Sweeping of unstructured meshes over generalized extruded volumes

An algorithm for the discretization of general extrudable volumes into semi-structured meshes is presented in this paper. The set of considered extrudable volumes is limited to volumes formed by two opposite topologically identical and geometrically similar cap surfaces, from which one is identified as the source and the other one as the target surface, and by the set of lateral quad-mappable surfaces. The source cap surface is discretized by an appropriate unstructured surface mesh which is projected onto the target cap surface using an affine mapping defined between the parametric spaces of the cap surfaces. This mapping is established by a least-squares fit of boundary nodes on the target surface. The structured quad meshes on lateral surfaces are obtained by transfinite interpolation. The volume interior nodes used to form inner layer of elements are defined by the mapping derived from a least-squares approximation of all boundary nodes. The obtained mesh is then subjected to a specific two-phase smoothing. The capabilities of the proposed algorithm are demonstrated by several examples.