Numerical Simulation of Gravity Current Descending a Slope into a Linearly Stratified Environment

Abstract

AbstractThe accurate prediction of the dilution and motion of the produced denser water (e.g., discharge of concentrated brine generated during solution mining and desalination) is of importance for environmental protection. Boundary conditions and ambient stratification can significantly affect the dilution and motion of gravity currents. In this study, a multiphase model was applied to simulate the gravity current descending a slope into a linearly stratified ambient. The k-ω turbulence model was used to better simulate the near-bed motion. The mathematical model, the initial and boundary conditions, and the details of the numerical scheme are described here. The time-dependent evolution of the gravity current, the flow thickness, and the velocity and density field were simulated for a range of flow parameters. Simulations show that the Kelvin–Helmholtz (K-H) billows are generated at the top of the trailing fluid by the interfacial velocity shear. The K-H instability becomes weaker with the slope distan...