"The computation failed" when I use Polyflow to simulate filling process of chemical reaction flow

I am using Polyflow to simulate the mould filling process of a chemical reaction flow, but the computation failed. I have attached the listing File, can any one help? many thanks.

 

 

Comments

  • uxsarahuxsarah Member
    edited November 2018

     Running vof for T within [ 0.000E+00 , 2.000E+02 ]
      with dT-ini = 1.000E-01,
           dT-min = 1.000E-02, dT-max = 2.500E-01,
      with up to 2000 successful steps,
     
     
     
      ===> Starting VOF
             at T-ini = 0.000E+00
      =================================
     
     
     
     
    **************************************************************************
          Initial volume     =  1.4103619E-04 / 4.1392274E-02
    **************************************************************************

     Preprocessors  

     Convergence assumed : Rel. var. LT  1.00000E-04

     F.E.M. Task    

     Global divergence has occured. Diverg =  0.2000000E+04
     
     
    **************************************************************************
        VOF Step #1                                 |   Progress bar(s)  |
          Time               =  0.0000000E+00       |>                   |
          Volume of fluid    =  1.4103619E-04       |>                   |
          Volume filled (%)  =  3.4073070E-01       |>                   |
          Step status : KO
              Solver divergence occured.
             New time step      =  5.0000000E-02
    **************************************************************************

     Preprocessors  

     Convergence assumed : Rel. var. LT  1.00000E-04

     F.E.M. Task    


    Divergence detected for field Carbondioxide: iterations cancelled by Expert System

    Divergence detected for field Urethane: iterations cancelled by Expert System
     Global divergence has occured. Diverg =  0.2000000E+04
     
     
    **************************************************************************
        VOF Step #1                                 |   Progress bar(s)  |
          Time               =  0.0000000E+00       |>                   |
          Volume of fluid    =  1.4103619E-04       |>                   |
          Volume filled (%)  =  3.4073070E-01       |>                   |
          Step status : KO
              Solver divergence occured.
             New time step      =  2.5000000E-02
    **************************************************************************

     Preprocessors  

     Convergence assumed : Rel. var. LT  1.00000E-04

     F.E.M. Task    

               *** WARNING *** from [fpow]
              Negative local temperature for power law. Stop.
               *** WARNING *** from [mat162]
              Evaluation of the reaction rate has failed. Stop.
               *** WARNING *** from [MATRIX]
              Information about the above trouble...
              for problem Reaction rate 2D
              on domain: SURFACE_BODY.
                near location : ( 0.23946E+00 ,  0.92221E-01 )
             
             
     Global divergence has occured. Diverg =  0.2000000E+04
     
     
    **************************************************************************
        VOF Step #1                                 |   Progress bar(s)  |
          Time               =  0.0000000E+00       |>                   |
          Volume of fluid    =  1.4103619E-04       |>                   |
          Volume filled (%)  =  3.4073070E-01       |>                   |
          Step status : KO
              Solver divergence occured.
             New time step      =  1.2500000E-02
    **************************************************************************

     Preprocessors  

     Convergence assumed : Rel. var. LT  1.00000E-04

     F.E.M. Task    


    Divergence detected for field Urea: iterations cancelled by Expert System
     Global divergence has occured. Diverg =  0.2000000E+04
     
     
    **************************************************************************
        VOF Step #1                                 |   Progress bar(s)  |
          Time               =  0.0000000E+00       |>                   |
          Volume of fluid    =  1.4103619E-04       |>                   |
          Volume filled (%)  =  3.4073070E-01       |>                   |
          Step status : KO
              Solver divergence occured.
             New time step      =  6.2500000E-03
    **************************************************************************

     Preprocessors  

     Convergence assumed : Rel. var. LT  1.00000E-04

     F.E.M. Task    

     Global divergence has occured. Diverg =  0.2000000E+04
     
     
    **************************************************************************
        VOF Step #1                                 |   Progress bar(s)  |
          Time               =  0.0000000E+00       |>                   |
          Volume of fluid    =  1.4103619E-04       |>                   |
          Volume filled (%)  =  3.4073070E-01       |>                   |
          Step status : KO
              Solver divergence occured.
             New time step      =  3.1250000E-03
    **************************************************************************


         *******************************
         *  Summary of the simulation  *
         *******************************

            The computation failed.


         *****************************
         *  Expert tool diagnostics  *
         *****************************

         Computation can not start, time step becomes too small at the first
         step.
         Maybe there is a problem is your set up. Please, review it.


         *****************************
         *  Expert tool diagnostics  *
         *****************************

         Out of convergence disk


         *****************************
         *  Expert tool diagnostics  *
         *****************************

         The problem F.E.M. Task     has not converged.


         *****************************
         *  Expert tool suggestions  *
         *****************************

         A serious internal error has occured (in printEndOfVof).
         Please, contact Ansys Polyflow support, and send us, if possible the
         mesh, data and listing files.
         We apologize for the inconvenience.

  • uxsarahuxsarah Member
    edited November 2018

    Is there anything wrong with my folling settings?

    VOF iterative parameters:

    Initial time value =0

    Upper time limit= 2.000E2

    Initial value of the time step= 1.000E-1

    Min admissible value of the time-step = 1.000E-2

    Max admissible value of the time-step = 2.500E-01

    Accuracy of VOF scheme =2.500E-01

    Max number of successful steps =2000

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    <w:LsdException Locked="false" Priority="72" Name="C

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