Modelling the scattering of interface waves by mines in the surf zone

Interface waves travelling along the seabed/water boundary may provide a means for detecting mines on or buried in the seabed. Interface waves have a vibration field that is concentrated at the seabed and at shallow depths, an easily recognised relationship between different displacement components, and propagation that is unaffected by conditions in the water. The effectiveness of an on-the-seabed device to generate interface waves is an important consideration for the military effectiveness of the detection concept, given that a system may need to be deployed at short notice in a high risk environment, precluding the possibility of burial. In the work reported here, a method has been developed for predicting, within a Finite Element model, the interface wave field generated by a vibrating device placed on the seabed. The method utilises Perfectly Matched Layers to model within the FE model outgoing waves in the elastic and the fluid environments. The method has been applied to assess the effectiveness o...