiency was obtained. The results point at improvement of the combustion process in the case of combustion initiation from an ignition dose what influences the considerable increase in total efficiency of an engine as it in the case in engine with auto-ignition.

PL

W artykule opisano wyniki badań prowadzonych na czterosuwowym silniku spalinowym, który ma możliwość pracy, zarówno z zapłonem iskrowym, jak też i samoczynnym od dawki zapłonowej paliwa według rozwiązania patentowego autorstwa B. Sendyki. Analizie poddano przebiegi ciśnienia w cylindrze w funkcji kąta obrotu wału korbowego dla przypadku pracy z zapłonem iskrowym oraz samoczynnym od dawki zapłonowej. Przedstawiono również przebiegi zmian szybkości przyrostu ciśnienia w funkcji kąta obrotu wału korbowego oraz przedstawiono wzrost ciśnienia w przestrzeni roboczej silnika będący wynikiem procesu spalania dla obywu systemów zapłonu i spalania. Podczas pracy silnika z inicjacją spalania od dawki zapłonowej uzyskano przyrost średniego ciśnienia indykowanego, jak też i sprawności cieplnej oraz ogólnej. Uzyskane wyniki wskazują na poprawę przebiegu procesu spalania w przypadku inicjacji spalania od dawki zapłonowej, co ma wpływ na znaczące podniesienie sprawności ogólnej silnika, jak to ma miejsce w silniku o zapłonie samoczynnym.

7

Test bed studies of an engine with combustion initiation from ignition dose of fuel

Sendyka B., Noga M.

Journal of KONES

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2011

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Vol. 18, No. 4

427-509

EN

Results of test bed studies of combustion engine with work possibility with application of spark ignition and combustion from ignition dose injected directly into the combustion chamber were described in this article. In engine working according to the patent solution of Prof. B. Sendyka, during start and work at low rotational speed and low load a system realizing spark ignition of homogenous mixture formed in classical way in the intake manifold is active. For higher rotational speeds and heavy load the ignition system is switched off whereas, injectors of ignition dose injecting fuel by the end of the compression stroke directly into the working space of the engine are activated. The fuel dose injected into the combustion chamber undergoes auto-ignition and in this way the combustion process in the whole volume of the homogenous combustion charge accumulated in the cylinder is initiated. The mass of ignition dose of fuel constitutes about 5 – 10% of the whole fuel mass per working cycle what differs decisively the presented solution from other known engines working according to similar principles. Application of two combustion system in four stroke combustion engine aims at combining the advantages of spark ignition a compression ignition engines. The engine is characterized by easy starting and during work at higher rotational speed and higher load in the mode of ignition from pilot dose exploitation efficiency of energy contained in fuel is higher than for spark ignition engine, this finds direct reflection in increase in total efficiency by over 9% as related to the base value.

8

Simulation of work of an engine working with combustion initiation from ignition dose of fuel

Sendyka B., Mitianiec W., Noga M.

Journal of KONES

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2011

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Vol. 18, No. 3

395-403

EN

The paper presents analysis of fuelling and of the course of combustion process for a two-cycle engine. The main idea of the engine according to patent solution of Prof. B. Sendyka consists in the fact that engine work begins from spark ignition, whereas, at higher load and higher temperature in the cooling system there occurs switching off spark ignition and transition to ignition from an ignition dose injected directly into the combustion chamber. Such an engine possesses two injection systems: one system of multi-point injection which forms homogenous mixture, whereas, the other system of direct injection is used for ignition dose injection only. After injection of the ignition dose of a very small mass combustion is initiated on the basis of formation of auto-ignition centres so as it takes place during knock combustion. Auto-ignition centres initiate combustion of the basic charge. Simulation was carried out in order to perform analysis occurring phenomena of fuel feeding and combustion. Works on it started from elaboration of a computational grid of the engine and subsequently analysis of indicated diagrams of engine work with injection of ignition dose was performed. Analysis was also performed of temperature traces and of traces of charge mass change in the cylinder as well as of participation of the mass of basic fuel dose in the cylinder in function of the crank angle. Moreover visualization of effects of the process of mixture formation and combustion was performed and presented in form of illustrations of charge temperature distribution, fraction of fuel ignition and basic dose vapours in cross-sections of the combustion chamber.

9

Simulation of exhaust gases components formation in engine working with combustion initiation from ignition dose of fuel

Sendyka B., Mitianiec W., Noga M.

Journal of KONES

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2011

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Vol. 18, No. 2

391-396

EN

The paper deals with problems of model analysis of the process of exhaust gases components formation in internal combustion engine working with combustion initiation from ignition dose of fuel injected directly into the working space. In result of scientific-research works carried out in the Chair of Internal Combustion Engines of Cracow University of Technology on the basis of a four stroke engine a driving unit was elaborated which may work both with spark ignition and combustion initiation from a ignition dose of fuel. Application of two combustion systems in engine aimed at combining the advantages of spark ignition with compression ignition driving units. Such an engine is characterized by fuel consumption comparable with that gained by compression ignition engines, whereas, the exhaust gases composition is similar to that occurring in up-to-date spark ignition engines. Similar assumption concern the Homogenous Charge Compression Ignition - HCCI system which seems to be a future solution of internal combustion engines, nevertheless, up till now, in spite of intensive works in many countries all over the world, one did not succeed to control the combustion process in a large range of rotational speeds and loads what would give the possibility of using it in traction application. The solution proposed in the patent application by Prof. B. Sendyka is not burdened with this drawback since the moment of occurrence of volumetric ignition of the formed mixture in the process of filling is tightly connected with the moment of fuel dose injection. In result of simulative studies carried out by use of KIVA-3V software on the discussed solution it was stated that the process of exhaust gases toxic components formation in engine working in the mode of ignition from pilot dose does not depart in generally form from that which occurs at work with spark ignition.

10

Simulation of the work of a spark-ignition engine with a dual-injector fuel system

Sendyka B., Noga M.

Journal of KONES

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2010

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Vol. 17, No. 1

399-410

EN

This paper is about computer modelling of a four-stroke spark-ignition engine with a dual-injector system. Using a KIVA-3V program for Linux, computer simulations were performed for one of the cylinders fuelled by multipoint injection and by the dual-injector system, i. e. with direct injection into the cylinders on top of MPI. The modelling was done for a combustion engine Toyota 2SZ-FE with a dual-injector system. Both simulations were done for the same parameters of engine's work, i.e. at the same RPM of 2000 and the intake pipe pressure of 0.079 MPa. KIVA-3V program models the processes taking place in an internat combustion engine while taking into account physical and chemical phenomena occurring during the formation of a charge and during its combustion. Using a stochastic model of injection the program takes into account the movement of droplets and their dispersion. The results of the simulation show that the dual-injector system has an improved volumetric coefficient, i.e. improved engine performance. An increase in the engine's indicated pressure was also observed; this increases the engine's total efficiency. The intensification of the charge's angular momentum in a cylinder with a dual-injector system can explain the improvements in the course of combustion process. Because the air-fuel mixture was already partially formed in the engine there was a small increase in the unburned hydrocarbons in the cylinder. However, a marked drop in the carbon monoxide and nitric oxide were observed for the dual-injector system. Analyzing the overall results of the simulations one can ascertain a positive impact of using a dual-injector system on the working parameters of a spark-ignition engine.

11

Simulation of injection and combustion processes in 4-stroke spark ignition engine with CNG direct injection

Sendyka B., Mitianiec W., Noga M., Wachulec W.

Journal of KONES

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2010

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Vol. 17, No. 1

373-378

EN

The paper presents results of simulation conducted as afirst step of 4-stroke spark ignition experimental engine testing. The simulations were performed in a KIVA-3Vsoftware, which is intended to carry out a 3-D simulations of engine's processes. The source code of the software has been modified in order to apply it for gas injection. Original version of the software has been designedto simulate liquid fuel injection only. The simulation of direct CNG injection and combustion has been done for stratified and homogenous modes in order to check the assumed injection, ignition and charging parameters. Important assumption is that the injector had only one nozzle with flow area equal to 2 mm2. Two different cases of fuel direct injection for stratified charge have been analysed. In the first case fuel jet was almost vertical. In the other one fuel jet was nearly horizontal. Further testing has been performed using one-cylinder motorcycle 4-stroke SUZUKI DR-Z400S engine adapted to CNG fuelling. Such an engine has a suitable high compression ratio for CNG fuelling. The simulation has confirmed assumed parameters and has shown that one nozzle injector doesn't provide required fuel stream dissipation and piston crown modification is needed to direct fuel stream in spark plug area. However doing simulation requires some effort this example has shown than this is very important step before conducting experimental tests which provides crucial information and helps to avoid expensive mistakes which can be made during experimental engine preparation.

12

Effects of using a dual-injector fuel system on a process of combustion in a spark-ignition engine

Sendyka B., Noga M.

Journal of KONES

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2010

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Vol. 17, No. 1

389-397

EN

This paper analyzes aprocess of combustion in a spark-ignition engine. The aim of the analysis was to determine the differences in the combustion process between the engine with a classic multipoint injection system and a system which injects fuel directly to the cylinders as well. To aid in the analysis the measurements of the high variable pressure in the engine's cylinder against the crankshaft angle were taken. This allowed us to obtain indicated diagrams for both types of engines. To eliminate distortions, both functions were approximated using combined functions. The other basic parameters were also measured: torque, RPM and instantaneous fuel consumption. The analysis of the indicated diagrams yielded an indicated mean pressure and thermal efficiency for both fuel systems. Then, a comprehensive analysis ofpressures in cylinders was performed in order to determine the way the flame spreads in the cylinder for the two types of engines. The results obtained from this analysis show that the speed of combustion is greater for the charge formed by the dual-injector fuel system. The increased speed of the combustion, especially when it reaches a 50% fraction of the exhaust gas in the cylinder, is what accounts for the increase in the indicated mean pressure and the increase in the thermal efficiency of the engine with a dual-injector fuel system. The time of the spreading of the flame, as well as the fast burn period were reduced. The increased efficiency of the combustion process in the cylinder me ans that the heat losses through the cylinder sleeve are greatly reduced. The results of the research in this paper confirm the purposefulness of using a dual-injector fuel system in a spark-ignition engine.

13

Determination of thermal efficiency of the spark ignition systems

Sendyka B., Mitianiec W., Noga M., Wachulec W.

Journal of KONES

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2010

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Vol. 17, No. 1

365-371

EN

The paper presents results of measurements performed to determine thermal efficiency of spark ignition systems. Because of small pressure change after sparking process smali volume chamber has been proposed for measurements. A direct measurement method of pressure increment determination has been chosen. In this method one pressure chamber is used. The caloric chamber isfilledwith nitrogen, which is a neutral gas. It is preferable medium than air because it is one-component gas and it has a precisely-known value of a specific gas constant. The value of speciflc gas constant is reąuested to calculate a value of discharge energy given to the gas. In the chosen method pressure increment in the chamber during spark discharge is measured. The pressure increment in the chamber during ignition is strictly related to the energy of spark discharge. The energy balance calculations determined values of heat los s es for two types of electrodes (normal and "thin") anddifferent initial pressure (p=0 bar and p=25 bar). The maximal value of the thermal efficiency was observedfor the higher value of pressure in chamber and thin electrodes of spark ping. It was also stated, that the higher thermal efficiency for" thin " spark ping electrodes is a result of reduced heat transfer. The paper presents results of the tests carried out in the caloric chamber of 4. l cm3 filled with nitrogen at ambient temperature using PCB transducer direct measurement method. Results of the measurements done using differential pressure transducer for the same parameters like in thefirst measurement method were similar.

14

An impact of using a dual-injection system on a combustion engine's working parameters

Sendyka B., Noga M.

Journal of KONES

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2010

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Vol. 17, No. 1

379-388

EN

The paper analyses the impact of using a dual-injection system on the engine's working parameters. The analysis is based on the results of the test stand research on a four-stroke four-cylinder, spark-ignition engine. Dual-injection system combines the multipoint injection with additional injection directly into the combustion chamber. It is used to increase the performance of an engine without affecting the fuel consumption or the low toxicity of exhaust gas. For the purposes of this research an engine from Toyota Yaris was fitted with the direct injection by installing high pressure injectors on the cylinder head. This engine is factory-equipped with MPL Based on the tests performed four controlling characteristics of the torque and brake specific fuel consumption were prepared. The controlling value was the proportion of the fuel injected into the inlet channel to the fuel injected directly into the combustion chamber. The same relationships were also described in relation to temperature of the exhaust gas and the fraction in volume in the exhaust gas of ingredients such as carbon monoxide, carbon dioxide, unburned hydrocarbons and nitric oxide. Points of measurement were decided upon basedon the existing literature on the subject. The analysis of the test results shows apossibility ofa 2-4% decrease in the brake specific fuel consumption for the dual-injection engine in the low and middle RPM range and for the partial loads. The dual-injection engine also shows a decrease in the nitric oxide's fraction in the exhaust gas and a lower temperature of the exhaust gas. There was a small increase in the carbon monoxide and hydrocarbons.

15

Twin turbocharging system of medium displacement spark ignition engine

Sendyka B., Filipczyk J.

Silniki Spalinowe

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2009

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R. 48, SC2

264--268

EN

The object of the experimental tests was an engine with modified intake end exhaust manifolds. The intake and exhaust manifold modification including only implementation of turbochargers and sensors was done for experimental purposes. The application of two turbochargers system as modification of naturally aspirated spark ignition engine allows to improve torque flexibility rate. There is a possibility to apply the charging system with two turbochargers, with boost pressure control system, in already existing, naturally aspirated engine without decreasing compression ratio and modifying engine’s control system. The application of changeable characteristics of the waste gate valve allows to improv parameters of engine performance in wide range of engine’s rotation speed.

PL

Obiektem badań był silnik ze zmodyfikowanymi układami dolotowym i wylotowym. Modyfikacja układów dolotowego i wylotowego polegała na dostosowaniu ich do zamontowania turbosprężarek oraz czujników pomiarowych. Zastosowanie systemu doładowania dwiema turbosprężarkami pozwoliło na zwiększenie elastyczności momentu obrotowego. Zadowalające rezultaty uzyskano po zamontowaniu układu z dwiema sprężarkami z układem sterowania ciśnieniem doładowania w silniku wolnossącym, bez zmiany stopnia sprężania i modyfikacji układu sterowania. Zastosowano zespół zaworów obejściowych o zmiennej charakterystyce co pozwoliło na poprawę parametrów pracy silnika w szerokim zakresie prędkości obrotowych.

16

Theoretical and experimental analysis of the fuel stream in GDI engine

Sendyka B., Cygnar M.

Silniki Spalinowe

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2009

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R. 48, SC2

338--345

EN

The paper ranges over demonstration of increase in total efficiency of a GDI engine in dependence on the parameters of mixture formation and range of load at determined states of engine work in dependence on the rotational speed of the engine. By use of the newest simulation programme KIVA 3V possibilities of up-to-date methods of calculation of changes of temperatures, pressures, formation of toxic components during the process of stratified charge combustion were presented. The elaborate mathematical models, used in calculations, describing the processes occurring inside the cylinder of the engine permit to create complicated virtual models reflecting the real conditions in a satisfactory way correctness of calculation results is determined by the quality of input data which can be obtained basing on model investigations. In the experimental part investigations on test bed with use of specialist apparatus for visualizations of inside cylinder processes were discussed. By use of visualization observation was performed of the run of the fuel jet from the moment of injection, consequent by rebounding of the fuel from the piston head, on to reaching under the gap between the electrodes of the ignition plug and flame spreading from the moment of ignition till the end of the combustion process. For the determination of the total efficiency of a Gasoline Direct Injection engine, test bed investigations were carried out with the aim to determine the speed and load characteristics of the investigated engine. On this basis, the total efficiency of a GDI engine can be determined.

PL

Zakres pracy obejmuje wykazanie zwiększenia sprawności ogólnej silnika GDI w zależności od parametrów tworzenia mieszanki i zakresu obciążenia w określonych stanach pracy silnika w zależności od prędkości obrotowej silnika. Za pomocą programu symulacyjnego KIVA 3V przedstawione zostały możliwości nowoczesnych metod obliczeniowych przebiegów temperatur, ciśnień, powstawania składników toksycznych w czasie procesu spalania ładunku uwarstwionego. Wykorzystane w obliczeniach skomplikowane modele matematyczne opisujące zachodzące procesy wewnątrz cylindra silnika pozwalają na tworzenie skomplikowanych modeli wirtualnych, które w zadowalający sposób odzwierciedlają warunki rzeczywiste. Poprawność wyników obliczeń zdeterminowana jest jakością danych wejściowych, które możemy uzyskać w oparciu o badania modelowe. W części doświadczalnej omówione zostały badania na stanowisku badawczym z wykorzystaniem specjalistycznej aparatury do wizualizacji procesów wewnątrz cylindra. Zakres badań będzie obejmował przeprowadzenie wizualizacji procesu spalania w silniku GDI dla różnych rodzajów obciążeń i parametrów tworzonej mieszanki paliwowo-powietrznej której celem jest analiza procesów zachodzących wewnątrz cylindra obejmująca przygotowanie mieszanki oraz jej spalanie. Do określenia sprawności ogólnej silnika benzynowego z bezpośrednim wtryskiem paliwa zostały przeprowadzone badania stanowiskowe których celem będzie wyznaczenie charakterystyk prędkościowych i obciążeniowych badanego silnika. Na ich podstawie będzie można określić sprawność ogólną silnika benzynowego z bezpośrednim wtryskiem paliwa.

17

The influence of spray guided charge forming on the work parameters of SI gasoline direct injection engine

Sendyka B., Kudzia S., Rodak Ł., Noga M.

Silniki Spalinowe

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2009

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R. 48, SC2

371--378

EN

In this paper there are presented the results of study of SI gasoline direct injection engines working in wall and spray guided systems. Explorations have been run when throttle valve was opened in 75 % and in 50 %. Characteristics of both engines obtained by means of the study have been put together in order to compare work parameters such as: effective pressure, elementary engine power, specific fuel consumption and total efficiency. That allow qualification an influence of spray guided charge forming on the work parameters of SI gasoline direct injection. In another part of the paper there has been executed the analysis of emission of harmful components of exhaust gas. There has been defined an influence of spray guided charge forming on emission of such ingredients as: oxide carbon, dioxide carbon and hydrocarbons.

PL

W pracy przedstawiono wyniki badań silników ZI z bezpośrednim wtryskiem benzyny pracujących w systemach powierzchniowego i strumieniowego prowadzenia ładunku. Badania przeprowadzone zostały przy 75% oraz 50% otwarciu przepustnicy. Uzyskane w wyniku badań charakterystyki obu silników zostały zestawione w celu porównania parametrów roboczych takich jak: Ciśnienie efektywne, moc jednostkowa, jednostkowe zużycie paliwa oraz sprawność ogólna. Pozwoliło to na określenie wpływu strumieniowego tworzenia ładunku na parametry robocze silnika ZI o bezpośrednim wtrysku benzyny. W dalszej części pracy poddano analizie emisję szkodliwych składników spalin. Określono wpływ strumieniowego tworzenia ładunku na emisję takich składników jak: tlenek węgla, dwutlenek węgla, oraz węglowodory.

18

Modification of the SI engine parameters with adaptation control of compression ratio

Sendyka B., Soczówka J.

Silniki Spalinowe

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2009

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R. 48, SC2

326--330

EN

The first part of the publication comprises the idea of controlling compression ratio in the SI engine. It is also shown the impact of flexible stage of compression on the parameters of the engine and improving them. The publication also reveals the system of adaptive control and benefits gained from it. Moreover, the factors influencing the controlling system, forces operating on controlling system by variable compression ratio are also presented. The second part of the publication presents the results of experimental researches on engines with adaptation controlling of flexible compression ratio. There are also shown charts of the engine performance to the limits of ranges for controlling taking into consideration the lowest and highest range of compression in the function of rotational speed. The last part includes conclusions concerning benefits from applying the flexible compression ratio and adaptation controlling system. It also mentions possibilities of adapting the system to stock production.

PL

W pierwszej części publikacji zawarta jest idea sterowania stopniem sprężania w silniku ZI. Przedstawiono wpływ zmiennego stopnia sprężania na parametry silnika i polepszenie tych parametrów. Pokazany jest układ adaptacyjnego sterowania oraz korzyści uzyskane z jego zastosowania. Przedstawiono także czynniki wpływające na układ sterowania, siły działające na układ sterowania zmiennym stopniem sprężania. Opisano główne elementy składowe układu sterowania oraz wielkości sterujące układem. W drugiej części publikacji przedstawiono wyniki badań eksperymentalnego silnika z adaptacyjnym sterowaniem zmiennego stopnia sprężania. Przestawiono wykresy sprawności ogólnej silnika w granicznych zakresach sterowania dla najmniejszego i największego stopnia sprężania w funkcji prędkości obrotowej dla jednakowych obciążeń. W końcowej części zawarto wnioski na temat korzyści płynących z zastosowania zmiennego stopnia sprężania oraz adaptacyjnego układu sterowania. Opisano możliwość przystosowania takiego układu do produkcji seryjnej.

19

Modelling of dynamic fuel flow rate of high-pressure injector for DISI engine

Sendyka B., Noga M.

Silniki Spalinowe

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2009

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R. 48, SC2

290--293

EN

The paper contains a comparison of dynamic flow rate calculations and laboratory investigations outcome of high-pressure, electromagnetic controlled fuel injector used in direct injection spark ignition engine. The proposed model has both an analytical and empirical character. Some of the values of input parameters were calculated mathematically, while others as flow factor and injector opening delay were measured on the test bed. Injector investigations were conducted on the test stand, in which required injection pressure was obtained pumplessly, by use of compressed nitrogen. The results of calculations were confronted with the measurement outcome and high results convergence was obtained. It confirms correctness of mathematical model and encourages its application to similar fuel injectors without obligation of laboratory measurement. Knowledge of injector dynamic flow rate is fundamental for its choice to particular engine.

PL

Artykuł zawiera konfrontację wyników badań doświadczalnych z analizą modelową charakterystyki dawkowania wysokociśnieniowego, elektromagnetycznie sterowanego wtryskiwacza paliwa przeznaczonego do turbodoładowanych silników o zapłonie iskrowym z bezpośrednim wtryskiem benzyny. Opracowany model miał charakter analityczno – empiryczny. Niektóre z wartości wielkości wejściowych potrzebnych do opracowania modelu zostały wyznaczone na drodze obliczeń matematycznych, inne ustalono w sposób doświadczalny. Badania eksperymentalne wtryskiwacza prowadzono na specjalnie do tego celu skonstruowanym stanowisku doświadczalnym z bezpompowym, pneumatycznym wymuszeniem wymaganego ciśnienia wtrysku. Porównanie wyników eksperymentów z obliczeniami wskazuje na ich dużą zgodność Oznacza, że model obliczeniowy może być stosowany przy wyznaczaniu charakterystyk dawkowania podobnych wtryskiwaczy paliwa. Znajomość charakterystyki dawkowania jest podstawowym warunkiem prawidłowego doboru wtryskiwacza do konkretnego silnika spalinowego.

20

Influence of turbocharge on work parameters of SI gasoline direct injection engine with spray guided system of load forming

Sendyka B., Kudzia S.

Silniki Spalinowe

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2009

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R. 48, SC2

360--364

EN

In this paper there is presented constructional solution of charged SI engine with spray guided gasoline direct injection. There are submitted results of this engine study obtained with partial (75 % and in 50 %) opening of a throttle valve. In further part of the paper the extracted results are compared with testing effects of this engine in version without of charge that was gained earlier. There are compared characteristics of such parameters as: power, torque, specific fuel consumption. That let the authors define the influence of turbocharged SI engine with spray guided gasoline direct injection on its work parameters. Then the analysis of total efficiency of the engine with spray guided load forming in uncharged version and the engine with wall guided gasoline direct injection has been come off.

PL

W pracy przedstawiono rozwiązanie konstrukcyjne doładowanego silnika ZI z bezpośrednim wtryskiem benzyny o strumieniowym tworzeniu ładunku. Zaprezentowane zostały wyniki badań tego silnika uzyskane przy częściowych (50% i 75%) otwarciach przepustnicy. W dalszej części pracy porównano uzyskane wyniki z uzyskanymi wcześniej wynikami badań tego silnika w wersji bez doładowania. Porównano przebiegi takich parametrów jak moc, moment obrotowy, jednostkowe zużycie paliwa. Pozwoliło to na określenie wpływu turbodoładowania silnika ZI o strumieniowym tworzeniu ładunku na jego parametry robocze. Następnie dokonano również analizy charakterystyk sprawności ogólnej zarówno silnika o strumieniowym tworzeniu ładunku w wersji wolnossącej i doładowanej jak również silnika o powierzchniowym tworzeniu ładunku.