General Capability of Parametric 3D Blade Design Tool for Turbomachinery

Abstract

A design tool for generating 3D blades for various turbomachinery applications using a parametric approach has been developed. The tool can create a variety of 3D blade geometries based on only a few basic parameters and limited interaction with a CAD system. A general approach for creating the blade geometries is implemented which makes it robust and easy to create different 3D blade shapes for various turbomachinery components. The geometric and aerodynamic parameters are used to create 2D airfoils and these airfoils are stacked on the desired stacking axis. The tool generates a specified number of 2D blade sections in a 3D Cartesian coordinate system. These sections can be lofted in a CAD package to obtain a solid 3D blade model, which has been demonstrated using Unigraphics-NX and Solidworks. The geometry modeler can also be used for generating 3D blades with special features like bent tip, split tip and other concepts, which can be explored with minimum changes to the blade geometry. The use of control points for the definition of splines makes it easy to modify the blade shapes quickly and smoothly to obtain the desired blade model. Blade shapes for axial turbomachines, radial turbomachines and wind turbines are generated to show the general capability of the tool. Other novel blade shapes are also shown which shows the full utility of this tool when integrated with CAD. The executable of the code that generates sections is freely available on the web.