This SBIR Phase I proposal will examine the feasibility of using the VorCat implementation of the gridfree vortex method to provide accurate, real time simulations of rotor wake, specifically the tip vortex structure, in various flight scenarios. Rotor wake flow is complex and poorly served by traditional Computational Fluid Dynamics (CFD) methodologies due to their inherent excessive numerical diffusion and this project capitalizes on the unique capabilities of the VorCat code in efficiently capturing the physics of complex turbulent flows by using vortical elements to represent the vortices that lie at the heart of turbulent fluid motion. The phase I study will be aimed at answering several questions that will establish the parameters controlling real time wake vortex dynamics and consequently in what way rotor downwash affects rotor aerodynamics and structural loading. In particular, this study will investigate several approaches for modeling rotor vorticity and will establish the optimal setup that provides rapid and accurate results. This, in turn, will be utilized for a rigorous analysis which will determine the flow parameters that dominate wake vortex dynamics. If successful, the technology will be verified, validated and delivered to the Navy in later phases of this work.
