“DANUTA,” A Three-Dimensional Finite Element Program Used in the Analysis of Turbomachinery

Abstract

A three-dimensional structural analysis program (DANUTA), using newly developed subparametric finite elements, is described and applied to the analysis of turbo-machinery components. The hexahedron-shaped element has twelve generalized displacements concentrated at each of the eight corner nodes. The displacement components are represented by a complete third degree polynomial, with some selected terms of the fourth and fifth degree, while the geometry is described by a set of second order parametric interpolation functions. The derivation of the stiffness and consistent load matrices (surface and body forces) is outlined. Numerical results, for cases where a classical solution is available, illustrate the high accuracy of the element. Application of the program to the analysis of spherical valves, turbine runners and wicket gates, as well as machine requirements, automatic data generation and possible further developments are discussed.