In view of existing problems in optimization of a rotor-bearing system with dynamic performance constraints

the following improvements were made. Firstly

influence of clearance was considered in the optimization model. Secondly

a hybrid algorithm based on evolutionary algorithm/line search method was proposed. In the proposed algorithm

there were two optimization processes

global searching process using evolutionary algorithm to obtain an optimal solution and local searching starting with the optimal solution by line search method. Numerical results show that: the clearance has great influence on optimization results. The proposed algorithm overcomes the difficulty in choosing initial value for line search method

with higher success rate under the same calculation accuracy.