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 gmoehl August 17, 2012 04:55

Problem with Field Function

Hallo,

I've got a coolingtube through which an air stream flows. This air stream is heated by an heat flux over the surface of the tube.
The problem is that I don't know the temperature of the incoming and the outgoing air. I' only given the masflowrate of the air and the middle temperature of the air calculated by the equation:

Tm=(Tout+Tin)/2

I've chosen a Mass Flow Inlet as boundary-type for the Inlet. Of course the program demands the Inlet Temperature. So I wondered wether it is possible to write a Field Function for the Inlet that gets the outlet Temperature and then iterates the Inlet Temperature?
The Formula is not difficult but how do I get the temperature from a different Boundary?

Claas

 rwryne August 17, 2012 08:38

Quote:
 Originally Posted by gmoehl (Post 377466) Hallo, I've got a coolingtube through which an air stream flows. This air stream is heated by an heat flux over the surface of the tube. The problem is that I don't know the temperature of the incoming and the outgoing air. I' only given the masflowrate of the air and the middle temperature of the air calculated by the equation: Tm=(Tout+Tin)/2 I've chosen a Mass Flow Inlet as boundary-type for the Inlet. Of course the program demands the Inlet Temperature. So I wondered wether it is possible to write a Field Function for the Inlet that gets the outlet Temperature and then iterates the Inlet Temperature? The Formula is not difficult but how do I get the temperature from a different Boundary? Thank you all in advance for your help, Claas
Use a report. Set up a report to get the (avg, min, or max, whichever you want) temperature on your outlet. You can then reference it in a field function by using \$<ReportName>Report. I.e. if you report is "Outlet Temperature" you can reference this in a field function using \$OutletTemperatureReport

 gmoehl August 18, 2012 04:17

Thank you very much for your help rwryne.
It's working

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