Time-mean Nusselt Number
 

Dear All,

Im looking for a suggestion on how to do this in the best way:

I would like to calculate time-mean Nusselt number but I do not trust pre-defined Nu# in fluent. ( I am solving radiation as well as convection and the value for total heat transfer coefficient accounts for both)

I would like to calculate Nusselt number from temperature gradient and I know there is a UDF for that purpose.
However, how would it be possible to calculate the time-mean temperature gradient?

I also dont think I can use custom field function for this purpose since it wont be possible to get the time-mean value.

Any suggestion would be great.

Cheers
Negin