关键词: 阵风减缓, 控制策略, 模态阻尼增强, 阵风感知, 大展弦比机翼, 风洞试验, 翼根弯矩, 翼尖过载

Abstract:

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 forward 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-aspect-ratio wing of an elastic aircraft scale model as the research object. The experimental results showed that the two controllers 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 controller 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 essentially an open loop controller， which means its influence on aircraft dynamic behavior can be ignored， whereas it relies greatly on accurate gust detection.

Key words: gust alleviation, control strategy, modal damping enhanced, gust sensing, high-aspect-ratio wing, wind tunnel test, wing root bending moment, wing tip acceleration