Wyniki wyszukiwania - BazTech

1

Wykorzystanie pomiaru poziomu hałasu w czasie badań oporów ruchu w układzie gniazdo - zawór - prowadnica dla bezkrzywkowego napędu zaworu

Siczek K.

Silniki Spalinowe

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2011

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R. 50, nr 3

PL

Przeprowadzono badania eksperymentalne na stanowisku, którego schemat zamieszczono w artykule. Obiektem badań były napędzane magnetoelektrycznie zawory stalowe i tytanowe współpracujące z żeliwnymi prowadnicami i gniazdami. Celem badań było uzyskanie wartości parametrów charakteryzujących pracę układu gniazdo - zawór - prowadnica. Na stanowisku badano wznios i przyspieszenie zaworu, siłę uderzenia zaworu o gniazdo, siłę oporów tarcia trzonka zaworu o prowadnicę, temperaturę gniazda i temperaturę prowadnicy. Ponadto mierzono poziom hałasu uderzenia zaworu o gniazdo. Badania przeprowadzono dla różnych wartości wzniosu zaworu, częstotliwości wymuszenia oraz temperatury pracy elementów. W wyniku pomiarów uzyskano wykresy poziomu hałasu w funkcji częstotliwości i czasu, zamieszczone w artykule. Opracowano także model stanowiska badawczego z użyciem Metody Elementów Skończonych. W modelu tym uzyskano rozkłady ciśnienia akustycznego i poziomy hałasu, zamieszczone w artykule. Uzyskane wyniki wskazują na nieliniowy wzrost poziomu hałasu w funkcji częstotliwości wymuszenia, zaś rozkłady ciśnienia akustycznego sugerują miejsce umiejscowienia mikrofonu pomiarowego w czasie badań.

EN

Experimental researches have been carried out on the research stand, which scheme has been given in the article. Driven magneto electrically, steel and titanium valves mating with guides and seat inserts made of cast iron have been the object of investigations. The aim of the study has been to derive the parameters characterizing the work of the assembly seat insert - valve - guide. It has been studied the lift and acceleration of the valve, the valve impact force into seat insert, the friction force between valve stem and the guide, the temperature of the guide and of seat insert. The sound level from the impact of valve into its seat insert has been measured, either. Tests have been performed for different values of the valve lift, the frequency of excitation and the temperature for components. The graphs obtained by measuring the sound level as a function of frequency and time, have been included in the article. Also a model of the research stand has been developed using Finite Element Method. In this model it has been obtained distributions of sound pressure and of sound level, contained in the article. The results indicate the non-linear increase in noise levels as a function of excitation frequency, and sound pressure distributions suggest that the measurement microphone placement position during testing.

2

Research on the tribological parameters for materials couples used for valves, valve guides and seat inserts

Siczek K., Kuchar M.

Tribologia

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2010

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nr 5

253-262

EN

Research on the tribological properties of TiAl alloys used for valves mating with valve guides and seat inserts, made of cast iron, has been done. The aim of the research has been to obtain values of the coefficient of friction for such tribological pairs and to simulate the dynamics of the material sample – rotating plate assembly, characteristic used in the research stand. The modified research stand is presented in the article. During research the values of the coefficient of friction, the temperature of sample, the level of sound and the acceleration of material sample were measured. The model of the research stand was for the simulation of the dynamics for the material sample – rotating plate assembly. The plots of the coefficient of friction vs. loading, slide velocity, and the duration of the motion of material sample in respect to the rotating plate are presented in the article. Using simulation results, the values of the damping coefficient were estimated, which allow one to obtain the value for the amplitude of the modelled motion for the material sample in respect to the rotating plate near to the value of the amplitude for the real motion. This estimation allows one to forecast the dynamics of the mentioned assembly for other values of velocity and loading.

PL

Przeprowadzono badania własności tribologicznych stopów TiAl, używanych dla zaworów współpracujących z żeliwnymi prowadnicami i gniazdami. Celem badań było uzyskanie wartości współczynnika tarcia dla tych par ciernych i symulacja dynamiki układu próbka materiału–wirująca tarcza, odpowiadającej wykorzystywanemu stanowisku badawczemu. W artykule przedstawiono zmodyfikowany tribotester typu pin-on-disc. Podczas badań mierzono wartości współczynnika tarcia, temperatury próbki, poziomu hałasu i przyspieszenia próbki materiału, a ich zależności od prędkości, obciążenia i liczby obrotów przedstawiono na wykresach. Opracowano model tribotestera do symulacji parametrów dynamicznych układu próbka materiału–wirująca tarcza. W oparciu o wyniki symulacji oszacowano wartości współczynników tłumienia, pozwalające uzyskać symulowana amplitudę ruchu próbki względem wirującej tarczy zbliżoną do amplitudy rzeczywistego ruchu. Określenie tego współczynnika tłumienia pozwala przewidywać parametry układu przy innych wartościach prędkości i obciążenia.

3

Tribological properties of the seat insert - valve - guide assembly for valve driven magnetoelectrically

Siczek K., Siczek K.

Journal of KONES

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2010

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Vol. 17, No. 4

439-445

EN

The researches have been carried out, where the object has been the set of two friction couples: valve stem - valve guide and valve seat - seat insert. The camless driven valve has been common for each of such cases. The analyzed valve has been driven by magnetoelectrical drive. The speciał research stand has been elaborated and its scheme has been presented in the article. It has been measured the valve lift and valve acceleration, the impact force, the friction force, temperature values for valve guide and for seat insert, sound level during impacting on the stand. The aim of researches has been to determine the dynamic parameters, the friction force between valve stem and valve guide, the impact force for valve impacting seat insert vs. frequency and valve lift. The analyzed valves have mated with seat inserts and valve guides made of cast iron, in oil absence. The valves have been made of TiAl6Zr4Sn2Mo2 alloy. The researched friction couples have operated in temperature equal 293 K. The increase of frequency has resulted in small changes for values of lift and in greater changes of acceleration, during valve impact into its seat insert. The greatest values of impact force and acceleration have been for the small, middle and high values of valve lift, either. The ratio of impact force and valve acceleration has changed in thin bands. The friction force has decreased slightly with frequency increase and has decreased with valve lift increase. The sound level has increased with the frequency increase, and has not been dependent upon valve lift.

4

The simulation researches on the wear for elements of the seat insert-valve-valve guide assembly

Siczek K., Kuchar M.

Journal of KONES

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2010

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Vol. 17, No. 4

431-438

EN

The researches have been carried out, where the object has been the elements of valve trains in the different combustion engines. Those elements have been valve, valve guide and seat insert. The analysed valves have been driven by special camshaft, with the cams of trapezoid shape. The special research stand has been elaborated and its scheme has been presented in the article. The mentioned research stand has been driven by electric motor. The rotational velocity of the camshaft has been controlled and measured. The aim of the researches has been to obtain values of wear for valve, seat insert, valve guide vs. valve lift, and rpm of camshaft. The dynamic parameters have been analyzed for the seat insert - valve - valve guide assembly, experimentally and by simulation either. During researches the values of valve lift, of valve acceleration, of temperature for seat insert and additionally sound level have been measured. The wear of valve, seat insert and valve guide has been measured, basing on their initial and post-research geometry. The results of experimental researches obtained for different materials for valve, valve guide and seat insert have been presented in the article. The simulation model of the analyzed seat insert - valve - valve guide assembly has been elaborated and presented in the article. Such model has been needed to calculate the values o f the settle velocityfor the analyzed valve. The wear of titanium valve has been a little greater than of the steel valve, the wear of cast iron seat insert mating with steel valve has been much greater than for titanium valve case. The wear of valve guides, made of bronze has been several times less than those of cast iron.

5

The researches on the tribological properties of elements of the seat insert-valve-valve guide assembly

Siczek K.

Journal of KONES

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2010

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Vol. 17, No. 4

423-430

EN

The researches have been carried out, where the object has been the elements of valve trains in the different combustion engines. Those elements have been valve, valve guide and seat insert. The analysed valves have been driven by special camshaft, with the cams of trapezoid shape. The special research stand has been elaborated and its scheme has been presented in the article. The mentioned research stand has been driven by electric motor. The rotational velocity of the camshaft has been controlled and measured. The aim of the researches has been to obtain values of wear for valve, seat insert, valve guide vs. valve lift, and rpm of camshaft. The dynamic parameters have been analyzed for the seat insert - valve - valve guide assembly, experimentally and by simulation either. During researches the values of valve lift, of valve acceleration, of temperature for seat insert and additionally sound level have been measured. The wear of valve, seat insert and valve guide has been measured, basing on their initial and post-research geometry. The results of experimental researches obtained for different materials for valve, valve guide and seat insert have been presented in the article. The simulation model of the analyzed seat insert - valve - valve guide assembly has been elaborated and presented in the article. Such model has been needed to calculate the values o f the settle velocityfor the analyzed valve. The wear of titanium valve has been a little greater than of the steel valve, the wear of cast iron seat insert mating with steel valve has been much greater than for titanium valve case. The wear of valve guides, made of bronze has been several times less than those of cast iron.