Aerodynamic optimization of civil aircraft with wing-mounted engine jet based on adjoint method

Abstract

An engine jet simulation method based on the isentropic relations and sonic formula is developed to study the effect of engine jet on the aircraft exterior flowfield. The engine jet simulation method is integrated into the high-fidelity optimization framework aiming at aerodynamic optimization of the civil aircraft with wing-mounted engine. The 462 wing shape variables and 3 engine position variables of a typical long-range twin-aisle transport aircraft are chosen to investigate the integrated aerodynamic design of aircraft and powered engine. The results show that 2.7% drag reduction is achieved compared to the baseline configuration. The spanwise lift is close to elliptical distribution and the pressure recover is smoothed to weaken shock wave. The high suction peak on the lower wing surface around engine is removed, and the unfavorable coupling between engine and wing is decreased in the optimization process. Given these achievements, the developed method has the potential to be a useful tool in aerodynamic design problems with engine jet, such as the aft-mounted business jet, and the wing-mounted civil aircraft.