Reynolds Number Effects on the Nearfield Mean Characteristics of a Laboratory Model Thermal Plume

Laboratory model data are presented for the three dimensional time averaged thermal characteristics of a buoyant rectangular surface thermal plume in a crossflow. Plume trajectories and widths, as determined from dye studies and thermocouple measurements, and isotherm contours have been obtained for internal Froude numbers ranging from 0.79–1.3, for crossflow-to-jet velocity ratios of 0.56 and 1.13, at a nominal Reynolds number of 20,000 and a Froude number of 0.058. These data are compared with earlier model studies at lower Reynolds number, where a surprisingly large effect of Reynolds number upon buoyant jet development has been found.