Abstract: The existing ore drawing theory fails to accurately describe the flow characteristics of the granular and the shape of release body under complex mining conditions, and there are limitations in the model. Based on the characteristic that the velocity is zero on the moving boundaries, the basic components and empirical formula of the granular moving speed were proposed. Through the calculation of volume flux in any horizontal and vertical direction, the velocity equation of the ideal granular material is derived. Combined with the integral calculation of the amount of holes, the surface equation of the release body is constructed, and it is proved that the equation can accurately describe the parameter change and flow law of the granular motion field, which is in line with the local flow and moving boundary characteristics of the granular body in the actual ore drawing process. The research results have improved the theoretical framework of the ellipsoid−like ore discharge model, providing theoretical support for the analysis of the ore discharge body shape and the optimization of the discharge process in mining operations.