变来流下翼型动态失速的协同射流控制数值模拟  

Numerical simulation on dynamic stall control of airfoil based on co-flow jet under variable free stream

作　　者：贾天昊 高超[1] 许和勇[1] 徐泽阳 JIA Tianhao;GAO Chao;XU Heyong;XU Zeyang(National Key Laboratory of Science and Technology on Aerodynamic Design and Research,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北工业大学翼型、叶栅空气动力学国家级重点实验室,西安710072

出　　处：《空气动力学学报》2023年第9期59-69,共11页Acta Aerodynamica Sinica

基　　金：国家自然科学基金(12172299,11972306)。

摘　　要：针对直升机前飞时旋翼在变来流下出现动态失速的问题,发展了基于协同射流的翼型动态失速控制方法。选取NACA0012翼型为研究对象,基于转捩SST湍流模型求解非定常雷诺平均Navier-Stokes方程,开展不同参数下协同射流控制翼型动态失速的数值模拟。研究结果表明,协同射流能够有效抑制变来流条件下的翼型动态失速。在变来流下,射流流道对翼型原始气动特性产生不利影响,功率系数的增长速度快于射流动量系数的增加,协同射流存在具有较好控制效果的最佳工作区间。协同射流通过与主流掺混来加速涡系演化,以抑制动态失速,通过增强弦向气流的动能以克服逆压梯度,从而抑制流动分离和促进流动再附着。在马赫数0.283、减缩频率0.151、前进比0.25的条件下,协同射流使翼型升力提高、阻力下降、负俯仰力矩峰降低、流动再附着提前,翼型气动特性得到明显改善。Aiming at the problem of dynamic stall of helicopter rotors under variable free stream during forward flight,a dynamic stall control method of airfoils based on the co-flow jet(CFJ)is developed.Taking NACA0012 airfoil as the research object,the unsteady Reynolds-averaged Navier-Stokes equations are solved based on the transition SST turbulence model,and numerical simulations of the dynamic stall of airfoils controlled by CFJ under different parameters are carried out.The results show that CFJ can effectively suppress the dynamic stall of airfoils.Under the condition of variable free stream,the jet channel has a negative impact on the original aerodynamic characteristics of the airfoil,and the power coefficient increases much faster than the jet momentum coefficient.There is an optimal working condition for CFJ to achieve the best control effect.CFJ accelerates the evolution of multi-vortex by mixing with the mainstream to suppress the dynamic stall,and enhances the kinetic energy of the chordwise flow to overcome the adverse pressure gradient to suppress flow separation and promote flow reattachment.Under the condition of Mach number 0.283,reducing frequency 0.151 and advance ratio 0.25,CFJ can increase the lift of the airfoil,reduce the drag and the negative pitching moment peak,and advance the reattachment of the flow.The overall aerodynamic characteristics of the airfoil are obviously improved by the CFJ control.

关 键 词：动态失速 非定常 协同射流 变来流 前进比 

分 类 号：TP69[自动化与计算机技术—控制理论与控制工程] O358[自动化与计算机技术—控制科学与工程] TJ011.5[理学—流体力学]