史泽奇, 刘勇, 钟伯文, 等. 声涡相互作用下翼型分离泡内流动动力学特征[J]. 空气动力学学报, 2023, 41(2): 29−37. doi: 10.7638/kqdlxxb-2021.0308
引用本文: 史泽奇, 刘勇, 钟伯文, 等. 声涡相互作用下翼型分离泡内流动动力学特征[J]. 空气动力学学报, 2023, 41(2): 29−37. doi: 10.7638/kqdlxxb-2021.0308
SHI Z Q, LIU Y, ZHONG B W, et al. Hydrodynamic characteristics in separation bubbles of airfoil under acoustic vortex interaction[J]. Acta Aerodynamica Sinica, 2023, 41(2): 29−37. doi: 10.7638/kqdlxxb-2021.0308
Citation: SHI Z Q, LIU Y, ZHONG B W, et al. Hydrodynamic characteristics in separation bubbles of airfoil under acoustic vortex interaction[J]. Acta Aerodynamica Sinica, 2023, 41(2): 29−37. doi: 10.7638/kqdlxxb-2021.0308

声涡相互作用下翼型分离泡内流动动力学特征

Hydrodynamic characteristics in separation bubbles of airfoil under acoustic vortex interaction

  • 摘要: 基于LBM-LES方法对中等雷诺数下NACA0012翼型气动噪声进行了直接模拟,得到了声涡相互作用下气动噪声声场和流场,分析了剪切层内流体动力学特征。结果表明:翼型壁面附近剪切层内,扰动从分离前 T-S不稳定分离后向K-H不稳定转变,K-H不稳定对扰动的增长起重要作用;分离泡内湍流强度显著增长直至转捩成湍流,但流动再附后,湍流强度有所降低;750 Hz的大尺度旋涡结构是在分离泡内形成并发展成稳定结构,而2次和3次谐波频率对应的旋涡结构形成于流动转捩后,在分离泡外发展成稳定结构,说明远场2次及3次谐波纯音噪声和750 Hz主纯音噪声生成机理不同。

     

    Abstract: Based on the LBM-LES method, aeroacoustic of the NACA0012 airfoil at medium Reynolds numbers was directly simulated. The flow field and aeroacoustic field under acoustic vortex interaction were obtained, and the hydrodynamic characteristics in the shear layer were analyzed. The results show that in the shear layer near the airfoil surface, the T-S wave turns into the K-H instability after the flow separation, and the K-H instability plays an important role in the growth of the disturbance. Turbulence intensity in the separation bubble increases significantly until transition to turbulence, but the turbulence intensity decreases again after the flow reattachment. The large-scale vortex structure of 750 Hz is formed and developed into a stable structure inside the separation bubble, while the vortex structures corresponding to the 2nd and 3rd harmonics are formed after the transition, and developed into stable structures outside the separation bubble. It suggests that the generation mechanism of the 2nd and 3rd harmonic tonal noise is different from that of the 750 Hz fundamental one.

     

/

返回文章
返回