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3x3 output properties

Posted 28.04.2011, 05:27 GMT-4 Materials, Parameters, Variables, & Functions Version 4.0 4 Replies

LiWah Wong
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hey people

Good day!
I have a 3x3 output property, namely {kappa11,kappa12,kappa13,kappa21,kappa22,kappa23,kappa31,kappa32,kappa33}, as per definition in the 'variable' columm of 'Materials', I would like to split them into 9, and define each of them under local 'variables', obviously I do not get the syntax correct therein I have issues of getting the correct unit for some relevant variables.

So, I tried 'kappa11', 'kappaxx', '{kappa11}'... none of them works... can someone help?

Many thanks!!!!!

regards
Liwah
4 Replies Last Post 28.04.2011, 08:16 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago 28.04.2011, 05:45 GMT-4
Hi

Comsol v4.1 does not allow sets "{}" apart for Parameters today, I have heard they are working on improving this

You need to go item by item

--
Good luck
Ivar
Hi Comsol v4.1 does not allow sets "{}" apart for Parameters today, I have heard they are working on improving this You need to go item by item -- Good luck Ivar
LiWah Wong
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Posted: 1 decade ago 28.04.2011, 06:00 GMT-4
Hi Ivar

thanks a lot for the prompt reply.
so, under mod1.var1 how should I define a permeability (kappa) in x-direction, y-direction and z-direction, seperately?
I understand from your reply that I have to take the whole 3x3 mat1.def as per following:

{kappa11,kappa12,kappa13,kappa21,kappa22,kappa23,kappa31,kappa32,kappa33}

into mod1.var1? if thats the case, how should I give a name to the variable? it doesnt allow a {} in the name, but when I tried out with others i.e. kappa11, I did not get the unit I want, which is m^2...

Hope that my reply is not too confusing... many thanks in hearing you back again :)

regards
Liwah
Hi Ivar thanks a lot for the prompt reply. so, under mod1.var1 how should I define a permeability (kappa) in x-direction, y-direction and z-direction, seperately? I understand from your reply that I have to take the whole 3x3 mat1.def as per following: {kappa11,kappa12,kappa13,kappa21,kappa22,kappa23,kappa31,kappa32,kappa33} into mod1.var1? if thats the case, how should I give a name to the variable? it doesnt allow a {} in the name, but when I tried out with others i.e. kappa11, I did not get the unit I want, which is m^2... Hope that my reply is not too confusing... many thanks in hearing you back again :) regards Liwah
LiWah Wong
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Posted: 1 decade ago 28.04.2011, 07:17 GMT-4
Hi Ivar

I try to understand your workaround better, so these are what I am doing right now:

1. I have 7 geological layers (domains)
2. I define a new 'material' for each of them, so I have 8 materials in total (including a 'water' for all 7 domains)
3. for each 'material', I assign 'material contents' i.e. heat capacity, thermal conductivity, permeabiliy... and assign to a domain, respectively
4. under 'darcy's law material model', I assign 'hydraulic conductivity' i.e. kappa*rho*g_const/mu

I hope I am on the right track, one thing that is bothering me is the orange-colored-fonts... indicating that I have wrong units...

Many thanks again for your time!!

regards
Liwah
Hi Ivar I try to understand your workaround better, so these are what I am doing right now: 1. I have 7 geological layers (domains) 2. I define a new 'material' for each of them, so I have 8 materials in total (including a 'water' for all 7 domains) 3. for each 'material', I assign 'material contents' i.e. heat capacity, thermal conductivity, permeabiliy... and assign to a domain, respectively 4. under 'darcy's law material model', I assign 'hydraulic conductivity' i.e. kappa*rho*g_const/mu I hope I am on the right track, one thing that is bothering me is the orange-colored-fonts... indicating that I have wrong units... Many thanks again for your time!! regards Liwah
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago 28.04.2011, 08:16 GMT-4
Hi

I'm no longer sure i understand you, now. If you have a material per domain, you define your values in the material db section that is the simplest, as then COMSOL looks after to map hem correctly to the different BCs

By the way update t latest version, you will go far quicker to set up your models

--
Good luck
Ivar
Hi I'm no longer sure i understand you, now. If you have a material per domain, you define your values in the material db section that is the simplest, as then COMSOL looks after to map hem correctly to the different BCs By the way update t latest version, you will go far quicker to set up your models -- Good luck Ivar

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