超声速飞行器近场声爆信号反演技术

Supersonic civil aircraft is an important development direction of the aviation industry; its unique sonic boom phenomenon is the most significant factor restricting its supersonic flight over land. The inverse design of the aerodynamic shape of supersonic aircraft is an effective way to suppress the sonic boom. In order to get more accurate design results, the inverse design based on equivalent area distribution needs the direct guidance of far-field perceived sound pressure level. For this reason, methods combining reverse propagation with POD and adjoint equation gradient optimization are proposed to inverse the near-field sonic boom signals from the far-field ones. We use the standard model LM1021 provided by SBPW for calculation. The accuracy is evaluated from far-field sonic boom signals’ sound pressure and loudness levels in the frequency domain. The results show that POD optimization and adjoint equation gradient optimization based on the reverse propagation results can obtain a more accurate near-field overpressure signal for an arbitrary far-field sonic boom signal. Of these two methods, the adjoint equation inversion method has a better inversion ability for high-frequency shock signals, yielding more accurate far-field sound pressure levels. Furthermore, the equivalent area distribution is highly consistent with the reference value. This method can provide a solid basis for the aerodynamic optimization design of low sonic explosion guided by equivalent area.