Experimentally Comparisons of the Effect of Porous Sheets and Porous Obstacles in Controlling Turbidity Current

Document Type : Research Paper

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Abstract

Turbidity currents are the main factors of sediment  transportation and deopsition in reservoirs. In this research, the effect of porous sheets and permeable obstacles in controlling the turbidity currents has been studied experimentally.  Plexiglas sheets with the thickness of 2 mm were used to build porous sheets and hollow plastic cubes were used for building porous obstacles with dimensions of 2.1 × 2.1 × 2.1 (cm). The surface porosity was assumed about 25% for the both models of obstacles. The experiments were performed in a slopping flume at the length of 10 m with three different slopes. During the expriments, the concentrations of the turbidity current at upstream and downstream of the porous sheet and the porous obstacle were measured using suction probes. In case of the porous sheet, the turbidity current entered the pores longitudinally, while in case of the porous obstacle, it entered the pores in two perpendicular directions. The result showed that in the case of utilizing porous obstacles, a rotational flow was formed as the turbidity currents entered in two perpendicular directions which increased the dissipation of the turbidity current’s energy in the porous obstacle application compared to the porous sheet application. Furthermore, by increasing the relative height of the obstacle in both zero-slope and non-zero slope cases the performances of the both porous obstacles and the porous sheet were increased. 

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References

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Water and Soil Science
Volume 27, Issue 1
June 2017
Pages 43-54

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