Zhong Jingjun is a professor and Ph.D. advisor in the Marine Engineering College at Dalian Maritime University. His current research interest lies in the area of turbomachinery aerodynamic. Corresponding author. Tel.: + 86 411 84726935. E-mail addresses: zhongjj@dlmu.edu.cn (J. Zhong) Han Shaobing is a Ph.D. student in the Marine Engineering College at Dalian Maritime University. His research interest lies in the area of turbomachinery aerodynamic. E-mail addresses: hanshaobing@ 126.com (S. Han).