Application of Strand Grid Framework to Complex Rotorcraft Simulations

Abstract

The strand grid approach is a flow solution method where a prismatic-like grid using "strands" is grown to a short distance from the body surface to capture the viscous boundary layer and the rest of the domain is covered using an adaptive Cartesian grid. The approach offers several advantages in terms of nearly automatic grid generation and adaptation, ability to implement fast and efficient flow solvers that use structured data in both the strand and Cartesian grids, and the development of an efficient and highly scalable domain connectivity algorithm. An earlier work by the authors introduced a strand grid solver called mStrand, which will appear in future versions of the HPCMP CREATE TM -AV Helios framework. This paper presents application of mStrand/Helios strand grid framework for complex rotorcraft problems. The test cases presented are the UH-60A high speed forward flight and high altitude stall problems as well as the HART II blade-vortex interaction problem. The results show that the solution obtained using the strand grid framework is as good as that obtained using well-established structured and unstructured solution methodologies.