ATMOSPHERIC DIFFUSION OF PUFFS. SIMULATION IN A WIND TUNNEL
Laser tomography and digital image processing were applied to flow visualization and determination of instantaneous particles concentrations, in turbulent flows, in wind tunnel simulations of short accidental releases. There, determination of instantaneous concentration fields is essential: time and length scales ratios are equal, but peak to average concentration ratios may be elevated. The method was rendered operational. It requires processing many images and much computer time for each case treated. Images of puffs, from a point source, were recorded at two times after release. Five cases, with different thermal - geometrical conditions were treated. Mean fields, root mean squares of concentration fluctuations were determined. Probabilities of occurrence of concentrations higher than given levels were derived and plume spatial characteristics were utilized to describe puff diffusion. Data obtained may already validate numerical models. However, for stabler statistics, more images would be needed and stronger thermal stratifications should be investigated to quantify buoyancy influence on puff dispersion.
Bibliographic Reference: EUR 9286 EN (1984) FS, 84 P., BFR 300, EUROFFICE, LUXEMBOURG, POB 1003
Availability: Can be ordered online
Record Number: 1989123035600 / Last updated on: 1987-01-01
Available languages: en