Modified Thermal Theory for Gravity Currents on Sloping Boundaries
Publication: Journal of Hydraulic Engineering
Volume 136, Issue 10
Abstract
In this study, we generalize the classic thermal theory to account for both entrainment and detrainment effects occurring in the acceleration and deceleration phases of gravity current motion. Although the original thermal theory qualitatively captures the two phases of gravity current motion, the pure entrainment model appears to underpredict the gravity current velocity and the distance before the maximum velocity is reached. We theoretically show that detrainment increases the predicted maximum velocity of gravity current and extends the predicted distance before the maximum velocity is reached. Furthermore, based on the experimental data reported in the literature, the detrainment coefficient appears to increase as the bottom slope increases.
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Acknowledgments
The research was supported by the National Science Council of Taiwan through Project No. NSCTNSC 98-2218-E-032-007.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 136 • Issue 10 • October 2010
Pages: 826 - 830
Copyright
© 2010 ASCE.
History
Received: May 20, 2009
Accepted: Mar 29, 2010
Published online: Sep 15, 2010
Published in print: Oct 2010
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