Modal analysis of the low pressure frame of a steam turbine

Krawczuk, M., Murawski, L., Ostachowicz, W.M. and Cartmell, M.P. (1995) Modal analysis of the low pressure frame of a steam turbine. In: ASME International Joint Power Conference, Minneapolis, USA, 8-12 Oct 1995, pp. 275-287.

Abstract

The objective of this paper is to present the application of the ADINA Finite Element code to the modal analysis of the whole of the low pressure part of a turbine frame. The model comprises a frame represented by isoparametric shell finite elements (each one having 8-nodes and 5 d.o.f per node) whereas the stiffeners are modelled by bar finite elements (each with 2 nodes and 3 d.o.f. per node). In this way the ultimate geometrical description of the system contains 12,000 nodes and above 40,000 d.o.f. It should be pointed out that the weight of the water inside the condenser is included in the analysis and the accurate deformations of the frame have been obtained by application of the modified Newton procedure. As a second step the natural frequencies and the mode shape have been calculated by means of the method of subspace iteration with acceleration. The results of the numerical calculations show that the forces acting on the frame influence the natural frequencies and the mode shapes.

• Item Type: Conference Proceedings
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cartmell, Prof Matthew
• Authors: Krawczuk, M., Murawski, L., Ostachowicz, W.M., and Cartmell, M.P.
• Subjects: T Technology > TJ Mechanical engineering and machinery
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy