Graetz number

The Graetz number (Gz) is a dimensionless number that characterises laminar flow in a conduit. The number is defined as:

$Gz={d_i\over L}RePr$

where

d_i is the internal diameter

L is the length

Re is the Reynolds number and

Pr is the Prandtl number.

The quantity is named after the physicist Leo Graetz.

See also: Graetz number, Dimensionless number, Leo Graetz, Prandtl number, Reynolds number