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For reducing the heat rejection and enhancing the cylinder head's performance of enduring the thermal loads, the LHR cylinder head with a ceramic insulating layer is presented in this paper. The ceramic insulating layer, with the thickness of 0.0 mm, 0.7mm, 1.0mm and 1.5mm, is adopted respectively to illustrate the effect of thickness of the ceramic layer on the amount of the heat transfer of the cylinder head. Computed results show that the amount of the heat transfer decrease with the growth of the thickness of the ceramic layer. The three-dimensional FEA is used to calculate the cylinder head's mechanical-thermal comprehensive stresses. According to the FEA results, the stresses of characteristic points of the cylinder head with the heat-insulating layer become larger than those of the non-LHR cylinder head. Then, numerical analyses based on the stress-strength interference are performed to evaluate the cylinder head reliability with different thickness ceramic layer.

Free vibration of the blades of one radial-flow turbocharger is analyzed by the finite element method, and the natural frequencies and modes are obtained, the numerical results are in good agreement with the experimental ones. Resonant vibration of the compressor blade and turbine blade is analyzed respectively, then the resonance interference analysis of the blades is presented, the resonance occurrence probabilities of the blades at the rotating operation speed of the turbocharger is obtained, finally the working reliability of the blades is evaluated.

The Fuzzy sets theory into reliability analyses is studied. In this paper, a novel approach is presented to use the finite element analysis as a “numerical experiment” tool, and to find directly, by fuzzy linear regression method, the statistical property of the structure stress. Based on the fuzzy stress-random strength interference model proposed in this paper, the fuzzy reliability of the mechanical structure can be evaluated. The compressor blade of a given turbocharger is then introduced as a realistic example to illustrate the approach.