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mixture flow error

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Hi
I'm trying to model a simple stationary mixture laminar flow, however I counter this error

Failed to find a solution.
Singular matrix.

There are 4567 void equations (empty rows in matrix) for the variable mod1.phid
at coordinates: (0.00699301,0), (0.013986,0), (0.00699301,0.00122764), (0.020979,0), (0.00699301,0.25), ...
Returned solution is not converged.

In this project we are aiming to observe the fluidize bed.
I've tried to change every bit of my material but the result was the same.
mean while I'm attaching the whole project
I will be glad if you could help me
best regards
Babak Alizadeh


3 Replies Last Post Jul 9, 2012, 11:03 p.m. EDT

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Posted: 1 decade ago Jul 9, 2012, 11:42 a.m. EDT
hi
i have the same problem
:(
is there anybody can help me to solve this problem ????
thanks
hi i have the same problem :( is there anybody can help me to solve this problem ???? thanks

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Posted: 1 decade ago Jul 9, 2012, 12:53 p.m. EDT
Hi
I solved the first problem by giving the initial condition for phid, since my project is in 2d it gives me this problem while it's converging

Failed to find a solution.
Maximum number of Newton iterations reached.
Returned solution is not converged.

what should I do?
It is emergency please help me
Best regard
Babak Alizadeh
Hi I solved the first problem by giving the initial condition for phid, since my project is in 2d it gives me this problem while it's converging Failed to find a solution. Maximum number of Newton iterations reached. Returned solution is not converged. what should I do? It is emergency please help me Best regard Babak Alizadeh

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Posted: 1 decade ago Jul 9, 2012, 11:03 p.m. EDT
hi
I have the same problem the other problem is how i can change the of determine the viscosity, while the software always using the Krieger expression to determine it. how i can use another equation to calculate the viscosity.
thanks
hi I have the same problem the other problem is how i can change the of determine the viscosity, while the software always using the Krieger expression to determine it. how i can use another equation to calculate the viscosity. thanks

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