Ambient temperature

alpharays786

Hi all,

 

For a simulation that need to run in an ambient temperature e.g -18^oC.

Where should I setting this physic? at 'Nodal_Initial_Condition' temperature or 'absolute temperature offset' at Problem description?

 

Thank you

Regards

ydigit

Nodal Initial Temp would just be the 'starting' Tempertaure.

Offset would adjust all Temperature values entered in the input by the 'offset' value.

 

What you are most likely looking for is : Surface >Simple BC > Temperature BC Type > Flux > Convective heat  flux reference Temperature.

You would also need to specify a relevant Convective Heat Flux Coefficient.

acupro

I would also add that it depends what kind of analysis you want to perform.  If you want to perform a thermal analysis where you expect/want the temperatures to change as part of the analysis, you need to set appropriate boundary conditions.  If you only want to run a flow analysis - and assume the temperature is constant throughout - you need to define your material properties to be consistent with your desired operating temperature.

Altair Forum User

Hi acupro I Have a similar problem as you mentioned above. I  want to perform a thermal analysis where I expect/want the temperatures to change as part of the analysis. 

My boundary condition is Surface >Simple BC > Temperature BC Type > Value > 250 C

From the below picture it seems that the temperature is constant in the face throughout the simulation and it is not changing.

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ydigit

If you assign a boundary condition it is by default constant for that surface. In your case, if you expect to observe a part cooling, then probably nodal initial condition is what you should be assigning to this volume.