PERFORMANCE OF RUBBLE MOUND WEIR IN CONTROLLING STAGE-DISCHARGE, DISSIPATING MOMENTUM-ENERGY AND PURIFYING WATER

Abstract

 Hydrodynamic analysis was carried out to investigate performance of a rubble mound weir in controlling water level and discharge, impounding water, generating flow force, dissipating fluid momentum and energy and purifying water. A solid impermeable weir with the same dimension and scale was assumed as a reference case. Time-dependent behaviors of depth and discharge during a single-peaked flood event suggested that the rubble mound weir decreased the water level during the rising stage more than the impermeable weir. By analyzing momentum and energy balances, performances as a flow force controller and as an energy dissipater were compared between the rubble mound and impermeable weirs. Additionally, the pollutant removal rate was analyzed by assuming a primary reaction in the course of infiltration through the porous body.