Wyniki wyszukiwania - Biblioteka Nauki

1

Funkcja przejścia w systemach sekwencyjnego fazowanego wtrysku paliwa gazowego

100%

Flekiewicz B. , Flekiewicz M.

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

225--232

PL

W artykule przedstawiono rolę funkcji przejścia w systemie sekwencyjnego fazowanego zasilania paliwem gazowym oraz zasadnicze czynniki decydujące o prawidłowości jej konstrukcji.

EN

The role of transfer function in sequential gas injection system, and main factors describing its proper construction has been presented in this paper.

2

On board recognition of different fuels in SI engines with the use of dimensional and non-dimensional vibration signal parameters

80%

Fabiś P. , Flekiewicz B. , Flekiewicz M.

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tom R. 48, nr 1

69-75

EN

Gaseous fuels such as natural gas and propane butane mixtures are currently the most popular fuels for dual fuel internal combustion engines. Gaseous fuels are more resistant to knocking than conventional liquid fuels they mix better with air. There have been many published works on the use of gaseous fuels but the problem of the combustion noise, as a very important source of acoustic discomfort is not getting enough attention. Combustion noise occurs in a direct and indirect form. It is transmitted throughout the engine block as a vibration at a different spectrum of frequencies. In this study an attempt has been made to correlate the combustion noise with the operating parameters of an engine fueled with LPG, CNG and CNG-hydrogen mixtures as compared to petrol fueled engine. Signals of multiple resonance in the combustion chamber and corresponding vibration signals of the cylinder block of engine have been considered for one combustion cycle. A four cylinder, 1.6 dm3 spark-ignition engine converted to run on LPG, CNG and CNG-hydrogen mixtures has been tested in the project. A well known diagnostic parameter was used for comparison of the engine noise for its operation on gasoline and alternative fuels. A new non-dimensional indicator has also been proposed for the engine vibration estimation purposes the Increase Wavelet Ratio precisely described in the paper.

PL

Paliwa gazowe, takie jak mieszanki propanu butanu czy gaz ziemny są obecnie najpopularniejszymi paliwami zasilającymi silniki spalinowe. Paliwa gazowe znane są z większej odporności na spalanie detonacyjne niż paliwa płynne oraz łatwiejszego wymieszania z powietrzem. Wiele prac poświecono zasilaniu silników paliwami gazowymi, lecz problemu hałasu w trakcie spalania, jako bardzo ważnego źródła dyskomfortu, do tej pory nikt nie rozpatrywał. Hałas procesu spalania można podzielić na wewnętrzny i zewnętrzny. Wewnętrzny hałas jest transmitowany przez ścianki bloku silnika przy różnej częstotliwości. W artykule przedstawiono wyniki analiz sygnału drganiowego ścianki bloku silnika przy zasilaniu różnymi paliwami. Silnik o ZI o pojemności 1,6 dm3 przystosowano do zasilania paliwem LPG, CNG oraz mieszankami CNG i wodoru. Przeprowadzono badania wpływu obciążenia i prędkości obrotowej na poziom drgań bloku silnika. Do oceny wyników badań użyto znanego wskaźnika bezwymiarowego. W artykule zaproponowano także nowy wskaźnik bezwymiarowy do oceny drgań bloku silnika. Jest to przyrost współczynnika falkowego.

3

Recognition of fuel feeding SI engines with use of dimensional and nondimensional vibration parameters

80%

Flekiewicz M. , Fabiś P. , Flekiewicz B.

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tom Vol. 14, No. 3

153-162

EN

The availability of gaseous fuels like natural gas and propane butane mixtures has lead to worldwide popularity of internal combustion engines running dual fuel or alternatively gas powered. They are known as fuels more resistant to knocking than conventional liquid fuels and as ones less pollutant, their better mixing with air is also well recognized. There have been many published works on the use of gaseous fuels but actually the problem of the combustion noise, as a very important source of acoustic discomfort is not receiving attention. Combustion noise occurs in two forms, direct and indirect. It is transmitted throughout the engine block as a vibration at a different spectrum of frequencies. In this study an attempt is made to correlate the combustion noise to the operating parameters for LPG and CNG powered engine as compared to petrol fuelled engine. Combustion pressure and vibration of cylinder block data are measured and presented for engine running on LPG/CNG and compared to the results obtained for engine fed by petrol. Signals of multiple resonances in combustion chamber and corresponding vibration signals of cylinder block of engine were considered for one combustion cycle. A four cylinder, 1.6 dm3 spark-ignition engine converted to run on LPG and CNG was tested in the project. The engine test stand was fully computerized and the cylinder pressure data, acceleration of vibration of engine block, crank angle data was stored on a PC. The influence of engine speed, load on combustion and engine block vibration was examined for all fuels. A few of well know diagnostic parameters were used for comparison of the engine noise for operation on petrol, LPG and CNG.