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Interpolation Function with 2 arguments

Posted Apr 9, 2018, 12:48 p.m. EDT Fluid & Heat, Heat Transfer & Phase Change, Heat Transfer Version 4.4 3 Replies

Eminem Raj
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Hello people, I have a problem. So, I'm trying to enter Cp(specific heat) as a function of two variables-temperature and magnetic field. Cp as a function of T is accepted under the particular material properties. But when I enter 'Cp(T,H)' it turns orange and says H is an unknown variable.

I have defined H as a time dependent interpolation function under Global Definitions.

And for Cp, I have defined it as an interpolation function depending on 2 arguments(temp and mag. field). I've input a txt file for this purpose.

I have attached the figures for reference.

Please help

Attachments:

3 Replies Last Post Apr 13, 2018, 2:49 a.m. EDT
Sohan Birla
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Posted: 7 years ago Apr 12, 2018, 5:56 p.m. EDT

You are calling H intrplotation function which is the function of time as you defined. Threfore you need to type CP(T, H(t))

You are calling H intrplotation function which is the function of time as you defined. Threfore you need to type CP(T, H(t))
Eminem Raj
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Posted: 7 years ago Apr 13, 2018, 2:45 a.m. EDT

Thanks a lot Sohan sir.

It worked.

Is there any way to know how COMSOL interpolates?

Clearly there are some overlapping values for 0 & 5 tesla. But H is varied in time as per our interpolation. How does it pick values and how does it move from each time step? Can you please shed some light on this?

I've used the following format and values for Temp, H and Cp (notepad file attached). This isn't the complete data. The complete data is as shown in the COMSOL image-attached.

Thanks a lot Sohan sir. It worked. Is there any way to know how COMSOL interpolates? Clearly there are some overlapping values for 0 & 5 tesla. But H is varied in time as per our interpolation. How does it pick values and how does it move from each time step? Can you please shed some light on this? I've used the following format and values for Temp, H and Cp (notepad file attached). This isn't the complete data. The complete data is as shown in the COMSOL image-attached.
Eminem Raj
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Posted: 7 years ago Apr 13, 2018, 2:49 a.m. EDT

And also, is it not enough that I've entered the values in notepad for C as a function of T and H? Why do I have to define another function H with different values?

Is it considering the values in my notepad?

Please clarify

And also, is it not enough that I've entered the values in notepad for C as a function of T and H? Why do I have to define another function H with different values? Is it considering the values in my notepad? Please clarify

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