A Dam Spillway Model Using End Sill

This research focuses on the development of a hydraulic model of energy dissipator with segmented end sill on the dam spillway as a modification of the standard United States Bureau of Reclamation (USBR) Type III design. By using Froude similarity analysis at 1:100 scale and a Froude number range of 13–25, this study compares the performance of the standard design (Configuration A) with a modification by using a two-segment zigzag pattern segmented end sill (Configuration B). The results show that Configuration B achieves a specific energy reduction of up to 15- 23% higher than Configuration A across all tested discharge ranges (9–22 l/s). The segmented end sill causes the increase of turbulence, the expansion of the vortex area, a more even distribution of energy, and then the reduction of the potential damage in the dam downstream. This research provides an efficient and economical design alternative for improving the safety of hydraulic structures in dams with high supercritical flow conditions.