超声速民机机动飞行的聚焦声爆全场预测方法研究

Supersonic civil aircraft will produce intense focused sonic booms during maneuvering flight phases such as acceleration and dive. The full-field prediction method for this is one of the current research hotspots and difficulties internationally. As the cost brought by the full-domain unsteady calculation is currently unaffordable,the full-field prediction of focused sonic booms is divided into caustic calculation and waveform prediction,and the ground focusing position and sonic boom intensity are obtained through iterative solution between the two parts. Firstly,by coupling the solutions of the maneuvering flight trajectory and the propagation path of sound rays,two types of caustic calculation methods,namely the iterative intersection point method and the forward envelope line calculation method,have been developed. Secondly,the incident waveform is iteratively obtained between the caustic calculation and the near-field calculation plus the middle/far-field propagation,which serves as the input for solving the lossy nonlinear Tricomi equation. A set of full-field prediction methods for focused sonic booms has been developed,and an independent prediction program “FC-Boom” has also been developed. Finally,the correctness of the full-field prediction method and the program is verified by using the benchmark example of the Third AIAA Sonic Boom Prediction Workshop and the flight test example of the US SCAMP project. This work can serve as the basis for the suppression of focused sonic booms and the design of low-focused sonic booms.