ASYMMETRIC, SPEED DEPENDENT TENSIONING OF CIRCULAR ROTATING DISKS

Abstract This paper examines the effect of asymmetry on a novel, speed dependent, in-plane stress induction technique for rotating circular disks. Residual, in-plane stresses are frequently introduced into circular saws to extend the range of stable rotation speed. The new speed dependent technique considered here is theoretically twice as effective as traditional techniques. However, practical realization of this new technique can introduce asymmetry into the in-plane stress field, an effect that is normally not considered. In this paper, these asymmetries are explicitly examined in order to formulate design rules for the new stress induction technique. Finite element analysis indicates that at least five, evenly spaced, concentrated, in-plane loads are required along the inner radius of the disk to produce results identical to an equipollent, uniformly distributed load; four or fewer concentrated loads produce noticeably poorer results due to asymmetry. In performing these calculations, it was discovered that symmetry of the finite element mesh is essential for accurate prediction of small and vanishing natural frequencies. The viability of the new stress induction technique and the finite element predictions were both then confirmed experimentally.