Influence of Atmospheric Conditions on Sound Propagation - Mathematical Modeling

Propagation of sound in atmosphere is influenced by many factors such as air temperature, relative humidity, air velocity and direction as well as temperature inversion. Intensity of sound disappears in depending on distance by atmospheric absorption and atmospheric turbulence. Many times it is difficult and sometimes impossible to determine the values of equivalent sound pressure levels (A) under different atmospheric conditions. To identifying changes caused by atmospheric conditions is preferred to use the programs for mathematical modeling. The differences of measured values of equivalent sound pressure levels (A) under various atmospheric conditions are not insignificant. When comparing favorable and unfavorable atmospheric conditions for propagation of sound, difference of values of equivalent sound pressure levels (A) may be up to 10 dB. Obviously under conditions that are placed on these measurements like relative humidity <95 % and air velocity <3 m.s -1 . This article aims modeling the impacts of different atmospheric conditions with use the software Cadna A, which is used to mathematical modeling of exterior noise maps.