Rapid hypersonic sonic boom prediction using line-distributed energy impulse formulations with and without lift effects

Due to the growing interest in the design of low-boom hypersonic aircrafts, there is an urgent need for a theoretical sonic-boom prediction tool that is much cheaper than flight/shock-tunnel experiments and much faster than computational fluid dynamics (CFD). In this paper, we develop a novel hypersonic sonic boom theory that addresses this need. Specifically, a semi-analytic prediction tool based on a line-distributed energy impulse formulation, leveraging Newtonian aerodynamics for force distribution calculation, is developed for scenarios with and without lift. Since the process of solving detailed governing equations is circumvented using such a method, the algorithm was found to be much faster than CFD, with turnaround times in the order of a few minutes. The formulation was validated against CFD results with an error ∼ 10% by various scenarios with and without lift. Geometries used for validation include a sphere, a nosed cone, a nosed elliptic cone (the first sector of HIFiRE-5), and a boost-glide vehicle (BGV). The lift (or lack thereof) is achieved by varying the angle of attack. The formulation is also validated against wave propagation data (with CFD data as the input) for the middle and far fields, within acceptable errors. Azimuthal angle dependence (i.e., sonic boom carpet effect) and stratified atmosphere effect are also discussed.