Chemical Engineering - Fluid Mechanics - Discussion

Derive the equation for velocity profile?

I think its turbulent.

As it is turbulent flow the velocity profile is nether parabolic nor linear. And as it flows with high velocity it velocity profile must be logarithmic.

U = u(max) + 2.5 u* log(y/R) so its logarithmic.

For turbulent its logarithmic.

And for laminar its parabolic.

Do we face linear velocity profile in any case? If yes, please give an example?

It should be parabolic.

It is logarithmic because it is U*logy, parabolic curve is for laminar flow in the distribution curve, there are basically 3 zones in the flow distribution for turbulent flow, 1 is a laminar flow curve which generally known as parabolic and the, 2 zone is of buffer zone in which fluid transfer from laminar to turbulent this point is the starting point phase of fluid, then 3 zones is known as logarithmic zone because at this the fluid generally converted into Laminar to turbulent so it is known as logarithmic curve (U proportional to log y), in this zone fluid has very low REYNOLDS NO.

Option D is the correct answer.

What about a laminar flow?

Super, thanks for the explanation.