Numerical modeling of environmental noise

Numerical modeling is a powerful tool to analyze outdoor noise propagation. Specific numerical techniques are needed to simulate the behavior of acoustic waves in the external environment. Ray tracing technique and beam tracing technique represent effective numerical methods, which are used in current simulation software. Several attenuation terms are to be considered during propagation, and their calculation deeply affects the accuracy of the modeling. Sources' characterization and dose-effect correlation are further key elements. In spite of these critical aspects, numerical modeling effectively applies to a number of different situation (roads, railways, airports, harbors, industries) in which noise pollution must be analyzed, predicted or reduced.