Wyniki wyszukiwania - BazTech

1

Thermodynamic analysis of combustion events in the natural gas fuelled SI engine with VVT

Szwaja M., Mazuro P., Szwaja S.

Journal of KONES

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2018

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Vol. 25, No. 4

421--427

EN

The main aim of the research was to investigate influence of overlap of the natural gas fuelled spark ignited engine on the following parameters: Indicated Mean Effective Pressure (IMEP), heat rate release including combustion phases (ignition lag, main combustion phase). The content of the study includes results from processing in-cylinder pressure measurements, heat release rate analysis, combustion phases, and finally the conclusions. The tests were carried out on the test bed including the single cylinder research engine with a displacement volume of 550 cm3. The engine was equipped with independent cam phasors for both intake and exhaust valves, but for this investigation, the exhaust valve timing was fixed (the exhaust cam centre line was fixed at -95 crank angle (CA) deg before Top Dead Centre) and intake valve timing was changed (the intake cam centre line was varied from 90 to 150 CA deg after Top Dead Centre). The overlap was changed in the range from 85 to 25 CA deg. 8 tests series were performed, each singular series consisted of 300 consecutive engine combustion cycles. As observed, by varying the valve overlap it contributes to significant change in the peak combustion pressure, peak of heat release rate, and combustion phases. Summing up, variable valve timing affects compression and expansion strokes by changing polytropic indexes due to various amounts of exhaust residuals trapped in the cylinder. It affects not only engine volumetric efficiency but also the heat release rate and IMEP, so it does engine performance. Thus, variable valve timing can be considered as valuable tool that can be applied to the natural gas fuelled internal combustion engine.

2

Mechanical and thermal stresses issues related to a size of a four-stroke piston based on a Renault Premium DXi11 430 460 EEV engine

Kaliszewski M., Mazuro P.

Journal of KONES

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2018

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Vol. 25, No. 3

275--282

EN

The size of an engine is one of the factors affecting its thermal efficiency. It is known that with an increase of the size of the engine, the cubic capacity and heat generation grows in the third power, whereas thermal losses are proportional only to the second power of the size (due to heat exchange surface). However, the increase in the size of the engine generates some problems related to its mass, rotational speed and heat load, the last of which is a subject of these considerations. In the article, the influence of the piston size on its thermal and mechanical stresses is considered. Similar boundary conditions for both cases were assumed. Simulation of the steady-state heat transfer and mechanical simulation were carried out using the Finite Element Method. In each analysis, both the original version of the piston and its scaled version were considered. The boundary conditions were adopted on the basis of engine catalogue data and available literature. The results of analyses were discussed.

3

Analysis of thermal and mechanical stresses of Renault Premium DXi11 460 EEV four-stroke piston

Kaliszewski M., Mazuro P.

Journal of KONES

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2018

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Vol. 25, No. 2

169--175

EN

In this article the engine piston Renault Premium DXi11 430 460 EEV has been analysed using the Finite Element Method. Analysis consider as well heat transfer phenomenon as the thermal and mechanical strains of the piston. Simulations were performed for the point of engine maximum power. Piston material was assumed to be 40HM (1.7225) steel and its properties are delivered basing on available scientific papers. The simulation assumed mean values of heat transfer coefficient, reference temperature and cycle pressure based on engine data, maximum power engine work simulation in AVL Boost software and literature. Part of boundary condition (e.g. cylinder wall temperature) was assumed basing on authors’ engineering intuition and experience. The resulting temperature distribution in the piston was implemented for geometrically nonlinear mechanical FEM analysis. Both the analysis of thermal stresses and stresses of the hot piston in the top dead centre were performed.

4

Numerical investigation on low calorific syngas combustion in the opposed-piston engine

Pyszczek R., Mazuro P., Jach A., Teodorczyk A.

Combustion Engines

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2017

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R. 56, nr 2

53--63

EN

The aim of this study was to investigate a possibility of using gaseous fuels of a low calorific value as a fuel for internal combustion engines. Such fuels can come from organic matter decomposition (biogas), oil production (flare gas) or gasification of materials containing carbon (syngas). The utilization of syngas in the barrel type Opposed-Piston (OP) engine arrangement is of particular interest for the authors. A robust design, high mechanical efficiency and relatively easy incorporation of Variable Compression Ratio (VCR) makes the OP engine an ideal candidate for running on a low calorific fuel of various composition. Furthermore, the possibility of online compression ratio adjustment allows for engine the operation in Controlled Auto-Ignition (CAI) mode for high efficiency and low emission. In order to investigate engine operation on low calorific gaseous fuel authors performed 3D CFD numerical simulations of scavenging and combustion processes in the 2-stroke barrel type Opposed-Piston engine with use of the AVL Fire solver. Firstly, engine operation on natural gas with ignition from diesel pilot was analysed as a reference. Then, combustion of syngas in two different modes was investigated – with ignition from diesel pilot and with Controlled Auto-Ignition. Final engine operating points were specified and corresponding emissions were calculated and compared. Results suggest that engine operation on syngas might be limited due to misfire of diesel pilot or excessive heat releas which might lead to knock. A solution proposed by authors for syngas is CAI combustion which can be controlled with application of VCR and with adjustment of air excess ratio. Based on preformed simulations it was shown that low calorific syngas can be used as a fuel for power generation in the Opposed-Piston engine which is currently under development at Warsaw University of Technology.

5

Experimental test stand for development of an opposed-piston engine and initial results

Kalke J., Opaliński M., Mazuro P.

Combustion Engines

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2017

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R. 56, nr 2

76--82

EN

The article presents the reason for developing a 0D predictive and diagnostic model for opposed-piston (OP) engines. Firstly, a description of OP engines, together with their most important advantages and challenges are given together with current research work. Secondly, a PAMAR-4 engine characteristic is presented. After that the proposed 0D predictive model is described and compared with the commercially availible software. Test stand with most important sensors and solutions are presented. After that the custom Engine Control Unit software is characterized together with a 0D diagnostic model. Next part discusses specific challenges that still have to be solved. After that the preliminary test bed results are presented and compared to the 0D simulations. Finally, the summary together with possible future improvement of both 0D predictive model and test bed capabilities are given.

6

Evaluation of the effect of variable compression ratios performance on opposed piston 2-stroke engine

Alqahtani A., Wyszynski M. L., Mazuro P., Xu H.

Combustion Engines

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2017

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R. 56, nr 4

97--106

EN

Numerous skills involving the introduction of (OP) opposed piston engine have been developed in the recent past. Indeed, novel techniques can help to improve the performance of the engine. The aim of this paper is to model and simulate a simple single-cylinder two-stroke opposed-piston engine and minimise fuel consumption and heat loss, using the software programme AVL BOOST™. AVL BOOST is an engine modelling software, which analyses the performance of a modelled single cylinder two-stroke opposed-piston engine by changing desired parameters. In order to meet this aim, experimental results from a unique engine are used to make a comparison with the results obtained from AVL BOOST model. Six combinations of compression ratios (12, 13.5, 15, 16.5, 18 and 19.5) are analysed in this study with the engine speed running at 420 rpm and 1500 rpm. In addition to the compression ratios, the effect of stroke-to-bore (S/B) ratios on OP2S performance is investigated. Various values of S/B ratios, whilst maintaining a constant swept volume, port geometry and combustion timing, and their effect on fuel consumption and heat loss are analysed in this study. A comparison between the two engine speeds with increasing combinations of compression ratios, and the S/B ratios revealed minimal differences in peak pressure, peak temperature, IMEP, ISFC, indicated efficiency and total heat loss. Detailed analyses of these parameters are highlighted in discrete sections of this paper.

7

Compression Auto-Ignition Control in a 2-stroke Barrel-type Opposed-Piston Engine

Pyszczek R., Mazuro P., Teodorczyk A.

Archivum Combustionis

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2017

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Vol. 37 nr 1

25--42

EN

The aim of this study is to investigate a possibility of Compression Auto-Ignition (CAI) control in a turbocharged 2-stroke barrel type Opposed-Piston (OP) engine fueled with a gasoline. The barrel type OP engine arrangement is of particular interest for the authors because of its robust design, high mechanical efficiency and relatively easy incorporation of a Variable Compression Ratio (VCR). A 3D CFD numerical simulations of the scavenging and combustion processes were performed with use of the AVL Fire solver that is based on a Finite Volume Method (FVM) discretization and offers a number of tools dedicated to numerical simulations of working processes in internal combustion engines. The VCR and water injection were considered for the ignition timing control. A number of cases was calculated with different engine compression ratios, different equivalence ratios and different amount of injected water. Results show that proposed measures should be appropriate for controlling the CAI combustion process. Furthermore, application of these solutions in the real engine can significantly contribute to increase in efficiency and decrease in emissions.

8

Investigation into the effect of bore/stroke ratio on a single cylinder two stroke opposed piston engin

Alqahtani A. M., Wyszynski M. L., Mazuro P.

Journal of KONES

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2016

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Vol. 23, No. 2

9--16

EN

Opposed-piston (OP) engine’s promising fuel efficiency has attracted the interest of automotive industry in the recent years. The opposed-piston two-stroke (OP2S) engine technology heightens this fuel efficiency benefit and offers advances in structure, power density and thermal efficiency whilst sustaining its lower cost and weight. Today thermodynamic modelling remains an indispensable and cost effective route in the development and optimisation of internal combustion engines (ICEs). To achieve this goal, the OP2S engine is simulated and validated against experimental results in AVL Boost™, which is hailed as one of the most reliable and advanced engine simulation tools. Detailed analyses of the piston dynamics, heat release, scavenging and heat transfers are highlighted in discrete sections of this paper. Having compared distinct heat release models, the Wiebe 2-Zone model emerged efficacious in replicating the heat release characteristics of the PAMAR™ engine. In comparing the numerical and experimental results, the simulation revealed minimal differences in peak pressure, peak temperature and maximum pressure raise rate, under ±2.5% differences for indicated power, IMEP, indicated thermal efficiency (ITE) and ISFC. Subsequently, confidence taken from the validated numerical model is then deployed to investigate the effect of stroke-to-bore (S/B) ratio on OP2S performance. Three combinations of S/B ratios (0.5, 1.25, and 1.69) with identical swept volume are analysed in this study. Utilisation of the validated model ensured the standardisation of intake, exhaust and the combustion systems in order to isolate the effects of S/B ratio. Results indicate that heat losses decrease with increasing S/B ratio because of the reduced surface area-to-volume in the cylinder. Consequently, an improvement in ITE and mechanical efficiency is observed with reduced ISFC for higher S/B ratios. A tendency of upsurge in combustion efficiency is also evident for higher S/B ratio due to reduced heat transfer near minimum volume of the combustion chamber.

9

Unsteady conjugated heat transfer in cylinder of highly loaded opposed-piston engine

Kalke J., Szczeciński M., Mazuro P.

Combustion Engines

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2016

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R. 55, nr 4

64--72

EN

Paper presents a method of calculating the temperature distribution in cylinder for a 2-stroke, opposed-piston (OP) internal combustion engine (ICE). Development of such machines has been very limited after World War II due to technological and ecological problems [9], therefore progress in numerical modeling for analyzing highly boosted OP engines was also halted. Current technology permits returning to the OP arrangement, where due to better combustion chamber shape it is potentially possible to achieve higher thermodynamic efficiency than in arrangement with the cylinder head [9, 10]. Authors decided to use a general purpose CFD-program (in this case Ansys Fluent) coupled with additional tools to calculate conjugated heat transfer between the load in the cylinder and the cylinder itself to get a 3D temperature distribution in solid body.

PL

Artykuł prezentuje metodę wyznaczania temperatury cylindra dla dwusuwowego silnika wewnętrznego spalania o tłokach przeciwbieżnych (opposed piston – OP). Rozwój takich maszyn po II wojnie światowej został mocno ograniczony z powodu problemów technologicznych i ekologicznych [9] i w związku z tym rozwój modelowania numerycznego, w celu analizy wysoko doładowanych silników typu OP, również został zahamowany. Obecny rozwój techniki pozwala powrócić do konstrukcji typu OP, w których z racji korzystniejszego kształtu komory spalania możliwe jest uzyskanie potencjalnie większej sprawności termodynamicznej niż w układzie z głowicą [9, 10]. Do obliczenia wymiany ciepła między ładunkiem w cylindrze a cylindrem, by otrzymać trójwymiarowy rozkład temperatury w ciele stałym, wykorzystano programu CFD ogólnego zastosowania (w tym przypadku Ansys Fluent) sprzężony z dodatkowymi narzędziami.

10

Review of unconventional gaseous fuels and related problems of reciprocating engines operation

Wrożyna Z., Mazuro P.

Archivum Combustionis

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2016

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Vol. 36 nr 2

105--120

EN

The article contains an overview of unconventional gaseous fuels used for power generation in reciprocating engines. The fuels included: gases originating from the fermentation of organic substances, gases from the gasification of solid fuels and gases which are a byproducts of other processes. Examples of composition of the gaseous fuels and pollution occurring in them were presented and compared with the fuel quality required by manufacturers of gas engines. An analysis of the impact of specific components for the operation of reciprocating engines was made. Solutions to existing problems both which are currently used in operating systems as well as being the only subject of research were proposed. The use of presented gaseous fuels was rated as a probable alternative to fossil fuels and efficient way of process waste utilization.

11

Numerical investigation of the swirl combustion chamber for the Opposed-Piston Compression-Ignition engine

Pyszczek R., Kalke J., Mazuro P.

Archivum Combustionis

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2016

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Vol. 36 nr 2

83--104

EN

The possibility of achieving high thermodynamic efficiency brings opposed-piston (OP) engines back into interest of research centers. If made as 2-stroke, the possibility of unidirectional scavenging arises together with lower engine cost due to removal of unnecessary parts like camshafts or poppet valves. Unfortunately, in the OP design the injection is perpendicular to cylinder axis, which is ineffective with conventional diesel injectors. Following article will present the proposed solution to this particular problem using an externally-attached swirl combustion chamber. The qualitative assessment of ability to meet the design expectations was performed in AVL Fire. The authors describe the CFD model and injector used for simulation. Contour plots and charts are given to compare the results. A variety of geometrical cases were analyzed. The recapitulation gives a critical evaluation of the proposed solution.

12

Tribological Examination of Different Steel Materials after Special Heat Treatment and Salt Bath Nitriding

Opaliński M., Mazuro P., Klasik A., Rostek E.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

1881--1888

EN

The main aim of the presented research was examination of new tribological pairs made of different types of steel. Materials of disc probes were submitted to unusual heat treatment processes and salt bath nitriding. The research is focused on the friction coefficients and mass losses of the material probes. Based on the results it was noticed that the best wear resistant pair was bearing steel 100Cr6 coupled with high speed steel S705. The lowest friction coefficient appeared for the pair bearing steel 100Cr6 and maraging steel C350.

13

Rozwinięcie metody analizy numerycznej wymiany ładunku w silnikach o tłokach przeciwbieżnych

Kalke J., Mazuro P., Sulikowski P.

Combustion Engines

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2015

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R. 54, nr 3

511--519

PL

Moc i sprawność całkowita silników dwusuwowych jest silnie zależna od sprawności wymiany ładunku, dlatego też optymalizacja tego procesu jest krytyczna z punktu widzenia wydajności. Głównym celem tego artykułu jest pokazanie potencjału łączenia ze sobą różnych narzędzi inżynierskich w celu znacznego przyspieszenia fazy koncepcyjnej weryfikacji różnych systemów wymiany ładunku. Proponowany algorytm postępowania używa różnorakich języków programowania do łączenia komercyjnych (w tym przypadku Ansys Workbench, Siemens NX, MathWorks Matlab, Microsoft Excel) i niekomercyjnych pakietów (Cantera) by uzyskać najważniejsze informacje tak wcześnie jak jest to możliwe. Proponowane narzędzie obsługuje model 0-wymiarowy procesu spalania (z zadanym stężeniem gazów wylotowych), podziału geometrii i dyskretyzacji przestrzennej, zautomatyzowanego ustawiania programu obliczeniowego i postprocesora do danych numerycznych, przygotowanych specjalnie dla rozrządu sterowanego tłokami. Przeprowadzono prostą ocenę zaoszczędzonego czasu dzięki zaproponowanej metodzie postępowania. Ostania część jest krytycznym podsumowaniem zaproponowanej metody i wskazuje pewne ciekawe kierunki rozwoju takie jak kosymulacja z programami 1D oraz bardziej zaawansowane modelowanie spalania.

EN

The power and overall efficiency of two-stroke engines are strongly dependent by scavenging efficiency, thus optimization of this process is vital to performance. Main aim of this article is to show the potential of combining different engineering tools to substantially speed-up the conception verification phase of various scavenging systems. The suggested algorithm uses a variety of programming languages to interconnect commercial (in this case Ansys Workbench, Siemens NX, MathWorks Matlab, Microsoft Excel) and non-commercial packages (Cantera) to get the most important information as soon as possible. Presented tools cover 0-D combustion process model (with desired exhaust gases concentration), geometry division and meshing, automated solver-setting and numerical-data postprocessor, prepared especially for piston ported valves. A simple evaluation of time savings by using proposed method was conducted. Last part is a critical sum-up of presented method and pointing out some interesting directions of development, concerning co-simulation with 1D software and more sophisticated combustion modeling.

14

Obliczenia numeryczne wymiany ładunku w silniku dwusuwowym z przeciwbieżnym układem tłoków

Szczeciński M., Mazuro P., Skrobek W.

Combustion Engines

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2015

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R. 54, nr 3

563--569

PL

Dwusuwowe silniki tłokowe z przeciwbieżnym układem tłoków coraz częściej budzą zainteresowanie ośrodków badawczych na całym świecie. Konstrukcje te mają długą historię, a renesans zainteresowania związany jest z szeroką gamą zalet, które oferują. Jedną z nich jest wzdłużny system płukania cylindra. W artykule przed-stawiono proces modelowania wymiany ładunku jako część projektu układu rozrządu badawczego silnika z przeciwbieżnym układem tłoków. Omówiono parametry, których zmiana pozwala kontrolować zastosowane kryteria jakości płukania. Przedstawiono wyniki symulacji numerycznych oraz podkreślono główne wyzwania czekające na konstruktorów projektujących układ rozrządu w podobnej konstrukcji.

EN

Two stroke opposed piston engines increasingly attract an interest among the research centers around the world. This engine architecture has a long story and renaissance of its interest is associated with a wide gamut of benefits they offer. The uniflow cylinder scavenging is definitely one of them. This paper presents a modeling process of the in-cylinder gas exchange as a part of the research engine timing system design. In addition, it highlights dependencies between the timing system design parameters and the scavenging quality factors. Final-ly, the article demonstrates numerical simulation results and takes into consideration main challenges in the piston ported timing system designing.

15

Comparison of flow performance in one- and three-dimensional software for modelling opposed piston engines

Opaliński M., Mazuro P., Wyszyński M.

Archivum Combustionis

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2015

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Vol. 35 nr 1

29--40

EN

Simulating a full engine that includes a turbocharging system is time consuming and demands high power computing capabilities. Simplification of the engine model was considered indispensable to verify different boosting system concepts in reasonable timeframes. An attempt was made to reduce the computing time demand using the one-dimensional Ricardo WAVE software. Comparison of results of selected inlet and exhaust gas parameters of models created in 3D software (Ansys FLUENT) and Ricardo WAVE showed differences between 1 and 12%. Those discrepancies may be acceptable for initial verification of different boosting system concepts. In order to obtain more accurate results it is recommended to link the engine FLUENT model with Ricardo WAVE boosting model.

16

On the high IMEP potential of barrel engines

Mazuro P., Jasiński D., Teodorczyk A.

Silniki Spalinowe

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2011

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R. 50, nr 3

EN

In this work the possibility of very high performance of barrel engine fueled with gasoline is presented. In this engine several new technologies were used in order to achieve the compression assisted ignition (CAI). The control of CAI combustion reagime was obtained by intensive charge stratification and exhaust gas recirculation (EGR). The additional advantage of barrel engine is its axual symmetry which ensures identical conditions in all cylinders. The application of spherical bearings in barrel engine, instead of classical cylindrical ones, allowed for the increase of permissible loads of crank mechanism. Moreover the noise of engine operation at full load has been reduced due to the untypical kinematics of barrel engine crank mechanism and spherical bearings. All these advantageous features resulted in IMEP level of 2.4 MPa for engine fuelling with homogeneous mixture. The maximum rate of pressure rise was at the same time limited to 0.8 MPa/CAD

PL

W pracy przedstawiono możliwość uzyskania bardzo wysokich osiągów w silniku beczkowym zasilanym benzyną. W silniku tym zastosowano szereg rozwiązań, które pozwoliły na uzyskanie kontrolowanego samozapłonu (ang. Controlled Auto-Ignition - CAI). Opanowanie spalania typu CAI osiągnięto dzięki zastosowaniu silnej stratyfikacji oraz kontroli recyrkulacji spalin (ang. Exhaust Gas Recirculation - EGR). Dodatkową zaletą silnika beczkowego jest osiowa symetria silnika zapewniająca identyczne warunki we wszystkich cylindrach. Zastosowanie łożysk sferycznych, zamiast klasycznych walcowych, w silniku beczkowym pozwoliło na zwiększenie dopuszczalnych obciążeń układu korbowego. Dzięki nietypowej kinematyce silnika beczkowego oraz łożyskom sferycznym uzyskano zmniejszenie hałaśliwości pracy silnika przy pełnych obciążeniach. Zalety silnika beczkowego pozwoliły na uzyskanie średniego ciśnienia indykowanego na poziomie 24 bar, przy zasilaniu silnika mieszanką jednorodną, przy jednoczesnym ograniczeniu maksymalnych przyrostów ciśnienia do 8 bar/CAD.

17

Determination of Hydrogen-propane Condensation Curve

Jasiński D., Kapusta L., Teodorczyk A., Mazuro P., Sutkowski M.

Archivum Combustionis

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2010

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Vol. 30 nr 1-2

53-61

EN

Stricter environmental legislations make necessary or even profitable the utilization of gases that are by-products from different production processes and which have been wasted so far. To design the most suitable utilization technology for these gases a detailed knowledge of their properties is required. The parameters of vapour-liquid phase change are crucial for fuel handling. The physical and chemical properties of most commonly used gases are well known but the broad variety of gases produced during different industrial processes has not been investigated yet. The simple, fast and precise method of determination of their condensation curve is very useful. The determination of condensation curve for a gas composed mainly of hydrogen and propane has been described. The measurement method and testing equipment is universal and can be used for various compositions of gases and is also very suitable for gases containing a significant amount of hydrogen.

18

Optimization of the combustion chamber in a 2-stroke barrel engine and comparison with 4-stroke classical crankshaft mechanism engine

Mazuro P, Jaworski P, Teodorczyk A

Silniki Spalinowe

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2009

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R. 48, SC1

254--265

EN

In the paper, the results of numerical optimization of the combustion chamber of a 2-stroke CI barrel engine are presented and the comparison to a 4-stroke engine with traditional crankshaft mechanism is performed. The optimization is made on the basis of CFD simulations performed for different geometrical models of the combustion chamber, specially designed for the barrel engine. The initial conditions for simulations were assumed taking into account the differences in mixture exchange in the chamber after combustion process for different rotational speeds, density, pressure and wall temperature. The simulations were made for various fuel - gasoline (approximated by C8H17) and diesel (simulated by C13H23) with the use of AVL FIRE software. The target was to create a proper chamber for CI and HCCI mode of combustion system. The results indicated that combustion chambers which were acceptable for CI mode are not appropriate for HCCI mode of engine operation. This comes from the characteristics of chemical reactions and fuel injection. The standard injectors on the market for CI and SI engines have different characteristics of injection, fuel brake up, fuel evaporation and mixing with air. It was found that the well operating combustion chamber with one fuel (for example H8C17), in HCCI mode, is not working well for other fuel, like C13H23. These observations must be confirmed during engine bench tests which are planned for near future. The comparison of a 2-stroke barrel engine with the 4-stroke engine with traditional crankshaft mechanism is based on literature data and shows that properly designed combustion process in the barrel engine with its advantages in construction can give much better results than the engine with traditional crankshaft mechanism. The major advantages are: smaller friction losses, smaller fuel consumption, higher engine efficiency, higher power/weight ratio.

19

Internal combustion engines with cylinder axes parallel to drive shaft axis versus conventional crank shaft engines - comparison of mechanical efficiency and losses

Mazuro P., Rychter T., Teodorczyk A.

Silniki Spalinowe

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2007

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R. 46, nr SC1

66-72

EN

Barrel engines are characterized by unconventional construction feature: cylinder axes are parallel to drive shaft axis. The rotation of the central power shaft is created from the reciprocating motion of the pistons with the use of different types of mechanisms, including wobble plate, swash plate or cam disc. Due to complex internal motion their kinematics and dynamics is completely different than that of crankshaft engine. Barrel engines are expected to have a potential to compete with currently used power units, especially in aircraft applications. The paper reviews and compares all classified types of barrel engines with conventional crankshaft engine in terms of kinematics: mechanical losses and mechanicals efficiency. Advanced computations were made for each mechanism to derive formulas describing 3 dimensional movements of barrel engines' parts. Comparison of mechanisms parameters was made with the use of MatLab software. The paper gives a brief idea of barrel engines classification and design. Computations methodology for mathematical description of all mechanisms' kinematics is presented as well as the results of mechanical losses and efficiency comparison. Wobble plate mechanism blocked by gear has been identified as the most promising for further analysis and research.

20

Computational study of transport aircrafts landing gear during touchdown

Mazuro P., Rychter T., Teodorczyk A.

Journal of KONES

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2006

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Vol. 13, No. 3

197-205

EN

The conventional crankshaft piston engines dominate in the automotive industry. Automotive development centers seek for innovations in the engine efficiency, ecology, fuel and air supply, control or economics but the research area mostly refers to conventional constructions. The authors propose to come back to old and forgotten constructions called barrel engines which originate from the period between First and Second World Wars. The design and properties of barrel engines differ a lot from conventional crankshaft engines. The most characteristic feature of barrel engines is that the cylinder axis is parallel to drive shaft axis and due to multiple cylinders they have axial symmetry. Although there are not many historical applications and production experience of barrel engines, the authors believe they may offer a few really significant advantages to contemporary automotive business. The paper presents unique classification of barrel engines specific mechanisms to convert reciprocating motion of the piston to the rotary motion of the crank shaft. The examples of historical applications of each group of mechanisms are given with comments to their mode of action.