Simulation of heat transfer in shutdown time of engine by conjugate heat transfer

Document Type : Research Article

Authors

1 mechanic

2 department of engineering. Bu-Ali Sina University

Abstract

At the time of engine shutdown, the most probability of boiling exists. The reason is that in a few seconds after stopping of revolution of water pump, the temperature of coolant that is in direct contact with the cylinder head, increases; and if the temperature rising is not considered in design, it can causes film boiling in water jacket of engine. In time of the engine shut down, the cylinder is in contact with piston, and if the cylinder temperature does not drop rapidly, it will cause serious damage to the engine. Also, decreasing in heat transfer from hot gases of combustion chamber to coolant due to stopping the revolution of coolant causes the damage in gasket. Therefore, this damage can be prevented by obtaining distribution of the block temperature during silencing. In this paper, coupled heat-transfer simulation of cooling jacket, block and cylinder head after the engine shut down is carried out with AVL-Fire software. Results of pressure and heat transfer coefficient, heat flux in water jacket and temperature distribution in block and cylinder head are achieved. Finally, effect of engine shutdown is investigated.

Keywords

Main Subjects


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