A structured grid based solution-adaptive technique for complex separated flows

摘要

A structured grid based technique is presented to enhance the predictive capability of widely used CFD codes through the use of solution-adaptive gridding. The procedure redistributes mesh points based upon an existing flowfield. A newly developed weight function employing Boolean sums is utilized to represent the local truncation error. This weight function is then used to construct forcing functions associated with an elliptic system. A NURBS representation is employed to define block surfaces for boundary point redistribution. The technique has been applied to a flowfield about a configuration of practical interest. This flowfield involves supersonic freestream conditions at angle of attack, and exhibits large scale separated vortical flow, vortex-vortex and vortex-surface interactions, separated shear layers and multiple shocks of different intensity. The results demonstrate the capability of the developed weight function to detect shocks of differing strengths, primary and secondary vortices, and shear layers adequately.