基于分布式动力的翼身融合飞机整流罩气动设计

Aerodynamic design of nacelle of blended-wing-body aircraft with distributed propulsion

整流罩设计对基于分布式动力的翼身融合(BWB)飞机气动特性会产生显著影响。为了揭示在边界层吸入(BLI)效应下整流罩的设计参数对飞机气动特性的影响及其原因,采用计算流体力学(CFD)方法和Morris敏感度分析法对此布局飞机气动特性进行了详细研究,得到了整流罩主要设计参数对飞机气动特性影响的敏感度和耦合关系,并对典型设计参数下的流动特性进行分析。结果表明:对飞机气动特性影响较大的参数是整流罩特征截面2和3的最大厚度,这是因为其增大了当地截面的厚度和弯度,进而影响了整流罩表面的压力分布;在流量系数减小和进气边界弦向位置前移时,最大厚度增大会造成背风面发生局部分离;整流罩特征截面2和3的最大厚度对气动特性具有较强的耦合影响。

Nacelle design has a significant effect on aerodynamic performance of blended-wing-body （BWB） aircraft with distributed propulsion. To clarify the effect and its reason of primary nacelle design pa- rameters on aerodynamic performance of BWB aircraft with boundary layer ingestion （BLI） effect, a detailed study was conducted by computational fluid dynamics （CFD） method and Morris sensitivity analysis method. Sensitivity order and coupled effect of primary design parameters on aerodynamic performance were obtained. Flow details of higher sensitivity and greater coupled effect parameters were analyzed under baseline and alter- native condition. The results show that the relatively most significant parameters are the maximum thickness of section 2 and 3. The main reason is that local thickness and camber increase, and pressure distribution of whole nacelle surface is changed. Leeward local stall will occur as the maximum thickness increases configura- tion when mass flow rate decreases and inlet location along the chord direction moves forward. The coupled effect of the maximum thickness of section 2 and 3 on aerodynamic performance is relatively significant.