Application Technique of the FEM to Turbine Blade Vibration

Abstract

Along with recently distinguished clamour for improved performance and reliability of the gas and steam turbine now in wide use both for marine and land purpose, the renovated design techniques have become indispensable for the rotating blade of the turbine in the sphere of fluid hydraulics and vibration stiffness.
In reality, the rotating blade is used where the centrifugal force works, besides being complicated in its style in a form of curvilinear unit, furthermore, at the time of its designing, extremely accurate calculation of estimated vibration is required for preventing inevitable resonance due to harmonic vibration. A practical analysis method must be therefore be established, taking these specific characteristics of the blade into consideration. Accordingly, pinpoint accurate calculation will naturally necessitate large sized FEM models, with simplified disposal of Input/Output data and reduced cost of calculation becoming pivotal requirements for practical use. In order to satisfy these prerequisites, this report was prepared to illustrate in summary as to how we have developed the practical FEM design/calculation method and then put into physical utilization at an improved accuracy, as we have confirmed from our shop tests for comparison.