In this paper we present a model to create curved hexahedral and tetrahedral elements for the discretization of mixed structures arising in many engineering disciplines. To this end the recursive domain division is utilized for the generation of triangular and quadrilateral meshes for freeform surfaces. Hexahedral elements are formed by a projection approach which extrudes quadrilateral elements generated on reference surfaces with respect to predefined mathematical rules. The generation of tetrahedral elements is performed by the advancing front algorithm as implemented in Netgen. To make the model computable by finite element software, the Mortar method is employed at the interfaces of the tetrahedral and hexahedral elements. Quasi-regional mapping is applied to represent curved high order solid elements. A series of examples concludes this work.
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