An efficient computational model for wave refraction and diffraction using finite differences

A new type of computational wave transformation model is described in this report. The model incorporates the processes of wave refraction and diffraction, and uses a time-independent finite-difference marching technique. The model is computationally more efficient than most alternative techniques which combine refraction and diffraction in a general manner. Test are carried out on a circular shoal depth profile, a situation for which strong diffraction effects occur.