Calculate the Froude number for fluid flow in open channels or ship resistance.
Flow Parameters
Dimensionless Results
Enter velocity and length
About this calculator
Quick Reference
FrFroude Number
vFlow Velocity
g9.80665 m/s²
LCharacteristic length
Overview
The Froude number (Fr) is a dimensionless value used in fluid mechanics to characterize the ratio of inertial forces to gravitational forces. It determines if a flow is subcritical or supercritical.
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Pro Tips
Fr < 1: Subcritical flow (slow and deep).
Fr = 1: Critical flow.
Fr > 1: Supercritical flow (fast and shallow).
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Fun Facts
"William Froude originally used this number to predict the resistance of ships moving through water."
"The 'hydraulic jump' occurs when a flow transitions from supercritical to subcritical."
"Froude number is vital for designing spillways, bridges, and canals."
