On the Application of Hybrid RANS-LES and Proper Orthogonal Decomposition Techniques to Control of Cavity Flows
Abstract
Issues pertaining to the application of hybrid RANS-LES modeling and Proper Orthogonal Decomposition (POD) techniques to the development of control strategies for cavity flows are discussed. The criteria for correct and consistent hybrid RANS-LES modeling are outlined - unsteady RANS-LES interfacing and mesh sensitive eddy-viscosity modeling are identified as the main issues. Preliminary calculations of a compression ramp are presented to illustrate our approach for RANS-LES interfacing. Next, a generalized mesh dependent eddy-viscosity modeling procedure is detailed and its applicability is demonstrated through calculations of weapons bay cavity flows. Comparisons with measurements are seen to agree better than earlier "LES" calculations which did not adequately treat the approach boundary layer. The technique is then used to create datasets for developing a POD based model of the cavity flow field. The differences between coupled and uncoupled POD applications to the density and velocity fields are discussed - it is seen that the coupled approach yields a flow field representation that is closer to the parent LES flow field than the uncoupled approach. Finally, a dynamical systems model of the flow field is presented. Applications to control problems are now in progress and will be presented in the future.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2001
- Accession Number
- ADP013689
Entities
People
- Lawrence S Ukeiley
- Neeraj Sinha
- Srinivasan Arunajatesan