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Mixture Model Turbulent Flow Singular matrix for more refined mesh....help please

Posted 03.03.2011, 11:29 GMT-5 Computational Fluid Dynamics (CFD), Mesh, Parameters, Variables, & Functions Version 4.0a 0 Replies

Rui Silva
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Hi folks.

I'm trying to simulate a solid-liquid homogeneous flow to compare pressure drop with real data.

The pressure drop begins to converge to te values I have from experimentation, however, as I refine the mesh (as you can see in the file I have uploaded), I get the following error:

Segregated group X2
Singular matrix.
- Detail:
There are 1046 equations giving NaN/Inf in the matrix rows for the variable mod1.ep
at coordinates: (0.0242203,2.04102), (0.0111238,2.07098), (0.0148442,2.06887), (0.0185711,2.06674), (0.0167076,2.0678), ...
There are 59 equations giving NaN/Inf in the matrix rows for the variable mod1.k
at coordinates: (0.026115,2.07236), (0.026115,2.07735), (0.026115,2.08234), (0.026115,2.0998), (0.026115,2.1023), ...

There are 1036 degrees of freedom giving NaN/Inf in the matrix columns for the variable mod1.ep
at coordinates: (0.0242203,2.04102), (0.0111238,2.07098), (0.0148442,2.06887), (0.0185711,2.06674), (0.0167076,2.0678), ...
There are 59 degrees of freedom giving NaN/Inf in the matrix columns for the variable mod1.k
at coordinates: (0.026115,2.07236), (0.026115,2.07735), (0.026115,2.08234), (0.026115,2.0998), (0.026115,2.1023), ...

I get convergence for inferior mesh sizes.

Hope anyone can help.

Much appreciated.

Rui

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0 Replies Last Post 03.03.2011, 11:29 GMT-5
COMSOL Moderator

Hello Rui Silva

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