Planform dependency of optimum cross-sectional geometric distributions for supersonic wing

Abstract

The difference in the supersonic aerodynamic characteristic of different wing planforms is evaluated to determine the optimum parameters for the cross-sectional geometry of a supersonic wing. The supersonic performance of wing with integrated engine intakes was evaluated for a quadruple-tapered wing with a large sweep angle and for a single-tapered wing with a small sweep angle. To reduce the required computation time, the design problems were solved using a multi-fidelity approach consisting of a hybrid surrogate model assisted by evolutionary computation. To evaluate aerodynamic performance, the compressible Euler equation and the linearized compressible potential equation were employed as high- and low-level fidelity solvers, respectively. Through design optimizations, the contributions of different cross-sectional parameters to drag reduction were determined. It was found that the shape of the forward camber and the twist angle around the middle of the wing had the most noteworthy influence on the drag reduction for both wing planforms, because most of the aerodynamic force was generated near the wing mid-span. For a wing with a large sweep angle, a cross-sectional geometry involving a small positive camber at the leading edge, and a small twisted angle was optimum. For a wing with a small sweep angle, a cross-sectional geometry involving a negative camber at the leading edge, and a thinner leading edge, and higher twisted angle than those for a large swept-back wing was optimum because of the ready generation of a shock wave at the leading edge.