Implementation of an Adaptive Grid Technique in the Finite Element Solution of Viscous Flows

Numerical Grid Generation in Computational Field Simulations, Ed. M. Cross., B. K. Soni, J. F. Thompson, J. Hauser, P. R. Eiseman, Proceedings of the 6th International Conference, held at the University of Greenwich, pp.361-370, July 1998

MESHING
RESEARCH
CORNER

Department of Mechanical and Industrial Engineering, University of Toronto
Toronto, Ontario, Canada M5S 3G8
E-mail: currie@mie.utoronto.ca

Abstract
This paper presents an adaptive grid technique for solving viscous incompress- ible flow problems. An unstructured grid is adapted by employing local cell division as well as unrefinement of transition cells. The process is dynamic and employs an object-oriented approach to construct a hierarchical data structure which maintains cell and node inter-reference at each adaptive level. Element class and node class are developed to map finite element grids, and index point- ers and pointer arrays are used to minimize the storage requirement. The pres- sure oscillation which occurs at high-Re flow gets controlled through numerical investigation conducted with an exact solution which is defined as Kovasznay flow. The scheme is applied to a fluid flow over a cavity at different Reynolds numbers. The results exhibit good accuracy and justify the applicability of the algorithm.