Study On Parametric Modeling Method And Generation Of Hexahedral Mesh For Blisk

This thesis introduces structural feature of blisk. Blisk is a key component of Aeroengine because it works with high-speed rotation. Compared with the traditional structure with mortise-and-tenon joints, blisk has following characteristics: light weight, simple structure, less components and high reliability. Blisk has very complex geometry and its working conditions are bad because it must bear the enormous centrifugal force and the effect of high-temperature gases at runtime. In order to ensure the safety of blisk, person must obtain its precise characteristic of vibration using FEA (finite element analysis) in design stage. High-quality 3-D finite element mesh is to guarantee the accuracy of analysis. Hexahedral mesh has advantage in FEA, such as: the description of geometry entity is precise, computation precision is high and numerical result is stable.Open CASCADE is a CAD/CAM platform.The thesis studies the method of parameterized solid modeling based on Open CASCADE platform. The method is put into practice in parameterized design of blisk.Based on the structural feature of blisk, sweeping was adopted to generate its hexahedral mesh. First, paving was used to generate quadrilateral mesh on source surface of blisk. Then the projection of a source surface mesh onto the target surface was carried out by means of a least-square approximation of an affine mapping defined between the parametric spaces of the surfaces. At last, BMSweep was used to locate interior nodes during sweeping after all side areas were meshed.The mesh for a blisk was generated, it shows the mesh is perfect and can satisfy the requirement of FEA.