Analysis and testing of Mach scaled rotor model with piezoelectric bender actuated trailing-edge flaps for helicopter vibration control

摘要

This paper presents on-going research directed towards the development of a Mach scaled rotor model with piezoelectric bender actuated trailing edge flaps for individual blade control of helicopter vibration. ^First, an analytic model is developed for the coupled actuator-flap-rotor dynamic response in hover. ^Then, the analysis is systematically validated by using test data obtained by hover testing a 6 ft diameter, Froude scaled rotor with piezobender actuated trailing-edge flaps. ^The analytic model shows good correlation with experimental flap deflections and oscillatory hub loads. ^For the Froude scaled model, flap deflections of +/- 4 to +/- 8 deg, for 1 to 5/rev flap excitation were achieved at 900 rpm. ^This flap activation resulted in a 10 percent variation in the steady rotor thrust level at 6 deg collective. ^Next, two Mach scaled rotor blades with piezobender actuation were designed and fabricated. ^The rotor was tested in the vacuum chamber and flap deflections of +/- 8 deg were achieved in vacuum at the Mach scaled operating speed of 2000 rpm. ^The analysis predicts that in hover, flap deflections of +/- 5 deg can be achieved at 2000 rpm. ^(Author)