CE5011 exam 2017 2018 – Saved
- The vertical sluice gate located in the rectangular laboratory flume passes a unit discharge q = 0.095 m3s-1m-1. A free discharge occurs under the gate with a hydraulic jump immediately downstream. Take section 1 to be located upstream of the gate, section 2 at the minimum depth downstream of the gate and section 3 at a location just downstream of the hydraulic jump. The sluice gate coefficient of contraction Cc may be taken as 0.62.
(a) Determine the gate opening (x) to give the unit discharge of 0.095 m3s-1m-1 when the upstream water depth (y1) is 420 mm.
(b) Calculate the maximum value of the wij‘watrel, depth (y3) in the flume that allows free discharge to occur under the gate. Determine the energy head lost in the hydraulic jump.
The conjugate depth equation for a hydraulic jump is:
= -1 (41+ 8Fr,’” – 1) Y 2
All symbols have their usual meaning.
(c) Calculate the specific energy head at each section and draw a labelled reasonably scaled diagram of the sluice gate, showing clearly the water surface profile and energy line. (4 marks)
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