Siphon spillway: discharge–head relation Let a be the flow area at the throat and H be the effective head. Cd denotes the coefficient of discharge and g is gravitational acceleration. Choose the correct proportional form for the discharge through a siphon spillway.
Mechanical Engineering
Hydraulics and Fluid Mechanics
Difficulty: Medium
Choose an option
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ACd × a × √(2g) × H
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BCd × a × √(2g) × H^(3/2)
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CCd × a × √(2g) × H^2
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DCd × a × √(2g) × H^(5/2)
Answer
Correct Answer: Cd × a × √(2g) × H^(3/2)
Explanation
Concept/Approach
- For free-flow (weir-like) siphon action, discharge varies as area × velocity with velocity ≈ √(2gH) and effective head dependence H^(3/2) for weir-type flow.
RelationQ = Cd × a × √(2g) × H^(3/2) (up to geometry-dependent constants).
Final AnswerCd × a × √(2g) × H^(3/2)