Adaptive Meshing Techniques for Viscous Flow Calculations on Mixed Element Unstructured Meshes

An adaptive refinenlenl, strategy based on hierarchical elelnellt sul_division is formulat.ed and iml)h'nwt+ted for meshes containing arl)ilrarv nlixlltres o[ t.et.rahedra, hexahedra. 1)risms and pyramids. Special at.tentiot_ is given to keepitlg metnorv overheads as low as possible. This pt'ocedure is coupled with an algel)raic multigrid flow solver which ol)erales on mixedelement meshes. Inviscid flows as well as viscous flows are computed on adaptively refined tet.rahedral, hexahedral, and hybrid meshes. Theel[icietwvoftlle melhod is detnonstrated I)y genet'ating a.ll adal>ted ltexa.hedral mesh containing :_ milliot+ vertices on a t'elativelv inexpet>ive workstation. This research was supported by the Nat, ional Aeronautics and Space Administration under NASA Cot> t, ract. No. NAS1-19480 while the author was in residence at, the Institute for (lOtnl)uter Applications in Science and Engineering (I('ASE), NASA Langley Ftesearch (:ent.er, |tatnpton, VA 2:_681-0001.