Even at very high Reynolds numbers, the thin boundary layers remain as a result of viscous forces.

A large Reynolds number indicates that viscous forces are not important at large scales of the flow.

It may be regarded as proportional to gravity forces divided by viscous forces.

As for a particle in the fluidic flow, the viscous force is:

At the same time, viscous forces cause the molecules of the fluid to resist separation.

Stokes Flow, in which the viscous forces are much greater than inertial forces.

This represents the ratio of inertial to viscous forces in the flow.

Once the structure has been broken, the particles move with the liquid under viscous forces.

The Reynolds number is the ratio of inertia forces to the viscous forces in the flow.

Reynolds number is the ratio of inertial forces to viscous forces.