In noise mapping of urban areas, road traffic, rail traffic, airports and industrial plants are the main examined sources of annoyance and sleep disturbance. Another category of noise sources should be considered when noise maps of port cities are worked out: the ships. The population can be markedly annoyed by the exposition of noise due to the ships, when the wharfs are placed near urban areas. In order to analyze the outdoor noise propagation from this kind of sources, the airborne noise emitted by a multipurpose ship has been modelled. Since commercial simulators do not usually include modules for ship noise and no specific tool is disposable in software libraries, ship geometry was recreated by the tools provided for other categories of sources, while ship were characterized as a noise sources by means of specific measurements. The model validation was then developed by the comparison between calculated and measured SPL, making different tests because of the complexity of the ship as a noise source. Then the sound field produced by the ship in an urban context was simulated, considering a residential area of a port city. Calculated noise levels indicate a remarkable exposure of the resident population to the port noise.
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