This work presents two and three-dimensional CFD simulations of a discontinuous density current. The numerical results are compared to experimental observations, with good qualitative and quantitative agreement. The three-dimensional simulations proved to be more realistic than the two-dimensional ones, showing that three-dimensional vortex breakdown in the body and tail of the density current plays a significant role in the flow dynamics.
The CFD simulations were carried out using a stabilized equal-order finite element method, in which a discontinuity-capturing technique was embedded for the salt transport. This technique captures sharp fronts with little spurious oscillations, allowing local features such as shear instabilities at density interfaces to be well reproduced.