Numerical simulations of the buoyant flow of heated water discharged from submerged side outfalls in shallow and deep water
Tóm tắt
In this study, a three-dimensional model was used to numerically study the buoyant flow characteristics of heated water discharged from the submerged side outfalls in shallow and deep water. Hydraulic experimental data was used to evaluate the applicability of the model. The simulation results for model verification are in good accordance with experimental results. For shallow waters, the discharge jet is deflected by the river crossflow while forcing the river flow to bend towards the far bank over the depth. The unidirectional flow is dominant all over the depth in they-z cross section. In the case of submerged discharge with shallow water especially, the recirculating zone is the largest in the lowest layer, becoming smaller in the upper layer. As water depth increases, the ambient flow goes over the jet and thus diminishes the blocking effect so that jet bending decreases. Counterclockwise circulation and local eddies form with the increase of depth. Based on the viewpoint of rapid mixing and the dimension of the recirculating zone, submerged discharge appears more efficient than surface discharge.
Tài liệu tham khảo
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