The morphing trailing-edge wing optimization design of the civil aircraft

Abstract

The research on the aerodynamic optimization design of applying the continuous trailing-edge variable camber wing to the civil aircraft is presented, and the necessity of considering pitch moment trimming in the optimization design is explored. The free-form deform (FFD) technique is used to accomplish the parameterization of the wing shape, the trailing-edge camber and the rotation of the horizontal tail. The discrete adjoint technique based on RANS (Reynolds Averaged Navier-Stokes) equations is used to solve the gradients of aerodynamic coefficients with regard to design variables, and the sequential quadratic programming is used to carry the gradient-based optimization design. Based on the common research model (CRM), a single target optimization with constraints is carried to reduce the aerodynamic drag, and the feasibility of the optimization system is confirmed. Then, in different cruise lift coefficients, the trailing-edge variable camber wing optimizations are carried with and without moment trimming respectively. The optimization results show that by trailing-edge morphing, the spanwise lift coefficient distribution is improved and the wave strength is reduced; in order to achieve the optimized design result, it is a necessity to consider the moment trimming constraint.