Investigation of flow rate in a quasi-2D hopper with two symmetric outlets

In this study the flow rate in a quasi-2D hopper with two symmetric outlets was investigated numerically. When two outlets merge into one, the flow rate is obviously bigger than that with a large enough distance between them. To explain the influence of the interaction between these two outlets, it was found that the velocity field above one outlet will be affected by the neighboring outlet by reducing the stagnant zone. With increasing distance, this interaction becomes weaker. Finally the formula of flow rate considering various outlet sizes and distances is fitted to the simulation data.