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Convergence criteria of the segregated solver are met but not all conditions for group Heat transfer are fulfilled.

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Hi,

I have constantly encounter a message like this:

Convergence criteria of the segregated solver are met but not all conditions for group Heat transfer are fulfilled.

Convergence criteria of the segregated solver are met but not all conditions for group mass fraction are fulfilled.

I have coupled electric, transport of species, momentum and heat transfer in my model.

How to set the solver to let Heat transfer and Mass transfer continue to compute untill other physics converge?

Can anyone give me some advice? Thank you very much.

Best regards,

Xiaoqiang Zhang


1 Reply Last Post 22.04.2020, 06:18 GMT-4

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Posted: 5 years ago 22.04.2020, 06:18 GMT-4
Updated: 5 years ago 23.04.2020, 04:12 GMT-4

This is the log: After report this message, it will report error message. <---- Compile Equations: Stationary in Study 5/Solution 7 (sol7) ---------------
Started at Apr 22, 2020 11:53:52 AM.
Running on AMD64 Family 23 Model 113 Stepping 0, AuthenticAMD.
Using 1 socket with 12 cores in total on BRAVEHEART.
Available memory: 65.47 GB.
Number of vertex elements: 872
Number of edge elements: 8024
Number of boundary elements: 86909
Number of elements: 283592
Minimum element quality: 0.05497
Geometry shape order: Linear serendipity
Time: 16 s.
Physical memory: 21.77 GB
Virtual memory: 24.92 GB
Ended at Apr 22, 2020 11:54:09 AM.
----- Compile Equations: Stationary in Study 5/Solution 7 (sol7) -------------->
<---- Dependent Variables 1 in Study 5/Solution 7 (sol7) -----------------------
Started at Apr 22, 2020 11:54:09 AM.
Initial values of variables solved for: Solution 2 (sol2).
Solution time: 12 s.
Physical memory: 21.99 GB
Virtual memory: 23.77 GB
Ended at Apr 22, 2020 11:54:21 AM.
----- Dependent Variables 1 in Study 5/Solution 7 (sol7) ---------------------->
<---- Stationary Solver 1 in Study 5/Solution 7 (sol7) -------------------------
Started at Apr 22, 2020 11:54:21 AM.
Segregated solver
Number of degrees of freedom solved for: 4055345 (plus 592578 internal DOFs).
Segregated solver iteration 1.
Current distribution variables
Symmetric matrices found.
Scales for dependent variables:
Electrolyte potential (comp1.phil): 1.2e+02
Electric potential (comp1.phis): 0.86
Orthonormal null-space function used.
Iter SolEst Damping Stepsize #Res #Jac #Sol LinErr LinRes
1 0.0017 1.0000000 0.0017 2 1 1 1.2e-13 1.9e-16
Velocity u, Pressure p
Nonsymmetric matrix found.
Scales for dependent variables:
Pressure (comp1.p): 1e+05
Velocity field (spatial frame) (comp1.u): 1.1e+03
Orthonormal null-space function used.
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.69 0.5000000 0.69 2 1 1 12 0.00047 1.6e-06
Heat transfer
Nonsymmetric matrix found.
Scales for dependent variables:
Temperature (comp1.T): 1e+03
Orthonormal null-space function used.
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.013 0.8000000 0.013 2 1 1 47 0.00094 0.00098
Mass fractions
Nonsymmetric matrix found.
Scales for dependent variables:
Mass fraction (comp1.wCH4): 0.097
Mass fraction (comp1.wCO): 0.099
Mass fraction (comp1.wCO2): 0.088
Mass fraction (comp1.wH2): 0.027
Orthonormal null-space function used.
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 1 0.5000000 1 2 1 1 4 0.0001 8.7e-06
Mass fractions (2)
Nonsymmetric matrix found.
Scales for dependent variables:
Mass fraction (comp1.wO2): 1.2
Orthonormal null-space function used.
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.00012 0.5000000 0.00012 2 1 1 100 0.25 1
2 0.0018 0.5000000 0.0018 3 2 2 200 0.31 1
3 0.00098 0.5000000 0.00098 4 3 3 300 0.46 1
4 0.00073 0.5000000 0.00073 5 4 4 400 0.77 1
5 0.0005 0.5000000 0.0005 6 5 5 500 1.3 1
Solution error estimates for segregated groups
0.0017, 0.35, 0.011, 0.5, 0.002
Residual error estimates for segregated groups
6.8e+04, 2e+03, 6.2e+03, 4.9e+04, 3e+03
Segregated solver iteration 2.
Current distribution variables
Scales for dependent variables:
Electrolyte potential (comp1.phil): 0.16
Electric potential (comp1.phis): 0.38
Iter SolEst Damping Stepsize #Res #Jac #Sol LinErr LinRes
1 0.1 1.0000000 0.1 4 2 2 1.3e-12 5.1e-14
Velocity u, Pressure p
Scales for dependent variables:
Pressure (comp1.p): 1e+05
Velocity field (spatial frame) (comp1.u): 0.34
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.57 0.5000000 0.57 4 2 2 21 0.00084 3.1e-06
Heat transfer
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.01 0.8000000 0.01 4 2 2 85 0.00097 0.00042
Mass fractions
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.42 0.5000000 0.42 4 2 2 8 0.00012 9.6e-06
Mass fractions (2)
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 3.3e-05 0.5000000 3.3e-05 8 6 6 600 0.18 1
2 0.00025 0.5000000 0.00025 9 7 7 700 0.3 1
3 0.00021 0.5000000 0.00021 10 8 8 800 0.55 1
4 0.00031 0.5000000 0.00031 11 9 9 900 0.98 1
5 0.00022 0.5000000 0.00022 12 10 10 1000 1.8 1
Solution error estimates for segregated groups
0.1, 0.29, 0.0082, 0.21, 0.0005 Residual error estimates for segregated groups
3.5e+03, 1.2e+03, 2.8e+03, 5e+04, 3e+03
Convergence criteria of the segregated solver are met but not all conditions for group Mass fractions (2) are fulfilled.
Segregated solver iteration 3.
Current distribution variables
Iter SolEst Damping Stepsize #Res #Jac #Sol LinErr LinRes
1 0.084 1.0000000 0.084 6 3 3 1.3e-12 4.8e-14
Velocity u, Pressure p
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.75 0.5000000 0.75 6 3 3 31 0.00084 5.2e-06
Heat transfer
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.0096 0.8000000 0.0096 6 3 3 124 0.0008 0.00093
Mass fractions
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.29 0.5000000 0.29 6 3 3 12 0.00014 1e-05
Mass fractions (2)
Iter SolEst Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes

This is the log: After report this message, it will report error message.

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