# Bingham Number

Bingham number, abbreviated as Bm, a dimensionless number, is the ratio of yield stress to visvous stress.

## Bingham Number formula

\(\large{ Bm = \frac{ \tau_y \; l }{ \mu\; v } }\) |

### Where:

Units |
English |
Metric |

\(\large{ Bm }\) = Bingham number | \(\large{dimensionless}\) | |

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

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

\(\large{ v }\) = velocity | \(\large{\frac{ft}{sec}}\) | \(\large{\frac{m}{s}}\) |

\(\large{ \tau_y }\) (Greek symbol tau) = yield stress | \(\large{\frac{lbf}{in^2}}\) | \(\large{Pa}\) |

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