1. Key Laboratory of Process Heat Transfer and Energy Saving of Henan Province, School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou, P.R, China
2. Rotor & Transmission Research Department, China Helicopter Research and Development Institute, Tianjin, P.R, China
3. Department of Applied Mechanics and Engineering, Sun Yat-sen University, Shenzhen, P.R, China