Turbulent boundary layers [Fluid Mechanics #14]

[@Frostbyte-Game-Studio]

fantastic video please continue to make these

[@prof.vanburen]

Thanks! Definitely more to come

[@fluffiddy6515]

14:58 is the Reyneld Number ReL (rho*V*x)/mu where x is the length of the turbulent section?

[@dans7731]

Great video

[@prof.vanburen]

Thanks Dan!

[@olimolim7230]

The turbulent tuna was an awakening moment for me 😂

[@prof.vanburen]

Haha classic tuna

[@sudeephalder8792]

Sir, can you pl explain specifically exactly how the velocity difference can create vortices or circular motion through the angular momentum ???

[@prof.vanburen]

Good and complex question, understanding turbulence is no easy task.
Velocity difference, like in a boundary layer, leads to vorticity---and vorticity is the root of vortex structure. A boundary layer has vorticity from shear, however this is not the same as a vortex which requires fluid rotation (searching a parameter called the Q-criterion might be helpful here). However, when the shear in a boundary layer is disturbed either through physical impedance like roughness, or naturally occurring instability growth, it can cause this vorticity to become rotational and lead to vortex structure. These lead to things called hairpin vortices, and those eventually comprise wall-bounded turbulence.
Not sure if you find this helpful, this is just how I understand it!

[@sudeephalder8792]

It's helpful. Thanks 🙃