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how to simulate effect of Phase change mateirals

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05-15-2013 03:04 AM

how to simulate effect of Phase change mateirals?

 

this software capable to simulate PCM effect ?

any ideas?

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Re: how to simulate effect of Phase change mateirals

05-15-2013 08:41 AM in reply to: Ahvz

I think a limited capability of cavitation is available, wherein only the regions of smaller vapor bubbles are realized in the regions of cavitation, instead of large regions of vapour. You may want to understand its caveats fully before venturing into it.

 

OJ

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Re: how to simulate effect of Phase change mateirals

05-15-2013 09:19 AM in reply to: OmkarJ

thank you for the reply,
is this only solution ? I mean, other methods can not be apply for the PCM effect?
such as enthalpy method and so on

regards,

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Re: how to simulate effect of Phase change mateirals

05-17-2013 10:58 AM in reply to: Ahvz

I am also having issues attempting to perform a rough simulation of PCM (phase change materials) for thermal storage.  Maybe I can piggyback on this thread with more specifics.

 

Specifically I am trying to approximate it as a solid that has a piecewise-linear specific heat that makes a large jump for about 1 degree to account for the latent heat of fusion (melting energy).  The area under the specific heat curve I think should equal the heat of fusion.  For example - a type of paraffin has specific heat of about 2 J/g-K as solid and liquid, but 200 J/g heat of fusion at 37 C.  So I bump up the specific heat from 37 to 38 degrees to 200 J/g-K.

 

However, this just isn't working - when I add heat at a constant rate, the temperature keeps rising linearly, even though it should "pause" as it reaches the melting temperature.    Many time steps are happening in the appropriate temperature area, so I'm not skipping past it.

 

Has anyone else had this problem, or can anyone at Autodesk explain why this wouldn't work?

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Re: how to simulate effect of Phase change mateirals

05-17-2013 11:08 AM in reply to: nhahn

Nevermind - problem solved - need to change the Material Environment Reference from FIXED to VARIABLE.

 

Behaves as expected now.

 

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Re: how to simulate effect of Phase change mateirals

05-17-2013 12:52 PM in reply to: nhahn
good to hear that!,

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Re: how to simulate effect of Phase change mateirals

05-17-2013 03:11 PM in reply to: Ahvz
I think you do not consider hystersis effect of the PCM. ofcourse, it depend to the accuracy that you need regard to your model...