A Wind-Tunnel Investigation of the Aerodynamic Environment of a Full Scale Helicopter Rotor in Forward Flight
BELL HELICOPTER TEXTRON INC FORT WORTH TX
Pagination or Media Count:
Aerodynamic data were measured at one blade radius station as the initial phase of a program designed to define the aerodynamic environment over the entire rotor disc. The rotor was instrumented to measure stagnation point location, radial flow direction, and pressure distributions. These data were then used to determine angle of attack effective airfoil profile section normal force, chord force, and pitching moment and stall and unsteady aerodynamics effects. The test data were compared with two-dimensional empirical data and theory. Four cases were analyzed in some detail. They showed the variations in airfoil pressure, angle of attack, and radial flow as functions of aximuth and advance ratio. Deviations in the pressure distributions between test data and theory are believed to be due to the rotor wake and unsteady aerodynamic effects.