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Two Phase Fluid Flow - Polymer Calendaring: Unknown Error

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Greetings -

I am working with the Phase Field branch of Laminar Two-Phase Flow to model the nip region of a calendaring operation (two large rollers squeeze a fluid through a small gap to create a uniformly thick sheet). The two phase model is used to provide a Moving Wetted Wall boundary condition where the calendared fluid detaches from the calendared sheet (two phases are a polymer fluid and air). The rollers are spinning at some velocity and the sheet has some contact angle - currently set by myself - as it releases from the roller.

The problem: The laminar two-phase flow, phase field physics defaults to a time-dependent solver which I do not necessarily need. But, starting with this solver, it goes through a Phase Initiation step without issue and then moves on to the time-dependent solver. Before it can take any time steps I get the error: Undefined value found. This would seem simple, but the "detail" it provides says: "Undefined value found in the constraint residual vector: NaN of Inf in vector." Can anyone help resolve what this might be referring to or how I can find out what is not defined? I'm not sure where to begin troubleshooting...

The error handling/messaging in COMSOL has never impressed me, but this one is especially poor.

Thanks in advance! Mark

1 Reply Last Post Nov 26, 2011, 2:29 a.m. EST
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Hello Mark Suchomel

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Muhammad Mohsin Rehman

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Posted: 1 decade ago Nov 26, 2011, 2:29 a.m. EST
Hi Mark,

Have you solved the problem as I am also facing a similar kind of problem in version 04a?

Thanks.
Hi Mark, Have you solved the problem as I am also facing a similar kind of problem in version 04a? Thanks.

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