Question

What is Reynolds number?

Answer 1

The Reynolds number is an experimental number used in fluid flow to predict the flow velocity at which turbulence will occur. It is described as the ratio of inertial forces to viscous forces. For flow through a tube, it is defined by the relationship
$N=\frac{\rho vD}{\eta }$
where, $N$ = Reynolds number
$\rho$ = Density of the fluuid
$v$ = Velocity of the fluid
$D$ = Diameter of the tube
$\eta$ = Viscosity of the fluid