Construction of Prism and Hex Layers from Anisotropic Tetrahedra

Abstract

The T-Rex anisotropic mesh algorithm generates tetrahedra that are typically combined after generation into pyramid, prism and hex elements in order to reduce the overall cell count and to improve cell quality via increased minimum angles. Parallel to an effort to improve the anisotropic tet generation techniques has been a continued goal of increasing the degree to which tets are combined into larger elements. This paper primarily details the evolution of this latter effort, from simple prism layer extraction to the combination of anisotropic tets on quad and triangle surfaces into pyramid, prism and hex elements. Results pertaining to milestone cell combination improvements are tabulated, and examples of the current state are presented.