Numerial Simulation Of Soild-liquid Two-phase Flow In The Gill-Piece Separation Device

The vertical-component density mixture flow separation device (VCDM) is a clean, efficient and low cost of water and sediment separation device.Based on a lot of assumptions, Preliminary research had Optimized the structure of VCDM through changed Geometric and operating parameters in experiments.The limitation of this conventional method is more and more evidentIn order to overcome the limitations of the preliminary research, the author simulated in VCDM solid-liquid two-phase flow using a numerical method (FLUENT). The main conclusions are as follows:(1) There have three exists two density flow that Water and sediment around the gills slice and containers edge of debir filed between two gills slice and in VCDM. Gills slice up and down have clockwise whirlpools each other. The velocity is larger in the side channels and gills slice fluctuation surface,but the rest area is very small.(2) Concentration distribution in VCDM:The concentration of the gills slice upper surface is bigger,mainly for sediment;the concentration of the gills slice nether surface is lower,mainly for water. In the settlement process,concentration gradient change:the upper concentration gradually decrease, the bottom concentration gradually increase. When precipitation ended,concentration gradually increase from top to bottom in VCDM. There are four district and two interface:water area, flocculation area, into layer precipitation area and sedimentation compression area; water and sediment boundary surface and compression interface.(3) Without access flow of VCDM, the laminar model's velocity field and concentration field more similar to the actual flow field.So the laminar model more suitable for the flow numerical simulation.(4) Compared with the single gills slice and five gills slice, get the following conclusion:Five gills slice have obvious advantage. Increase the number of the gills slice can the subsiding speed, improve the separation efficiency, to create favorable conditions for settlement.(5) Using mathematical model is correct and the numerical calculation method is reliable.(6) The author deduced the velocity equation on the gills slices, and verified internal flow stability.