| dc.description.abstract | This study employs the Discrete Element Method (DEM) to simulate the flow and mechanical behavior of granular materials impacting two types of obstacles in a chute: wedge-shaped obstacles and cylindrical obstacles. The study explores the effects of these obstacles on the transport properties and internal characteristics of the granular flow in the chute. The analysis includes the flow depth, flow velocity, granular temperature, as well as the distribution of normal stresses, shear stresses, and stress ratios. Major research findings are summarized below: (1) In the case of wedge-shaped obstacles, the larger the Froude number, the closer the DEM simulation results are to the theoretical analytical solutions; in other words, the greater the chute slope, the closer the results are. In the case of cylindrical obstacles, the smaller the Froude number, the closer the DEM simulation results are to the theoretical analytical solutions, indicating that the smaller the chute slope, the closer the results are; (2) Granular flow impacting the obstacles generates two types of shock waves (Contact and non-contact waves), with the shock wave type being influenced by the chute angle and the half-apex angle of the wedge-shaped obstacle. In the case of cylindrical obstacles, the shock wave type is independent of the chute angle and obstacle diameter, with non-contact waves always being created; (3) Due to the influence of the obstacles, both types of DEM simulations exhibit particle retention phenomena, leading to an increase in flow depth, a decrease in flow velocity, an increase in granular temperature, and higher stress values in front of the obstacles. As the obstacle size increases, the retention phenomena occur earlier; (4) In the case of wedge-shaped obstacles, the upstream average value of σxx/σzz is 1.0, and a maximum stress ratio close to 6.5 is observed in front of the obstacle at a half-apex angle of 25°. In the bottom of the chute, the upstream average value of τ /σzz is approximately 0.36, and a maximum stress ratio close to 0.75 is observed in front of the obstacle at a half-apex angle of 25°. For cylindrical obstacles, similar conclusions apply: the upstream average value of σxx/σzz is 1.0, and a maximum stress ratio close to 4.4 is observed in front of the obstacle at a chute angle of 20°. In the bottom of the chute, the upstream average value of τ /σzz is approximately 0.36, and a maximum stress ratio close to 0.76 is observed in front of the obstacle at a chute angle of 35°. | en_US |