Dynamic Optimization Of Reliability For The Turbine Engine Frame Foundation Based On Kriging Model

Since 1970s, with the increase of the volume of steam turbine, the vibration of the foundation of steam turbine is restricted strictly. The dynamic optimization design of the foundation of steam turbine is an important front topic all over the world.To date, there are many studies about dynamic optimization for the deterministic structure, in which the structure's parameters and loads both are determinate. But in fact, many factors have random properties. So the optimization for deterministic structures does not satisfy the needs of the engineering design.A reliable dynamic optimization method based on the Kriging model is proposed to design the turbine engine frame foundation in this paper. The structural weight and reliability for maximum the forced vibration amplitude are considered as two target functions, and the sizing variables and the co-ordinates of the nodes of the beams and columns are selected as design variables.Kriging method can build the approximate mapping relationship between objectives and the design variables, replacing the FE analysis of dynamic responses and Reliability that are time consuming in the optimization. ANSYS software is used to analyze the dynamic responses and Reliability, which has good simulation accuracy. The multi-level optimization method is used to solve the dynamic optimization problem of the steam turbine foundation. The optimization problem is divided into two subproblems on the basis of different effects on structural behaviour of different kinds of design variables. The two optimization phases are alternately done to obtain optimization solution. Numerical Examples show that the method has advantages over the SLP method. The method is suitable for design of complex engineering structures.