弹性机翼阵风减缓控制策略风洞试验

Wind tunnel test on gust alleviation control strategies of elastic wing

介绍了2种用于弹性机翼阵风减缓的控制策略。第1种控制策略是模态阻尼增强的阵风减缓(MDEGA),通过反馈翼尖振动速度驱动副翼做卸载偏转,从而减缓机翼的动载荷及振动。第2种控制策略是基于阵风感知的阵风抑制(GSBGS),由阵风探测器感知阵风速度并前馈给副翼做出偏转,利用副翼操纵力抵消阵风载荷。为验证2种控制策略的实施效果,以某弹性飞机缩比模型的大展弦比机翼为研究对象,进行了阵风载荷减缓原理风洞试验。试验结果表明2种控制器对机翼一弯模态的阵风响应减缓效果显著,翼根弯矩和翼尖过载峰值的减缓量均超过50%。与MDEGA相比GSBGS对峰值外频率点阵风响应的减缓更加有效。2种控制策略各具特点,可为工程设计提供参考:MDEGA等效于增加结构阻尼,不需要精确测量阵风,但受气动伺服弹性稳定性约束;GSBGS是开环控制,不改变飞机动态特性,但严重依赖于阵风探测的精度。

Two control strategies for gust alleviation of elastic wing are introduced.The first control strategy is Modal Damping Enhanced Gust Alleviation(MDEGA).The ailerons are driven to deflect in unloading direction by feedback of wing tip vibration velocity,so as to alleviate the dynamic load and vibration of the wing.The other control strategy is called Gust Sensing Based Gust Suppression(GSBGS).The gust detector senses the gust velocity and feeds it for⁃ward to actuate ailerons.Then the control force is generated on aileron to counteract the gust load.In order to verify the implemental effect of these two control strategies,a principle wind tunnel test is conducted with the high-aspectratio wing of an elastic aircraft scale model as the research object.The experimental results showed that the two con⁃trollers both significantly reduced the gust response of the 1st wing bending mode and the peak reduction ratio in terms of wing root bending moment as well as wing tip acceleration exceeded 50%.Compared with MDEGA,GSBGS con⁃troller is more effective on gust alleviation at frequencies other than the peak frequency.The two strategies have their own characteristics which can provide reference for engineering design:MDEGA is equivalent to increasing structural damping which is independent of gust measurement but constrained by aeroservoelastic stability;GBSGS is essen⁃tially an open loop controller,which means its influence on aircraft dynamic behavior can be ignored,whereas it relies greatly on accurate gust detection.