Vibration Analysis of Rotating Compressor Blades

Abstract

Calculation of the total potential energy of a system is performed in the case of thin rotating plates. The structure is divided into plane triangular elements with three nodes and eighteen degrees of freedom. The mass and stiffness matrices in which the rotation effects have been introduced are derived using area coordinates. First, the initial stresses due to the rotation are calculated; next, frequencies and modes are determined by a simultaneous iterative technique. The method is then applied to an existing compressor blade. The correlation with experimental results is good for the first ten frequencies and the first five modes. A calculation process for machine designers based on the methods introduced by Petricone-Sisto and Rawtani-Dokainish and the finite element method is then presented.