CHARACTERISTICS OF THE PROPAGATION OF WEAK SHOCK-WAVES IN AN INHOMOGENEOUS ATMOSPHERE

An equation is derived for the vertically upward propagation of a bounded sound beam in a vertically inhomogeneous atmosphere with allowance for nonlinear, dissipative, and diffraction processes. The influence of these processes on the parameters of a weak shock wave is estimated for various heights and a standard atmosphere. In particular, nonlinear processes have a stronger effect on waves having a larger period, which therefore attain greater heights in the atmosphere. The vertical inhomogeneity of the atmosphere significantly offsets wave attenuation. The attenuation does not depend on the amplitude in this case, but is more pronounced for smaller periods, and this fact together with nonlinearity determines the fluctuating properties of the atmosphere. Diffraction processes provide a definite contribution only in the initial stage of wave propagation and are therefore insignificant in the determination of the threshold at which a weak shock wave degenerates into sound waves. The theoretical conclusions are corroborated by generalized experimental results from 15 explosions.