Abstact
The development of a measurement system for the visualization, topological classification and quantitative analysis of complex flows in large-scale wind tunnel experiments is described. A new approach is sought whereby the topological features of the flow, e.g. stream lines, separation and reattachment regions, stagnation points and vortex lines are extracted directly and are preferably visualized in real-time in a virtual wind tunnel environment. The system is based on a stereo arrangement of two CCD cameras. A frame rate of 120 f/s allows measurements at high flow velocities. Helium filled soap bubbles are used as tracer particles. The present paper describes a simple camera calibration procedure for large measurement environments and examines the problem of fast and accurate reconstruction of path lines in three dimensions, which will enable true three-dimensional and time-resolved fluid flow visualization. Experimentally obtained visualization results for a free-stream flow, flow around a circular plate and flow over a delta wing are presented.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Borghese, N. A. and Cerveri P., Calibrating a Video Camera Pair with a Rigid Bar, Pattern Recognition, 33 (2000).
Doh, D. H., Kim, D. H., Cho, K. R., Cho, Y. B., Lee, W. J., Saga, T. and Kobayashi, T., Development of Genetic Algorithm Based 3D-PTV Technique, Journal of Visualization, 5-3 (2002), 243–254.
Dierckx, P., Monographs on Numerical Analysis: Curve and Surface Fitting with Splines, Oxford Science Publications, (1993).
Hartley, R. I., In Defense of the Eight-Point Algorithm, IEEE Transactions on Pattern Analysis and Machine Intelligence, 19-6 (1997).
Longuet-Higgins, H. C., A Computer Algorithm for Reconstructing a Scene from Two Projections, Nature, 293 (1981), 133–135.
Machacek, M. and Rösgen, T., Development of a Quantitative Real-Time Visualization Tool Based on 3D-PTV, Proc. 9th Int. Symp. on Flow Visualization, Edinburgh, (2000), 199.1–199.9
Machacek, M. and Rösgen, T., Development of a Quantitative Flow Visualization Tool for Applications in Industrial Wind Tunnels, Proceedings of the 19th Int. Congress on Instrumentation in Aerospace Simulation Facilities, Cleveland, Ohio, (2001).
Hartley, R. and Zisserman, A., Multiple View Geometry in Computer Vision, Cambridge University Press, (2000).
Takehara, K. and Etoh, T., A Study on Particle Identification in PTV-Particle Mask Correlation Method-, Journal of Visualization, 1–3 (1999), 313–323.
Author information
Authors and Affiliations
Additional information
Thomas Rösgen: He is a Professor of Fluid Dynamics at the Institute of Fluid Dynamics/ETH Zurich. Following his Ph.D. studies in aeronautics at the California Institute of Technology (Pasadena, USA) he held several positions at Stuttgart University (Germany) and the Technology Research Center of the European Space Agency (ESA-ESTEC, Noordwijk, Netherlands). His research activities are primarily in the area of modern electro-optical and imaging diagnostics for fluid dynamical applications.
Matthias Machacek: He studied mechanical engineering at ETH Zurich and presented his master’s thesis in 1998 based on research conducted at the Turbulence and Heat Transfer Laboratory of the University of Tokyo, where he was a visiting researcher in 2000. He is curently where he received his Ph.D. degree in 2003 at the Institute of Fluid Dynamics/ETH Zurich.
Rights and permissions
About this article
Cite this article
Machacek, M., Rösgen, T. Fluid flow visualization by three-dimensionally reconstructed tracer path lines. J Vis 6, 115–124 (2003). https://doi.org/10.1007/BF03181616
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF03181616