Hydraulic Diameter Calculator

Calculate hydraulic diameter for non-circular cross-sections

Cross-Section Parameters

Shape Type

Width (inches)

Height (inches)

Hydraulic Diameter Formula:

Dh = 4 × Area / Wetted Perimeter

For circular pipe: Dh = D

Hydraulic Diameter

16.000"

Equivalent Round Diameter

18.280"

Cross-Section Area:288.000 sq inArea:2.00000 sq ftWetted Perimeter:72.000"Hydraulic Radius:4.000"

Aspect Ratio:2.00:1Compactness:0.698Reynolds @ 5 ft/s:547795

Compactness = 1.0 for circle

Shape-Specific Formulas:

• Rectangle: Dh = 2WH/(W+H)

• Circle: Dh = D

• Square: Dh = side

• Annulus: Dh = Do - Di

• Eq. Triangle: Dh = side/√3