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Old   September 11, 2019, 14:44
Default Can I achieve better convergence?
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Dear All,
I am doing a simulation of axial turbine in CFX for my master thesis. Previously I had interface imbalance issue and Mr. Glenn Horrocks revealed to me poor convergence. Just when I overcome interface imbalance issue I started poor convergence investigation. After reading some guides and best practices presentations I decided to check what I possibly can.


1. Mesh. I am afraid I canít change the mesh. It is a tet-dominant mesh with inflation layer (y+=1) on every wall. Geometry was provided by 3rd party company and it was very hard to divide it into parts good for structural meshing. In the end after many attempts I gave up and decide to use tet-dominant mesh. Please, see attachment.

2. I tried upwind and high resolution schemes.

3. I tried relaxation factor 0.2

4. I tried to use physical timescale set to 1e-7. It should be suitable for my case.

5. Since I am interested in flow separation in tip-shroud clearance and influence of labyrinth seal, I tried only SST turbulence model and I would not like to switch to lower order turbulence models.

I think that it is not a convergence issue but the problem is not a steady state, thus there is no way to achieve convergence. In that case running a transient simulation would be a solution. Unfortunately the mesh is 8mln elements, 7 simulations needs to be performed and I cannot spend so much time for this project.
So my question is if I can improve convergence for that case or due to transient behaviour nothing can be done?

Is there anything like non orthogonal correction in CFX?


Best regards,
Oskar
Attached Images
File Type: jpg RMS.jpg (151.8 KB, 33 views)
File Type: png MAX.png (78.9 KB, 21 views)
File Type: png H.png (28.2 KB, 19 views)
File Type: png Turb.png (67.3 KB, 19 views)
File Type: png Mesh.png (73.6 KB, 26 views)
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Old   September 11, 2019, 15:27
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You have not mentioned which timescale was used to obtain the Upwind/High Resolution simulations
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Old   September 11, 2019, 16:13
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Thank You for Your answer.

Iterations 1-303 was done with auto timescale, conservative, timescale factor 1.0. CFX default.
Please, find the attachment for the settings.


Best regards,
Oskar
Attached Images
File Type: png 120.png (12.8 KB, 9 views)
File Type: png 303.png (21.7 KB, 9 views)
File Type: png 404.png (11.8 KB, 10 views)
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Old   September 11, 2019, 16:16
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Based on your previous convergence plots, I would try the following

One simulation using Timescale Factor = 2, and another with Timescale Factor = 0.5

to understand the sensitivity of your problem. Those results will guide in the proper direction.
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Old   September 11, 2019, 17:46
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Thank You for Your reply.
I need about 2 days for both simulations so please, expect delayed answer.


Best regards,
Oskar
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Old   September 11, 2019, 19:59
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Your question is an FAQ: https://www.cfd-online.com/Wiki/Ansy...gence_criteria

The FAQ covers Opaque's suggestion - I would recommend using "edit run in progress" rather than separate runs for this test so you can see the results straight away. If it is not working you then try something else, if it is working then you give it more of that.

But given you are modelling tip clearance separations and labyrinth seals it appears highly likely that your flow has transient features in these areas. In that case the only reliable way forwards will be transient simulations. Yes, this will take longer; but one of the biggest customers for supercomputers is CFD and now you can see why. CFD on desktops is always going to be very limiting.
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Old   September 13, 2019, 10:24
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Dear Glenn,
Thank You for Your reply. I know that there is a FAQ related to convergence issues. I went through it. But without adequat experience not everything is obvious. For example it was hard to tell if there are regions in my domain that can not be converged in steady state solution. My question was rather if I can do something more that that, with respect to time and performance constrains that I have.



Dear Opaque.


One simulation was ended a little bit too early and k from turbulence model did not stabilized. I know that running a few more iterations would not affects other variables.



I am attaching results of simulation with Timescale Factor 0.5.
Attached Images
File Type: jpg rms0.5.jpg (138.9 KB, 9 views)
File Type: png max0.5.png (78.1 KB, 6 views)
File Type: png H0.5.png (30.3 KB, 6 views)
File Type: jpg ko0.5.jpg (58.9 KB, 6 views)
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Old   September 13, 2019, 10:28
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Due to limitations I had to put results for Timescale Factor 2 in separate reply.


Dear Opaque,
What is Your opinion? Is there something I can do to get better convergence? Or playing with those settings just help me reach the same results with less iterations?



Best regards,
Oskar
Attached Images
File Type: png RMS2.png (45.8 KB, 11 views)
File Type: png max2.png (66.1 KB, 11 views)
File Type: png H2.png (19.3 KB, 8 views)
File Type: jpg ko2.jpg (67.0 KB, 7 views)
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Old   September 15, 2019, 20:05
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You need to compare the convergence of this run to the one with a different time scale factor to see if it changed things.

You also need to determine whether the convergence you are currently getting is adequate. Do a sensitivity study on convergence residual and see if you need to go tighter.

The FAQ really does list the procedure to follow, that is why we wrote it. If you need to converge tighter and the changes you are making are not getting there then you need to go transient. It is step 5 in the FAQ.
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Old   September 19, 2019, 10:17
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Thank You for Your reply.


As I can see factor scale does not influence on residuals.

I assume there is no way for better convergence in steady state.


Thank You again.
Best regards,
Oskar
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Old   September 19, 2019, 14:12
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Have you written the equation residuals to results file?

Have you located where the maximum residual for a given equation in the post-processor?

What does the flow pattern look like around there?

What does the mesh quality look like around there?

How much imbalance each equation has?

etc?
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Old   September 19, 2019, 16:35
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Thank You for Your reply.

Yes, I have written the equation residuals to results file during.

Yes, I have located where the maximum residual for a given equation in the post-processor. They are located near labyrinth seal.

The flow pattern around labyrinth seal looks normal to me. This is something I was expecting.

The mesh around labyrinth seal is provided. I think high skewness of inflation layer near edges might cause high residuals here.

Summaries for recent run:
Code:
 ======================================================================
              Termination and Interrupt Condition Summary
 ======================================================================
    
 CFD Solver: Run duration reached
   (Maximum number of outer iterations)

 ======================================================================
              Boundary Flow and Total Source Term Summary
 ======================================================================

 +--------------------------------------------------------------------+
 |                              U-Mom-R1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 Blade                               -1.1747E+01
 Boundary         : R1 Default                             -4.4099E-01
 Boundary         : R1 Hub                                 -4.1671E+00
 Boundary         : R1 Outlet                              -1.7331E-01
 Boundary         : R1 Shroud                               7.0479E+00
 Boundary         : R1 to S1 Side 1                         3.9966E-04
 Domain Src (Neg) : R1                                     -5.2646E-01
 Domain Src (Pos) : R1                                      2.2624E-01
 Domain Interface : R1 to R1 Periodic 1 (Side 1)           -2.2981E+01
 Domain Interface : R1 to R1 Periodic 1 (Side 2)            2.1245E+01
 Domain Interface : R1 to S1 (Side 1)                       1.1517E+01
                                                           -----------
 Domain Imbalance :                                         9.2285E-06

 +--------------------------------------------------------------------+
 |                              V-Mom-R1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 Blade                               -9.4746E+00
 Boundary         : R1 Default                             -1.1137E-02
 Boundary         : R1 Hub                                  8.8770E-01
 Boundary         : R1 Outlet                              -3.4292E+01
 Boundary         : R1 Shroud                              -2.8880E-01
 Boundary         : R1 to S1 Side 1                         2.2473E-01
 Domain Interface : R1 to R1 Periodic 1 (Side 1)           -9.8782E+00
 Domain Interface : R1 to R1 Periodic 1 (Side 2)            9.8731E+00
 Domain Interface : R1 to S1 (Side 1)                       4.2959E+01
                                                           -----------
 Domain Imbalance :                                        -1.1226E-05

 +--------------------------------------------------------------------+
 |                              W-Mom-R1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 Blade                               -1.6812E-02
 Boundary         : R1 Default                              2.6771E+00
 Boundary         : R1 Hub                                  1.4675E+01
 Boundary         : R1 Outlet                               1.1334E-01
 Boundary         : R1 Shroud                              -3.3846E+01
 Boundary         : R1 to S1 Side 1                         5.2658E-05
 Domain Src (Neg) : R1                                     -1.1966E-01
 Domain Src (Pos) : R1                                      2.5554E+00
 Domain Interface : R1 to R1 Periodic 1 (Side 1)            3.0958E+00
 Domain Interface : R1 to R1 Periodic 1 (Side 2)            9.2963E+00
 Domain Interface : R1 to S1 (Side 1)                       1.5696E+00
                                                           -----------
 Domain Imbalance :                                        -2.2136E-05

 +--------------------------------------------------------------------+
 |                             P-Mass-R1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 Outlet                              -3.1468E-02
 Domain Interface : R1 to R1 Periodic 1 (Side 1)            4.0164E-03
 Domain Interface : R1 to R1 Periodic 1 (Side 2)           -4.0164E-03
 Domain Interface : R1 to S1 (Side 1)                       3.1468E-02
                                                           -----------
 Domain Imbalance :                                        -4.5130E-08

 +--------------------------------------------------------------------+
 |                              U-Mom-S1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 to S1 Side 2                        -4.5017E-06
 Boundary         : S1 Blade                                8.3849E+00
 Boundary         : S1 Hub                                 -2.1923E+01
 Boundary         : S1 Inlet                               -1.1298E-05
 Boundary         : S1 Shroud                               3.6273E+01
 Domain Interface : R1 to S1 (Side 2)                      -8.8834E+00
 Domain Interface : S1 to S1 Periodic 1 (Side 1)            7.3223E+01
 Domain Interface : S1 to S1 Periodic 1 (Side 2)           -8.7075E+01
                                                           -----------
 Domain Imbalance :                                         4.3321E-05

 +--------------------------------------------------------------------+
 |                              V-Mom-S1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 to S1 Side 2                        -3.4227E-03
 Boundary         : S1 Blade                               -8.9200E+00
 Boundary         : S1 Hub                                 -1.8115E+00
 Boundary         : S1 Inlet                                4.6208E+01
 Boundary         : S1 Shroud                              -2.9287E+00
 Domain Interface : R1 to S1 (Side 2)                      -3.2798E+01
 Domain Interface : S1 to S1 Periodic 1 (Side 1)           -2.7364E+01
 Domain Interface : S1 to S1 Periodic 1 (Side 2)            2.7617E+01
                                                           -----------
 Domain Imbalance :                                        -8.5211E-06

 +--------------------------------------------------------------------+
 |                              W-Mom-S1                              |
 +--------------------------------------------------------------------+
 Boundary         : R1 to S1 Side 2                        -1.1492E-06
 Boundary         : S1 Blade                                3.5774E+00
 Boundary         : S1 Hub                                  4.6621E+01
 Boundary         : S1 Inlet                                2.3413E-05
 Boundary         : S1 Shroud                              -8.3402E+01
 Domain Interface : R1 to S1 (Side 2)                      -8.3869E-01
 Domain Interface : S1 to S1 Periodic 1 (Side 1)            4.9570E+01
 Domain Interface : S1 to S1 Periodic 1 (Side 2)           -1.5528E+01
                                                           -----------
 Domain Imbalance :                                         8.2900E-06

 +--------------------------------------------------------------------+
 |                             P-Mass-S1                              |
 +--------------------------------------------------------------------+
 Boundary         : S1 Inlet                                2.4126E-02
 Domain Interface : R1 to S1 (Side 2)                      -2.4126E-02
 Domain Interface : S1 to S1 Periodic 1 (Side 1)           -8.0795E-04
 Domain Interface : S1 to S1 Periodic 1 (Side 2)            8.0795E-04
                                                           -----------
 Domain Imbalance :                                         4.4941E-08

 +--------------------------------------------------------------------+
 |                            H-Energy-R1                             |
 +--------------------------------------------------------------------+
 Boundary         : R1 Outlet                               5.2984E+03
 Bnd Src/Visc Work: R1 Outlet                              -2.7143E-03
 Bnd Src/Visc Work: R1 Shroud                               1.9268E+01
 Bnd Src/Visc Work: R1 to R1 Periodic 1 Side 1             -8.9716E-01
 Bnd Src/Visc Work: R1 to R1 Periodic 1 Side 2              1.0880E+00
 Bnd Src/Visc Work: R1 to S1 Side 1                         9.2097E-01
 Domain Src (Neg) : R1                                     -6.9401E+02
 Domain Src (Pos) : R1                                      6.9401E+02
 Domain Interface : R1 to R1 Periodic 1 (Side 1)           -6.9583E+02
 Domain Interface : R1 to R1 Periodic 1 (Side 2)            6.9581E+02
 Domain Interface : R1 to S1 (Side 1)                      -5.3188E+03
                                                           -----------
 Domain Imbalance :                                         1.4477E-02

 +--------------------------------------------------------------------+
 |                            H-Energy-S1                             |
 +--------------------------------------------------------------------+
 Bnd Src/Visc Work: R1 to S1 Side 2                         3.3822E+00
 Boundary         : S1 Inlet                               -8.0098E+02
 Bnd Src/Visc Work: S1 Inlet                                7.5531E-05
 Bnd Src/Visc Work: S1 to S1 Periodic 1 Side 1             -6.8310E-01
 Bnd Src/Visc Work: S1 to S1 Periodic 1 Side 2              6.9531E-01
 Domain Src (Neg) : S1                                     -4.7419E+02
 Domain Src (Pos) : S1                                      4.7419E+02
 Domain Interface : R1 to S1 (Side 2)                       7.9759E+02
 Domain Interface : S1 to S1 Periodic 1 (Side 1)            2.6839E+01
 Domain Interface : S1 to S1 Periodic 1 (Side 2)           -2.6839E+01
                                                           -----------
 Domain Imbalance :                                        -1.1489E-03


 +--------------------------------------------------------------------+
 |                     Normalised Imbalance Summary                   |
 +--------------------------------------------------------------------+
 |       Equation       |      Maximum Flow     |     Imbalance (%)   |
 +--------------------------------------------------------------------+
 | U-Mom-R1             |       8.7075E+01      |        0.0000       |
 | V-Mom-R1             |       8.7075E+01      |       -0.0000       |
 | W-Mom-R1             |       8.7075E+01      |       -0.0000       |
 | P-Mass-R1            |       3.1468E-02      |       -0.0001       |
 | U-Mom-S1             |       8.7075E+01      |        0.0000       |
 | V-Mom-S1             |       8.7075E+01      |       -0.0000       |
 | W-Mom-S1             |       8.7075E+01      |        0.0000       |
 | P-Mass-S1            |       3.1468E-02      |        0.0001       |
 +----------------------+-----------------------+---------------------+
 | H-Energy-R1          |       5.3188E+03      |        0.0003       |
 | H-Energy-S1          |       5.3188E+03      |       -0.0000       |
 +----------------------+-----------------------+---------------------+
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Old   September 19, 2019, 16:36
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Code:
======================================================================
                     Wall Force and Moment Summary
 ======================================================================
                                                                          
 Notes:
 1. Pressure integrals exclude the reference pressure.  To include
    it, set the expert parameter 'include pref in forces = t'.
 2. These quantities are evaluated in a reference frame fixed to
    the initial domain orientation and are not rotated if the orientation
    changes (e.g. transient run or specified rotational offset).


 +--------------------------------------------------------------------+
 |                      Pressure Force On Walls                       |
 +--------------------------------------------------------------------+
                                    X-Comp.      Y-Comp.      Z-Comp.

 Domain Group: R1

 R1 Blade                         1.1824E+01   9.3102E+00   1.6830E-02
 R1 Default                       4.3902E-01   1.0905E-05  -2.6773E+00
 R1 Hub                           4.2028E+00  -9.1163E-01  -1.4664E+01
 R1 Shroud                       -7.0909E+00   2.4660E-01   3.3842E+01
 R1 to S1 Side 1                  1.0555E-12  -2.2473E-01  -7.5739E-12
 R1 to S1 Side 2                  3.6939E-15   3.4227E-03  -1.1839E-14
 S1 Blade                        -8.4555E+00   8.8352E+00  -3.5742E+00
 S1 Hub                           2.1895E+01   1.7742E+00  -4.6631E+01
 S1 Shroud                       -3.6319E+01   2.8867E+00   8.3392E+01
                                  -----------  -----------  -----------
 Domain Group Totals :           -1.3505E+01   2.1920E+01   4.9705E+01


 +--------------------------------------------------------------------+
 |                       Viscous Force On Walls                       |
 +--------------------------------------------------------------------+
                                    X-Comp.      Y-Comp.      Z-Comp.

 Domain Group: R1

 R1 Blade                        -7.6953E-02   1.6442E-01  -1.8255E-05
 R1 Default                       1.9761E-03   1.1126E-02   1.9600E-04
 R1 Hub                          -3.5698E-02   2.3930E-02  -1.1260E-02
 R1 Shroud                        4.2986E-02   4.2202E-02   4.3145E-03
 R1 to S1 Side 1                 -3.9966E-04   7.8473E-14  -5.2658E-05
 R1 to S1 Side 2                  4.5017E-06   8.2945E-10   1.1492E-06
 S1 Blade                         7.0595E-02   8.4875E-02  -3.2013E-03
 S1 Hub                           2.8384E-02   3.7293E-02   9.2984E-03
 S1 Shroud                        4.6013E-02   4.1943E-02   1.0320E-02
                                  -----------  -----------  -----------
 Domain Group Totals :            7.6907E-02   4.0579E-01   9.5976E-03


 +--------------------------------------------------------------------+
 |                      Pressure Moment On Walls                      |
 +--------------------------------------------------------------------+
                                    X-Comp.      Y-Comp.      Z-Comp.

 Domain Group: R1

 R1 Blade                        -2.6641E-01   3.3460E-01  -3.0467E-01
 R1 Default                      -5.7810E-02   7.9054E-07  -9.7046E-03
 R1 Hub                          -3.2469E-01   8.6648E-06  -1.0426E-01
 R1 Shroud                        7.6020E-01  -2.1980E-06   1.6896E-01
 R1 to S1 Side 1                  7.7621E-03   1.0474E-15   1.0150E-03
 R1 to S1 Side 2                 -7.4291E-05   3.2282E-18  -2.0426E-05
 S1 Blade                        -2.6532E-01  -2.6557E-01  -1.2862E-02
 S1 Hub                          -5.4947E-02  -4.1879E-06   9.4704E-03
 S1 Shroud                        2.2683E-03   3.5611E-06  -7.9478E-02
                                  -----------  -----------  -----------
 Domain Group Totals :           -1.9902E-01   6.9041E-02  -3.3155E-01


 +--------------------------------------------------------------------+
 |                       Viscous Moment On Walls                      |
 +--------------------------------------------------------------------+
                                    X-Comp.      Y-Comp.      Z-Comp.

 Domain Group: R1

 R1 Blade                        -4.6086E-03  -2.2839E-03   1.0277E-03
 R1 Default                      -3.7564E-04   6.9935E-05  -1.0758E-04
 R1 Hub                          -7.8260E-04  -8.4134E-04   7.1535E-04
 R1 Shroud                       -1.3628E-03   1.5333E-03  -1.1327E-03
 R1 to S1 Side 1                 -9.0045E-07  -1.4400E-05   6.8342E-06
 R1 to S1 Side 2                  1.9633E-08   1.0454E-07  -7.6984E-08
 S1 Blade                        -2.2688E-03   1.9441E-03  -1.7304E-03
 S1 Hub                          -6.6213E-04   6.8768E-04  -6.5705E-04
 S1 Shroud                       -1.2264E-03   1.6723E-03  -1.1178E-03
                                  -----------  -----------  -----------
 Domain Group Totals :           -1.1288E-02   2.7678E-03  -2.9957E-03


 +--------------------------------------------------------------------+
 |                   Locations of Maximum Residuals                   |
 +--------------------------------------------------------------------+
 |       Equation       |      Domain Name      |     Node Number     |
 +--------------------------------------------------------------------+
 | U-Mom                | R1                    |        3130374      |
 | V-Mom                | R1                    |        1710546      |
 | W-Mom                | R1                    |        3391343      |
 | P-Mass               | R1                    |        3383351      |
 +----------------------+-----------------------+---------------------+
 | H-Energy             | R1                    |        3157650      |
 +----------------------+-----------------------+---------------------+
 | K-TurbKE             | R1                    |        3304705      |
 | O-TurbFreq           | R1                    |        4098281      |
 +----------------------+-----------------------+---------------------+

 ======================================================================
 |                     False Transient Information                    |
 +--------------------------------------------------------------------+
 |       Equation       |         Type          | Elapsed Pseudo-Time |
 +--------------------------------------------------------------------+
 | U-Mom-R1             | Auto Timescale        |     5.06113E-03     |
 | V-Mom-R1             | Auto Timescale        |     5.06113E-03     |
 | W-Mom-R1             | Auto Timescale        |     5.06113E-03     |
 | P-Mass-R1            | Auto Timescale        |     5.06113E-03     |
 | U-Mom-S1             | Auto Timescale        |     5.06113E-03     |
 | V-Mom-S1             | Auto Timescale        |     5.06113E-03     |
 | W-Mom-S1             | Auto Timescale        |     5.06113E-03     |
 | P-Mass-S1            | Auto Timescale        |     5.06113E-03     |
 +----------------------+-----------------------+---------------------+
 | H-Energy-R1          | Auto Timescale        |     5.06113E-03     |
 | H-Energy-S1          | Auto Timescale        |     5.06113E-03     |
 +----------------------+-----------------------+---------------------+
 | K-TurbKE-R1          | Auto Timescale        |     5.06113E-03     |
 | O-TurbFreq-R1        | Auto Timescale        |     5.06113E-03     |
 | K-TurbKE-S1          | Auto Timescale        |     5.06113E-03     |
 | O-TurbFreq-S1        | Auto Timescale        |     5.06113E-03     |
 +----------------------+-----------------------+---------------------+

 +--------------------------------------------------------------------+
 |                     Average Scale Information                      |
 +--------------------------------------------------------------------+

 Domain Name : R1
     Global Length                                         = 1.3492E-02
     Minimum Extent                                        = 1.2900E-02
     Maximum Extent                                        = 2.4833E-02
     Density                                               = 5.3313E-01
     Dynamic Viscosity                                     = 3.9868E-05
     Velocity                                              = 3.3704E+02
     Advection Time                                        = 4.0030E-05
     Reynolds Number                                       = 6.0808E+04
     Speed of Sound                                        = 5.9351E+02
     Mach Number                                           = 5.6788E-01
     Thermal Conductivity                                  = 6.9439E-02
     Specific Heat Capacity at Constant Pressure           = 1.1701E+03
     Specific Heat Capacity at Constant Volume             = 8.8048E+02
     Specific Heat Ratio                                   = 1.3289E+00
     Prandtl Number                                        = 6.7181E-01
     Temperature Range                                     = 4.6606E+02

 Domain Name : S1
     Global Length                                         = 1.6438E-02
     Minimum Extent                                        = 1.8582E-02
     Maximum Extent                                        = 2.9400E-02
     Density                                               = 7.8387E-01
     Dynamic Viscosity                                     = 4.1088E-05
     Velocity                                              = 2.6334E+02
     Advection Time                                        = 6.2423E-05
     Reynolds Number                                       = 8.2586E+04
     Speed of Sound                                        = 6.0745E+02
     Mach Number                                           = 4.3352E-01
     Thermal Conductivity                                  = 6.9439E-02
     Specific Heat Capacity at Constant Pressure           = 1.1810E+03
     Specific Heat Capacity at Constant Volume             = 8.9140E+02
     Specific Heat Ratio                                   = 1.3249E+00
     Prandtl Number                                        = 6.9883E-01
     Temperature Range                                     = 1.5059E+02

 +--------------------------------------------------------------------+
 |                     Variable Range Information                     |
 +--------------------------------------------------------------------+

 Domain Name : R1
 +--------------------------------------------------------------------+
 |      Variable Name                         |    min    |    max    |
 +--------------------------------------------------------------------+
 | Density                                    |  8.34E-02 |  7.57E-01 |
 | Specific Heat Capacity at Constant Pressure|  1.10E+03 |  1.21E+03 |
 | Dynamic Viscosity                          |  3.23E-05 |  4.54E-05 |
 | Thermal Conductivity                       |  6.94E-02 |  6.94E-02 |
 | Isothermal Compressibility                 |  4.84E-06 |  4.93E-05 |
 | Static Entropy                             |  8.02E+03 |  8.56E+03 |
 | Velocity u                                 | -7.25E+02 |  4.56E+02 |
 | Velocity v                                 | -3.28E+02 |  6.94E+02 |
 | Velocity w                                 | -5.86E+02 |  3.29E+02 |
 | Pressure                                   |  2.03E+04 |  2.07E+05 |
 | Turbulence Kinetic Energy                  |  1.50E-03 |  2.25E+04 |
 | Turbulence Eddy Frequency                  |  1.73E+05 |  2.13E+10 |
 | Eddy Viscosity                             |  1.67E-13 |  4.12E-03 |
 | Temperature                                |  6.64E+02 |  1.13E+03 |
 | Static Enthalpy                            | -4.10E+05 |  1.34E+05 |
 | Total Enthalpy                             | -2.17E+05 |  2.16E+05 |
 | Wall Scale                                 | -1.60E-09 |  1.16E-05 |
 | Wall Distance                              |  0.00E+00 |  4.67E-03 |
 +--------------------------------------------------------------------+

 Domain Name : S1
 +--------------------------------------------------------------------+
 |      Variable Name                         |    min    |    max    |
 +--------------------------------------------------------------------+
 | Density                                    |  3.97E-01 |  9.09E-01 |
 | Specific Heat Capacity at Constant Pressure|  1.15E+03 |  1.19E+03 |
 | Dynamic Viscosity                          |  3.78E-05 |  4.19E-05 |
 | Thermal Conductivity                       |  6.94E-02 |  6.94E-02 |
 | Isothermal Compressibility                 |  3.83E-06 |  9.01E-06 |
 | Static Entropy                             |  8.02E+03 |  8.23E+03 |
 | Velocity u                                 | -2.97E+02 |  4.66E+02 |
 | Velocity v                                 | -1.37E+02 |  5.85E+02 |
 | Velocity w                                 | -1.82E+02 |  2.08E+02 |
 | Pressure                                   |  1.11E+05 |  2.61E+05 |
 | Turbulence Kinetic Energy                  |  3.21E-03 |  8.23E+03 |
 | Turbulence Eddy Frequency                  |  7.94E+04 |  5.02E+09 |
 | Eddy Viscosity                             |  2.47E-12 |  1.62E-03 |
 | Temperature                                |  8.43E+02 |  9.94E+02 |
 | Static Enthalpy                            | -2.09E+05 | -3.26E+04 |
 | Total Enthalpy                             | -6.78E+04 | -2.98E+04 |
 | Wall Scale                                 | -9.47E-11 |  2.45E-05 |
 | Wall Distance                              |  0.00E+00 |  6.98E-03 |
 +--------------------------------------------------------------------+
It looks like energy equation is worst converged.

Your further assistance would be highly appreciated.

Best regards,
Oskar
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