Volume 3, Issue 6, November 2017, Pages: 61-65
Received: Nov. 1, 2017;
Accepted: Dec. 12, 2017;
Published: Jan. 8, 2018
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Yifu Bai, Department of Civil, Environmental and Geomatic Engineering, University College London (UCL), London, United Kingdom
Gravity currents which are driven by body gravity forces, occur in the natural environment frequently, such as sea breezes, turbidity currents and avalanches, and sometimes cause natural and environmental disasters around the world. The cause of gravity currents is that the fluid of one density propagates into another fluid of a different density and the motion is largely in the horizontal direction. The objective of this study is to investigate the motion of density driven flows along a horizontal surface and within a stratified fluid, and measure their speeds by the simulation experiments of gravity currents. The speed of the gravity current is constant and able to be calculated with the speed formula. Meanwhile, compare the results with theory for gravity currents and intrusions, estimate theoretical constant parameter and research the behaviour of real fluids. In the experiment, the denser fluid dropped down to the bottom of the tank after the barrier was moved. Next, the fluid moved to the right side of the tank and kept the same shape travelling to the end of the tank. After reaching the end of the tank, the front of the fluid is mixed into the whole fluid. As an inference of this study, it is concluded that the low flow speeds the currents were not influenced by the friction by means of experimental data processing. According to the records of the motion of flows and the behaviour of fluids, the velocity was not constant with distance along the tank due to the human errors of records.
A Study of the Simulation Experiments of Gravity Currents, Fluid Mechanics.
Vol. 3, No. 6,
2017, pp. 61-65.
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