# Buckingham-Reiner equation (Darcy friction factor for laminar flow)

## Description

An exact description of friction loss (Darcy Weisbach equation) for Bingham plastics in fully developed laminar pipe flow was first published by Buckingham. His expression, the Buckingham-Reiner equation, can be written in a dimensionless form as shown in this equation.

Related formulas## Variables

f_{L} | Turbulent flow friction factor (dimensionless) |

Re | Reynolds number (dimensionless) |

He | Hedstrom number (dimensionless) |

f | Laminar flow friction factor (dimensionless) |