砂面上に立てられた円柱まわりの流れと砂の動きの数値的研究

抄録

The flow around a circular cylinder standing on the sand is computed numerically and the movement of the sand is investigated. The numerical method employed in this study can be derided into three parts: (1) calculation of the air flow around the cylinder using MAC method with a generalized coordinate system; (2) estimation of the sand transfer caused by the flow through the friction; (3) determination of the shape of the ground. Since the computational area is changed due to the step (3), this procedure has to be repeated for the next time step. From this simulation, it is found that the horseshoe vortex scoops out the ground in front of the cylinder and that the wake makes the sand accumulate in the rear region. The dented region becomes deeper as the cylinder leans to the windward.