Propagation of sonic booms through the atmosphere

Abstract

During the past 20 years the authors have been involved in developing physically based prediction calculations for sonic booms and other nonlinear atmospheric waves. Early work developed a calculation method for the effects of atmospheric absorption and dispersion on sonic booms in a quiescent atmosphere. The validity of this method has been confirmed by recent collaborative work with the University of Texas [J. Acoust. Soc. Am. 100, 3017–3027 (1996)]. More recently, the authors have been working on a method of predicting the effect of turbulence on sonic boom waveforms in the planetary boundary layer. A Monte Carlo approach has been employed so that histograms of measured variables which are needed for environmental assessment can be developed, rather than a single average value [J. Acoust. Soc. Am. 99, 147–152 (1996)]. This prediction method can be combined with the earlier sonic boom propagation algorithm to predict the ensemble of received waveforms at the ground, given the waveform in the vicinity of the aircraft, based solely on physical considerations.