Document Type : Original Manuscript

Authors

1 Department of Civil Engineering, Ghirokarzin Center, Firoozabad Branch, Islamic Azad University, Firoozabad, Iran.

2 Department of Civil Engineering, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran.

3 Department of Water Engineering, College of Agriculture, Isfahan University of Technology, Isfahan, Iran.

Abstract

The density current, as a part of the gravity currents, is the flow of one fluid within another caused by the density difference between two fluids. The density current consists of the nose, head, and body regions within the ambient fluid. In the present study, a flume with 8m length, 35cm width, and 40cm height was used. The experiments were performed in 28 different states by changing the bed slope, density, and discharge. The results indicated that by increasing the bed slope, the concentration of the density current decreased by 12% and 19% after continuous and local narrowing, respectively, compared to the non-narrowing state. Further, the entrainment ratio increased by narrowing the flume wall, as the Richardson number decreased by 80% and the entrainment ratio increased by 5 times after narrowing. In addition, the profile formation pattern of the current velocity and concentration enhanced by increasing the inlet density and the pattern indicated more scattering in the jet region compared to the wall region.

Keywords

Main Subjects

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