Development of Adaptive Vorticity Confinement Based CFD Methodology for Rotorcraft Applications Navy SBIR FY2013.2 Sol No.: Navy SBIR FY2013.2 Topic No.: N132-092 Topic Title: Development of Adaptive Vorticity Confinement Based CFD Methodology for Rotorcraft Applications Proposal No.: N132-092-0823 Firm: IllinoisRocstar LLC 60 Hazelwood Drive P. O. Box 3001 Champaign, Illinois 61826-3001 Contact: Bono Wasistho Phone: (256) 542-8123 Web Site: www.illinoisrocstar.com Abstract: The accurate representation of the rotor wake, especially the tip vortex structure, in a computationally efficient and algorithmically straight forward way is crucial for prediction of rotor aerodynamic performance, noise emission, and rotor structural dynamics. A promising approach for design and optimization is the vorticity confinement (VC) method that minimizes the numerical diffusion of vorticity in the vortical flow regions. The remaining challenge is to remove the tuning of model parameters to make the method truly predictive and robust. We will develop a fully adaptive VC (AVC) method based on a new formulation. Auxiliary numerical treatments will be implemented that can detect and mitigate potential instabilities, borrowing the idea from shock capturing schemes. We will assess the AVC method in different types of numerical schemes, particularly the spatial discretization scheme. A procedure to determine model parameters dynamically will be constructed dependent on the numerical schemes employed. As a result, it is expected that the new VC methodology will be broadly applicable and characterized for a range of numerical schemes. The Phase II AVC implementation will address rotorcraft applications, including strong transients, rotor noise due to blade vortex interaction, rotor-body nonlinear interactions, and aeroelasticity of the rotor blades. Benefits: This program will provide pathways to two salable products: software and engineering services. Software: A validated tool to accurately predict rotorcraft flow in operating condition in a tractable manner will be available from this work. It will be of commercial quality and based on modeling that is developed from more rigorous theoretical foundation. It will have great modeling flexibility and robustness due to its general adaptive modeling paradigm (no tunable model parameters), possesses inherent stability property, modular, multiphysics module structure, and incorporate state-to-the-art numerical and parallel schemes. All DoD mission agencies have interest in predicting rotorcraft flow phenomena accurately for improvements in rotor design for performance, rotor noise mitigation, and mission planning (e.g. Army, MDA, Navy, Air Force and NASA), and many U.S. industry and government agencies can also benefit from the capabilities of a flexible, validated modeling package. OEMs and prime contractors providing engine technologies will immediately benefit. Engineering services: Analytical and consulting services will be available based on the validated capabilities at the end of Phase II. These services are needed by the DoD components, aircraft manufacturers and their tier two and three suppliers. The Phase III application of this technology will principally address the mission service prime contractors in this space. Return