Chemical Engineering - Heat Transfer - Discussion

Conduction occurs in the buffer zone for a fluid flowing through a heated pipe only when the Prandtl number is greater than 0.6. The Prandtl number is a dimensionless quantity that characterizes the ratio of momentum diffusivity to thermal diffusivity.

A Prandtl number greater than 0.6 indicates that momentum diffusivity is greater than thermal diffusivity, which means that the fluid is more likely to transfer heat by conduction than by convection.

Pr>1: Viscous sub-layer.
Pr>0.6: Buffer zone.
Pr<0.6: Turbulent core.

I think the right answer is d =1.

Option D - 1 is the right answer.

Option C is the correct answer.

I agree 0.1 this right answer.

I think D is the right Answer.

What about C? Please explain.