what’s causes laminar flow?



what’s causes laminar flow?

In: Physics

Surface tension. That’s a physical property of most liquids.

Viscosity. Most fluids have some attraction between adjacent molecules/atoms, they like to stick together to some extent. That thickness is called viscosity. Below a certain threshold (depends on the ratio of “inertial” to “viscous” forces, called the Reynolds number), the viscosity is enough to damp out any small wiggles in the fluid and everything flows nice and smoothly.

Above the threshold, viscosity isn’t enough to stop small disturbances from growing into big eddys and you get turbulent flow.