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Temperature Dependence / Material Properties

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Hi All,

I notice that COMSOL has several built in materials with properties defined as a function of temperature (or any other input variable for that matter).

As an example, in Laminar Flow physics, the fluid density can often be found as rho(T[1/K])[kg/m^3], indicating a function of temperature.

I was wondering if there is any way to see what sort of function is being used to define density via temperature?

I am aware you can always input a user defined density, and even your own temperature dependent density function. But I was curious if there is any way to see what COMSOL is doing behind the scenes.

Thanks.

2 Replies Last Post 26.05.2015, 18:07 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 9 years ago 26.05.2015, 14:39 GMT-4
Hi

if you go deeper into the material node sub-nodes you will find he equations and you might even plot them with a click, under properties you will often find also the references for these materials.

However, as usual with material properties there are often quite some dispersion between them, as many material have properties that depend strongly on their machining history, their temperature treatments and usage, so what I usually do is to build my own "material" data base, each time I need a new material I copy it and deposit it in my "private DB, after having checked that the data corresponds at best to the one I get from my supplier.
The only caveat, your private material DB is under the "C:/Users/... /.comsol/vnn/material" directory, that I often delete (at least for each new version installed), so BEFORE you must copy the file over to the new directory ;)

--
Good luck
Ivar
Hi if you go deeper into the material node sub-nodes you will find he equations and you might even plot them with a click, under properties you will often find also the references for these materials. However, as usual with material properties there are often quite some dispersion between them, as many material have properties that depend strongly on their machining history, their temperature treatments and usage, so what I usually do is to build my own "material" data base, each time I need a new material I copy it and deposit it in my "private DB, after having checked that the data corresponds at best to the one I get from my supplier. The only caveat, your private material DB is under the "C:/Users/... /.comsol/vnn/material" directory, that I often delete (at least for each new version installed), so BEFORE you must copy the file over to the new directory ;) -- Good luck Ivar

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Posted: 9 years ago 26.05.2015, 18:07 GMT-4
Ah, it was all right there in front of me. Thanks so much for the reply and your help!

Sanjin
Ah, it was all right there in front of me. Thanks so much for the reply and your help! Sanjin

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