Simultaneous and Time Series Measurements of Two-Dimensional Velocity and Temperature Fields Using an Image Processing Technique

The spatial and simultaneous qualification of velocity and temperature field of flow has been made using image processing for understanding large scale structures of thermal mixing and a time dependent movement of vorticies. The velocity vectors were obtained by the cross-correlation technique which estimates a displacements of particle groups in two pictures of the flow field taken a short interval time, and the velocity vecters are calculated from the displacements dividing the interval time. The temperature measurement was performed by the laser induced fluorescence technique. The radiation of a excited fluorescence is varied with the dye temperature effectively. The temperature is estimated from a relation between the radiation intensity and temperature. The intensity in the thermal field can be measured by a CCD camera without a special optics or image intensifier. The system, with these two techniques, are applied to the natural convection, and presented the spatial and time dependent motion of the voltices. The efficiency of this technique was well confirmed. (Author)
This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992, AD-A258 510