The use of aeroelastically scaled helicopter rotor wind-tunnel models in establishing or verifying the dynamic characteristics of new or existing rotor designs is discussed. A model, termed the generalized rotor aeroelastic model (GRAM), which has been developed for testing aeroelastically scaled rotor models is described, and the utility of the model in being able to test a variety of rotor systems to meet a broad range of test objectives is demonstrated though presentation of data from recent tests. Data are presented from tests of an AH-1G Cobra model to determine whether or not the two-blade teetering rotor can experience stall flutter, tests of two wide chord teetering rotors to evaluate the effect of the wide chord on blade loads and rotor performance, and tests of a new four-blade flex-hinge rotor configuration to provide information for the designer relative to its dynamic characteristics. Since the GRAM was developed for testing in a wind tunnel which has the capability of using Freon-12 as a test medium, some of the advantages of Freon-12 for testing of aeroelastically scaled models are also discussed. (Author)
Wind-Tunnel Testing of Aeroelastically Scaled Helicopter Rotor Models
1976
16 pages
Report
Keine Angabe
Englisch
Aircraft , Helicopter rotors , Aeroelasticity , Flutter , Wind tunnel tests , Rotor blades(Rotary wings) , Aerodynamics , Instability , Stalling , Aerodynamic loading , Experimental data , Airplane models , Helicopters , Wind tunnel models , Experimental design , Fluorinated hydrocarbons , Transonic wind tunnels , H-1 aircraft , AH-1G aircraft , Freon 12 , Generalized rotor aeroelastic models , GRAM(Generalized rotor aeroelastic models)