3.2.25 cw_vatankhah_kouchakzadeh - Vatankhah-Kouchakzadeh friction factor

f = cw_vatankhah_kouchakzadeh(d,e,re)

Calculate the Vatankhah-Kouchakzadeh approximation of the Colebrook-White equation.

Arguments

d

Pipe internal diameter ().

e

Pipe effective roughness .

re

Reynolds number

Returns Darcy friction factor , dimensionless.

Possible Errors

Vatankhah-Kouchakzadeh diameter is <= 0

The given internal diameter of the pipe must be above zero.