Hydraulic Diameter Calculator
Calculate hydraulic diameter (D_h = 4A/P) for rectangular, circular, annular, and custom cross-sections
Hydraulic Diameter Calculator
D_h = 4A/P · A = cross-sectional area · P = wetted perimeter
Hydraulic Diameter D_h
0.3750 m
= 375.0 mm
Cross-Section Parameters
Area A
0.150000 m²
Wetted Perimeter P
1.6000 m
Formula
D_h = 4·(a·b) / (2·(a+b)) = 2ab/(a+b) = 2×0.3000×0.5000/0.8000
D_h = 4×0.150000/1.6000 = 0.3750 m
How to Use This Calculator
Enter your input values
Fill in all required input fields for the Hydraulic Diameter Calculator. Most fields include unit selectors so you can work in your preferred unit system.
Review your inputs
Double-check that all values are correct and that you have selected the right units for each field. Incorrect units are the most common source of calculation errors.
Read the results
The Hydraulic Diameter Calculator instantly computes the output and displays results with units. All calculations happen in your browser — no loading time and no data sent to a server.
Formula Reference
Hydraulic Diameter Calculator Formula
See calculator inputs for the governing equation
Variables: All variables and their units are labeled in the calculator interface above.
When to Use This Calculator
- •Use the Hydraulic Diameter Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations.
- •Use it during the design phase to rapidly iterate on parameters before running detailed finite element simulations.
- •Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility.
- •Use it to generate reference data for a technical report or presentation without manual computation.
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