Flow over embankment gabion weirs in free flow conditions

In this study, a series of laboratory tests were performed to investigate the effects side ramp slope, crest length, and porous media properties on flow regimes, water-surface profiles, discharge coefficients, energy dissipation in embankment gabion weirs with upstream downstream slopes. 24 physical models solid three different upstream/downstream slopes (90°, 45° 26.5°) created. To complexity over porous-fluid interface through material, three-dimensional (3D) numerical simulations developed. simulation, standard k-ε turbulence model was utilized. A structured mesh domain used simulate model. Water surface profiles above for comparison between measured data. These comparisons helped determine variables simulations. Numerical simulation enables visualization streamlines around weirs. addition, mean stream wise velocity within structures obtained. showed that reduction slope face leads an increased curvature distribution exhibits non-uniform wavy shape due geometrical As move downstream, more affected by presence pores. The experimental results show decreasing slopes, from 90° 26.5°, decreased coefficients. However, all cases, lead greater coefficients than those similar For milder ratios (flow passing faces inlet discharge) nonlinearly. Moreover, increasing discharge, relative reduced up 45%