Smart spring control of vibration and noise in helicopter blades

Helicopters are versatile tools for many applications but unfortunately create significant vibration and noise. Traditional passive and active approaches to suppress these vibrations are either effective only at specific frequencies or limited by electromechanical capabilities of smart actuators to overcome the severe aerodynamic conditions. The Smart Spring is a device that avoids these limitations by only altering the structural impedance properties of the blade root. It is desired to implement a numerical tool to analyze the effectiveness of the Smart Spring and to perform efficient parametric studies. In the paper, the Smart Spring is modeled in the SMARTROTOR aeroelastic/aeroacoustic helicopter code as part of the pitch link. It is verified that the Smart Spring is an effective tool for suppressing vibratory loads passing through the pitch link to the airframe. Copyrigh