# Stanton Number

## Description

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). It is used to characterize heat transfer in forced convection flows.

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).

## Variables

St | Stanton number (dimensionless) |

h | convection heat transfer coefficient (W/m^{2}*K) |

ρ | density of the fluid (kg/m^{3}) |

u | speed of the fluid (m/s) |

c_{p} | specific heat of the fluid (J/K*kg) |