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Radiation in semi-transparent media with surface-to-surface model?

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Old   June 2, 2015, 11:49
Default Radiation in semi-transparent media with surface-to-surface model?
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Max
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Hi everyone,

I'd like to model the radiation through a quartz glass plate that separates two fluid domains (fluid domains are set up with surface-to-surface MC radiation model).

At the moment, all the information I have given about the glass is a transmissivity. I am doing a preliminary qualitative study, and I presume that the error I would make by neglecting the participating influence of the glass is well below the order of accuracy I am looking for right now.

The question is though: Is it possible at all to do this set-up in CFX?
I am a little lost, because choosing from the three options for a GGI between fluid domain and glass plate (Conservative Interface Flux: doesn't allow for any further specifications // Opaque: -> transimissvity=0 // Side-dependent: also only allows for 'Opaque' option on the domain-level boundary) I cannot find a possibility to specify a transimissivity.

Thanks for your help!

Best,
Max
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Old   June 2, 2015, 22:28
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If you are modeling only the fluid domains, and separated by a thin wall and you would like to model the transmission through the glass as well, the answer is NO.

If you are modeling the fluid domains separated by a solid domain, you activate radiation in the solid, setup the properties for quartz (absorption coefficient, and refractive index). Then, you must use the Conservative Interface Flux boundary condition.

As far as I understand, there is no such a thing as transmissivity for a substance. Emissivity, reflectivity, transmissivity and absorptivity are effective surface quantities, but not thermodynamic nor transport properties.

If you can take a look at a radiative heat transfer textbook (say M. Modest book, or Siegel and Howell), you can see how to compute the effective transmissivity for a semi-transparent solid based on refractive indexes, and absorption coefficient. You can use such formulas to back out the "absorption coefficient" of quartz if you know the thickness for which the transmissivity was given.


My 2 cents.
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Old   June 3, 2015, 13:01
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Alright, thank you, I set it up with an absorption coefficient which corresponds to the transmittance (I accidentally called it transmissivity in the first post, thank you for noticing) I am given.

However, the solver cannot handle my setup and breaks down in coeff. loop 1 as it enters the MC-algorithm.

I attached the CCL dscription of the three domains in question (fluid domains called 'FDS' and 'IC' and solid domain called 'Window' and their corresponding interfaces.

Maybe you are willing to look through it and see if you find something suspicious because I did several times and couldn't figure out what's wrong here:

FDS:

Code:
FLOW: Flow Analysis 1
  &replace DOMAIN: FDS
    Coord Frame = Coord 0
    Domain Type = Fluid
    Location = VOLUMENK_RPER_1_1_SOLID
    BOUNDARY: FDS_Wall_Adiabatic
      Boundary Type = WALL
      Create Other Side = Off
      Interface Boundary = Off
      Location = FDS_MANTLE_IN7,FDS_BOTTOM,FDS_MANTLE_IN6,FDS_TOP2,FDS_TOP1,FDS_MANTLE_OUT
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Adiabatic
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Diffuse Fraction = 1.
          Emissivity = 1.
          Option = Opaque
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
    END
    BOUNDARY: FDS_Wall_Isothermal
      Boundary Type = WALL
      Create Other Side = Off
      Interface Boundary = Off
      Location = Primitive 2D H,Primitive 2D K,Primitive 2D B,Primitive 2D D,Primitive 2D F
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Fixed Temperature = Treactorwall
          Option = Fixed Temperature
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Diffuse Fraction = 1.
          Emissivity = 1.
          Option = Opaque
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
    END
    BOUNDARY: FMDS_PER Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = FDS_PER1
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        TURBULENCE: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: FMDS_PER Side 2
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = FDS_PER2
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        TURBULENCE: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: GGI_FDS_WINDOW Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = FDS_MANTLE_IN8
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
    END
    DOMAIN MODELS: 
      BUOYANCY MODEL: 
        Buoyancy Reference Density = 1.2922 [kg m^-3]
        Gravity X Component = 0 [m s^-2]
        Gravity Y Component = 0 [m s^-2]
        Gravity Z Component = -9.81 [m s^-2]
        Option = Buoyant
        BUOYANCY REFERENCE LOCATION: 
          Option = Automatic
        END
      END
      DOMAIN MOTION: 
        Option = Stationary
      END
      MESH DEFORMATION: 
        Option = None
      END
      REFERENCE PRESSURE: 
        Reference Pressure = 1 [atm]
      END
    END
    FLUID DEFINITION: Fluid 1
      Material = Air Ideal Gas
      Option = Material Library
      MORPHOLOGY: 
        Option = Continuous Fluid
      END
    END
    FLUID MODELS: 
      COMBUSTION MODEL: 
        Option = None
      END
      HEAT TRANSFER MODEL: 
        Include Viscous Dissipation Term = On
        Option = Thermal Energy
      END
      THERMAL RADIATION MODEL: 
        Number of Histories = 10000
        Option = Monte Carlo
        Radiation Transfer Mode = Surface to Surface
        SCATTERING MODEL: 
          Option = None
        END
        SPECTRAL MODEL: 
          Option = Gray
        END
      END
      TURBULENCE MODEL: 
        Option = k epsilon
        BUOYANCY TURBULENCE: 
          Option = None
        END
      END
      TURBULENT HEAT TRANSFER: 
        TURBULENT FLUX CLOSURE: 
          Option = Eddy Diffusivity
          Turbulent Prandtl Number = 7.0462E-01
        END
      END
      TURBULENT WALL FUNCTIONS: 
        Option = Scalable
      END
    END
    INITIALISATION: 
      Option = Automatic
      INITIAL CONDITIONS: 
        Velocity Type = Cartesian
        CARTESIAN VELOCITY COMPONENTS: 
          Option = Automatic
        END
        RADIATION INTENSITY: 
          Option = Automatic
        END
        STATIC PRESSURE: 
          Option = Automatic
        END
        TEMPERATURE: 
          Option = Automatic
        END
        TURBULENCE INITIAL CONDITIONS: 
          Option = Medium Intensity and Eddy Viscosity Ratio
        END
      END
    END
  END
END
IC:

Code:
FLOW: Flow Analysis 1
  &replace DOMAIN: IC
    Coord Frame = Coord 0
    Domain Type = Fluid
    Location = VOLUMENK_RPER_1_1_SOLID 5
    BOUNDARY: Domain Interface 1 Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = IC_PER1
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        TURBULENCE: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: Domain Interface 1 Side 2
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = IC_PER2
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        TURBULENCE: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: GGI_IC_EMITTER Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = IC_BOTTOM
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Diffuse Fraction = 1.
          Emissivity = 1.
          Option = Opaque
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
      BOUNDARY SOURCE: 
        SOURCES: 
          RADIATION SOURCE: Radiation Source 1
            Option = Isotropic Radiation Flux
            Radiation Flux = RadSourceEmitter
          END
        END
      END
    END
    BOUNDARY: GGI_WINDOW_IC Side 2
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = IC_TOP
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
    END
    BOUNDARY: IC_Wall_Adiabatic
      Boundary Type = WALL
      Create Other Side = Off
      Interface Boundary = Off
      Location = Primitive 2D 5,Primitive 2D C 5,Primitive 2D E 2,Primitive 2D F 2,Primitive 2D H 2,Primitive 2D I 2,Primitive 2D J 2,Primitive 2D K 2,Primitive 2D L 2
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Adiabatic
        END
        MASS AND MOMENTUM: 
          Option = No Slip Wall
        END
        THERMAL RADIATION: 
          Diffuse Fraction = 1.
          Emissivity = 1.
          Option = Opaque
        END
        WALL ROUGHNESS: 
          Option = Smooth Wall
        END
      END
      BOUNDARY SOURCE: 
        SOURCES: 
          RADIATION SOURCE: Radiation Source 1
            Option = Isotropic Radiation Flux
            Radiation Flux = qiso
          END
        END
      END
    END
    DOMAIN MODELS: 
      BUOYANCY MODEL: 
        Buoyancy Reference Density = 1.2922 [kg m^-3]
        Gravity X Component = 0 [m s^-2]
        Gravity Y Component = 0 [m s^-2]
        Gravity Z Component = -9.81 [m s^-2]
        Option = Buoyant
        BUOYANCY REFERENCE LOCATION: 
          Option = Automatic
        END
      END
      DOMAIN MOTION: 
        Option = Stationary
      END
      MESH DEFORMATION: 
        Option = None
      END
      REFERENCE PRESSURE: 
        Reference Pressure = 1 [atm]
      END
    END
    FLUID DEFINITION: Fluid 1
      Material = Air Ideal Gas
      Option = Material Library
      MORPHOLOGY: 
        Option = Continuous Fluid
      END
    END
    FLUID MODELS: 
      COMBUSTION MODEL: 
        Option = None
      END
      HEAT TRANSFER MODEL: 
        Option = Total Energy
      END
      THERMAL RADIATION MODEL: 
        Number of Histories = 10000
        Option = Monte Carlo
        Radiation Transfer Mode = Surface to Surface
        SCATTERING MODEL: 
          Option = None
        END
        SPECTRAL MODEL: 
          Option = Gray
        END
      END
      TURBULENCE MODEL: 
        Option = SST
        BUOYANCY TURBULENCE: 
          Option = None
        END
      END
      TURBULENT WALL FUNCTIONS: 
        High Speed Model = Off
        Option = Automatic
      END
    END
    INITIALISATION: 
      Option = Automatic
      INITIAL CONDITIONS: 
        Velocity Type = Cartesian
        CARTESIAN VELOCITY COMPONENTS: 
          Option = Automatic
        END
        RADIATION INTENSITY: 
          Option = Automatic
        END
        STATIC PRESSURE: 
          Option = Automatic
        END
        TEMPERATURE: 
          Option = Automatic
        END
        TURBULENCE INITIAL CONDITIONS: 
          Option = Medium Intensity and Eddy Viscosity Ratio
        END
      END
    END
  END
END
Window:

Code:
FLOW: Flow Analysis 1
  &replace DOMAIN: WINDOW
    Coord Frame = Coord 0
    Domain Type = Solid
    Location = VOLUMENK_RPER_1_1_SOLID 4
    BOUNDARY: GGI_FDS_WINDOW Side 2
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = WINDOW_TOP
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: GGI_WINDOW_IC Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = WINDOW_BOTTOM
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: WINDOW_PER Side 1
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = WINDOW_PER1
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: WINDOW_PER Side 2
      Boundary Type = INTERFACE
      Interface Boundary = t
      Location = WINDOW_PER2
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Conservative Interface Flux
        END
        THERMAL RADIATION: 
          Option = Conservative Interface Flux
        END
      END
    END
    BOUNDARY: WINDOW_Wall_Adiabatic
      Boundary Type = WALL
      Create Other Side = Off
      Interface Boundary = Off
      Location = Primitive 2D 4
      BOUNDARY CONDITIONS: 
        HEAT TRANSFER: 
          Option = Adiabatic
        END
        THERMAL RADIATION: 
          Diffuse Fraction = 1.
          Emissivity = 1.
          Option = Opaque
        END
      END
    END
    DOMAIN MODELS: 
      DOMAIN MOTION: 
        Option = Stationary
      END
      MESH DEFORMATION: 
        Option = None
      END
    END
    INITIALISATION: 
      Option = Automatic
      INITIAL CONDITIONS: 
        RADIATION INTENSITY: 
          Option = Automatic
        END
        TEMPERATURE: 
          Option = Automatic
        END
      END
    END
    SOLID DEFINITION: Solid 1
      Material = QuartzGlass
      Option = Material Library
      MORPHOLOGY: 
        Option = Continuous Solid
      END
    END
    SOLID MODELS: 
      HEAT TRANSFER MODEL: 
        Option = Thermal Energy
      END
      THERMAL RADIATION MODEL: 
        Number of Histories = 10000
        Option = Monte Carlo
        Radiation Transfer Mode = Participating Media
        SCATTERING MODEL: 
          Option = None
        END
        SPECTRAL MODEL: 
          Option = Gray
        END
      END
    END
  END
END
Interfaces:

Code:
FLOW: Flow Analysis 1
  &replace DOMAIN INTERFACE: GGI_FDS_WINDOW
    Boundary List1 = GGI_FDS_WINDOW Side 1
    Boundary List2 = GGI_FDS_WINDOW Side 2
    Filter Domain List1 = FDS
    Filter Domain List2 = WINDOW
    Interface Region List1 = FDS_MANTLE_IN8
    Interface Region List2 = WINDOW_TOP
    Interface Type = Fluid Solid
    INTERFACE MODELS: 
      Option = General Connection
      FRAME CHANGE: 
        Option = None
      END
      HEAT TRANSFER: 
        Option = Conservative Interface Flux
        HEAT TRANSFER INTERFACE MODEL: 
          Option = None
        END
      END
      PITCH CHANGE: 
        Option = None
      END
      THERMAL RADIATION: 
        Option = Conservative Interface Flux
      END
    END
    MESH CONNECTION: 
      Option = GGI
    END
  END

&replace DOMAIN INTERFACE: GGI_WINDOW_IC
    Boundary List1 = GGI_WINDOW_IC Side 1
    Boundary List2 = GGI_WINDOW_IC Side 2
    Filter Domain List1 = WINDOW
    Filter Domain List2 = IC
    Interface Region List1 = WINDOW_BOTTOM
    Interface Region List2 = IC_TOP
    Interface Type = Fluid Solid
    INTERFACE MODELS: 
      Option = General Connection
      FRAME CHANGE: 
        Option = None
      END
      HEAT TRANSFER: 
        Option = Conservative Interface Flux
        HEAT TRANSFER INTERFACE MODEL: 
          Option = None
        END
      END
      PITCH CHANGE: 
        Option = None
      END
      THERMAL RADIATION: 
        Option = Conservative Interface Flux
      END
    END
    MESH CONNECTION: 
      Option = GGI
    END
  END
END
Thank you very much in advance,
Best, Max
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Old   June 3, 2015, 14:49
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Opaque will become famous soon enough
At a glance, it looks OK..

I noticed a few things:
- Using different turbulence models for each fluid domain, did you turn off "constant domain physics" ? I understand you want to model two different fluids, and a non-trivial setup; however, it is better to know that it runs correctly for the same fluid on both sides with all the physics active, then change the fluid on 1 side

- you are changing the Turbulent Prandtl Number. Do you really need to change such standard value ? Have you validated the heat transfer results for Pr_t = 0.7 ? It is an unusual value to me, and I would be worried about heat transfer results w/o proper validation (did you read CFX heat transfer validation presentation ? what wrong with it ?

- The initial guess for temperature is automatic, I rather setup a isothermal flow everywhere first to see what happens..

As several in the forum advice, get a simpler version of your setup working and increase the complexity later.
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Old   June 4, 2015, 05:34
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Thanks for your suggestions, Opaque, I cleaned up the setup and rerun the simulation, also with a smaller initial pseudo-time step and more MC-samples.

However the error message remains the same, all I can probably know from it is, that the problem is related to the way I set up the radiation model:

Code:
 +--------------------------------------------------------------------+
 |                       Convergence History                          |
 +--------------------------------------------------------------------+

 ======================================================================
 |                        Timescale Information                       |
 ----------------------------------------------------------------------
 |       Equation       |         Type          |      Timescale      |
 +----------------------+-----------------------+---------------------+
 | T-Energy-WINDOW      | Auto Timescale        |     6.26301E+04     |
 | T-Energy-Emitter     | Auto Timescale        |     8.14351E+01     |
 +----------------------+-----------------------+---------------------+

 ======================================================================
 OUTER LOOP ITERATION =    1                    CPU SECONDS = 2.100E+02
 ----------------------------------------------------------------------
 |       Equation       | Rate | RMS Res | Max Res |  Linear Solution |
 +----------------------+------+---------+---------+------------------+
 | Wallscale-FDS        | 0.00 | 4.9E-01 | 1.0E+01 |  5.5  4.3E-07  OK|
 +----------------------+------+---------+---------+------------------+
 | Wallscale-IC         | 0.00 | 5.6E-01 | 1.0E+01 |  5.5  3.7E-07  OK|
 +----------------------+------+---------+---------+------------------+
 | U-Mom-FDS            | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | V-Mom-FDS            | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | W-Mom-FDS            | 0.00 | 6.1E-01 | 1.1E+01 |       9.7E-05  OK|
 | P-Mass-FDS           | 0.00 | 1.5E-09 | 4.3E-08 | 41.9  1.9E+03  F |
 +----------------------+------+---------+---------+------------------+
 | U-Mom-IC             | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | V-Mom-IC             | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | W-Mom-IC             | 0.00 | 7.0E-01 | 1.1E+01 |       2.2E-04  OK|
 | P-Mass-IC            | 0.00 | 1.9E-09 | 2.7E-08 | 42.5  1.1E+04  F |
 +----------------------+------+---------+---------+------------------+
 | U-Mom-OC             | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | V-Mom-OC             | 0.00 | 0.0E+00 | 0.0E+00 |       0.0E+00  OK|
 | W-Mom-OC             | 0.00 | 1.8E+00 | 1.2E+01 |       9.9E-05  OK|
 | P-Mass-OC            | 0.00 | 1.5E-09 | 8.8E-09 | 43.3  9.7E+03  F |
 +----------------------+------+---------+---------+------------------+
Slave:   2   
Slave:   3   
Slave:   3  Details of error:-
Slave:   3  ----------------
Slave:   3  Error detected by routine PSHDIR 
Slave:   3  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG3 
Slave:   3  CRESLT = NONE
Slave:   3   
Slave:   3  Current Directory : /RADIATION/RG6
Slave:   4   
Slave:   5   
Slave:   5  Details of error:-
Slave:   5  ----------------
Slave:   5  Error detected by routine PSHDIR 
Slave:   5  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG3 
Slave:   5  CRESLT = NONE
Slave:   5   
Slave:   5  Current Directory : /RADIATION/RG6
Slave:   2  Details of error:-
Slave:   2  ----------------
Slave:   2  Error detected by routine PSHDIR 
Slave:   2  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG4 
Slave:   2  CRESLT = NONE
Slave:   2   
Slave:   2  Current Directory : /RADIATION/RG6
Slave:   6   
Slave:   6  Details of error:-
Slave:   6  ----------------
Slave:   6  Error detected by routine PSHDIR 
Slave:   6  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG4 
Slave:   6  CRESLT = NONE
Slave:   6   
Slave:   6  Current Directory : /RADIATION/RG6
Slave:   4  Details of error:-
Slave:   4  ----------------
Slave:   4  Error detected by routine PSHDIR 
Slave:   4  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG6 
Slave:   4  CRESLT = NONE
Slave:   4   
Slave:   4  Current Directory : /RADIATION/RG6
Slave:  10   
Slave:  10  Details of error:-
Slave:  10  ----------------
Slave:  10  Error detected by routine PSHDIR 
Slave:  10  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG8 
Slave:  10  CRESLT = NONE
Slave:  10   
Slave:  10  Current Directory : /RADIATION/RG6
Slave:  11   
Slave:  11  Details of error:-
Slave:  11  ----------------
Slave:  11  Error detected by routine PSHDIR 
Slave:  11  CDRNAM = /FLOW/SOLUTION/LATEST/ZN5 /BELG7 
Slave:  11  CRESLT = NONE
Slave:  11   
Slave:  11  Current Directory : /RADIATION/RG6

 Parallel run: Received message from slave
 -----------------------------------------
 Slave partition :        3
 Slave routine   : ErrAction
 Master location : RCVBUF,MSGTAG=1012
 Message label   : 001100279
 Message follows below - : 

 +--------------------------------------------------------------------+
 | ERROR #001100279 has occurred in subroutine ErrAction.             |
 | Message:                                                           |
 | Stopped in routine MEMERR                                          |
 |                                                                    |
 |                                                                    |
 |                                                                    |
 |                                                                    |
 |                                                                    |
 +--------------------------------------------------------------------+

 +--------------------------------------------------------------------+
 |                An error has occurred in cfx5solve:                 |
 |                                                                    |
 | The ANSYS CFX solver exited with return code 1.   No results file  |
 | has been created.                                                  |
 +--------------------------------------------------------------------+

End of solution stage.
I'm happy about any suggestions here, please let me know if I should provide further information!

Best,
Max

Edit: I noticed, I might provide the material definitions as well, maybe there is a problem i don't know about..

Code:
LIBRARY: 
  &replace MATERIAL: QuartzGlass
    Material Group = User
    Option = Pure Substance
    Thermodynamic State = Solid
    PROPERTIES: 
      Option = General Material
      ABSORPTION COEFFICIENT: 
        Absorption Coefficient = 36.2853 [m^-1]
        Option = Value
      END
      EQUATION OF STATE: 
        Density = 2200 [kg m^-3]
        Molar Mass = 60.1 [g mol^-1]
        Option = Value
      END
      REFERENCE STATE: 
        Option = Automatic
      END
      REFRACTIVE INDEX: 
        Option = Value
        Refractive Index = 1.547
      END
      SCATTERING COEFFICIENT: 
        Option = Value
        Scattering Coefficient = 0. [m^-1]
      END
      SPECIFIC HEAT CAPACITY: 
        Option = Value
        Specific Heat Capacity = cpquartz
      END
      TABLE GENERATION: 
        Pressure Extrapolation = On
        Temperature Extrapolation = Yes
      END
      THERMAL CONDUCTIVITY: 
        Option = Value
        Thermal Conductivity = kquartz
      END
    END
  END
END
kquartz and cp quartz are temperature dependent tabulated functions, shouldn't be of much relevance to my problem though.

Last edited by mpeppels; June 4, 2015 at 07:25.
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Old   June 4, 2015, 11:24
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Something is definitely wrong in the setup for the radiation boundary conditions.

To isolate the problem, you can try the following:

1 - Ignore the flow field solutions for now, i.e.
EXPERT PARAMETERS:
solve wallscale = f
solve fluids = f
END

2 - Deactivate radiation in the solid domain. Only leave heat transfer active. Modify boundary conditions at interface appropriately

3 - Run and check if you get at least 2 radiation solution equation sets as you did for the disconnected flow passages. If that still fails, activate radiation only 1 a single fluid domain until you get it to work.
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Old   June 8, 2015, 12:33
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I tried different cases and everything works out, as long as the solid radiation model is deactivated.

But that only tells me that the solid radiation model contains the problem or did I miss the point in your suggestion?
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Old   June 8, 2015, 13:17
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What happens if you activate the radiation model in the solid, but still keep the domain interface boundaries as opaque, i.e. you should get 3 decoupled radiation problems to be solved.

If that works, the problem is with one of the domain interface boundaries. Try activating 1 at a time.

What version of ANSYS CFX are you using ?
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Old   June 10, 2015, 13:07
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I had technical problems yesterday but here I am again today:
Thanks for the debugging guidance so far, I found an interesting result:
The 'malicious' interface isn't even a fluid-solid interface but just a periodicity condition I am using since my geometry is axially symmetric.

I set up this kind of periodic interface for every single domain. Funnily, this is not causing any trouble with all the fluid domains with surface-to-surface radiation models. (However it is, with a solid domain surface-to-surface MC)

Have you ever heard of a similiar problem?
There isn't exactly much to do wrong with this kind of interface I guess, here it is:

Domain Level:

Code:
    BOUNDARY: WINDOW_PER Side 1
       Boundary Type = INTERFACE
       Location = WINDOW_PER1
       BOUNDARY CONDITIONS:
         HEAT TRANSFER:
           Option = Conservative Interface Flux
         END
         THERMAL RADIATION:
           Option = Conservative Interface Flux
         END
       END
     END
     BOUNDARY: WINDOW_PER Side 2
       Boundary Type = INTERFACE
       Location = WINDOW_PER2
       BOUNDARY CONDITIONS:
         HEAT TRANSFER:
           Option = Conservative Interface Flux
         END
         THERMAL RADIATION:
           Option = Conservative Interface Flux
         END
       END
     END
Interface Level:

Code:
   DOMAIN INTERFACE: WINDOW_PER
     Boundary List1 = WINDOW_PER Side 1
     Boundary List2 = WINDOW_PER Side 2
     Interface Type = Solid Solid
     INTERFACE MODELS:
       Option = Rotational Periodicity
       AXIS DEFINITION:
         Option = Coordinate Axis
         Rotation Axis = Coord 0.3
       END
     END
     MESH CONNECTION:
       Option = GGI
     END
   END
Best,
Max
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Old   June 10, 2015, 14:52
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I have not seen such error before.

Though the boundaries are part of a rotational periodic interface , I would try making them "SYMMETRY" boundaries on the solid domain to see if the error goes away.

If the error goes away, it must be a bug in the software.

Hope it helps,
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Old   June 16, 2015, 16:48
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I used a symmetry condition which worked and subsequently tried the periodic condition again which worked as well.

Ripping the setup apart and rebuilding it from scratch might just have been the thing I needed here, even though I did an xxdiff on the solver input ccl of the erroneous version of which I posted the error messages above and the one I got to work now and there really was no difference in the PRE setup..

Result: confused user, resolved problem, alright... :-/

I'd like to ask one more quite basic question since I am new to radiation modelling in CFX and searched the CFX help pages for quite a while without finding anything concrete:

If I define an isotropic radiation source on a fluid-solid interface (fluid: S2S radiation model/solid: no radiation model), I'll do it in the boundary condition in the fluid domain arising from the interface I defined.
Now, I am wondering: what will the source be oriented like? flux from fluid towards solid at positive sign?
I guess, I might have set up a simple test case to find out but I am faithful this easier way might work as well!

(I take it, directional sources with specified flux vector override any kind of flux vector orientation convention?)


Thanks in advance,
Max
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Old   August 22, 2019, 08:30
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Quote:
Originally Posted by Opaque View Post
I have not seen such error before.

Though the boundaries are part of a rotational periodic interface , I would try making them "SYMMETRY" boundaries on the solid domain to see if the error goes away.

If the error goes away, it must be a bug in the software.

Hope it helps,

Hello,


I am using chtMultiRegionSimpleFoam and my OpenFoam version is 4.1



My question is also related to the same topic.

In my geometry I have two regions (as shown in the attached figure)


specifications of my case:



1. Green region is heater.
2. Blue region is air
3. In the heater region, there is fvOptions with a power of 5W.
4. The air is not moving (frozenFlow=yes), to minimize the effect of convection.
5. In the heater region, I have put the radiation model= opaqueSolid.
6. In the air region, I have put the radiation model = viewFactor.
7. I am following the tutorial chtMultiRegionSimpleFoam/multiRegionHeaterRadiation.


Trying to do:

As due to power on the heater, its temperature would be higher as compared to air, so heat will radiate into the air, the goal is to simulate those radiations to check how fast the heat radiates, and how fast it goes to steady state?

Questions:

1. Are the radiation models which I am using correct? Or do I need to use others?
2. When I remove the radiations from my case, even then I see the same results as with radiations. I don't know why is it like that?
3. What should I expect when I am using radiation? faster heat transfer? or something else?
4. With the case specifications, I mentioned above, when I RUN the case, the temperature of both (heater and air) starts continuously increasing and increasing. I don't know why ? because I am just putting 5W of power, the temperature should not go so high.
5. How can I calculate the temperature of my heater if I have the power dissipation of 5W?


I tried to explain my problem and I shall be very thankful if you can help.


Thank you
Attached Images
File Type: png radiation_example.png (15.3 KB, 3 views)
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