Modeling of Mid-Frequency Reverberation in very Shallow Water.

摘要

The long-term goal of this research is development of computationally efficient physics-based methods for modeling of propagation, scattering, and reverberation in shallow waters with complicated spatial and temporal variability of environmental parameters. Scientific objective of this project is to develop a model of mid frequency reverberation for very shallow water environments. The model is to be relevant to specific conditions (1 10 kHz, approximately 20 m water depth, approximately 5 km range) of the ONR Target and Reverberation experiment performed during the spring of 2013 (TREX13). This will result in developing codes for computer simulations to be used in TREX13 data analysis based on environmental inputs measured or/and typical for the chosen location. The research is to contribute to involving non-traditional approaches to better understand shallow water propagation and reverberation. This would support the idea expressed in the white paper, that a new area of investigation for WPRM (Wave Propagation in Random Media) should be suggested, to be relevant to TREX13 conditions. Particularly, for the chosen mid frequency range and very shallow waters, joint effects of the relatively large bottom penetration and 3D variability of the sediment properties, along with related effects of propagation, 3D refraction, and scattering within the seafloor, should be taken into account. Therefore, an approach is needed that treats heterogeneous stratified sediments as a critical part of the propagation channel (in addition to heterogeneous water column with rough boundaries).