Development of cartesian based mesh generator with body fitted boundary layers

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2019
Özkan, Merve
In this thesis, the development of a Cartesian based mesh generator with body-fitted boundary layer is presented. The base of the developed mesh generator consists of Cartesian mesh. However, the boundary layer handling is a challenge with Cartesian mesh. Therefore, a body-fitted boundary layer is introduced to the mesh generator by putting a customized open source mesh generator into the main Cartesian based mesh generation. The boundary layer mesh generation part comes from the customized SUMO code, which is an open source code for body-fitted boundary layer mesh. By using the customized open source code, the boundary layer mesh is generated as wedge volume elements which inflate from the triangular surface elements of the geometry. After generating the boundary layer, there is gap between the Cartesian mesh and the boundary layer wedge volume elements. Since there must be a transition to triangular surface to square surface, this transition is supplied with pyramid and tetrahedral volume mesh. Pyramid volume elements are generated at the inner boundary of the Cartesian mesh as a part of the code. Tetrahedral mesh is generated by using an open source code TetGen, which uses Delaunay tetrahedralization. The Cartesian based mesh generator with body-fitted boundary layer is developed in this thesis for less time-consuming and more efficient meshing process.

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Citation Formats
M. Özkan, “Development of cartesian based mesh generator with body fitted boundary layers,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.