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Nolinear solver did not converge. Out of memory during LU factorization
Posted 09.01.2013, 04:59 GMT-5 Studies & Solvers Version 4.1 1 Reply
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Hello,
I am building a model using version 4.1, in which heat transfer driven melting of paraffin. Each time I compute, is solves at first and then the following error appears:
Nonlinear solver did not converge.
Out of memory during LU factorization
Last time step did not converge.
I have tried increasing the mesh density or changing the solver PARDISO to SPOOLES or MUMPS. but I keep getting the same error after some time. It takes longer to appear.
I would really appreciate any help.
Here attach file is my model, can you read my model and tell me what's wrong with the model?
Thank you very much.
XL Wang
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I am building a model using version 4.1, in which heat transfer driven melting of paraffin. Each time I compute, is solves at first and then the following error appears:
Nonlinear solver did not converge.
Out of memory during LU factorization
Last time step did not converge.
I have tried increasing the mesh density or changing the solver PARDISO to SPOOLES or MUMPS. but I keep getting the same error after some time. It takes longer to appear.
I would really appreciate any help.
Here attach file is my model, can you read my model and tell me what's wrong with the model?
Thank you very much.
XL Wang
Reply | Reply with Quote | Send private message | Report Abuse
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1 Reply Last Post 09.01.2013, 15:33 GMT-5
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Posted:
1 decade ago
Hi
your "all 0" default initial conditions are quite far off the solution given size and velocities, not even sure you are in laminar flow regime.
I would suggest to run first a stationary solver, then a time series by using the result of the stationary case for the initial values of the time series, in this way, the fluid flow, pressure drop and overall temperatures will be in a reasonable coherent starting point.
Do not forget CFD require detailed boundary mesh related to the Reynolds number too, this is mostly very RAM requiring
--
Good luck
Ivar
your "all 0" default initial conditions are quite far off the solution given size and velocities, not even sure you are in laminar flow regime.
I would suggest to run first a stationary solver, then a time series by using the result of the stationary case for the initial values of the time series, in this way, the fluid flow, pressure drop and overall temperatures will be in a reasonable coherent starting point.
Do not forget CFD require detailed boundary mesh related to the Reynolds number too, this is mostly very RAM requiring
--
Good luck
Ivar