Methodology of impeller curved vanes modelling in 2D axisymmetric stress analysis

Abstract

The purpose of this paper is to propose a more suitable methodology of impeller vanes modelling in axisymmetric 2D models which improves the results but does not increase the computational complexity of the task. For this purpose, two different approaches have been tested which led to a significant improvement in 2D axisymmetric model results. The first approach directly models the spatial curvature of the vanes using shell elements which are connected to axisymmetric disk elements using coupled degrees of freedom. The second approach modifies the commonly used methodology which simulates the vanes using plane elements under the plane stress conditions. The influence of spatial curvature of the vanes is then empirically considered by reducing the Young’s modulus of elasticity of vanes material. In addition, this approach has been extended using orthotropic material that allows material properties to be changed in certain directions. Advantages and disadvantages of these approaches are reported.

Keywords

• finite element method
• 2d axisymmetric model
• impeller
• curved vanes
• rotor
• compressor
• turboprop