The Vortex Flap is a new type of mechanically driven high-lift device consisting of a rotating cylinder placed underneath and near the trailing edge of an airfoil. Wind tunnel tests were designed and conducted in the Washington University Low-Speed Wind Tunnel. Wind tunnel tests indicate that the Vortex Flap produces notable lift coefficient increments and increases maximum lift coefficients, particularly for the low Reynolds number range tested. The best configurations of the configurations investigated (not necessarily optimal) produce lift increments of 300-900% at low-to-moderate angles of attack, and increase the maximum lift coefficient on the order of 200%. The large lift increments found, particularly at low angles of attack, underscore the ability to drive the airfoil to high lift coefficients even at low angles of attack, a potentially useful characteristic for certain flight maneuvers. Regions of fairly high L/D (on the order of 10) as well as low L/D performance were identified. The nondimensional cylinder rotation speed was found to be the most important experimental parameter. Methods for correcting wind tunnel data were developed and outlined, and a Response Surface Method was applied to the corrected data for ease of interpretation. Performance comparisons between the Vortex Flap and other trailing-edge high-lift devices are included. To demonstrate the potential of the device, a Navy mission specification for a VTOL ship-borne UAV, currently filled by a rotary-wing aircraft, is analyzed using a hypothetical fixed wing aircraft and the Vortex Flap. It is demonstrated that, under certain reasonable wind-over-deck conditions, such an aircraft could hypothetically fill a VTOL mission.3.1.1 Wind tunnel The tests were conducted in Washington University in St. Louisa#39; Fluid Mechanics Laboratory low- turbulence ... The fan is an eight blade wooden fan driven by a 3 -phase 40 kW electric motor, capable of driving the tunnel to just above 200 feet per second. ... pressure differential electronic force transducer, which fed into a voltmeter and into the data analysis program in a PC computer.
|Title||:||The Vortex Flap|
|Author||:||Brandon T. Buerge|
|Publisher||:||ProQuest - 2008|