Which Heat transfer coeffcient to use?
 

Hi folks:
Lets say we simulated a turbulent pipe flow by using standard k-epsilon model with one of the wall function (lets say standard wall function). Now we need the heat transfer coeffcient on the pipe surface as output from this simulation. In FLUENT under wall fluxes menu there is "surface heat transfer coefficient" and another one called "wall function heat transfer coeffcient". My questions are:
(1) which heat transfer coefficient (from the above 2) I should take as output from FLUENT?
(2) Lets say another person did the simulation of the outer domain of the pipe, in that case if he wants to give me the heat transfer coefficient which one will he give to me?
Thank you guys.
T

Hi!

the "wall function HTC" is calculated directly with the law of the wall. This is described in the Fluent manual as well.

Use the "surface HTC" - this one is calculated with the heat flow and the reference temperature. So you have to set the reference temperature as your fluid temperature.

Best wishes
Ralf