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"Unknown variable" for interpolation function when called in thermal expansion study in COMSOL 5.2

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Hi,

I am new to COMSOL. My work is basically on accelerated testing of PV modules. I wanted to do the fatigue study by using temperature cycle as defined by IEC 61215 standard.

I have constructed the cycle by using interpolation, and called the function as 'therm' with units of argument in 'min' and function in 'deg-C'. Attaching the screenshot (interpolation.jpg) for reference.

Now when I am calling this function as a 'model input' in the 'thermal expansion' study under the user defined temperature, it is showing 'therm' as unknown variable. Attaching the screenshot (unknown variable. png) for reference.

I have also tried inputting 'therm (t[min])' or 'therm(t), there it shows 'syntax error in expression'.

Am I making any fundamental mistake here. Kindly help me out on this. Thanks.


1 Reply Last Post 8 août 2016, 10:11 UTC−4

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Posted: 8 years ago 8 août 2016, 10:11 UTC−4
If the therm is for whole domain than you do not need to solve heat transfer node. In thermal expansion multiphysics coupling node directly type therm(t) in temperature input box.

If the therm is for whole domain than you do not need to solve heat transfer node. In thermal expansion multiphysics coupling node directly type therm(t) in temperature input box.

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