A cylinder cover partition fatigue life estimation method

Abstract

The invention provides a cylinder cover subarea fatigue life estimation method. The method comprises the following steps: firstly, carrying out simulation analysis on a cylinder cover heat engine coupling failure mechanism, determining a judgment criterion between different failure modes, partitioning the cylinder cover according to the failure modes of different areas, and estimating the fatiguelife of the cylinder cover by adopting different fatigue damage and life prediction models for specific failure modes in a partitioned manner. Aiming at the problems of different material characteristics and different load working conditions of different parts of the cylinder cover, the partition fatigue analysis method is determined to estimate the fatigue life of the cylinder cover, the deviation problem caused by different failure modes in conventional fatigue analysis is reduced, and technical support is provided for adopting software to complete estimation of the fatigue life of the wholecylinder cover at a time.

Description

technical field [0001] The invention belongs to the technical field of fatigue life estimation methods for vehicle engines, and in particular relates to a fatigue life estimation method for cylinder head partitions. Background technique [0002] The cylinder head of modern high-strength engines generally adopts a liquid cooling mode, which requires the functions of intake and exhaust, combustion chamber sealing, and fluid cooling and heat dissipation in a narrow geometric space, making the internal structure of the cylinder head very complicated, and the overall temperature gradient is large. The distribution is very uneven. The fatigue failure mechanism of some key areas of the cylinder head, such as the nose bridge of the fire surface, the nose bridge of the exhaust passage, the wall of the air passage and the installation hole of the fuel injector, is completely different. Some areas have low temperature but the stress changes greatly, some areas have high temperature bu...

AI Technical Summary

Problems solved by technology

The coexistence of multiple failure modes and complex failure mechanisms make it impossible to use a unified damage model and life calculation method in the evaluation of cylinder head fatigue durability. It is necessary to determine the judgment criteria between different failure modes according to the actual failure physics of different parts, and establish The corresponding damage and life prediction model can more comprehensively reflect the durability level of the cylinder head

[0003] Due to the different analysis methods for different failure modes, using the same fatigue damage calculation model and life prediction method cannot effectively satisfy the fatigue assessment of the entire cylinder head, nor can it accurately and effectively calculate the fatigue life of the cylinder head

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