Drag of an Elliptical Intruder in a Two-Dimensional Granular Environment
摘要
The drag of an elliptic intruder in a two-dimensional granular environment is numerically studied. The movement parallel to the major axis of the intruder is found to be unstable. The drag law is given by the sum of the yield force and the dynamic term, the latter of which is approximately reproduced by a simple collision model. The flow field around the intruder for a sufficiently large drag force is well fitted by the streamlines obtained from the perfect fluid. The stress fields around the intruder are also investigated when the intruder’s movement is balanced with interactions with the surrounding particles. The Airy stress function is found to reproduce the stress fields well once the stress on the surface of the intruder is given.