低雷诺数多螺旋桨/机翼耦合气动设计

Based on the research of near-space solar-powered unmanned aerial vehicles, the multi-propeller/wing integrated aerodynamic design at high altitude and low Reynolds number is studied. With the analyses of both aerodynamic per-formance and flow characteristics of the typical multi-propeller/wing configuration, a concept for the low Reynolds number multi-propeller/wing coupled aerodynamic design is proposed, which is based on the construction of ideal near-wall flow distribution under multi-propeller-induced effects. And then, the multi-propeller parameters, the sectional airfoil within low Reynolds number regions, and the wing section within higher Reynolds number regions are optimized and studied in sequence. Lastly, both the reliability and efficiency of the proposed multi-propeller/wing coupled aerodynamic design concept are studied by analyzing the optimized results. It shows that the aerodynamic performance of the configuration designed based on the proposed concept is significantly improved when compared with the conventional designed based on optimization of the airfoil at the low Reynolds number. The wing designed based on the proposed coupled processes has a relative drag reduction of 8.8% and a relative lift-to-drag ratio increment of 12.1%, and nearly 64.5% adverse effects induced by the multi-propeller slipstream can be eliminated.