Abstract:
The permeable submerged dam is a new rectification building that takes into account both the ecology and the environment. In order to understand thoroughly the flow characteristics near the permeable submersible dam, based on the N-S equations and the theory of incompressible gas-liquid two-phase flow, a three-dimensional numerical model was developed to numerically simulate the flow characteristics near a trapezoidal permeable submerged dam. The influence of penetration rate, water depth and velocity on the flow characteristics, turbulent kinetic energy and vorticity flow around submerged dams was studied. The results show that under the same flow conditions, with the increase of the permeability, the reverse flow velocity decreases and the turbulent intensity of the root of the dam increases gradually, while the turbulence intensity decreases gradually in the range of 1~4 times the height of the dam, and the vorticity increases firstly and then decreases. Under the same permeability, with the condition of the average flow velocity at the same cross section, the seepage flow rate gradually decreases as the water depth increases, the turbulence intensity near the submerged dam decreases as a whole, but the variation of the turbulent range is not large, and the area of the strong vorticity area of the dam is also reduced. Under the same water depth condition, with the increase of the average flow velocity of the section, the vortex reflow intensity increases gradually, and the turbulence intensity around the submerged dam also increases, positive and negative vortices are staggered and distributed between the top side of the dam body and the pervious round hole, and the vortices strength gradually increases.