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应用基于SST(Shear-Stress-Transport)湍流模型的IDDES(Improved Delayed Detached Eddy Simulation)方法,对大迎角状态下多段翼型缝翼前缘典型角状冰引起的复杂分离流动进行了数值模拟研究。采用后台阶流动标准算例和干净无冰多段翼型分离流动算例对数值方法的可靠性和适用性进行了验证。缝翼结冰状态下的数值模拟结果表明:来流迎角较大时,前缘角状冰将会导致结构相对稳定的流动分离泡产生,分离泡的非定常尾迹会对主翼前缘附近流场产生较为强烈的干扰,抑制了缝道流动的加速效应,使得缝翼增升效率降低。在失速点附近,由于分离泡回流强度随来流迎角而增长,同时脱落旋涡的输运方向逐渐向远离壁面方向偏移,使得尾迹影响区域范围和强度均有所增加。
A numerical simulation of the complicated separation flow induced by the typical angular ice at the leading edge of a multi-section airfoil at high angle of attack is carried out using the IDDES (Modified Delayed Detached Eddy Simulation) method based on the SST (Shear-Stress-Transport) turbulence model . The reliability and applicability of the numerical method are verified by the standard backscattering flow case and the clean ice-free multi-section separation flow case. The results of numerical simulation of the icing condition of the slat show that when the angle of attack is large, the leading edge ice will lead to the relatively stable structure of the flow separation bubble, and the unsteady wake of the separation bubble will affect the flow near the leading edge of the main wing Field produce more intense interference, inhibit the acceleration of seam flow acceleration, making slats reduce the efficiency of the increase. In the vicinity of the stalling point, the strength of the area affected by the wake increases as the return bubble strength increases with the incoming angle of attack. Meanwhile, the transport direction of the shedding vortex gradually shifts away from the wall surface.