نبذة مختصرة : Shallow waters acoustic propagation has been extensively studied in the last few years. Indeed, its understanding is of strong interest in a wide range of applications, from the impact on marine fauna to the modelling of harbour surveillance systems or sonar performance assessment. The issue is also a hot topic in standardization for the measurement of radiated sound levels from ships, at relatively short ranges. The study of shallow water environments is complex because of the interferences due to sea-floor and sea surface reflections. On the one hand, different methods have already been developed to model the acoustic propagation, the most widespread being rays, normal modes, parabolic equations or wavenumber integration. These methods, based on different assumptions, can be applied to shallow water environments in some cases. On the other hand, an experimental campaign was done off the coasts of Brittany, in France, to measure the propagation between a source and a hydrophone placed at short distance in a shallow water environment. The transfer functions have been measured for a frequency range from 100 Hz to 10 kHz. The aim of this paper is to compare some of the numerical approaches to experimental data in the case of short range propagation. So far, such comparisons cannot easily be found in the literature. The comparison between the simulations and the experimental results shows good agreement in most of cases. A study to check the sensitivity of a range of input parameters such as water depth, water density or sound velocity in the sediment, is proposed using the Monte-Carlo method. Results for that case study show that shallow water acoustic propagation is more sensitive to geometrical parameters than material properties.
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