3-D Simulation of Sedimentation in Turbidity Currents

The gravity currents on the inclined boundaries are formed when the inflow fluid has a density difference with the ambient fluid and a tangential component of gravity becomes the driving force. If the density difference arises from the suspended particles, the currents are known as particle-laden density currents, or turbidity currents in which the local density depends on the concentration of particles. A low Reynolds k- ε turbulent model is used to simulate three dimensional turbidity currents. Also some laboratory tests were conducted to study the 3D flow resulting from the release of particle laden density currents on a sloping surface in a channel of freshwater via a sluice gate. Kaolin was used as the suspended material. The height, width, velocity and concentration profiles of turbidity currents were calculated and compared with the experimental data and showed good agreement. Different settling velocity formulas based on, first, solitary particle and, second, considering the effect of dispersed particles thorough the fluid are exerted in the concentration equation and the results compare with each other. Also the sedimentation heights of the turbidity current are simulated which are compatible with the experimental data.

کلیدواژه ها:

Turbidity Currents ، 3-Dimensional flow ، Low Reynolds number models