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Hydraulic Diameter
Hydraulic Diameter is a core engineering term. Definition, usage notes, and a practical example.
Definition
Hydraulic diameter represents non-circular sections with an equivalent diameter for flow calculations.
Why it matters
It is used for ducts, rectangular passages, and channel calculations.
How it is used
In a design check, first define the relevant load, dimension, material, or flow condition. Then interpret this term by its role in the formula and compare it with limits.
Hydraulic diameter = 4 x area / wetted perimeter
Example
In a rectangular duct, hydraulic diameter uses area and wetted perimeter.
Related calculators and resources
Formulas
Hydraulic diameter = 4 x area / wetted perimeter