Turbine blade interval damage tolerance analysis method

Abstract

The invention relates to a turbine blade interval damage tolerance analysis method, and provides an interval analysis method for crack propagation life under the condition of sample shortage. In the crack structure, a novel parallelepiped model is introduced in the method to measure the situation that relevant interval parameters and independent interval parameters are contained at the same time due to the fact that part of the parameters are correlated, such as two crack growth rate constants, and part of the parameters are independent parameters, such as loads and crack sizes. Through the parallelepiped model, most relevant interval parameters are unified and normalized into an independent standard hypercube, and in the standard space, the upper and lower boundaries of the fatigue crackpropagation life of the turbine blade are predicted by adopting a subinterval analysis method. According to the method, independent and related interval variables can be considered at the same time, the problem of large uncertainty of parameters is solved, and engineering practicability of turbine blade damage tolerance uncertainty analysis is promoted.

Description

technical field [0001] The invention relates to a turbine blade of an aero-engine, in particular to a damage tolerance analysis method for a turbine blade section based on a sub-interval method. Background technique [0002] Turbine blades are the core components of aero-engines, gas turbines, etc. They rotate at high speed under the action of high-temperature and high-velocity gas. The turbine blades are subjected to strong gas thrust and bending stress. Repeated frequent start-stop and variable-condition operation make Turbine blades are prone to fatigue fractures in an alternating stress environment, and it is very important to conduct damage tolerance analysis to ensure their safe operation. In the service environment, the blade is usually affected by uncertain factors, and the crack growth life is no longer a definite value. These uncertain factors must be taken into account in the damage tolerance analysis to ensure the safety of the structure. Probabilistic damage to...

AI Technical Summary

Problems solved by technology

Probabilistic damage tolerance can better make up for this defect, especially when it comes to the high-precision and high-cost structure of aero-engine turbine blades, but due to the lack of experimental data, it is usually difficult to construct an accurate probability density function of parameters for probabilistic damage tolerance analysis

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