Hi All,
I am working on an experiment in which a PCM is impregnated inside metal foam voids. Hence its a metal foam-PCM composite. My experiment has two distinct zones. First is the zone where PCM stays as a solid and heated upto its melting point. In the second zone PCM becomes liquid and heat to 15 degrees above its melting point.
I was wondering which mode of heat transfer will be dominant in both cases. In the first case i guess there is no fluid so heat transfer will be by pure conduction. I am confused about the second case. What non-dimensional numbers should i use? Peclet, Rayleigh and Grashoff all look relevant. im confused?
Dear@Zahid Ahmed Qureshi. In the first stage l, the radiation heat transfer would also be significant due to very high temperaures.
Furter, in the second stage, conduction, convection and radiation, the three modes must present and be taken into consideration. And it would be free convection due to absence of some external force, hence Rayleigh no. and Grashoff no. should taken into account.
However, if the gap for convection is very small like in micron then space for microcurrents set up for convection would be small. Hence convection would me similar to conduction.
May be using both and comparing them if you want to know which one dominates, or reporting both (additive), depending on your research goal.
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