Hydraulic Diameter for Non-Circular Ducts
Calculates hydraulic diameter, average velocity, kinematic viscosity, and Reynolds number for rectangular ducts to determine flow regime.
📖 Need the theory? Read the methodology, assumptions, and equations in the full reference guide.
1. Define Input Parameters
2. Engineering Output
cross-sectional area (A)
- m²
- m²
wetted perimeter (P_w)
- m
- m
hydraulic diameter (D_h)
- m
- m
average flow velocity (V̅)
- m·s⁻¹
- m·s⁻¹
kinematic viscosity (ν)
- m²·s⁻¹
- m²·s⁻¹
Reynolds number (Re)
- –
- –
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Download Offline Excel CalculationContext & Assumptions
The hydraulic diameter allows engineers to apply circular-pipe correlations to non-circular ducts, which is essential for sizing ventilation systems, heat-exchanger channels, and reactor manifolds in process plants. It converts complex geometries into an equivalent pipe diameter for Reynolds number and pressure-drop calculations.
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