Wind Tunnel Experiments on Cooling Tower Plumes: Part 1—In Uniform Crossflow

Abstract

Measurements of velocity and temperature field and flow visualization results are reported for an ideal case of a cooling-tower plume in the presence of a uniform crossflow for various velocity ratios, densimetric Froude numbers, and Reynolds numbers. Coherent structures in the form of jetlike, wakelike, or mushroom-type vortices have been observed. The type of structure depends primarily on the velocity ratio. As the Reynolds number increases, turbulent structures appear, which have vorticity of the same sign as the partner vortices in the low Reynolds number case. The measurements showed that there is a strong interaction between the bending plume or jet and the wake of the cooling tower, which is basically responsible for the downwash effect. The latter is generally quite strong at low velocity ratios and high Reynolds numbers. High turbulence intensities are produced in the wake of the tower for a distance of 6 to 8 diameters. The plume is diluted faster as the velocity ratio increases and buoyancy decreases. In the wake region of the stack dilution increases with increased buoyancy.