Wyniki wyszukiwania - Biblioteka Nauki

1

Problems With Representation Of The Oil Film Generating Conditions On The Wankel Engine Cylinder Sliding Surface

100%

Iskra A. , Babiak M.

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tom Vol. 4, no 1

47-54

EN

The fundamental problem with wide application of the Wankel engine is to assure oil film continuity on trochoidal cylinder bearing surface. For the sake of considerable difference between curvature radius of the apex seal sliding surface and the trochoidal cylinder the oil film can be generated on the short fragment of the apex seal. However there is certain field of maneuver in the apex seal shape determination which allows to approach close radiuses of curvature of both elements in the areas where the highest gas forces load is occurred. In the paper simulation of the revised apex seal oil film parameters are presented. Author described also the test stand which is going to be used for experimental verification of the simulation results. Conclusions refer to possibility of replacement the constant radius shape of the apex seal sliding surface with shape that consist of two different curvatures.

2

The oil film parameters of the wankel engine apex seal in aspects of durability of mating elements

80%

Iskra A. , Babiak M. , Kałużny J. , Marszałkowski K.

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tom Vol. 17, No. 4

199-206

EN

The Wankel engine is one of only few alternatives to the reciprocating engines. The advantages such as good value of maximum engine power to its mass ratio are still present and can have great sense in selected fields of application, for example General Aviation. Nevertheless the disadvantages of the Wankel engine design have never lost its importance and still pose an obstacle to wider use of the Wankel engine. One of the main drawbacks is the rotor sealing system design, especially the apex seal where single siat has to fulfil a purpose of conventional engine piston rings pack. Moreover the unfavourable changes of the apex seal angle of attack causes that optimal shape of the apex seal sliding surface, in aspects of the oil film parameters, can not be achieved. These results in worsening of apex seal elements mating conditions, reducing its effectiveness and durability. In the paper authors present results of simulation researches where oil film parameters, for example oil film thickness, which determines apex seal durability, were obtained for different engine operating conditions and various shapes of apex seal sliding surface geometry. The results indicate possible directions during apex seal designing process which should provide oil film continuity in whole rotor angle position range and for wide engine operation conditions range.

3

Flow simulation through wankel engine throttle using computational fluid dynamics

80%

Wendeker M. , Grabowski Ł. , Pietrykowski K. , Magryta P.

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tom Vol. 18, No. 1

677-682

EN

The paper focuses on the airflow through the throttle in the Wankel engine (Aixro XR50). The author's main challenge was to adapt a Wankel engine for hydrogen injection system, which required a very new full electronic throttle to be installed. Thus, an injector adapter and flow meter were mounted in this engine. The engine will be used as a stationary power unit to generate electricity for small households. Using hydrogen instead of hydrocarbon fuel will reduce the emission of green house gases. The simulation was in the AVL Fire using Computational Fluid Dynamic for 9 different throttle opening angles, i.e. ranging from 20 to 90 centigrade, i.e. 20, 30, 40, 50, 60, 70, 80 and 90 centigrade. The boundary conditions being as the pressure at the inlet and outlet of the throttle module correspond to the real values in the engine. The data on the properties of the flowing medium (air) were selected by default from the AVL Fire library. The authors use the k-zeta-ef model of turbulence to simulate flow through a Wankel engine throttle. The simulation results include the distributions of pressure, velocity and stream lines. The dependence of the mass flow rate as a function of the throttle position angle was presented. The turbulence disappears when the throttle opening angle of 60 centigrade is crossed. For full throttle the velocity at the pipe walls decreases to about 12 m/s. The highest velocity throughout the model occurs just where the throttle is mounted.

4

Ocena przydatności silnika Wankla w zastosowaniach wojskowych ze szczególnym uwzględnieniem szczelności komór roboczych

60%

Iskra A. , Babiak M. , Kałużny J.

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tom R. 52 nr 1 (184)

51-58

PL

W artykule przedstawiono rozważania dotyczące zalet silnika Wankla, które w obszarze wybranych zastosowań czynią go bardzo atrakcyjnym źródłem napędu, szczególnie w porównaniu z silnikiem o postępowo-zwrotnym ruchu tłoka. Zalety takie, jak korzystny stosunek uzyskiwanej mocy do masy silnika czy zwartość konstrukcji mogą być kluczowymi czynnikami skłaniającymi do zastosowania tego rodzaju silnika jako źródła napędu. Zwrócono również uwagę na wiele wad i problemów, między innymi niekorzystny kształt komory spalania czy słabą skuteczność i trwałość listew uszczelnienia promieniowego tłoka, których następstwem jest ograniczenie możliwości wykorzystania silnika Wankla.

EN

The paper considers advantages of the Wankel engine. In particular areas these advantages make the Wankel engine attractive as a prime mover especially when compared to reciprocating piston engine. The advantageous value of the maximum power to engine weight ratio and compactness of the engine can be the key factors considered in choosing the engine process. The authors also emphasize some disadvantages of the Wankel engine, such as unfavorable shape of the combustion chamber or durability and reliability of the apex seal which result in limiting applicability of the Wankel engine.

5

Silniki Wankla dla bezzałogowych statków powietrznych

60%

Melnarowicz W.

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tom No. 44

267--274

PL

W artykule przedstawiono możliwości zastosowania silnika z wirującym tłokiem, zwanego silnikiem Wankla, do napędu bezzałogowych statków powietrznych. Opisano zasadę pracy silnika oraz jego wady i zalety. Określono kategorie dronów do których są dedykowane tego typu napędy. Zaprezentowano seryjnie produkowane modułowe silniki Wankla firmy Advanced Innovative Engeeniering o mocach 5-120 KM do napędu bezzałogowych statków powietrznych.

EN

The article presents the possibility of using a rotary piston engine, called the Wankel engine, to drive for unmanned aerial vehicles. It describes the principle of engine operation, its advantages and disadvantages. The article specifies the categories of drones to which these engines are dedicated. The author presents the modular Wankel engine of 5-120 hp for unmanned aerial vehicles, manufactured by Advanced Innovative Engeeniering.

6

Problemy odwzorowania kinematyki listwy uszczelnienia promieniowego silnika Wankla

51%

Iskra A. , Kałużny J. , Babiak M.

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tom R. 105, z. 7-M

223-230

PL

Silnik Wankla używany do napędu trakcyjnego ma wiele zalet, np. takich jak duża koncentracja mocy i marginalne drgania, jednak dotychczas silnik ten nie znalazł szerszego zastosowania praktycznego. Jednym z głównych problemów wynikających z koncepcji silnika Wankla jest uszczelnienie promieniowe wirującego tłoka. W niniejszym artykule przedstawiono problemy symulacji współpracy listwy uszczelnienia promieniowego tłoka silnika Wankla. Omówiono budowę proponowanego stanowiska symulacyjnego oraz możliwości odwzorowania kinematyki w liniowym ruchu postępowym. Przedstawiono charakterystyczne różnice w relacjach geometrycznych elementów uszczelniających, jakie są stosowane w silniku Wankla i klasycznym silniku o posuwisto-zwrotnym ruchu tłoka, które mają znaczący wpływ na parametry filmu olejowego między poruszającymi się elementami. Zbudowane stanowisko badawcze umożliwi zbadanie parametrów filmu olejowego powstającego na powierzchni ślizgowej listwy uszczelniającej, co może mieć kluczowe znaczenie dla rozwiązania istniejących problemów konstrukcyjnych, uniemożliwiających - jak dotychczas - szersze zastosowanie silnika Wankla.

EN

The Wankel engine used to traction drive characterizes oneself with row of advantages like large concentration of power and marginal vibrations, however till now such engine did not find wider practical use. One from main problems resulting from idea of engine Wankel is the apex seal of rotor. In the article problems of tightening slat cooperation simulation are presented. Erected test bed will make possible examining of oil film parameters, what can have key meaning for solutions of existing constructional problems, making impossible as yet wider use of the Wankel engine.

7

Modelling and simulation of working processes in Wankel engine with direct hydrogen injection system

51%

Mitianiec W.

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2015

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tom R. 54, nr 2

42--52

EN

Wankel engines were very attractive in automotive sector almost forty years ago because of small dimensions, compactness, simple design, smoothness of engine work and lack of vibration caused by inertia forces. The disadvantage of such engine was very high pollution, especially of hydrocarbons and carbon monoxide and high fuel consumption. These disadvantages can be eliminated by applying of direct injection of hydrogen and in the aviation sector by applying of fuel with high octane number also at a direct injection system. The main objective of the work is modelling of the thermodynamic process taking place during the scavenge process in such engine. At assumed geometry of the engine, initial and boundary conditions the change of engine parameters such as pressure, temperature, density, heat exchange and volume are calculated on the base of zero-dimensional model as a function of rotation angle of the piston. Forming of the mixture during fuel injection process in compression process gives information about the air excess ratio. The presented model is applicable for different sort of fuels. This work is introduction to a broader analysis of the processes in spatial system. Application of hydrogen reduces of toxic components emission from such engine, but decreases also engine power.

PL

Silnik Wankla byl bardzo interesujący dla przemysłu samochodowego prawie czterdzieści lat temu ze względu na małe wymiary, kompaktowość, prostą konstrukcję, równomierność pracy silnika i brak drgań wywołanych siłami bezwładności. Wadą tego silnika była duża toksyczność emitowanych spalin, szczególnie węglowodorów i tlenków azotu oraz duże zużycie paliwa. Te niedoskonałości silnika mogą być wyeliminowane dzięki zastosowaniu bezpośredniego wtrysku paliwa o dużej liczbie oktanowej lub wodoru. Głównym celem pracy jest modelowanie parametrów termodynamicznych procesów zachodzących w czasie przepłukania w tym silniku. Przy założonych parametrach geometrycznych silnika, warunkach brzegowych i początkowych obliczono zmiany parametrów takich, jak: ciśnienie, temperatura, gęstość, prędkości wlotu i wylotu za pomocą własnego programu komputerowego opartego na modelu 0-D w funkcji kąta obrotu wału korbowego. Tworzenie mieszanki podczas wtrysku paliwa daje informację o współczynniku nadmiaru powietrza. Zaprezentowany model obliczeniowy jest dostosowany do różnego rodzaju paliwa. Praca jest wstępem do szerszej analizy procesów przestrzennych w komorze spalania. Zastosowanie wodoru zmniejsza emisję szkodliwych składników spalin, lecz zmniejsza również moc silnika.

8

Projektowanie adaptera wtryskiwaczy silnika Wankla przy użyciu metody Rapid Prototyping

51%

Wendeker M. , Pietrykowski K. , Magryta P.

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tom nr 7

214-218

PL

W artykule przedstawiono proces wytwarzania adaptera wtryskiwaczy silnika Wankla. Zaprezentowano etap projektowania adaptera w systemie CAD (Catia v5) przy użyciu zawansowanych technik komputerowego wspomagania projektowania. Przedstawiono proces wytwarzania adaptera techniką Rapid Prototyping przy użyciu drukarki 3D - ZPrinter 450 oraz zaprezentowano gotowy element wytworzony za pomocą obróbki CNC.

EN

The article presents the 3D printing process of a Wankel engine injector adapter. The paper presents the design stage of an adapter in a CAD (Catia V5) by using advanced computer-aided design techniques. Article shows the process of printing an adapter using rapid prototyping technique in 3D Printer - ZPrinter 450. In the end the finished item produced by the CNC is presented.

9

Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion

41%

Orkisz M. , Wygonik P. , Kuźniar M. , Kalwara M.

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tom R. 58, nr 3

264--268

EN

Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion The paper presents an analysis of the possibilities of application of a rotating piston engine (Wankel type) as a propulsion for an electric generator in the motor glider propulsion system. This generator would be a part of the propulsion system of a hybrid motor glider using the AOS 71 motor glider airframe. In the research, the rotational characteristics of the LCR 407ti engine were determined experimentally. Driving torque run, power and fuel consumption were determined as a function of engine speed. The obtained results are presented in diagrams. The conceptual diagram of the hybrid drive is presented. The current generator was selected and the effectiveness of the generator and the entire propulsion were assessed from the motor glider's performance point of view. On the basis of the conducted research, conclusions were drawn and there were indicated the objectives and directions of further research on hybrid propulsion with specific aerodynamic and mass limitations of the aircraft.

10

Comparative analysis of pollutants emission by classical and distributed propulsions applied on the AOS motor glider

41%

Orkisz M. , Wygonik P. , Kuźniar M. , Kalwara M.

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2019

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tom R. 58, nr 4

102--106

EN

Comparative analysis of harmful compounds emission of classical and distributed propulsions applied on the AOS motor glider, taking into account the perspective of the development of hybrid propulsions. A novel path is indicated by so-called distributed aircraft propulsion. The advantages and disadvantages of this type of solutions are presented, as well as the conceptual design of the distributed propulsion for the AOS 71 motor glider. In the paper there were compared the emissions of harmful compounds generated by a hybrid power unit developed for the airframe of AOS 71 motor glider - traditional propulsion, so-called focused (one-propeller) and dispersed propulsion (multi-propelled). Functional diagrams of both types of propulsions solutions are presented. Construction and aerodynamic constraints of both propulsions are discussed and comparative analysis is made. In the traditional version of the propulsion (so-called focused propulsion). the propeller is driven by an Emrax 228 electric engine with effective parameters: N = 55 kW, M = 120 Nm. The power source is a battery set with a capacity of 16 Ah and a range extender powered by a LCR 407ti rotating piston engine with maximum power of 28 kW. In the variant of the distributed propulsion. Ten electric engines of AXI 8120 type were used to drive small propellers arranged along the wingspan. The power source in this variant is analogous to the variant with the Emrax electric engine. For the adopted variant of the flight mission of the motor glider. a flight trajectory model was developed, which was used to determine the load of the power unit. In laboratory conditions. emission tests of both propulsions were conducted. The results are summarized in charts and discussed in the conclusions.

11

Comparative analysis of combustion engine and hybrid propulsion unit in aviation application in terms of emission of harmful compounds in the exhausts emitted to the atmosphere

41%

Orkisz M. , Wygonik P. , Kuźniar M. , Kalwara M.

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tom R. 58, nr 3

213--217

EN

Comparative analysis of combustion and hybrid propulsion unit in aviation application in terms of emission of harmful compounds in the exhausts emitted to the atmosphere. For the propulsion of the AOS 71 motor glider, two types of propulsion were planned as development versions. The first analysed propulsion is based on a combustion engine, but of the Wankel type (LCR 814 engine with the power of 55 kW). The second designed propulsion is an hybrid based on a LCR 407 combustion engine with a power of 28 kW, which is connected in series with an electric generator propelling the engine (Emrax 228 engine), total power of the propulsion is 55 kW. The comparison of emissions of harmful compounds emitted to the atmosphere generated by the combustion and hybrid power unit intended for assembly in the AOS 71 motor glider, assuming various loads and methods of hybrid propulsion control, was made. The tests were conducted in laboratory conditions. Several different programs were designed to simulate different energy management methods in a hybrid system, depending on the predicted mission and load of the motor glider. On the basis of laboratory tests, exhaust emission was determined from both propulsions as a function of rotational speed and load. Then, based on the assumed flight trajectory and collected test data, the emission for both propulsions variants was determined. The values of emission parameters were compared and the results were presented in diagrams and discussed in the conclusions.

12

A rotating piston engine with electric generator in serial hybrid propulsion system for use in light aircraft

41%

Kalwara M. , Kuźniar M. , Orkisz M.

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tom R. 60, nr 4

42--45

EN

Analysis of the possibility of using a rotary engine based electric generator to propell a powered sailplane. The paper presents analysis of utilising Wankel type enine as a power input for an electric generator in the motor glider propulsion system. This generator would be a part of the propulsion system of a hybrid motor glider using the AOS 71 motor glider airframe. In the research, the rotational characteristics of the LCR 407ti wankel engine were determined experimentally. Driving torque run, power and fuel consumption were determined as a function of engine speed. The obtained results are presented in diagrams. The conceptual diagram of the hybrid drive is presented. The electric generator was selected and its effectiveness, as well as the effectiveness of entire propulsion system was assessed from the motor glider's performance point of view. Basing on the research conducted, conclusions were drawn and there were indicated the objectives and directions of further research on hybrid propulsion with specific aerodynamic and mass limitations of the aircraft.