Experimental Study of Dynamical Airfoil and Aerodynamic Prediction
Zheyu Shi,
Kaiwen Zhou,
Chen Qin,
Xin Wen
Affiliations
Zheyu Shi
College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211100, China
Kaiwen Zhou
Key Lab of Education Ministry for Power Machinery and Engineering School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
Chen Qin
Low Speed Aerodynamics Institute of China Aerodynamics Research and Development Center, Mianyang 621000, China
Xin Wen
Key Lab of Education Ministry for Power Machinery and Engineering School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
Dynamic stall is a critical limiting factor for airfoil aerodynamics and a challenging problem for active flow control. In this experimental study, dynamic stall was measured by high-frequency surface pressure tapes and pressure-sensitive paint (PSP). The influence of the oscillation frequency was examined. Dynamic mode decomposition (DMD) with time-delay embedding was proposed to predict the pressure field on the oscillating airfoil based on scattered pressure measurements. DMD with time-delay embedding was able to reconstruct and predict the dynamic stall based on scattered measurements with much higher accuracy than standard DMD. The reconstruction accuracy of this method increased with the number of delay steps, but this also prolonged the computation time. In summary, using the Koopman operator obtained by DMD with time-delay embedding, the future dynamic pressure on an oscillating airfoil can be accurately predicted. This method provides powerful support for active flow control of dynamic stall.
