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A method for representing structural boundaries by mathematical equations and triangle meshes in DEM simulations

The representation of structural boundaries is of significant importance for the applications of the discrete element method in an industry. In recent decades, triangle meshes are extensively used for representing structural boundaries. Structural boundaries of industrial objects are composed by regular shapes and irregular shapes in many occasions. A method for representing structural boundaries with regular shapes and irregular shapes has been developed by combining mathematical equations and triangle meshes for computational efficiency. When structural boundaries are represented by mathematical equations and triangle meshes, gaps or protuberances may exist at the connection boundaries between regular shapes and irregular shapes. For the exactness of representation of structural boundaries, gaps or protuberances are identified, expressed and treated successively, so that the geometrical shapes composed by regular shapes described with mathematical equations and irregular shapes described with triangle meshes can replace the original structural shapes. Two series of numerical tests have been conducted to verify this method. The results showed that this method can effectively represent complicated structural boundaries containing regular shapes and irregular shapes and greatly reduce computational cost in the contact detection between particles and structural boundaries. Copyright © 2016 John Wiley & Sons, Ltd.