# Stanton number

The Stanton number, St, is a dimensionless number that measures the ratio of heat transferred into a fluid to the thermal capacity of fluid. The Stanton number is named after Thomas Edward Stanton (1865–1931).[1] It is used to characterize heat transfer in forced convection flows.

$\mathrm{St} = \frac{h}{G c_p} = \frac{h}{\rho u c_p}$

where

It can also be represented in terms of the fluid's Nusselt, Reynolds, and Prandtl numbers:

$\mathrm{St} = \frac{\mathrm{Nu}}{\mathrm{Re}\,\mathrm{Pr}}$

where

The Stanton number arises in the consideration of the geometric similarity of the momentum boundary layer and the thermal boundary layer, where it can be used to express a relationship between the shear force at the wall (due to viscous drag) and the total heat transfer at the wall (due to thermal diffusivity).

## References

1. ^ The Victoria University of Manchester’s contributions to the development of aeronautics
2. ^ Bird, Stewart, Lightfoot (2007). Transport Phenomena. New York: John Wiley & Sons. p. 428. ISBN 978-0-470-11539-8.