Grid independence via automated unstructured adaptive remeshing.

摘要

Grid independence is frequently an overlooked item in Computational Fluid Dynamics (CFD) analyses. Results obtained from grid dependent solutions may prove to be costly, in that engineering design decisions can be made using potentially faulty information. Therefore, grid independence should be viewed as an extremely important element of any CFD analysis. An automated method for grid independence is developed for two dimensional unstructured wall function grids. Grid independence is achieved via successive levels of adaptive remeshing. Adaptive remeshing is performed in an automated manner and is based upon normalized undivided differences in field variables. Sensors are placed at strategic locations within the flow-field, which are determined by querying the CFD solution of a uniform grid. Four classes of problems are examined, flow over an asymmetric transonic airfoil, the backward facing step, diffusion flame combustion and the synthetic jet. Grid independent solutions are obtained for all four classes of problems. Results for each case compare reasonably well with experimental data and/or other numerical predictions.