Numerical Simulation of Gravity Current Front

Abstract

The present study investigates the dynamics of gravity current fronts experimentally and theoretically. Two typical fronts of gravity currents on the inclined boundaries are considered. One is the front of inclined plumes in which the negative buoyancy flux is continuously supplied from the upstream of the front. The other is the front of inclined thermals in which no negative buoyancy is supplied from the upstream. The simulation models are presented for two types of gravity current fronts. The models consist of the conservation equations of mass and buoyancy and the momentum equation for the gravity current front. The frontal shape, the entrainment rate of ambient fluid, and the shear stresses acting on the upper and the lower boundaries, etc., are described as the constitutive relations. The experiments on inclined plumes and inclined thermals using saline water are carried out. The experimental results are compared to the numerical simulation models. Both numerical models can simulate the dynamics of gravity current fronts, i.e., the fronts of inclined plumes and inclined thermals.