The Characteristic of Critical Flow on Sluice Gate

Abstract

The objective of this research is to analyse and to determine based on experiment relation among outlet depth of sluice gate, a, downstream, h2 and upstream depths, h1 as well as to determine the length of eddy phenomenon, Ld counted form sluice gate and its relation with discharge, Q. The research was conducted in Hydraulics Engineering Laboratory using several apparatus provided ini in State Polytechnics Kupang. Generally speaking, correlation among all variables used and analysed in this experiment had significant relationship, except between h0 and Q for a = 0,20 cm (R2=0.090), a = 0,50 cm (R2=0.436), h2 and Q for a = 0,20 cm (R2=0.046) and a = 0,40 cm (R2=0.289). the relatively small correlation value can be introduced by human or devices error during experiment. On the other hand, the highest correlation value was found between Ld and Q for a = 0,30 cm (R2=0.988). Curve shows that Q is in line with other three variables, namely Ld, h0, h1 and h2. Hence, the bigger the discharge, Q, the bigger Ld, h0, h1 and h2. By using upstream depth, h1 critical flow coefficient, ccr can be determined. In addition, critical depth, hcr lenght of eddies, Ld can be determined.