Long-range sound propagation modeling with the Semi-AnalyticFinite-Element method

The prediction of long-range outdoor sound propagation has gained increasing relevance in recent years due to the low-frequency noise generated by renewable energy converters and the monitoring and localization of violent natural and human-made events. In this study, we present a numerical scheme based on the semi-analytic finite element (SAFE) method for modeling long-range sound propagation. The model computes the sound field using a compact basis of acoustic atmospheric modes, making it particularly efficient for predicting fields in the downwind direction under downward-refracting atmospheric conditions. We compare the SAFE solutions to high-resolution numerical results obtained from the linearized Euler equations (LEE) and demonstrate both qualitative and quantitative agreement. For large, range-independent domains, the SAFE method proves to be accurate and significantly more efficient than direct numerical LEE computations.