Shear buckling of a composite drive shaft under torsion

In this research the torsional stability of a composite drive shaft torsion is studied. Composite materials are considered as the suitable choice for manufacturing long drive shafts. The applications of this kind of drive shafts are developed in various products such as cars, helicopters, cooling towers, etc. From the design point of view, local and global torsional instability of drive shafts limits the capability for them to transfer torque. After reviewing the closed form solution methods to calculate the buckling torque of composite drive shafts, a finite element analysis is performed to study their behavior. Furthermore, to evaluate the results obtained by the finite element method, a comparison with experimental and analytical results is presented. A case study of the effects of boundary conditions, fiber orientation and stacking sequence on the mechanical behavior of composite drive shafts is also performed. Finally, the reduction of the torsional natural frequency of a composite drive shaft due to an increase of applied torque is studied.