Analysis of Density Currents Using the Non-Staggered Grid Fractional Step Method

A new approach for the solution of time-dependent calculations of buoyancy driven currents is presented. The density distribution is not uniform throughout the flow field, however the incompressibility condition and Boussinesq approximation are assumed to be valid because the time variation of density is not significant. This method employs the idea that density variation can be pursued by using markers distributed in the flow field. The analysis based on the finite difference technique with the non-staggered grid fractional step method is used to solve the flow equations written in terms of primitive variables. The physical domain is transformed to a rectangle by means of a numerical mapping technique. The problems analyzed include two-fluid flow in a tank with sloping bottom and colliding density currents. The numerical experiments performed showed that this approach is efficient and robust.