Abstract:
The low-boom design is one of the key technologies for the design of a supersonic civil aircraft. For a low-boom design, one of the key problems is how to choose the appropriate objective, which is associated with the evaluation of low-boom performance. To apply the sonic boom loudness level to low-boom design, this paper introduces the Stevens' loudness method into the existing low-boom optimization design platform for supersonic civil aircraft and uses the Seeb-ALR model as an example. The Stevens' loudness level of the ground boom and the over-pressure value of the near field are selected as the optimization targets, and the cone contour is used as the optimization objective for the low-boom design. The results show that, compared with the original model, the loudness level/near field over-pressure value optimization reduces the maximum over-pressure value by 18.4% and 40.6%, and the ground boom loudness level by 2.2PLdB and 1.4PLdB, respectively. The optimization results verify the applicability of the Stevens' loudness level in the low-sonic design of supersonic civil aircraft, accurately reflecting the impact of boom on ground personnel, which can be used in the low-boom design. Selecting different boom evaluation parameters as the optimization targets, there are large differences between the obtained model optimization contours and the near/far field over-pressure distribution patterns. Compared with the near field over-pressure value optimization, the optimization of boom loudness level can reduce the ground boom loudness more effectively by changing the distribution of over-pressure.