The flow field visualization technology visually displays the abstract calculation results of CFD numerical simulation in the form of graphic images, enabling users to easily analyze, compare, and study the results.However, the complex flow of CFD numerical simulation, huge generated data and complex data type make it difficult to conduct feature extraction, and thus difficult to achieve efficient visualization. The National Numerical Windtunnel (NNW) Project develops a field visualization software system, NNW-TopViz (TopViz for short), which has the function of field data processing, feature extraction, geometric drawing and human interaction. According to the efficiency requirements, TopViz deploys thread level parallelism to enhance the visualization computing. Due to the difficulties in flow field feature extraction and the low efficiency of conventional methods, TopViz implements the convolutional neural network-based flow field vortex feature extraction method, which improves the accuracy and efficiency of feature extraction. In order to improve software interaction efficiency and provide convenient interaction mode and experience, an immersive virtual display and interaction platform is built based on head-mounted display device and motion-sensing controller. TopViz realizes two interaction methods, namely gesture and eye gaze, and provides a multi-view and multi-angle flow field detection method in an immersive environment.
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