Analysis, Design & Test of Low Reynolds Number Rotors and Propellers

Unmanned air vehicles (UAVs) have no design limitations that are characteristic of manned flight. As a result, very small UAVs are being designed. The aerodynamics of very small vehicles places them in a low Reynolds number range, the physics of which is poorly understood. In the case of rotorcraft and propellers, assumptions that are made at higher Reynolds numbers, such as being able to idealize the flow over the airfoil as two-dimensional and steady, are invalid. The project has two main efforts: a computational effort to develop a model of low-Reynolds-number flow, and an experimental effort to obtain aerodynamic data on 2-D and 3-D wings and a rotor configuration. The computational effort will focus on the modeling of separation bubbles common to low Reynolds number flight. This involves modeling laminar separation and turbulent reattachment. The main approach will be the application of vorticity confinement methodologies pioneered by Flow Analysis.