The Research On Pipe Flow Visualization Algorithm Based On Geometric Primitives

Fluid flow is an important phenomenon in the nature and industry. The visualization of flow field which describes the characteristic of fluid flow can help engineers to optimize the design of machine components. At present, two dimensional flow visualization techniques are mature, but visualization in three dimension space is far away from resolved. This paper focuses the research on the three dimensional interactive visualization of pipe flow field. The work plays an important role in studying the flow field structure which greatly influences the pipe system performance.On the basis of discussing the international current status of visualization technology, the geometric primitive technology which is fit for describing flow field in the virtual environment was selected in this dissertation. The streamline computing and rendering algorithms were the emphasis. First, a new method to select seed points was proposed. Seeding plane was designed according to the pipe geometry. A new idea, the order of numerical integration is determined based on Renault value, was thought up. A hierarchical point location method was put forward. A new geometric primitive structure streamline arrow which is convenient for animating streamline was presented. Based on this structure, multi-value map was realized. Secondly, flow field visualization technique was combined with soft-measure technology, and the virtual instrument and curve technology to show the data was integrated in the system. Finally, pipe fluid flow visualization system was designed and realized. The effectiveness of the algorithms proposed was validated through experiments.The algorithm put forward in this paper can reduce the computing time for constructing streamline. The geometric primitive streamline arrow can clearly describe the structure and characteristic of flow field, and show multiple flowfield attribute value in one picture.