Horizontal Ray Curvature Effects in Basins, Troughs,and Near Seamounts by Use of Ray Invariants.

摘要

Horizontal curvature of long-range underwater sound rays can be caused by repeated reflection from a sloping or undulating seabed. Ray invariants were used to derive analytical solutions for the horizontal projections of ray paths for many types of basins, troughs, and ridges. In an arbitrary basin (of low bottom slope) containing isovelocity water, the elevation angle of the ray depends only on the ratio of the basin depth at source and receiver and on the initial ray angle. In a basin with rotational symmetry or a trough with constant cross section, the heading of the ray may be determined anywhere from the initial heading, the final heading, and the elevation angle. Rough figures are derived for the geometrical spreading loss and reflection loss at the edge of a basin. (Author)