Proper Orthogonal Decomposition (POD)/Response Surface Methodology (RSM) Methodology for Low Reynolds Number Aerodynamics on Micro Aerial Vehicle (MAV)

摘要

This report was developed under a SBIR contract. The phase I project results in two major accomplishments that will facilitate the follow-on MAV design/analysis procedures. These are: a new computational (CFD) approach in the treatment of the low Reynolds number (low-Re) aerodynamics for airfoils and a proper orthogonal decomposition (POD) technique that is essential in providing a rapid CFD solution retrieval/reconstruction procedure for evaluations of forces, and moments for 3D MAV wings. Our low-Re aerodynamic method is based on Wilcox's transition/turbulence model concept in conjunction with a simple computational procedure using CFL3D for RANS simulation. Our method is found to yield correct locations of transition point, separation bubble and transition lengths for several low-Re airfoils including SD7003, Eppler387, La203a, and L VNIO9A. Other turbulence models were also exploited in that Spalart-Allmaras model was found to be superior in yielding the closest solutions with test data. Quasi-3D RANS simulation was performed using our simple low-Re aerodynamic model to investigate the vortex stretching effect of the laminar separation bubble. Finally, a POD technique is applied to a University of Florida MAV wing planform to demonstrate its reduced-order modeling capability.