Comparison of Low-boom Predictions from Different Sonic Boom Propagation Codes

International audienceA comparison of sonic boom propagation codes from NASA and ONERA was conducted using low-boom test cases from the 3rd AIAA Sonic Boom Prediction Workshop. Near-field pressures from two different shaped, low-boom demonstration aircraft concepts had been calculated with computational fluid dynamics codes and were used as starting signatures for the acoustic propagation analyses. In addition, atmospheric profiles from NOAA's Climate Forecast System Reanalysis database, including pressure, temperature, humidity, and winds as a function of altitude, were used to predict sonic booms propagating through realistic atmospheric conditions. The ground waveforms and derived loudness metrics were compared at regular intervals across the sonic boom carpet and at the location of the lateral cut-off rays. This code comparison exercise and investigation into the possible causes of differences enables a verification of the codes and proposed recommendations for code refinement