Accession Number : AD0766425

Title :   Propagation of Internal Gravity Waves in a Medium of Weak Random Vertical Shear.

Descriptive Note : Environmental research papers,

Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS

Personal Author(s) : Forbes,Jeffrey M.

Report Date : 21 JUN 1973

Pagination or Media Count : 24

Abstract : The dispersion relation is derived for the ensemble-averaged wave in a Boussinesq fluid with a weak random vertical shear. The basic flow is assumed to be statistically homogeneous in space and time with zero mean. The phase velocity and decay rate are found for the two limiting cases where the wavelength is much greater and much smaller than the correlation length of the basic flow speeds. The decay rate is found to increase as the direction of propagation becomes more horizontal. However, the maximum decrease in phase velocity is found to occur when the wave is propagating at an angle of 50 degrees to the horizontal. These results are compared to those previously published (Keller and Veronis, 1969) for the analagous problem of Rossby waves propagating in the presence of random zonal currents that vary with latitude. (Author)

Descriptors :   (*FLUID MECHANICS, WAVE PROPAGATION), DISPERSION RELATIONS, EQUATIONS OF MOTION, APPROXIMATION(MATHEMATICS)

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE