In order to obtain the multi-parameter loading spectrum and joint probability distribution of the low-pressure turbine shaft of an aeroengine under service conditions,based on the aerodynamic similarity criterion of the engine,the aerodynamic load model was established by using the multiple nonlinear regression method.Through the reasonable simplification of the rotor and support structure,the maneuver load model was established by using the structural mechanics theory.Combined with the in-flight measurement parameters of the engine in service,the aerodynamic torque,aerodynamic axial force,and dynamic bending moment profile of the low-pressure turbine shaft were rapidly converted.On this basis,the peak-valley detection and Rainflow counting were carried out on the load profile to form the peak-valley cycle matrix of the load.In order to consider the correlation between loads,the kernel density method was used to estimate the marginal probability distribution of various load variables,and the Copula function was used to construct the joint probability distribution function of the low pressure turbine shaft load,and the optimal distribution function was determined through the goodness of fit test.The results show that compared with the statistical data,the joint probability distribution function established has better calculation accuracy and can meet the needs of engineering applications.
关键词
低压涡轮轴/气动载荷/机动载荷/Copula函数/联合概率分布函数/航空发动机
Key words
low pressure turbine shaft/aerodynamic load/maneuver load/Copula function/joint probability distribution function/aeroengine
维普
万方数据