Optimization design of hybrid laminar flow control wing for flight test

Drag reduction by the laminar flow control technology can significantly reduce aircraft friction and thus exhibits important application prospects. Laminar X-plane is a flight test platform designed to verify the laminar wing design technolo¬gy. The hybrid laminar flow test section is mainly used to verify the delay effed of the leading-edge suction on the transition position. For the hybrid laminar flow wing, the design constraint analysis and preliminary design of the hybrid laminar flow test section are first conducted, and the high-speed aerodynamic optimization design of the wing, pod and pylon shape is then carried out. On this basis, the effects of different suction distributions on suction power, flow rate and transition delay are studied, and the optimal distribution is determined. Finaly the transition characteristics of the final optimized configura- tion are examined through numerical calculation and wind tunnel tests. The results show that the optimized hybrid laminar flow test section has good aerodynamic characteristics^ ^hd the transition suppression effect of the leading-edge suction on the crossflow instability wave can be verified at the design point. The compromised suction distribution can ensure the suction effect in most areas of the suction zone and reduce the suction power and flow rate. This study has reference significance for the optimization design of the hybrid laminar wing shape and suction strategy. © 2022 AAAS Press of Chinese Society of Aeronautics and Astronautics. All rights reserved.