Blisk Feature-based Cad Modeling Systems

Blisk is one of the most important parts in the aero-engine. It is wildly using in engine fan, turbine and so on. The blisk is a new structure which can increase capability, predigest structure, lower weight, reduce fault, and improve wear and dependability of the engine. Blisk has multiplicity sharp, complicated structure and many dimensions. And presently domestic blisk design is two-dimensional design based CAD software, which can not satisfy the needs of concurrent design. So the structural design is difficult to change and design process is very long. The three-dimensional parametric feature modeling method based CAD software, which can realize blisk fast modeling, provide sharable model for analysis and machining. Hence the cycle is shortened.In this paper, the key technologies of the aero-engine blisk are studied based on the deep analysis of the structure and design methods about blisk .A method is presented to make the structural design process be three-dimensional, and a system of blisk modeling is provided. Hence the cycle is shortened.Some key technologies used in the system are as follows:Firstly, the structure and modeling method of blisk are studied. In this paper, the structure of blisk has been concluded and classified, that is, opening blisk, closing blisk and big & small blade rotors. Also the structure and modeling process have been particularly analyzed.Secondly, the modeling method of blisk based on the feature has been studied. The blisk is divided into two main parts based on the blisk's feature. Also the feature decomposition and simplification have been made for the blisk. Meanwhile, using the feature modeling method, the parametric modeling for the blisk has been made. In the process of the blade modeling, the joining method is given to create the smooth section lines of blade. The Sew method, Through Curve method and Through Curve Mesh method are presented to solve the modeling of blade surface which is a free 3D surface. Thirdly, in this paper, the Blisk Modeling CAD system is developed. Using the UG as the CAD platform, the second development has been made. The process of the blisk design is integrated into the UI and the CAD system of blisk is set up. Also, the examples of three representative structures are given.In this paper, the fast parametric modeling for the blisk structure is realized. This will be very convenient for the users to design and modify and provide a useful implement for the users to design and machining.