Equation of Hydraulic Jump Length in Front of Sluice Gate using Baffle Block and Sill as Energy Reducer

While the sluice gate is operated, a hydraulic jump always occurs in front of the gate. The formula for the length of the hydraulic jump in front of the sluice gate has not yet been determined exactly. The length of a hydraulic jump in a rectangular channel can be estimated using the following empirical equation. This research is development from previous researchers (Sunik, 2019). Running model test was carried out 270 times with detail as 71 times for cubic baffle block (K1, K2, K3) and 199 times for trapezoidal (T1, T2, T3, T4, T4A, T4B, T4C, T4D). The aim of this research is to determine the length of a hydraulic jump that occurs in a model test channel using sluice gate while additional structures as baffle blocks and sill installed at a certain distance from the sluice gate. The research result show that equation model for hydraulic jump length based on the best regression curve (close to 1) obtain Lj = y₁ (30.166x² + 10.854x + 7.0963) (trapezoidal baffle block (T4C)); as function Lj = y₁ (30.166 (f (h,w))² + 10.854 (f (h,w)) + 7.0963) , R² = 0,9887x represent the Froude number which is the beginning of a hydraulic jump.