Study on three dimensional parametric feature modeling method and generation of hexahedron mesh for impeller and blade of turbomachinery

Impeller is a key component of centripetal turbine and centrifugal compressor and has very complex geometry. It is very important to obtain accurate numerical results by FEA (finite element analysis) using perfect mesh. Based on the structural feature of impeller, CAGD (computer aided geometric design) was adopted to develop its three dimensional parametric feature modeling method. Then homeomorphism principle and other methods as BMSweeping(sweeping via background mesh interpolation) and so on were used to develop generation method of hexahedron mesh for impeller. In order to improve accuracy of numerical results by FEA, some special mesh generation methods for fillet on the bottom of blade and inlet of flow channel have also been developed to obtain good mesh. The mesh for a centripetal impeller of a 100 kW microturbine was generated, it shows the mesh is perfect and can satisfy the requirement of FEA.