Analysis for Flutter velocity in large wind turbine blade

The present paper investigates the evaluation of flutter analysis of horizontal axis (100m) wind turbine blade (HW AT), with DU-97-W-300 aerofoil cross section using mathematical model supported by standard Finite Element Analysis. The FEA codes along with PK - method is carried out for finding flutter solutions whereas Double Lattice Method is used for finding matrices and aerodynamic loads. Galerkian equations are utilized to solve the problems associated with the equations of motion. The study analyses the coupled mode flutter of rigidly fixed, flexible aerofoil. The results presented in this paper shows the significant impact of first torsion and third flapwise bending modes in the motion of blade structure. Further the study focuses on the improper isolation of torsional natural frequencies which resulted in poor flutter performance of the blades associated with the lowering of critical velocity into the operational ranges.