Reynolds number
E620784
The Reynolds number is a dimensionless quantity in fluid mechanics that characterizes the flow regime of a fluid, indicating whether it is laminar or turbulent based on the ratio of inertial to viscous forces.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Reynolds number canonical | 1 |
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf | dimensionless quantity ⓘ |
| affects |
boundary layer behavior
ⓘ
drag coefficient ⓘ heat transfer coefficients ⓘ |
| appliesTo |
external flows
ⓘ
flow over bodies ⓘ internal flows ⓘ pipe flow ⓘ |
| basedOn | ratio of inertial forces to viscous forces ⓘ |
| characterizes | flow regime ⓘ |
| classification |
high Reynolds number flow
ⓘ
low Reynolds number flow ⓘ |
| dependsOn |
characteristic length
ⓘ
dynamic viscosity ⓘ fluid density ⓘ fluid velocity ⓘ |
| dimension | dimensionless ⓘ |
| field | fluid mechanics ⓘ |
| formula |
Re = (v L) / ν
ⓘ
Re = (ρ v L) / μ ⓘ |
| governs | similarity of flows at different scales ⓘ |
| highReCharacteristic | inertial forces dominate ⓘ |
| introducedInField | hydrodynamics ⓘ |
| lowReCharacteristic | viscous forces dominate ⓘ |
| namedAfter | Osborne Reynolds NERFINISHED ⓘ |
| relatedTo |
Navier–Stokes equations
NERFINISHED
ⓘ
laminar flow ⓘ transitional flow ⓘ turbulent flow ⓘ |
| SIUnit | 1 ⓘ |
| symbol | Re ⓘ |
| transitionalRange | 2000 < Re < 4000 for pipe flow ⓘ |
| typicalLaminarThreshold | Re < 2000 for pipe flow ⓘ |
| typicalTurbulentThreshold | Re > 4000 for pipe flow ⓘ |
| usedFor |
distinguishing laminar and turbulent flow
ⓘ
model testing in wind tunnels ⓘ predicting onset of turbulence ⓘ scaling laboratory experiments to real systems ⓘ |
| usedIn |
aerodynamics
ⓘ
chemical engineering ⓘ heat transfer analysis ⓘ hydraulics ⓘ turbulence modeling ⓘ |
| usesParameter |
L (characteristic length)
ⓘ
v (velocity) ⓘ μ (dynamic viscosity) ⓘ ν (kinematic viscosity) ⓘ ρ (density) ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.