Deriving Discharge Expression for Broad Crested Weir Model

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The discussion focuses on deriving a discharge expression for a broad crested weir using the Buckingham Pi theorem. It emphasizes that the discharge (Q) cannot be a repeating variable since it is dependent on other variables. Instead, the repeating variables should be the spillway head (H) and gravitational acceleration (g). Participants clarify the relationship between discharge, spillway head, and height, confirming the approach to the problem. The conversation centers on the correct application of dimensional analysis in fluid mechanics.
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Homework Statement


A broad crested weir model is designed to study the discharge per meter of the prototype. Derive an expression for this discharge using the Buckingham Pi theorem. Assume that the overflowing water sheet is thick so that the surface tension and thus viscosity of the fluid can be neglected. The equation of discharge (Q) for a weir has related with a function of spillway head (H), the gravitational acceleration (g), and the spillway height (h)

Homework Equations

The Attempt at a Solution



in this question , Q (discharge ) can't be chosen as repeating variable , right ? the repeating variables should be H and g , Am i right ? [/B]
 
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since Q is the dependent variable , am i right ?
 

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