Extremum selection method of random variable for nonlinear dynamic reliability analysis of turbine blade deformation

To effectively select random variable in nonlinear dynamic reliability analysis, the extremum selection method (ESM) is proposed. Firstly, the basic idea was introduced and the mathematical model was established for the ESM. The nonlinear dynamic reliability analysis of turbine blade radial deformation was taken as an example to verify the ESM. The results show that the analysis precision of the ESM is 99.972%, which is almost kept consistent with that of the Monte Carlo method; moreover, the computing time of the ESM is shorter than that of the traditional method. Hence, it is demonstrated that the ESM is able to save calculation time and improve the computational efficiency while keeping the calculation precision for nonlinear dynamic reliability analysis. The present study provides a method to enhance the nonlinear dynamic reliability analysis in selecting the random variables and offers a way to design structure and machine in future work.