Finite Element Analysis of Fir-Tree Blade-Disc Assembly

Abstract:

The safe operation of industrial gas turbines is dependent on the structural integrity of the critical geometrical features such as blade-disc attachments. Knowledge of stress distribution in this region is the principal necessity for damage tolerance analysis and lifetime estimations. The finite element analysis which includes contact between two deformable bodies is complicated and takes extensive computational costs. A simplified FE model is needed which could predict the stress distribution without modeling the exact contact features. The main objective of this study is to present and compare two simplified FE models which can predict stress distribution at blade disc interface. Fir-tree region in a gas turbine disc assembly is modeled and comprehensive 2D and 3D non-linear finite element analysis is carried out. FE results are verified using photo elasticity method.

• Periodical: Applied Mechanics and Materials (Volume 392)
• Pages: 191-196
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.392.191
• Online since: September 2013
• Authors: Ashkan Dargahi, Mehdi Masoudi, Soheil Nakhodchi
• Keywords: Finite Element, Fir-Tree Blade-Disc Assembly, Gas Turbine, Stress Analysis

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