In mechanical systems there are numerous applications of torque, which result in the failure of a component due to shear stress if not properly designed. It becomes essential to examine the amount of torque, so that the component can be sustained without failure. The Finite Element Method (FEM), which is now increasingly becoming an integral tool for CAD due to the ongoing revolution in computer field, is used for the analysis of torque by a number of researchers. The FEM orientation has an effect on the accuracy of the solution. The present work describes the effect of triangular FEM orientation with regard to torsion.

The paper analyzes the effect of mesh orientation on the beam member when subjected to torsion, using the Finite Element Method (FEM). Nouailhas and Cailletaud (1995) investigated the macroscopic behavior of single-crystal super alloys under tension-torsion or torsion loadings. Specific tests were performed using the finite element analysis at room temperature on a tubular specimen equipped with micro-strain gauges for local deformation measurements, and a comparison of theoretical and experimental results was made. Loughlan and Ata (1995) gave a simple engineering theoretical analysis which was able to predict the initial constrained torsion response of a specific class of thin walled open section carbon fiber composite beams. This procedure accounts for the effect of primary warping constraint only and thus its application is restricted to the behavior of sections for which primary warping is predominant. The effects of secondary warping through the thickness of the thin walls are precluded in the theoretical approach.

A finite element study was done and was compared with the simple engineering theoretical approach for the Z and channel sections. Morrell et al. (1996) studied the effect of torsion, which, when applied to one member of a structure formed from two thin-walled open members connected at 90°, can result in torsion as well as flexure in the second member, with the magnitude and direction of this torsion and flexure being determined by the type of the joint used. The results of the finite element study of structures formed from thin-walled channel sections connected by box, mitre and stiffened mitre joints were presented and an explanation for the behavior of the different joint types was given. It was shown that for the box joint, the warping deformation of the loaded member was the dominant factor in determining the magnitude and direction of the twisting of the second member, whilst this was primarily determined for the stiffened mitre joint by the St Venant rotation deformation of the loaded member. For the unstiffened joint, it was shown that the warping and St Venant rotation deformation effects tend to cancel out each other. Takenori et al. (1998) used the impulse frequency response vibration technique for determining the shear modulus of glass/epoxy, graphite/epoxy and hybrid (glass-graphite/epoxy) pultruded cylindrical composite rods in torsion.

Mechanical Engineering Journal, Finite Element, Mesh Orientation, Mechanical Systems, Finite Element Method , (FEM), Numerical Analysis Technique, Geometry, Potential Energy, Torsional Problem, Finite Element Analysis, Gauss Elimination Method,Asymmetric Shear-Wall Structures.