Development and Testing of a Low Cost CFD Based Analysis for Surface Mesh Interrogation Refinement for Applied Aerodynamics Applications

摘要

Accurate flow calculation is crucial to the development and analysis of air platforms, missiles and operations support. Computational Fluid Dynamics (CFD) has demonstrated much success in predicting aerodynamic performance for a wide variety of flow conditions; however, reliable CFD requires extensive, time consuming, CAD cleanup and surface grid generation and refinement efforts prior to volumetric grid generation and convergence studies. Moreover, such studies are time consuming, computationally expensive and are not always robust. For many real-world applied aerodynamics applications this process is particularly expensive, or even intractable, due to geometric complexity; use of legacy, or dirty, CAD; inadequate, surface grids; and the need for predictions in shortened times. This paper documents a recently completed effort for the U.S. Army to directly address these issues for real-world applied aerodynamics applications by developing a low cost CFD-based pre-processing tool suite to guide the creation of suitably refined CFD grids for routine production calculations. The software is based upon a surface mesh analysis program and a novel robust cut-cell Cartesian grid CFD method that outputs guidance on local surface mesh corrections and refinement/de-refinement based on both surface topology and volumetric flow requirements. This paper describes the development and validation of this toolset and demonstrates the potential of the tool to address the needs of CFD practitioners.