An Experimental Study of Roughness Elements to Design Fixed-Bed Hydraulic Model—A Step-by-Step Process and an Application in Vietnam

The calibration of the water level in a hydraulic model experiment is time-consuming task. In this study, authors proposed guide to adjust fixed-bed experiment, by establishing connection between increase (ΔZ) with other factors such as roughness diameter (d), density (s), and flow velocity (v). Based on results 105 experiments different d, s, v, study also suggested process design experiment. were used build for river section passing through Ialy hydropower plant Vietnam. showed that after 01 time implementation, was close observed level. differences calculated measured levels have been significantly reduced, from 0.027–0.036 m 0.003–0.008 m. This finding shows approach saves effort setting up