froude {rivr} | R Documentation |
Froude Number
Description
Calculate the Froude Number.
Usage
froude(Q, g, A, DH)
Arguments
Q |
Flow rate [ |
g |
Gravitational acceleration [ |
A |
Flow area [ |
DH |
Hydraulic depth [ |
Details
The Froude number is a dimensionless measure of bulk flow characteristics that represents the relative importance of inertial forces and gravitational forces. For open channel flow, the Froude number of open channel flow is defined as
Fr = \frac{v}{\sqrt{gD_H}}
where v = \frac{Q}{A}
is the flow velocity, g
is the gravitational
acceleration and D_H
is the hydraulic depth. The Froude number is related
to the energy state of the flow and can be used to identify flows as
either supercritical (Fr < 1
) or subcritical (Fr > 1
).
Value
The Froude Number (dimensionless).
Examples
froude(250, 32.2, 171, 1.71) # subcritical flow
froude(250, 32.2, 57.9, 0.579) # critical flow
froude(250, 32.2, 45, 0.45) # supercritical flow
[Package rivr version 1.2-3 Index]