Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: engine diagnostic

Sortuj według:

Ogranicz wyniki do:

A method of engines’ diagnosis in operationA method of engines’ diagnosis in operationA method of engines’ diagnosis in operation

100%

Sitnik L. J. , Sroka Z. J. , Wróbel R.

2018

tom Vol. 25, No. 3

403--410

It was found that there are discrepancies between the values of diagnostic parameters obtained in the test and natural exploitation. In addition, no appropriate tests are carried out which would be based on the degree of engine degradation in long-term natural use. One of the reasons is the lack of adequate, non-invasive diagnostic methods. The aim of the work was to show the possibility of creating a new diagnostic parameter of combustion engines in their natural operation. The parameter can be determined by a new method (presented in the article). The method is based on the assumption that the technical condition of the engine can be judged on the basis of the run-up curve, and in particular, on the basis of the linear direction coefficient, which is approximated by the points of the run-up curve at particular moments of the run-up. An additional requirement is that the points of the run-up curve are the average value of the speed from many runs. In addition, the statistical distributions of the speed values in the individual moments of the run-up should be of the same type. The direction coefficient of the straight line determined is a diagnostic parameter. The value of the new coefficient is the value of the straight-line factor. Further works are underway to determine the relationship between the directional coefficient and the technical condition of the engine.

Kryteria doboru parametru diagnostycznego na potrzeby diagnostyki okrętowego silnika spalinowego

86%

Zadrąg R.

tom nr 4

CD-CD

Zmiana niektórych parametrów struktury silnika wpływa na zmianę emisji składników szkodliwych w spalinach. Dotyczy to przede wszystkim uszkodzeń następujących w układzie wymiany ładunku a także w układzie paliwowym i układzie doładowania silnika. W referacie przedstawiono model diagnostyczny silnika, w którym symptomami diagnostycznymi są wskaźniki i charakterystyki emisji gazowych składników spalin. Model uzupełniono wynikami badań na stanowisku jednocylindrowego silnika badawczego ZS. Badanie modelu ukazuje różną wrażliwość zmian wybranych parametrów struktury silnika na parametry diagnostyczne.

Change of some structure parameters of engine influence on the change of toxic compounds emissions. First of all this concerns following damages in the system of load exchange and in the fuel system and supercharge system of engine as well. The paper presents the diagnostic model of engine where diagnostic symptoms are factors and characteristics of gas emissions of exhausts compounds. The model has been supplemented with test results on the test stand of single-cylinder test engine ZS. Test on the model shows different sensitivity of changes of selected structure parameters of engine on diagnostic parameters.

The comparison of vibroacoustic signals taken from an engine before and after repair

72%

Boguś P. P. , Sienicki A. , Wojciechowska E. , Merkisz J.

tom R. 46, nr SC3

300-306

The paper presents the researches on the state of diesel locomotive engines before and after repair with using vibroacoustic signals. The paper describes the methodology, measurement range, the testing equipment and the main data on a locomotive and an engine which was used in acceleration measurements. The paper presents the results of signal analysis which covered the methods like FFT analysis, analysis of main statistical parameters, nonlinear and short-time methods, A nonlinear method presented in the paper is using dominant Lyapunov exponent as a diagnostic parameter. In a short-time analysis applied to vibroacoustic signals some parameters are calculated in a window sliding in time through the signal and next a clustering is perform in resulting parameter space. The first results have shown a significant difference between the values of the main parameters (both linear and nonlinear) for an engine before and after the repair.