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Jane May 25, 2009 03:07

How to set a initial temperature and constant heat flux at same BC's??
i have set the wall boundary condition with heat flux w/m2 and i want to set the initial temperature for the same wall.

in my cooling simulation, the initial temperature of wall will decrease and the wall is depend on the heat flux.

however,for the boundary condition setting for wall, the thermal condition "temperature" is only can be set to constant. when i set it as a constant, my wall bc's just display a constant temperature in the result.

when i set the temperature at the wall in "initialize > compute from > wall".
the result still show the similar temperature for my wall boundary conditions.

Please give me any idea to solve the problem. Thank you

GS Gunasegarane March 20, 2010 09:36

How to set constant heat flux BC as well as initial temp
Hi Jane

Did you get any reply for your query on heat flux BC. I am also having the same problem of setting constant flux BC for a wall as well as the wall initial temperature. Since the temperature is set as constant in the BC it is showing constant temperature in the result. If i set it to zero, it is showing zero temp close to the wall. But I would like the wall to change the temperature as per the heat flux condition. If you have solved your case then pl help me out. If somebody have an idea how to overcome this problem pl do guide me. Thanks in advance

fluent87 April 16, 2013 09:03

have you ever been solve the case?
I've your some problem...

peppelmb October 21, 2015 04:49

Variable temperature
Does anyone know how to solve this problem? I need to put a variable temperature as boundary conditions, but I don't know hot to do it. I think that could be done by defining a UDF. Please somebody help me!

LuckyTran October 25, 2015 13:01

Do not confuse initial conditions with boundary conditions.

If you want to set an initial temperature profile with a constant heat flux boundary condition:

The initial conditions are handled in the solution initialization procedure. You do not apply initial conditions as a boundary condition.

If you need to specify a temperature profile as the initial condition then you should define a field function and patch that to the wall. Or you can use a fancy UDF.

The boundary condition should be the constant heat flux.

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