动态失速的发生会在直升机旋翼桨叶和桨毂上产生高的交变扭转振动载荷,并限制直升机高速重载状态下的使用包线。本文利用计算流体力学(CFD)方法对基于充气前缘(ILE)技术的SC1095旋翼翼型动态失速抑制进行研究,分析了ILE抑制动态失速的控制机理,获得了ILE结构布置和充放气方式对动态失速的影响规律。研究表明:ILE可以有效抑制动态失速的发生;ILE最大膨胀程度越大,其抑制动态失速的效果越好,但膨胀程度过大后抑制效果开始减弱;ILE在翼型上仰至最大迎角时恰好达到最大膨胀状态,其对动态失速的抑制效果最好;ILE保持最大膨胀状态的时间长短对抑制效果影响不大;在翼型上仰至不同迎角时开始对ILE充气会对动态失速抑制有较大影响;ILE整流段与翼型连接位置对动态失速抑制有很大影响,整流段越长,抑制效果越好。
The occurrence of dynamic stall will result in high vibration torque loads and limit the flight envelope of a helicopter at high speed and load.Through the method of computational fluid dynamics(CFD),dynamic stall suppression for SC1095 helicopter rotor airfoil based on inflatable leading edge(ILE)technology is studied.The control mechanism of dynamic stall suppression and the effect of structure and inflating process of ILE are analyzed.The result shows that the dynamic stall suppression method based on ILE is effective.The bigger the expansion of the ILE,the better the effect of the ILE on dynamic stall suppression.However,if the ILE is too great,the effect will become weak.If the expansion of the ILE reaches the maximum when the airfoil pitches to the maximum angle of attack,the best control performance can be achieved.The duration of the maximum expansion state of the ILE has minor effect on the control performance.The angle of attack at which the ILE starts to swell has a great effect on the control ability.The position which connects the ILE and the airfoil has a great effect on dynamic stall suppression.A longer fairing section of the ILE has a better effect on dynamic stall suppression.