Numerical simulation of the effect of the radial gradient of the suspension plate on the characteristics of the sediment discharge funnel flow field based on large eddy simulation
To understand the effect of changing the radial gradient of the suspension plate on the flow field in the sediment discharge funnel, the vortex funnel water with the slope of i=0, 0.083, 0.173, and 0.259 was calculated by combining the large eddy simulation and VOF methods. The three-dimensional flow field of gas two-phase flow was numerically simulated, and the discrete phase particle trajectory model (DPM) was used to simulate the cut-off rate of particle size of 0.001mm~0.1mm particle size by the sand funnel at different radial slopes. The simulation results showed that the tangential flow velocity increased first, then decreased or tends to be constant as the radial gradient increases, indicating that the indoor vortex intensity does not increase monotonically with the radial gradient of the suspension plate, and there is a critical gradient. The eddy current intensity in the room was maximized; when slope i=0.173, the radial and vertical combined velocity in the upper region of the suspension plate (except for the overflow surface) is parallel to the radial slope of the suspension plate and points to the center of the funnel. The sediment was transported to the hopper chamber again and it was not easy to flow out with the overflow stream, reducing the probability that the sediment will enter the downstream and the sediment will fall on the suspension. The simulation results of the particle rejection rate also showed that the funnel has the largest cut-off rate for the particle size at each stage when i=0.173, and it also indicated that there is a critical value for the radial slope of the suspending plate, so that the funnel cut-off rate reaches a maximum value.