ENTRAINMENT IN 3-D DENSITY CURRENTS

摘要

A CFD code has been developed to describe the salt solution density current, which propagates three-dimensionally in deep ambient water. The height and width of the dense layer are two dominated length scales in 3-D structure of density current. In the experimental efforts, it is common to measure the height and width of this current via its brightness. Though, there are analytical relations to calculate the current height in two-dimensional flow. But, these relations can't be used to identify the width and height of 3-D density current due to the existence of two unknown parameters. In the present model, the height and width of the dense layer are obtained by using the boundary layer concept and the results show this concept can be a useful idea to identify the height and width of 3-D density current. The entrainment coefficient was also calculated by using the depth-averaged parameters and compared with the experimental data. Result has the same trend as Ellison and Turner experiments.