Design And Implementation Of The 3D Flow Field Visualization Algorithms Based On VTK

With the development of computer technology,numerical simulation has been used in the areas of scientific research and industrial production.Besides,the high simulation precision which creates great amounts of data makes it important for researchers to use data visualization methods to obtain useful information and flow field movement laws quickly and accurately from the mass data.Data visualization has been widely used in fluid dynamics study,biomedical research,industrial production and other fields.The computational fluid dynamic plays an important role in the area of aerospace and navigation,as well as shipbuilding industry.The visualization of 3D flow field can provide a way to research the dynamic characteristics,thermodynamic properties and motion laws of flow field.Therefore,the visualization of 3D flow field has become an important research direction in the field of visualization.The essence of 3D flow field visualization is to display the geometric structure and attributes of the flow field in the form of graphics and images.Among the visual software and tools,VTK(Visualization Tool Kit)has been widely used in many scientific research institutions and visual software development companies because it has powerful functions,short development cycle and strong adaptability of development platform,besides it supports for many programming languages.So this paper designed and implemented 3D flow visualization algorithm based on VTK.Based on the study of the composition and development methods of VTK's class library,the data types supported by VTK and the construction process of the visualization pipeline,the following three parts are completed.(1)Implement the reader and writer of various file types.Convert the Tecplot file type to VTK supported file type,which added a new class to VTK input and output class library.(2)Design and implement visualization algorithms for 3D structured grid data,which includes data detection,contour line and isosurface extraction,data cutting and color mapping,and glyph display for vector data.(3)Through the study of the classical volume rendering algorithm,the model of 3D flow field volume rendering based on the image data type and the model of 3D flow field volume rendering based on the unstructured grid are established.On the basis of the two volume rendering models,the ray casting volume render algorithm and the texture mapping volume render algorithm are used,and t he drawing effect is analyzed in the end.Applying the volume render method which is widely used in the medical research field to the 3D flow field visualization area provides methods for information exploiting of flow field.To sum up,on the basis of VTK,this paper has designed and implemented a series of methods for the visualization of the 3D structured grid flow field data in order to exploit the potential attributes information and provide the researchers with convenience to observe the flow field feature and motion laws to make correct decisions.