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Is there a possibility to couple 1 variable of a user-defined formula with 'ec' Physics computed values

Posted 21.02.2014, 08:42 GMT-5 Low-Frequency Electromagnetics, Materials Version 4.3b 5 Replies

Tanumay Karmokar
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Hello,
Greetings of the day!

I am trying to define a (user-defined) material. One of the properties of the material (e.g. Electrical Conductivity) is to be defined using a formula. One of the variables in this formula is required to be dependent on the Electric Field strength. Therefore, I want to couple the value of this variable in the formula with the Electric field values calculated in the 'Electric Currents (ec)' Physics computation. However, I am not able to accomplish this task.

Is there anyone who can please help me in understanding how can this idea be implemented using COMSOL
Many thanks (in advance)

Kind regards
Tanumay
5 Replies Last Post 20.08.2016, 07:16 GMT-4
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago 21.02.2014, 16:43 GMT-5

You can use any mathematical expression and thus all available variables in the material parameters to make the parameter depend on a field quantity.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
You can use any mathematical expression and thus all available variables in the material parameters to make the parameter depend on a field quantity. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Tanumay Karmokar
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Posted: 1 decade ago 22.02.2014, 05:49 GMT-5
Thank you Edgar,

However, I wanted to know how to do this in COMSOL. Could you please help me in understanding the procedure for doing this in COMSOL? The formula is as follows;
X=S*{exp [ (a*T)+(y*E) ] }

1) Values of all variables are known except for 'E', which is dependent on the Electric field that will be computed by the 'Electric Currents' Physics.
2) T=T2-T1 (T2 & T1 are defined in 'Parameters'. T1 is fixed, however there will be a 'Parametric Sweep' done to vary T2)
Thus we can say that the 'material property' X is dependent on both 'Temperature (T)' and 'Electric Field strength (E)'
3) I tried defining this formula, however, the formula is always seen in red. Does this mean that this is an error???

Please help!!
Many thanks!
Thank you Edgar, However, I wanted to know how to do this in COMSOL. Could you please help me in understanding the procedure for doing this in COMSOL? The formula is as follows; X=S*{exp [ (a*T)+(y*E) ] } 1) Values of all variables are known except for 'E', which is dependent on the Electric field that will be computed by the 'Electric Currents' Physics. 2) T=T2-T1 (T2 & T1 are defined in 'Parameters'. T1 is fixed, however there will be a 'Parametric Sweep' done to vary T2) Thus we can say that the 'material property' X is dependent on both 'Temperature (T)' and 'Electric Field strength (E)' 3) I tried defining this formula, however, the formula is always seen in red. Does this mean that this is an error??? Please help!! Many thanks!
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago 22.02.2014, 08:10 GMT-5

1. Replace E by the variable ec.????? you want to use from ec physics

2. Don't use short variable or parameter names like T, y, etc., they are often used internally by COMSOL, use something descriptive like my_temp

3. Take care about units and check the documentation for proper syntax.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
1. Replace E by the variable ec.????? you want to use from ec physics 2. Don't use short variable or parameter names like T, y, etc., they are often used internally by COMSOL, use something descriptive like my_temp 3. Take care about units and check the documentation for proper syntax. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Tanumay Karmokar
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Posted: 1 decade ago 22.02.2014, 10:05 GMT-5
Thank you very much Edgar
I shall implement your suggestions and let you know the outcome.

regards
Tanumay Karmokar
Thank you very much Edgar I shall implement your suggestions and let you know the outcome. regards Tanumay Karmokar
Harish Krishnappa
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Posted: 8 years ago 20.08.2016, 07:16 GMT-4
Even I am stuck with this problem. Were you able to find the solution?
Even I am stuck with this problem. Were you able to find the solution?

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