Investigating the effect of flow Density containing cohesive sediment on discharge coefficient of bottom intake with porous media

Water diversion from river for agriculture or industry based on gravity is possible according to different methods where using porous media is one of its methods. It is necessary to study the water diversion in such flows because there is sediment in water flow in the nature. Different methods such as: porous media grain size, cohesive sediment density and various water discharging were studied in this research by making experimental model. The obtained results show that discharge coefficient in D50 = 16.5 mm in discharge 20.7 lit/s with 1.5, 3, 6.5 and 8 gr/lit density are 0.038, 0.035, 0.034 and 0.033 respectively. Reducing the flow velocity in porous media is because of increasing in density which is a reason of reducing in discharge coefficient. The discharge coefficient for 3 gr/lit density in discharge of 20.7 lit/s for the D50, 11.5, 16.5 and 25 mm are 0.025, 0.035 and 0.042. This is happened because of higher porosity in D50 = 25 mm than D50 = 16.5 mm and D50= 11.5 mm. it was observed that in lower discharges, discharge coefficient changes are more than inlet discharge but it is stable by increasing the inlet discharge. By analyzing the obtained data and using dimensional analyzing and multivariate regression, relationships to estimate discharge and discharge coefficient were proposed for this intake