Features of sound refraction in the atmosphere in fog

The reflection and refraction of acoustic waves at the air-fog interface are considered. The phase velocity and the coefficient of sound damping for fog, as well as the reflection and refraction coefficients at normal and oblique incidences of a wave, are calculated. A dependence of the refraction angle on a frequency and the angle of acoustic wave incidence on the air-mist interface is studied. Based on the analytical expressions obtained and the analysis of numerical calculations, it is established that if a wave is incident from fog to the interface there is a critical angle of incidence so that total internal reflection occurs at greater angles. It is shown that the total internal reflection does not occur when a wave is incident from air on the air-fog interface.