斜置平板的低速风洞实验研究

摘要

利用油流法和烟线法相结合的流动显示技术对不同斜掠角和迎角组合下的斜置平板进行了流场显示和和天平测力实验研究.油流显示结果揭示了斜置平板表面分离流动和再附流动的流动特征；烟线显示结果则揭示了斜置平板周围的涡系结构,从而解释了油流显示中所观察到的现象.通过天平测力,我们得到了斜置平板的滚转力矩特性和升力特性.实验结果表明:在小迎角下,随着模型斜掠角度的增加,一条展向发展的涡流动生成于模型的后掠段,该涡流动使滚转力矩保持为相对较小的正值；大迎角下,从斜置平板模型的前掠尖点生成了一股沿展向发展的涡流动,且随着模型斜掠角度的增加,涡流动的影响范围从模型的前掠段扩展到了后掠段,从而使滚转力矩先减小后增大.%An integrated method of oil flow visualization and smoke visualization was used to study an oblique plate with different sweep angles at different angles of attack and force measurements were also conducted.The oil flow visualization reveals the flow separation and reattachment characteristics on the surface of the oblique plate.The smoke visualization shows the three dimensional vortex structure above the oblique plate so as to demonstrate and interpret the flow pattern captured in the oil flow visualization.The behaviors of lift and rolling moment were acquired by the force measurements.The experiment shows that,with increasing sweep angles,a spanwise vortex flow is generated in the middle and back-swept region of the plate when it is positioned at small attack angles,which offers a relatively small positive rolling moment.On the other hand,at high angles of attack,a strong vortex starts from the forward-swept apex and develops along the spanwise direction,whose range of influence extends from the forward-swept to the back-swept section,causing the rolling moments to decrease at first and then increase again with increasing sweep angles.