- Tytuł:
- The modeling of the heat loads in the exhaust valve from and without regard of the carbon deposit
- Autorzy:
-
Jędrusik, D.
Gustof, P. - Powiązania:
- https://bibliotekanauki.pl/articles/243988.pdf
- Data publikacji:
- 2010
- Wydawca:
- Instytut Techniczny Wojsk Lotniczych
- Tematy:
-
numerical techniques
analysis and modelling of heat loads
valve
carbon deposit
FEM - Opis:
- This paper presents the modelling of the heat loads in the exhaust valve from and without regard of carbon deposit in initial phase of work of the turbocharged Diesel engine by using the two-zone combustion model, finite elements method (FES) and program Cosmos/M. In order to illustrate the problem the valve face is divided into two equal areas, then it was assumed that one of them is covered with a thin layer of carbon deposit. Modelling was conducted based on the boundary conditions III kind as a function of time, which describes the convective heat transfer coefficient and the temperature of the surrounding surfaces of valve. As a result of the calculations was compared obtained temperature distribution on the surfaces of the valve - with and without carbon deposit. The study also performed an analysis of the stress distribution that arises in the valve by the presence of the carbon deposit on the surface of the face valve. The analysis showed that the face valve heats up unevenly, more slowly on the side of the carbon deposit. Moreover small increase of the temperature causes the increase of the stress values. Maximum values of stresses do not appear in a valve face under a layer of carbon deposit but on the line distributing the surface covered with carbon deposit and without carbon deposit, near the valve face. These stresses cause the growth of microcracks in the area of the valve face, which finally give occasion to the defect of material, the damage of the valve and engine failure
- Źródło:
-
Journal of KONES; 2010, 17, 3; 173-179
1231-4005
2354-0133 - Pojawia się w:
- Journal of KONES
- Dostawca treści:
- Biblioteka Nauki