Experimental and numerical study on dynamic stall under a large Reynolds number

Advances in Aerodynamics

Research

Yongwei Gao¹  Binbin Wei²  Shuling Hu² 

[1] School of Aeronautics, Northwestern Polytechnical University, 710072, Xi’an, China;School of Aerospace Engineering, Xi’an Jiaotong University, 710049, Xi’an, China;

关键词: Dynamic stall;    Dynamic stall vortex (DSV);    Leading edge vortex (LEV);    Time-frequency analysis;    Wavelet analysis;   

DOI  :  10.1186/s42774-023-00146-0

 received in 2022-12-06, accepted in 2023-02-28,  发布年份 2023

来源: Springer

【 摘 要 】

Dynamic stall under large Reynolds numbers and large reduced frequencies has a significant effect on the performance of the wind turbine blades, helicopter rotors, etc. So the dynamic stall physics of the NACA0012 airfoil under a large Reynolds number of Re = 1.5 × 106 was studied using experimental and numerical methods. The reduced frequency range was k = 0.035 – 0.1. The unsteady flow field in dynamic stall was studied in detail by using the transient pressure measurement and the numerical simulation based on the unsteady Reynolds-averaged Navier-Stokes (URANS) equation. And the time-frequency characteristics of the dynamic stall were studied using the wavelet analysis. The study showed that the aerodynamic performance during the dynamic stall was dominated by the shear layer vortex (SLV) and the leading edge vortex (LEV), and the phase difference between the SLV and the LEV was the key factor in the existence of the bimodal characteristics of the aerodynamic force/moment. There was a significant linear correlation between the negative peak of the vortex-induced Cp and the Cn in the reduced frequency range studied in this paper. During the convection of the near-wall LEV to the trailing edge, the high-frequency features firstly decay, and the multi-scale structures of the LEV become more significant as the reduced frequency gradually increases.

【 授权许可】

CC BY   
© The Author(s) 2023

【 图 表 】

41116_2023_36_Article_IEq731.gif

Fig. 6

41116_2023_36_Article_IEq720.gif

41116_2023_36_Article_IEq716.gif

41116_2023_36_Article_IEq710.gif

41116_2023_36_Article_IEq706.gif

40517_2023_258_Article_IEq40.gif

41116_2023_36_Article_IEq698.gif

41116_2023_36_Article_IEq692.gif

41116_2023_36_Article_IEq686.gif

41116_2023_36_Article_IEq680.gif

41116_2023_36_Article_IEq675.gif

41116_2023_36_Article_IEq664.gif

41116_2023_36_Article_IEq644.gif

41116_2023_36_Article_IEq619.gif

41116_2023_36_Article_IEq615.gif

41116_2023_36_Article_IEq508.gif