Techniques for Modeling Torque Transfer between Concentric Cylindrical Components

Finite elements that use a piecewise linear approximation of geometry are perfectly adequate for modeling cylindrical components such as shafts and hubs in many applications. However, linear elements present a challenge to the assessment of contact interfaces between curved surfaces, namely that faceted surfaces have peaks and valleys that can interlock with each other. A good example is when torque is transferred between a shaft and a hub via a key, collar, pin, or some other means. In this case, it can be difficult or impossible to control how the applied torque is shared between the interlocking mesh and the intended torque transfer device. If the goal of the analysis is to determine the strength of the actual torque transfer features (e.g., a keyway or spline), then it is critical to apply the correct load to them by eliminating or at least minimizing mesh interlocking. This paper discusses various strategies for circumventing the mesh interlocking problem.