OK..

Now the big question.. the flow parameter Re & thermal parameter Pr, how they connects to HEAT TRANSFER???

So for our help.. Mr. Nusselt has created Nusselt Number!!

The traditional dimensionless form **Nusselt number Nu**, which may be defined as the ratio of convection heat transfer to fluid conduction heat transfer under the same conditions.

Nusselt number Nu can be calculated as

Nu = X . Re^y.Pr^z