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The Heat capacity at constant pressure of materials is defined by interpolation function

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Hello, I am using interpolation functions to define the Heat capacity at constant pressure of materials. The specific heat capacity of a material varies with temperature. But the call to this function (heat_cp) always shows yellow and says: unknown variable heat_cp. However, I checked that the units of the function were J/(kg*K) and did not forget the definition. How can I correct this mistake. Any help would be helpful.


2 Replies Last Post 1 mar 2022, 20:20 GMT-5
Jeff Hiller COMSOL Employee

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Posted: 3 years ago 1 mar 2022, 12:05 GMT-5

Hello Haha,

If the error message says "unknown variable", that suggests to me that you may not have called the function with arguments, leading the software to think it is a variable instead of the function that it is.

Your function call should look something like this:

heat_cp(T)

if T is the temperature.

Best,

Jeff

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Jeff Hiller
Hello Haha, If the error message says "unknown variable", that suggests to me that you may not have called the function with arguments, leading the software to think it is a variable instead of the function that it is. Your function call should look something like this: heat_cp(T) if T is the temperature. Best, Jeff

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Posted: 3 years ago 1 mar 2022, 20:20 GMT-5

Hi Jeff Thank you for your suggestion. It helped.

Best regards to you.

Haha

Hi Jeff Thank you for your suggestion. It helped. Best regards to you. Haha

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