Experimental Investigation of Velocity Profile in Interflow Density Current

Document Type : Research Paper

Authors

1 PhD Student, Hydraulic Structures Department, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

2 Professor, Hydraulic Structures Department, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

Abstract

Gravity currents, also known as density currents, or buoyancy currents, are happened by the density difference between the flow and its ambient fluid. Gravity current happen in geophysical environments. One of the most important types of these streams that occur in large-scale nature is density flow (Middleton 1993). These flows are happen due to gravity and its effect on the density gradient. When the gravity current arrived to ambient fluid, in the position that density of both gravity current and ambient fluid is equal the gravity current abandon the bed and flows in ambient fluid horizontally )He et al, 2016(. Some examples of gravity currents found in nature katabatic winds thunderstorms, dust storms (haboobs), turbidity currents running down the continental shelf, and advancing cold fronts )Thompson, 1986(. Examples of gravity currents found in industrial processes are the spread of heavy gases and also ventilation systems that utilize buoyancy to drive horizontal flows along the ceiling and floor )Samothrakis and cotel, 2006(. Other examples of gravity currents that are encountered in nature include snow avalanches )Hopfinger and Tochon-Danguy, 1977( and pyroclastic flows (Valentine, 1987). There are also examples of man-made gravity currents with industrial applications. Such an example is the instantaneous release of a dense gas in a less dense environment, after the failure of a containment tank (Baines, 2001). Simpson (1997) has detailed descriptions of these and other examples of gravity currents and also provides an overview of the research performed on the subject
In dams reserve ambient fluid, usually has a vertical stratification. Therefore, the density current into this reservoirs may flow as interflow. In this study, the density current was investigated in ambient stratification fluid. For Experimental Investigation of velocity profile in interflow density current at stratification ambient, experiments were performed by 4 discharge 1, 1.5, 2 and 2.5 liters per second, and 4 concentrations 5, 10, 15 and 20 grams per liters on the bed slope 2.5, 3.25 and 4 percent. Stratification of ambient fluid was carried out by mixture water and salt with a deep concentration gradient. To create density flow silica particles with an average diameter of 8 microns was used.

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References

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Irrigation Sciences and Engineering
Volume 47, Issue 2
September 2024
Pages 119-135

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History

  • Receive Date: 12 December 2017
  • Revise Date: 28 April 2018
  • Accept Date: 30 April 2018
  • Publish Date: 22 August 2024

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