Discrete element method based on distance potential
LIU Xunnan1，ZHAO Lanhao1，MAO Jia1，XU Dong2
(1. College of Water Conservancy and Hydropower，Hohai University，Nanjing，Jiangsu 210098，China；2. State Key Laboratory of Hydraulic Engineering Simulation and Safety，Tianjin University，Tianjin 300072，China)
Abstract：The discrete element method based on the potential function has many deficiencies. The physical meaning of the potential function is not clear and the contact force calculation is inconsistent with the reality. A novel discrete element method based on the distance potential for the arbitral convex polygonal elements was thus proposed using the new definition of the distance potential function. This method describes the potential function as a normalized distance function between the contact couples. The distance potential function has the physical meaning and gives an accurate measurement for the embedded extent of the contact couples. Furthermore，the tangential vector is redefined and calculated in this approach. This method retains all the merits of the original potential method and remedies the problem in which the contact force calculation is affected by the element form. In addition，the method gets rid of the restrain of the triangular shape completely and can be applied to the arbitrary polygonal elements. It was illustrated with several examples that the method can accurately simulate the motion of the complex discontinuous media.
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2017, Vol. 36 
