Hyperelastic springback technique for construction of prismatic mesh layers

We consider an algorithm for construction of thick prismatic mesh layers which works as follows. A triangular surface mesh is specified as input. Then, thin initial layer of highly compressed hyperelastic material glued to the surface is constructed using robust algorithm for computation of discrete normals. This pre-stressed material expands, possibly with self-penetration and extrusion to exterior of computational domain. Special preconditioned relaxation procedure is proposed based on the solution of stationary springback problem. It is shown that preconditioner can handle very stiff problems related to construction of very thick one-cell-wide layers for rather fine surface meshes. Once an offset prismatic mesh is constructed self-intersections are then eliminated using iterative prism cutting procedure. Next, variational advancing front procedure is applied for refinement and precise orthogonalization of prismatic layer near boundaries. It is guaranteed that the resulting mesh is free from inverted prisms.