FLOW ANALYSIS OF ACCELERATING TURBIDITY THERMALS

The turbidity thermals are numerically analyzed using the κ-ε turbulence model. The basic equations are discretized by the SIMPLE method. The constants in the κ-ε turbulence model are set to be the standard values. The turbidity thermals are generated as the saline thermals initially. There are five condisions for calculation, i.e. the cases of the four grain size and a case of no sediment. One of these cases shows that turbidity thermal can erode sediments and accelerate in the flow direction. The variations of the travel speed, the maximum height, the maximum concentration and the contours of concentration and velocity vectors of turbidity thermals are obtained and compared with the resullts of the saline thermal. The characteristics of accelerating turbidity thermals are remarkably different from the other cases.