Numerical Calculation of Dispersion Relations for Internal Gravity Waves.

摘要

Numerical procedures have been developed to calculate the frequency/wave number dispersion relations for internal gravity waves in arbitrary density gradients. The basic properties of the differential equation governing these waves have been considered in developing these procedures. These procedures have been used to develop a set of Fortran subroutines capable of computing,printing in tabular form,and producing line printer plots of the dispersion relations. Source listings of these subroutines and full descriptions of their use are given. To illustrate the accuracy of the system and to display the results of violating certain restrictions involved in the numerical procedure,an extensive comparison is made between numerical results and an analytic solution for the dispersion relations. The analytical model corresponds to a hypothetical fluid system which closely approximates the average water properties measured during field tests in Bute Inlet,British Columbia, a fjord-type estuary with a density structure characterized by a strong gradient between two nearly homogeneous layers. (Author)