Determination of Inflow Distributions from Experimental Aerodynamic Loading and Blade-motion Data on a Model Helicopter Rotor in Hovering and Forward Flight PDF Download

Author: Gaetano Falabella
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 184

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Book Description
Inflow distributions, azimuth and spanwise, were determined analytically from measured pressure distributions and blade-motion data on a model helicopter rotor blade under hovering and simulated forward-flight conditions. Pressures and corresponding blade flapping were recorded for various rotor conditions at tip-speed ratios of 0.10 to 1.00. Included in this range are one-bladed-rotor operation effects, deliberate blade stall, data on the effects of cyclic pitch, and tests on a rotor with 13-percent-offset flapping hinge. Since the offset-flapping-hinge rotor was used primarily as a means of alleviating stall in order to obtain inflow data at high-tip-speed rations (mu) in the vicinity of 1.0, no cyclic pitch was used to balance out the hub moments resulting from the incorporation of offset hinges. It is these moments which are the primary source of the stall alleviation.