主动式气动滑片对翼型气动及噪声特性影响研究

Impacts of Active Aerodynamic Sliding Vane on the Aerodynamic and Noise Characteristics of Airfoils

动态失速现象严重影响风力机气动性能,在翼型前缘布置主动式气动滑片可有效改善失速现象。为此基于NACA0012翼型,通过数值模拟研究气动滑片对翼型气动性能及噪声特性的影响。结果表明:前缘气动滑片可有效提高翼型上仰过程中的气动性能,较原始翼型气动滑片翼型的平均升力系数提高24.2%、阻力系数降低11.7%;翼型上仰过程中,气动滑片可抑制前缘分离涡向尾缘发展,延缓前缘与尾缘分离涡的融合,阻止分离涡从翼型表面脱落;气动滑片并未增加翼型噪声水平,但降低了翼型尾缘压力功率谱主频;当改变翼型折合频率时,气动滑片翼型的总声压级与原始翼型保持一致。

The dynamic stall phenomenon seriously affects the aerodynamic performance of the wind turbine,while the arrangement of active aerodynamic sliding vanes on the leading edge of the airfoil can effectively improve the stall phenomenon.Therefore,based on NACA0012 airfoil,the impacts of aerodynamic sliding vane on airfoil aerodynamic performance and noise characteristics are studied by the numerical simulation method.The results show that the active aerodynamic sliding vane on the leading edge can effectively improve the aerodynamic performance of the airfoil during its pitch-up process.Compared to the original airfoil,the average lift coefficient of the aerodynamic sliding vane airfoil is increased by 24.2%and the drag coefficient is reduced by 11.7%.During the pitch-up process of airfoil,the aerodynamic sliding vane can inhibit the leading edge separation vortex from moving to the trailing edge,delay the fusion of the leading edge and trailing edge separation vortexes,and prevent the separation vortex from falling off the airfoil surface.The aerodynamic sliding vane does not increase the airfoil noise level,but it can reduce the main frequency of the airfoil trailing edge pressure power spectrum;when the airfoil reduced frequency is changed,the total sound pressure level of the aerodynamic sliding vane airfoil remains the same as the original airfoil.