1. Analysis and Testing Center, Huangshan University, Huangshan, Anhui 245041, China
2. Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
3. Department of Aero Oil and Material, Air Force Logistics College, Xuzhou, Jiangsu 221000, China