Laboratory and Numerical Study of Dynamics Salty Density Current in The Reservoirs

Document Type : Research Paper

Authors

1 Water resource expert Khuzestan Water and Power Authority

2 shahid chamran univercity of ahwaz

Abstract

     Since the characteristics of density current is affected by different parameters, the effect of discharge rate changes, gradient and the concentration of density current on speed of the forehead  and also the speed distribution in density current’s body have been investigated by physical and three-dimensional mathematical model (Flow-3d) in this research. For these purposes, different tests in the form of salty density current were done with three inflow discharge rates (0.7, 1 and 1.3 liters per second) and three different slopes (0, 1 and 2.2 percent). As well as to evaluate the effect of density changes on the flow characteristics, the concentration of 10, 15 and 20 grams per liter were used. In order to measure the speed of the forehead, velocity distribution in the body and its changes with flow, density and different slopes, video camera and ultrasound profiler speedometer were used in this study. Then, forehead speed and velocity distribution in the current’s body were achieved using six different turbulence models which are available on the software of “Flow-3D”. Comparing the results of physical and mathematical model showed that Eddy turbulence model and laminar flow mode have better accuracy in relation to other turbulent models. It should be noted that Reynolds number on experiments are at the range of  2000-4000.

Keywords


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Volume 40, Issue 2
September 2017
Pages 173-182
  • Receive Date: 28 November 2015
  • Revise Date: 25 September 2017
  • Accept Date: 30 April 2016
  • First Publish Date: 23 August 2017