Abstract: The aeroelastic stability behavior of a helicopter rotor blade in hover with transverse shear deformation and warping is investigated by using the finite element method in this paper. A 21-DOF beam finite element, including transverse shear DOF and warping DOF, is developed for analysis. The governing differential equations of motion for hingeless rotor can be derived using the Hamilton’s principle. Numerical simulations are carried out to validate the current analysis of other literature. The influences of transverse shear deformation and warping on the natural frequencies and aeroelastic behavior of soft-in-plane hingeless rotor blade are investigated. With the inclusion of transverse shear and warping, there is a decrease in the rotation natural frequencies. It is also seen that the transverse shear deformation and warping have effects on the aeroelastic stability of the rotor blade. These effects become larger at the higher thrust level.

Key words: helicopter, blade, aeroelasticity, transverse shear, warping