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May 1, 2012 7:49pm UTC

Error: Unknown function

I get error message:

Unknown function.
- Name: mat1.ref.rho

There's model in COMSOL Heat Transfer module library named circuit_board_nat_3d. It has a function which calculates density changes due to temperature and pressure (function is described as rho_ref in "Definitions>variables" and used in "Volume force" node).
In my model volume force is described the same as in turorial model, the function also is the same, but when I try to compute, solver leads to error! What's wrong? Why solver can't understand this function if in tutorial model it's ok?

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May 2, 2012 9:29pm UTC in response to Zydrius Zyrius

Re: Error: Unknown function

Hi

in v4.2 there is something calle "materials.rho" (check carefully the doc) for a generic naming, also (or only?) for data not used by present physics.
going after the direct "tag" names is error prone as you have experienced. Normally you use physics.rho where physics is solid, or ht or ...

--
Good luck
Ivar

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