Numerical Evaluation of Effect of Atmospheric Turbulence on Sonic Boom Observed in D-SEND#2 Flight Test

摘要

Some numeical analyses results for predicting the effect of atmospheric turbulence on sonic boom, especially for the waveform observed in the second phase of the D-SEND(Drop test for Simplified Evaluation of Non-symmetrically Distributed sonic boom) flight test, are presented in this paper. The target waveform, which should have a property of low-boom waveform, took the shape with a much gentler curve than the designed one. Through some inspections of the flight test, it was found that the effect of atmospheric turbulence had a possibility to give a reasonable explanation of such a deformation of waveform. This paper therefore shows its evidence in detail and, in addition, distinctive characteristics of the nature of low-boom waveform compared with conventional N wave is also discussed.