Unsteady Aerodynamic Loads Determination in Rotors with Multiple Oscillating Trailing Edge Flaps

Students : Devesh Kumar

Sponsor : Vertical Lift Rotorcraft Center of Excellence (VLRCOE)/U.S. Army


Develop framework of aeroelastic model of rotating wings with camber-wise deformable airfoils for enhance performance and vibration characteristics associated with rotorcraft.

Vibration reduction is desired in helicopters to ensure passenger comfort and to meet the increasingly stringent vibration and noise levels. Among various active control strategies, actively controlled flaps (ACF) have shown tremendous potential in vibration reduction. In addition, they show possibility of simultaneous noise reduction and performance enhancement. However, until now, unsteady drag produced by oscillating trailing edge flaps has not been obtained experimentally, but is required to determine performance penalty due to ACF. More recently, microflaps have been used on fixed wings for flutter suppression and aeroelastic vibration control. Thus there is need to experimentally verify the potential of microflaps in vibration reduction and performance enhancement on rotor blades.

Principal objectives of this project are:

  • Design and model composite rotor blade with trailing edge flaps and microflaps.
  • Fabricate blade with ACF and microflaps using appropriate actuators of high bandwidth
  • Experimentally obtain unsteady aerodynamic loads on rotor blade with oscillating trailing edge flaps on Mach scaled hover test stand.
5ft Mach scaled CH-47D rotor blade with dual active flaps
Spin test stand for determining unsteady aerodynamic loads

Top Camera from A2SRL on Vimeo.

Hub Camera from A2SRL on Vimeo.