An experimental study of round buoyant turbulent plumes is described, emphasizing conditions where the flow has lost source momentum and other source distrubances, and has become self preserving. Plume conditions were simulated using dense gas sources in a still and unstratified air environment. Mean and fluctuating mixture fractions and velocities were measured using laser-induced fluorescence and laser velocimetry, respectively. The present measurements extended farther from the source than most earlier work (up to 151 source diameters and 43 Morton length scales) and show that self-preserving plumes are narrower and have large mean properties near the axis than previously thought. Although contemporary turbulence models yield reasonably good predictions of mean properties in the self-preserving region, there are difficulties with many of the approximations concerning turbulence properties; this raises questions about the potential effectiveness of these models for predicting the properties of the complex buoyant turbulent flows that are encountered in practical fire environments.
U.S./Japan Government Cooperative Program on Natural Resources (UJNR). Fire Research and Safety. 13th Joint Panel Meeting. Volume 1
fire safety, fire research, buoyant plumes, velocity, experiments
and Kasper, K.
Characteristics of Oscillating Buoyant Plumes., U.S./Japan Government Cooperative Program on Natural Resources (UJNR). Fire Research and Safety. 13th Joint Panel Meeting. Volume 1, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916891
(Accessed February 21, 2024)