Abstract
Although the integration of computation and experiment in fluid dynamics has been steadily progressing, and the recent development of measurement techniques of flow velocity enables us to obtain highly accurate data for various flow fields, several difficulties occur in a real environment. One of most difficult issues is how experimental data can be easily obtained in a wide region. In this study, we propose a portable flow visualization device system, which focuses on the cost-effectiveness and easy handling. In this paper, two measurement techniques of three-dimensional flow velocity are introduced. One is a measurement method of three-dimensional flow direction using tufts, which the locations of the endpoints of the tuft are automatically measured by two or more versatile USB-cam and recent image processing libraries. The other is a new method of generating a slit light using rotating multiple light sources. It is shown that, in a real environment, the three-dimensional coordinates of two endpoints of the tufts are obtained by the proposed method, and the flow field around a bluff body is visualized using a slit light which generated by the rotating multiple light sources.
