Cylinder Head Gasket Leakage Trouble Shooting Analysis 2021-01-1234

The present paper describes a CAE analysis approach to evaluate the transient cylinder head gasket sealing performance of a turbo charged GDI engine in the bench test development. In this approach, both transient gasket sealing force and gasket wear work are calculated to allow design engineers to find out the root cause of cylinder head gasket leakage failures.

In this paper, the details of the method development are described. Firstly how to use and get the cylinder head gasket property are described, which is the basic theory and data for the gasket sealing analysis. A transient heat transfer calculation for accurately simulating the engine thermal shock test is established, which is mapped to the transient gasket sealing calculation as pivotal boundary. The transient gasket sealing calculation which considering the cylinder pressure change, transient thermal load change, bench installation, fretting wear of gasket coating in cycling thermal shock conditions, is different from the traditional steady sealing analysis, it can reflect the comprehensive influence of various factors and simulate the test more truly.

The simulation results show that the local gasket regions with low gasket pressure and high wear work were identified accurately, and the simulation results were consistent with the experimental leakage area.

The scheme of adding the limiting gasket stopper rib locally in the leakage area is proposed. Through local structural shape optimization of gasket, the simulation results show that the gasket sealing pressure is effectively improved and wear work in the leakage area are greatly reduced, finally the optimized gasket has passed the thermal shock test successfully.