To model PCM hysteresis in EnergyPlus, what are the high/low temp difference of freezing/melting curves?

asked 2019-04-26 11:07:30 -0600

andresgallardo
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updated 2019-04-27 15:56:06 -0600

__AmirRoth__

4446 ●5 ●17 http://bleedinggreenna...

I read the EnergyPlus input output reference to see what are the inputs for modeling PCM hysteresis, but I can't understand what is the input for Low Temperature/ High Temperature Difference of Melting / Freezing Curve. Can someone explain in a graphic way what these fields mean? Thanks in advance for your help.

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I am looking for the same information. Can anyone help, please. Your cooperation is highly appreciated. Thank you.

ZeyadAmin ( 2019-10-07 21:26:35 -0600 )edit

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answered 2020-02-17 15:03:32 -0600

Fan
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I think I have figured out what these mean. If we look at the phase transmission in the following picture(A heat flux-temperature curve, and it could also be viewed as a Cp-Temperature curve), we will get what these inputs mean. Btw, Enthalpy-temperature curves could be calculated by integrating the Cp-Temperature curve using the following Equations. image description

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Thanks for taking the time to explain this. Can you be more clear, what is Exo and Endo in the graph? In the picture you sent, what are the inputs for Low Temperature/ High Temperature Difference of Melting / Freezing Curve? It's still not clear for me.

andresgallardo ( 2020-02-18 08:59:02 -0600 )edit

Endo is endothermal. Exo is exothermal. The low temperature difference is the temperature difference between the melting/freezing onset point and peak point, and high temperature is the difference on the other side of the peak..