Research And Application Of Key Technologies Of Digitized Design For Mechanical Product

Product design is the kernel to manufacturing industry. In recent years, modern design is replacingconventional design gradually with the help of IT technology, and many scholars have done research onmodern design methods. Digitized design technology covers the latest technologies of modern design,and also as the foundation of modern design, so study on it is very essential. Although a mass kind offarming equipment can be manufactured, the technical level and configuration of product in our countrycan hardly compete with those in developed countries. To the point, it's because the design, which isorigin, had no breakthrough development. Our research tries to introduce digitized design technology toagricultural machinery industry, to change conventional design method of agricultural industry, and topromote the design and manufacturing level of the whole farming equipment in our country.The author took submersible pump and combine as the example and researched the theory and relativetechniques of digitized design, the innovation points are as follows:Virtual prototyping, concurrent design under network, distributed computing model of collaborativedesign and simulation for multidiscipline are discussed, a VP-based developing framework of digitizeddesign is proposed, and is utilized for agricultural machinery development.3D modeling tactics for kernel flowing-passed components based on the result of hydraulic design arestudied, the feature-based modeling and parameter driving modeling is used to realize thesemi-automatic or automatic building for the components of submersible pump.The CFD analyzing model for forecasting the operation performance of submersible pump is built, themesh model, fluid-solid coupling model, turbulence model, discrete schemes, boundary condition forcalculation of submersible pump are discussed, and the virtual test of performance is realized.Furthermore, the velocity field and the pressure field on the surface of kernel components, such as bladeand guide vane which have essential effect on performance are analyzed.The process of virtual assembly is discussed. The product information is divided into four levels, namesas component-level, assembly-feature-level, geometry-face-level and face-piece-level according todifferent abstract extent. Reconstruction and assembly of components and parts for submersible pumpunder virtual environment are reached in virtue of mapping relationship between geometry elements andtriangle face piece.The virtual manufacturing of special surface on blade is described. The trajectories of the pressure andsuction surfaces of a blade are individually calculated according to the theory of differential geometry.The results indicated that for the pressure surface machining by a flat-end cutter, the trajectory could bedirectly calculated because there was no interference occurred, while for the suction surface, thecalculation should be made prior to the determination of whether the interference existed. A quickdetection method for global and local interference was developed and a suggestion of adopting theIso-Scallop method to obtain the optimum trajectory length was given.Case-based design technique is applied into the design process of agricultural machinery, with which...