A recent question about Phase Change materials....

If you are interested in Phase Change in building components the simulation tool
ESP-r has in-built methods for representing PCM with different performance
characteristics (and if you do not like the in-built methods you can add a
new method).

The ESRU group in Glasgow have past and present PhD working on this topic
who might be able to help. Note that manufacturers do not always publish the
full set of properties of PCM that are required for simulation but you might be lucky.

Regards, Jon Hand, ESRU