Development of Methodology for Moving Body Simulation Based on Computational Fluid Dynamics

For moving body problems with complex geometries, a robust and reliable approach to constructing computational domains is needed. Based upon our extensive engineering experience with overset grid methods, Digital Fusion Solutions, Inc. (DFSI) proposes to implement new and transfer existing technologies to alleviate the challenges facing unstructured overset grids. The techniques to be implemented are: 1) an innovative hole-cutting technique based on the solution of Green’s Function, 2) a general finite-volume flux reconstruction approach for boundary cells, and 3) an optimized, or minimum, overlap algorithm to ensure that the global solution is computed on only the best cells. Unstructured overset methods show great potential for moving body problems particularly in automated grid generation. The current trend is to apply structured overset grid techniques to unstructured grids, where long standing issues related to orphan points, interpolation inaccuracies, and searching inefficiencies are still not adequately addressed. For moving body problems, a generalized overset capability is highly desirable, to avoid methods that require grid stretching, regridding, and interpolation. Under this SBIR we will implement these new techniques for two-dimensional problems using an open-source flow solver. Phase II will extend the methods to three-dimensions, and transfer the technology to the engineering analysis environment.