Title : Vibration suppression of laminated composite wind turbine blades reinforced with nanoparticles
Abstract:
Non-uniform thickness laminated composites are being used in wind turbine blades. Recently, to enhance the strength and dynamic performance, nanoparticles are being added to the conventional matrix as a reinforcement. The present work investigates the effect of volume fraction of nanoparticles on the dynamic response of the blades. A laminated taper beam in which the matrix is reinforced with nanoparticles is considered to study the effect of volume fraction of nano particles on the natural frequency and damping properties of the blade. By adding nano particles up to 3% increases the natural frequency and beyond 3% and up to 7% natural frequency decreases. At 10% the natural frequency sharply declined. However, the damping coefficients of samples significantly improved. Further, piezoelectric elements, as actuator and sensors, are mounted on the outer surface of blade, smart blade, to control the vibration in random loading conditions. An optimal control algorithm, Linear Quadratic Regulator (LQR) is implemented to suppress the vibration of the blade and to study the effect of nanoparticles in actuating force. It is observed that adding 10% of nano particles to the matrix significantly reduces the actuating voltage required to suppress the vibration. The proposed smart laminated blade improves the performance and functionality of wind turbine blades under in-deterministic loading conditions.
