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Magnus Rohde May 19, 2003 03:33

thermal conductivity
During the simulation of heat transfer during laser-solid interactions I came to the result that for a given value of the thermal conductivity ( set by PRNDTL(TEM1)=-5.0 in Q1) the calculated temperature distribution did not correspond to this value but to a thermal conductivity which is orders of magnitude higher. I have checked that against results obtained with an other FE-package and also against experimental results. Are there any factors that I have missed?

John Ludwig, CHAM May 19, 2003 05:17

Re: thermal conductivity
Please contact CHAM User Support at, giving details of the PHOENICS version and attaching the Q1 and any geometry or ground files needed.

cham support May 22, 2003 07:36

Re: thermal conductivity
Your analysis is correct. The problem is that V3.4 erroneously uses (density*thermal conductivity) for the thermal conductivity in the TEM1 equation, if storage is NOT provided for the property material index, i.e. the PHOENICS whole-field variable PRPS has not been STOREd. This problem is not present in the later release, i.e. PHOENICS V3.5. The problem can be cured by activating storage of PRPS from the VR Environment under:

'Menu'>'Models'>'Solution control/Extra Variables'.

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