This picture is 10 injections' particle track after 15000 steps' calculation.nAs shown as the picture, the outlets don't have screen.nThere are 2 velocity-inlets and 4 pressure-outlets, and the 4 outlets' pressure is 0 Pa.nPerhaps because the outlet haven't enough pressure ? nThis picture is velocity pathlines when calculating convergence before DPM model.nBut after DPM model, the pathlines' picture become so. I don't know what went wrong.nn