Comparison of Simulated Sonic Boom in Stratified Atmosphere with Flight Test Measurements

Abstract

A method for predicting sonic boom waveforms emanating from a vehicle flying at supersonic speed is presented and compared to flight-test data. The prediction is achieved through three main steps: searching for the position of the sound source along the flight path, predicting the near-field waveform by a combination of computational fluid dynamics simulations on structured and unstructured meshes, and propagating this waveform to the far field by a numerical solver of the augmented Burgers equation. It is shown that this framework successfully predicts sonic boom signatures observed during the large-scale first phase of the drop test for simplified evaluation of the nonsymmetrically distributed sonic boom field test recently conducted by our research group at the Japan Aerospace Exploration Agency for both conventional waves and lower-amplitude flattop waveforms.