Motion of 2D Buoyant Clouds Downslope
Publication: Journal of Hydraulic Engineering
Volume 125, Issue 5
Abstract
The motion of conservative 2D thermals on beds with slope angles θ ranging from 5 to 90° is investigated theoretically and experimentally. Using a large number of experimental data, important flow characteristics, including the shape factors, spatial growth rate, propagation speed, and entrainment coefficient, are quantified as functions of bottom slope angles. A thermal model, which includes a resistance term, is developed. It is found semiempirically that resistance coefficients Cd are almost independent of θ and the values of Cd are in the range of 0.4–0.6. Capability of the model is demonstrated by comparing numerical results with theoretical as well as experimental results.
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Information & Authors
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Published In
Journal of Hydraulic Engineering
Volume 125 • Issue 5 • May 1999
Pages: 474 - 480
History
Received: Jun 13, 1996
Published online: May 1, 1999
Published in print: May 1999
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