Flows generated by density differences are called gravity or density currents which are generic features of many environmental flows. These currents are classified as the conservative and non-conservative flows whether the buoyancy flux is conserved or changed respectively. In this paper, a low Reynolds k-ε turbulence model is used to simulate three dimensional density and turbidity currents. Also, a series of experiments were conducted in a straight channel to study the characteristics of the non-conservative density current. In experiments, Kaolin was used as the suspended material. Comparisons are made between conservative and non-conservative's height, concentration and velocity profiles of the current and their variations along the transverse intersections. Outcomes indicate that the presence of the particles influences the flow structure sensibly. The results are compared with the experiments and showed a good agreement.

Volume Subject Area:
Fluids Engineering
Topics:
Density, Simulation, Flow (Dynamics), Currents, Buoyancy, Gravity (Force), Kaolin, Particulate matter, Performance, Turbulence
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