Axisymmetric Bending of Physically Nonlinear Rotating Discs.

The aim of this paper is to present a more adequate approach to the problem of symmetrical bending of rotating discs based on a system of equations for a disc made of a physically nonlinear material. Assuming that the material is homogeneous, isotropic and incompressible, that the theory of small deflections is valid and that mass forces are dominant - a solution for the instantaneous state is obtained. By applying the elastic analog (usually attributed to N. Hoff), a solution of the problem of steady creep can be obtained. The solution procedure is based on a combination of Runge-Kutta and Bubnow-Galerkin methods, the distribution of stresses and displacements being determined as a function of a dimensionless radial variable number of interesting conclusions can be drawn from the numerical results. It is shown that the bending of a rotating disc may cause creep rupture. The neglect of the bending state in the computation of a jet engine may lead to incorrect results.