大型客机增升构型缝翼除冰状态失速特性

Stall performance of high-lift configuration of large civil aircraft with slat de-icing

在防/除冰系统工作前提下翼面前缘残余积冰对全机失速特性的影响是评估系统效能是否达标的直接依据。针对中外翼区域重点防护的大型客机增升构型除冰方案,基于数值模拟方法对比分析了缝翼未结冰、未除冰、除冰状态下的失速特性。数值模拟结论表明虽然中外翼防/除冰防护区域较同类民机型号有所缩减,但仍能维持内翼始发分离流动形态、保证临界迎角附近的纵向力矩安定性、有效拓展失速边界。当前方案取消当地结冰防护的空气动力学依据是短舱外侧固有的下洗-展向流动综合效应已能充分削弱来流迎角影响,进而抑制局部结冰诱导的流动分离。研究结论可为防护区域设计优化及大型客机结冰适航取证提供理论依据。

Under the working condition of the anti-icing/de-icing system,the influence of residual ice on the stall performance of aircraft is the direct basis for evaluating whether the system efficiency meets the design standard.Aiming at the protection scheme of the outboard wing for a high-lift configuration of large civil aircraft,we compare the stall and separation characteristics under the conditions of slat without icing/icing/de-icing with the numerical simulation method.Despite the reduction of the protection area scheme of outboard wing for a high-lift configuration compared with similar civil aircraft,the current scheme can still keep the separation pattern occurring from inboard,ensure the longitudinal moment stability near the critical angle of attack,and effectively expand the stall boundary.The aerodynamic basis for canceling the local protection is the inherent comprehensive effect of downwash and spanwise flow outside the nacelle,which will weaken the impact of the angle of attack and inhibit the flow separation induced by local icing.The conclusions of this paper provide a theoretical basis for the design optimization of protection area and the icing certification of large civil aircraft.