Reynolds number is a dimensionless quantity used in fluid mechanics to characterize the flow of a fluid. It is a measure of the ratio of the inertial forces...
Reynolds number is a dimensionless quantity used in fluid mechanics to characterize the flow of a fluid. It is a measure of the ratio of the inertial forces acting on a fluid particle to the viscous forces acting on the fluid particle.
Formula:
where:
Re is the Reynolds number
ρ is the density of the fluid
v is the velocity of the fluid
L is the characteristic length scale of the flow
μ is the viscosity of the fluid
Interpretation:
Reynolds number (Re) greater than 2000 indicates that the flow is turbulent.
Reynolds number (Re) between 200 and 4000 indicates that the flow is transitional.
Reynolds number (Re) less than 200 indicates that the flow is laminar.
Examples:
In water flow, the Reynolds number is typically between 200 and 400.
In air flow around a wing, the Reynolds number is typically between 1000 and 2000.
In a pipe flow, the Reynolds number is typically between 100 and 1000