Optimization of Turbine Disk Profiles by Metamorphic Development

Abstract

A novel topology/shape optimization method, Metamorphic Development, is applied to an axisymmetric thermo-elasticity design problem. Based on solid modeling and finite element analysis, optimal profiles of minimum mass turbine disks are sought by growing and degenerating simple initial structures subject to both response and geometric constraints. Radial stress, axial stress, hoop stress and von Mises stress are analyzed throughout the optimization and a constraint is imposed on von Mises stress everywhere in the disk. The optimal structures are developed metamorphically in specified infinite design domains using both quadrilateral and triangular axisymmetric finite elements. Comparisons are made of the results obtained for different optimization scenarios: (a) with and without thermal loading; (b) with and without centrifugal body forces; (c) with and without a fit pressure on the inner surface of the hub; and (d) operating at different rotational speeds.