Thermal B.C at walls

January 23, 2004, 11:57

Hi everyone,

There is 5 options in thermal B.C at walls, do I have to choose only one of them or can I choose more than one if I know all the parameters?

In case I choose only one, say heat flux, does fluent take into consideration the default value, for the specified temperature for example, in the calculation?

Thank you so much.

January 26, 2004, 05:07

When setting a thermal boundary conditions you can only specify heat flux OR temperature. To set both would be to overconstrain the equations. If you set the heat flux the code should calculate the temperature and visa versa. For example, if you set the heat flux and the local velocity increases then the temperature at the wall may well drop due to increased convection.

Hope some of this helps

January 26, 2004, 19:52

or you could specify a heat transfer coefficient and an external temperature, in which case Fluent will calculate a wall temperature and a heat flux based on those boundary conditions.

January 27, 2004, 13:57

Thank you so much Andrew and Anton.

January 23, 2004, 11:57	Thermal B.C at walls	#1
Riham Guest Posts: n/a	Hi everyone, There is 5 options in thermal B.C at walls, do I have to choose only one of them or can I choose more than one if I know all the parameters? In case I choose only one, say heat flux, does fluent take into consideration the default value, for the specified temperature for example, in the calculation? Thank you so much.

January 26, 2004, 05:07	Re: Thermal B.C at walls	#2
Andrew Garrard Guest Posts: n/a	When setting a thermal boundary conditions you can only specify heat flux OR temperature. To set both would be to overconstrain the equations. If you set the heat flux the code should calculate the temperature and visa versa. For example, if you set the heat flux and the local velocity increases then the temperature at the wall may well drop due to increased convection. Hope some of this helps

January 26, 2004, 19:52	Re: Thermal B.C at walls	#3
Anton Guest Posts: n/a	or you could specify a heat transfer coefficient and an external temperature, in which case Fluent will calculate a wall temperature and a heat flux based on those boundary conditions.

January 27, 2004, 13:57	Re: Thermal B.C at walls	#4
Riham Guest Posts: n/a	Thank you so much Andrew and Anton.

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