Implementation of a sonic boom propagation algorithm with the augmented Burgers equation

Abstract

For the purpose of sonic boom carpet determination for an optimized routing of supersonic aircraft around landmasses, a sonic boom propagation code was implemented at the Institute of Air Transportation Systems. The implementation is based on the well-known augmented Burgers equation for stratified atmospheres and extends the sole geometric ray tracing that has been used at the institute to determine the lateral cutoff distance of sonic booms so far. For the quantification of sonic boom signatures on ground, algorithms for the computation of noise metrices, namely, the perceived level of noise Stevens Mk VII (PL) and the sound exposure level (SEL) with several frequency weightings are also implemented. This work describes the implementation of the sonic boom propagation algorithm and the methods used for loudness calculation briefly. For the evaluation of the implemented code, pre-defined cases from the Third Sonic Boom Prediction Workshop are simulated, and the computed results are compared to the published results of that workshop. The similarities and differences are discussed in detail, such that the general implementation of the propagation code can be verified, whereas potential inaccuracies, especially for the off-track determination, can be detected and quantified.