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Glossary · Friction & flow regimes
Reynolds Number
Represents the ratio of the inertial force to the viscous forced exerted on the fluid.
This dimensionless parameter is applied to characterize flow regime by quantifying the momentum of a fluid or the inertial forces compared to the internal friction or fluid viscosity.
At high Reynolds number, inertial forces dominate leading to turbulent flow, while at lower values signify that viscous forces are influential, resulting in smooth, laminar flow.
It is calculated using the expression:
Re = DV\rho/\muWhere:
| D | Pipe internal diameter |
| V | Fluid velocity |
| ρ | Fluid density |
| μ | Fluid viscosity |
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