THE SAFETY DESIGN METHOD FOR THE ROTOR SYSTEM WITH FAN BLADE OFF

A safety optimization design method for the rotor system with fan blade off is established by taking the time-varying parameters such as rotor speed and support stiffness as the optimization variables, and the vibration response at the key position of the rotor as the optimization objective. The reduction in the number of optimization objective functions is achieved through correlation analysis and influence rule analysis. The optimization problem of rotor system dynamics is addressed by employing finite element model and radial basis function response surface surrogate model, integrated with NSGA-II genetic algorithm. The results show that the optimization method based on the response surface surrogate model can greatly save the computational time and obtain a smoother Pareto frontier solution. The Pareto solution set of the rotor system with fan blade off can be divided into two regions, corresponding to the structural design ideas of “partial fusing design” and “complete fusing design” respectively. In addition to the steady-state amplitude of the fan disk, the other three objective functions can be reduced by more than 45.0% after optimization. In general, the optimal solution of the corresponding area of “complete fusing design” is better than that of “partial fusing design”.