LOCALIZATION OF SOUND PRESSURE LEVEL INCREASES IN UPWIND DIRECTION WITH RESPECT TO AIRCRAFT NOISE

Abstract

Under certain conditions, it is important to consider real atmospheric effects in aircraft noise prediction models. This paper presents a step toward a simulation framework that can be used to calculate airport noise scenarios more accurately by taking atmospheric factors into account. This work deals with the phenomenon of increased sound pressure levels in the upwind direction from aircraft during take-offs encountering crosswind. In the upwind domain, an acoustic shadow zone is formed, however, certain atmospheric conditions can increase the sound pressure level by more than +7 dB in a limited spatial range. Influencing factors are the altitude of the aircraft and logarithmic vertical gradients in the speed of sound