مهندسی منابع آب (Apr 2020)
Laboratory investigation of the effect of thickness and two porous obstacles with a spacing in the Control the Turbidity Current
Abstract
In the present study, a laboratory comparison of increasing the number of porous obstacle rows and two porous obstacles with a distance of one meter is considered as a permeable obstacle for controlling turbidity current in different heights. Plastic cubes with dimensions of 2.1 (cm) with surface porosity of 25% have been used. The flume slope range was ± 2.5%, a length of 10, a width of 0.3 and a height of 0.45 m. The flow rate was 0.7 L/s and the input concentration was 20 g/L. The results of the investigations showed in the porous obstacle with the simultaneous flow of condensate in two directions perpendicular to each other, the flow lines encountered in the porosity and by creating a flow in porosity, cause more depletion of the energy of the current flow from within would be. The use of two obstacle rows reduces the height of the obstacle to control the current flow. Also, in the case of two obstacles with different heights, obstacle with higher elevations initially causes more deformation of the current. In steady state, due to the increase in the momentum of the flow, a greater part of the sediment passes through the first obstacle, which makes the effect of the second obstacle more effective in controlling the current flow in this state than the non-slope state. Also, with increasing number of rows, the performance of the porous obstacle increases and the performance of the two obstacles is longer than the thickness of the performance
