# Bejan Number - Heat Transfer

Bejan number - heat transfer, abbreviated as Be, a dimensionless number, is the pressure drop along a channel of length.

## Bejan Number - Heat Transfer formula

\(\large{ Be = \frac{ \Delta p \; l^2 }{ \mu \; \alpha } }\) |

### Where:

Units |
English |
Metric |

\(\large{ Be }\) = Bejan number | \(\large{dimensionless}\) | |

\(\large{ l }\) = length of channel | \(\large{ft}\) | \(\large{m}\) |

\(\large{ \mu }\) (Greek symbol mu) = dynamic viscosity | \(\large{\frac{lbf-sec}{ft^2}}\) | \(\large{ Pa-s }\) |

\(\large{ \Delta p }\) = pressure drop | \(\large{\frac{lbf}{in^2}}\) | \(\large{Pa}\) |

\(\large{ \alpha }\) (Greek symbol alpha) = thermal diffusivity | \(\large{\frac{ft^2}{sec}}\) | \(\large{\frac{m^2}{s}}\) |