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Pipe Flow Reynolds Number Calculator

Computes the Reynolds number for flow inside a pipe to classify the flow as laminar, transitional, or turbulent. Essential for friction factor selection, heat transfer design, and mixing analysis.

Fluid Velocity (m/s)

Pipe Diameter (m)

Fluid Density (kg/m³)

Dynamic Viscosity (Pa·s)

Fill in the required fields to see your result.

Fluid Mechanics

Manning's Roughness Flow Calculator

Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.

Hydraulic Radius (m)

Channel Slope (m/m)

Manning's Roughness Coefficient

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Key differences

	Pipe Flow Reynolds Number Calculator	Manning's Roughness Flow Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	4	3
Result	Reynolds Number	Flow Velocity (m/s)
What it does	Computes the Reynolds number for flow inside a pipe to classify the flow as laminar, transitional, or turbulent. Essential for friction factor selection, heat transfer design, and mixing analysis.	Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.