Euler方程式と拡張Burgers方程式に基づく前進翼平面形におけるソニックブーム強度の数値的調査

抄録

The purpose of this study is to validate the utility of a forward-swept wing in significant reducing the acoustic level of the sonic boom during a supersonic cruise. This was achieved by investigating the aerodynamic performance of wings with different leading edge angles. A total of 13 wing-body-engine nacelle configurations were defined with varying outer wing planforms for a supersonic business jet model. The resulting aerodynamic drag was evaluated using the three-dimensional compressible Euler equation, and the acoustic level of the sonic boom was evaluated using the augmented Burgers equation. The calculated results for supersonic cruise conditions indicated that the maximum acoustic level of the sonic boom of a forward-swept wing was approximately 4.8 PLdB lower than that of the original backward-swept wing. Furthermore, a forward-swept wing reduced the aerodynamic drag as effectively as a backward-swept wing during supersonic cruising. The sonic boom signature at the ground level indicated that forward-sweeping of the wing caused obvious multi-peaks on the bottom peak of the trailing sonic boom, which demonstrated that the forward-swept wing could reduce the intensity of trailing sonic boom.