1. Center for Advanced Jet Engineering Technologies (CaJET), Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Ministry of Education), School of Mechanical Engineering, Shandong University, Jinan 250061, China;
2. Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China;
3. Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA 15261