Low Reynolds Number, High-Lift Airfoil Design for VTOL UAVs

A complementary theoretical and experimental effort to design and verify high-lift, low pitching-moment airfoils for VTOL UAVs is proposed. In Phase I, an accurate, rapid, test capability is being validated over the range of Reynolds numbers from 50,000 to 500,000 by investigating the E 387 airfoil, the low Reynolds number calibration standard, in The Pennsylvania State University Low-Speed, Low-Turbulence Wind Tunnel. The section characteristics measured with transition free and fixed will be compared with results from other low-turbulence wind tunnels and with predictions from the Eppler and MSES codes. In Phase II, 10 airfoils tailored specifically to VTOL UAVs will be designed theoretically and five verified experimentally. The design specifications will be developed in cooperation with U.S. Army personnel. The slotted, natural-laminar-flow (SNLF) airfoil concept will be adapted to VTOL UAVs. The experimental results will be used to refine existing airfoil design and analysis methods and to validate CFD codes. Reports on the airfoils will be provided as soon after the design or testing as practicable. The airfoils and their measured characteristics form the foundation of a catalog of airfoils for UAVs.