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Old   October 10, 2012, 16:08
Default Radiation interface
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jhon fredy hincapie
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as I can model radiation in semitransparent material, in the domain Interfaces between solid and fluid domain, I have no continuity in the heat flux ...
This may be my problem?

I have all the properties of the solid medium,the Refraction Index, Absorption
Coefficient, and Scattering Coefficient ... but I can not get in compliance continudad Interfaces.

who can help me ... I'm more than a month with this problem and I could not give solution
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Old   October 10, 2012, 19:23
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Can you post the output file?
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Old   October 10, 2012, 19:53
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MATERIAL: Air Ideal Gas T
Material Description = Air Ideal Gas (T)
Material Group = Air Data
Option = Pure Substance
Thermodynamic State = Gas
PROPERTIES:
Option = General Material
EQUATION OF STATE:
Molar Mass = 28.96 [kg kmol^-1]
Option = Ideal Gas
END
SPECIFIC HEAT CAPACITY:
Maximum Temperature = 2500 [K]
Minimum Temperature = 290 [K]
Option = Zero Pressure Polynomial
Zero Pressure a1 = 3.5732
Zero Pressure a2 = -7.9639e-4 [K^-1]
Zero Pressure a3 = 2.3717e-6 [K^-2]
Zero Pressure a4 = -1.5164e-9 [K^-3]
Zero Pressure a5 = 3.3254e-13 [K^-4]
END
REFERENCE STATE:
Option = Specified Point
Reference Pressure = 101325 [Pa]
Reference Specific Enthalpy = 0. [J/kg]
Reference Specific Entropy = 0. [J/kg/K]
Reference Temperature = 25 [C]
END
TABLE GENERATION:
Maximum Temperature = 2500 [K]
Minimum Temperature = 290 [K]
Pressure Extrapolation = On
Temperature Extrapolation = Yes
END
DYNAMIC VISCOSITY:
Option = Sutherlands Formula
Reference Temperature = 25 [C]
Reference Viscosity = 1.802e-05 [Pa s]
Sutherlands Constant = 110 [K]
Temperature Exponent = 1.5
END
THERMAL CONDUCTIVITY:
Option = Sutherlands Formula
Reference Temperature = 25 [C]
Reference Thermal Conductivity = 0.0261 [W m^-1 K^-1]
Sutherlands Constant = 110 [K]
Temperature Exponent = 1.5
END
ABSORPTION COEFFICIENT:
Absorption Coefficient = 0.01 [m^-1]
Option = Value
END
REFRACTIVE INDEX:
Option = Value
Refractive Index = 1
END
END
END
MATERIAL: Glass Plate
Material Group = CHT Solids
Option = Pure Substance
Thermodynamic State = Solid
PROPERTIES:
Option = General Material
EQUATION OF STATE:
Density = 2500 [kg m^-3]
Molar Mass = 1 [kg kmol^-1]
Option = Value
END
SPECIFIC HEAT CAPACITY:
Option = Value
Specific Heat Capacity = 7.50E+02 [J kg^-1 K^-1]
END
REFERENCE STATE:
Option = Specified Point
Reference Specific Enthalpy = 0 [J/kg]
Reference Specific Entropy = 0 [J/kg/K]
Reference Temperature = 25 [C]
END
THERMAL CONDUCTIVITY:
Option = Value
Thermal Conductivity = 1.4 [W m^-1 K^-1]
END
ABSORPTION COEFFICIENT:
Absorption Coefficient = 62.11 [m^-1]
Option = Value
END
REFRACTIVE INDEX:
Option = Value
Refractive Index = 1.5
END
END
END
MATERIAL: Glass Wool
Material Group = CHT Solids, Particle Solids
Option = Pure Substance
Thermodynamic State = Solid
PROPERTIES:
Option = General Material
EQUATION OF STATE:
Density = 50 [kg m^-3]
Molar Mass = 1 [kg kmol^-1]
Option = Value
END
SPECIFIC HEAT CAPACITY:
Option = Value
Specific Heat Capacity = 6.70E+02 [J kg^-1 K^-1]
END
REFERENCE STATE:
Option = Specified Point
Reference Specific Enthalpy = 0 [J/kg]
Reference Specific Entropy = 0 [J/kg/K]
Reference Temperature = 25 [C]
END
THERMAL CONDUCTIVITY:
Option = Value
Thermal Conductivity = 0.04 [W m^-1 K^-1]
END
END
END
END

ANALYSIS TYPE:
Option = Steady State
EXTERNAL SOLVER COUPLING:
Option = None
END
END
DOMAIN: Aire
Coord Frame = Coord 0
Domain Type = Fluid
Location = B93
BOUNDARY: Aire Default
Boundary Type = WALL
Location = F105.93,F108.93,F111.93,F179.93,F86.93,F90.93
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Adiabatic
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int ducto ais air Side 1
Boundary Type = INTERFACE
Location = Int ducto air ais
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int entrada cav air Side 1
Boundary Type = INTERFACE
Location = Int entrada cav air
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: Int lateral vid2 air Side 2
Boundary Type = INTERFACE
Location = Int lateral air vid2
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int pared inferior ais air Side 1
Boundary Type = INTERFACE
Location = Int pared inferior air ais
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END

BOUNDARY: Int pared lateral ais air Side 1
Boundary Type = INTERFACE
Location = Int pared lateral air ais
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int pared superior ais air Side 1
Boundary Type = INTERFACE
Location = Int pared superior air ais
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int pared tracera ais air Side 1
Boundary Type = INTERFACE
Location = Int pared tracera air ais
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int salida cav air Side 1
Boundary Type = INTERFACE
Location = Int salida air cav
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: Int vid1 air Side 1
Boundary Type = INTERFACE
Location = Int air vid1
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int vid1 air int Side 2
Boundary Type = INTERFACE
Location = Int air vid1 int
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int vid2 air ext Side 2
Boundary Type = INTERFACE
Location = Int air vid2 ext
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: Int vid2 air int Side 2
Boundary Type = INTERFACE
Location = Int air vid2 int
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Conservative Interface Flux
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: ared inferior aire
Boundary Type = WALL
Location = F109.93,F97.93,F98.93
BOUNDARY CONDITIONS:
HEAT TRANSFER:
Option = Adiabatic
END
MASS AND MOMENTUM:
Option = No Slip Wall
END
THERMAL RADIATION:
Diffuse Fraction = 1.
Emissivity = 0.9
Option = Opaque
END
WALL ROUGHNESS:
Option = Smooth Wall
END
END
END
BOUNDARY: opeening esfera
Boundary Type = OPENING
Location = opening esfera
BOUNDARY CONDITIONS:
FLOW DIRECTION:
Option = Normal to Boundary Condition
END
FLOW REGIME:
Option = Subsonic
END
HEAT TRANSFER:
Opening Temperature = 25 [C]
Option = Opening Temperature
END
MASS AND MOMENTUM:
Option = Opening Pressure and Direction
Relative Pressure = 0 [Pa]
END
THERMAL RADIATION:
Option = Local Temperature
END
TURBULENCE:
Option = Medium Intensity and Eddy Viscosity Ratio
END
END
END
BOUNDARY: opening inferior
Boundary Type = OPENING
Location = opening inferior
BOUNDARY CONDITIONS:
FLOW DIRECTION:
Option = Normal to Boundary Condition
END
FLOW REGIME:
Option = Subsonic
END
HEAT TRANSFER:
Opening Temperature = 25 [C]
Option = Opening Temperature
END
MASS AND MOMENTUM:
Option = Opening Pressure and Direction
Relative Pressure = 0 [Pa]
END
THERMAL RADIATION:
Option = Local Temperature
END
TURBULENCE:
Option = Medium Intensity and Eddy Viscosity Ratio
END
END
END
BOUNDARY: simetria aire
Boundary Type = SYMMETRY
Location = simetria aire
END
DOMAIN MODELS:
BUOYANCY MODEL:
Buoyancy Reference Density = 1.2 [kg m^-3]
Gravity X Component = 0 [m s^-2]
Gravity Y Component = -9.8 [m s^-2]
Gravity Z Component = 0 [m s^-2]
Option = Buoyant
BUOYANCY REFERENCE LOCATION:
Cartesian Coordinates = 0.0[m],0.0[m],0.0[m]
Option = Cartesian Coordinates
END
END
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Old   October 10, 2012, 19:57
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This is another part of the code

DOMAIN INTERFACE: Int lateral vid2 air
Boundary List1 = Int lateral vid2 air Side 1
Boundary List2 = Int lateral vid2 air Side 2
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:
Diffuse Fraction = 1.
Emissivity = 0.87
Option = Opaque
END
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared inferior ais air
Boundary List1 = Int pared inferior ais air Side 1
Boundary List2 = Int pared inferior ais air Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared lateral ais air
Boundary List1 = Int pared lateral ais air Side 1
Boundary List2 = Int pared lateral ais air Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared lateral cav ais
Boundary List1 = Int pared lateral cav ais Side 1
Boundary List2 = Int pared lateral cav ais Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared superior ais air
Boundary List1 = Int pared superior ais air Side 1
Boundary List2 = Int pared superior ais air Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared superior cav ais
Boundary List1 = Int pared superior cav ais Side 1
Boundary List2 = Int pared superior cav ais Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared tracera ais air
Boundary List1 = Int pared tracera ais air Side 1
Boundary List2 = Int pared tracera ais air Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared tracera cav ais
Boundary List1 = Int pared tracera cav ais Side 1
Boundary List2 = Int pared tracera cav ais Side 2
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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared vid1 ais
Boundary List1 = Int pared vid1 ais Side 1
Boundary List2 = Int pared vid1 ais Side 2
Interface Type = Solid 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
END
MESH CONNECTION:
Option = Automatic
END
END
DOMAIN INTERFACE: Int pared vid1 cav
Boundary List1 = Int pared vid1 cav Side 1
Boundary List2 = Int pared vid1 cav Side 2
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:
Diffuse Fraction = 1.
Emissivity = 0.87
Option = Opaque
END
END
MESH CONNECTION:
Option = Automatic
END
END

I do not know if I have a problem with the properties \ general \ .. or if the domain interfaces between solid and fluid donimio.
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Old   October 11, 2012, 07:02
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I cannot see what radiation model you are using. I think you will need a monte carlo model for this model, I suspect the other simpler models will not have sufficient physics.

You have also set the interface condition for all your interfaces to opaque. You probably need to set these to allow radiation transmittion.

But I am no expert in radiation modelling, I could be wrong.
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Old   October 11, 2012, 09:56
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Thanks for your comment
the radiation pattern if Monte Carlos, every body is modeled as opaque, solid body also has that model, according to what I read in the absorption coefficient one can measure the transmission of radiation by the solid body, but not I'm pretty sure.
if you hear anything you tell me. I have a long but I'm working on it
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Old   October 11, 2012, 10:22
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Hello Jhon,

Could you describe a little bit the problem you're trying to solve?

Regards,
Possa
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Old   October 13, 2012, 15:18
Default Problem solver runs the CFX
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whenever a simulation, I get the following message
*
ERROR # 001100279 has occurred in subroutine ErrAction.
Message:
Radiation settings across a coupled model domain were found to be
inconsistent. Please change the setup and re-run.


What is wrong and how I can change the setup?
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Old   October 13, 2012, 18:26
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Hello Jhon,

I think the error message is pretty clear: your settings for the radiation problem are not right. I guess you are making a mistake somewhere in your radiation settings. By taking a quick look in your output file I believe radiation properties are consistent. So I think the problem is probably in interface settings and models.
First of all, as Glenn already said, interfaces between semi-transparent material and other domains must not be opaque.
Are you sure all interfaces are correct?

Regards,
Possa
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Old   October 14, 2012, 12:24
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hello Possa

the settings I am using for the fluid and solid domain are as follows

Fluid domain
-Thermal Radiation
option -> Monte Carlos
-Number of histories
1000000
-Transfer mode
Participating half
Spectral-mode
optio -> Multiband
wavelength in vacuum
0.001 - 2.7 (micron)
2.7 - 1000 (micron)

glass domain
-Thermal Radiation
option -> Monte Carlos
-Number of histories
100,000
-Transfer mode
Participating half
Spectral-mode
optio -> Multiband
wavelength in vacuum
0.001 - 2.7 (micron)
2.7 - 1000 (micron)

Interface type
Fluid - solid
Thermal radiation -> on
conservative interface flux

Material properties aire
Radiation Properties
- refractive index = 1
- Absorption Coefficient = 0.01
- Scattering Coefficient = 0


Material properties vidrio
Radiation Properties
- refractive index = 1.5
- Absorption Coefficient = 61.22
- Scattering Coefficient = 0



I attached a picture of how is the model.
this is my problem, I've read several scientific articles but not the management of CFX tool.

thanks for your attention and help
Attached Images
File Type: jpg Sin título.jpg (56.9 KB, 69 views)
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Old   October 15, 2012, 09:35
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Hello Jhon,

Your settings seem correct.
I've taken a look in your model sketch. If you are modeling all that, then you have a lot of interfaces. Each glass plate has six interfaces. All glass-fluid domain interfaces must be set to thermal radiation->conservative flux. You must be careful to check interfaces below the "interfaces tree" and all domain interfaces related. They all must be conservative flux and not opaque. If you are setting an emissivity is because no radiation is passing through, and that's not what you want.
Cavity walls, on the other hand, must be set to opaque.

Another thing: to model the glass as semitransparent the fluid must be a participating media also and only monte carlo model can be applied in all domains. If you try to use another radiation model for the fluid you won't be able to use thermal radiation-> conservative flux. So all domains must use monte carlo for this to work (learned by experience).

If all interfaces are correct it should run.

Regards,
Possa
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Old   October 18, 2012, 18:33
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hello Possa

and finish the simulation, thank you for your cooperation and others. I attached a picture of how the simulation gave. The parameters used were as you mentioned earlier.
I have only one question. for semitrasmaparente material has the following properties, absorptivity (0.14) - reflectivity (0.08) - transmisivity (0.78) more Emissivity (0.85) where you enter the value of emissivity in CFX, CFX progrma or it assumes by default?

thank you very much for your collaboration, were more than three months of work and information search.

if you see something strange in the pictures I can tell my.
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File Type: jpg radiation.jpg (87.3 KB, 59 views)
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Old   October 19, 2012, 15:29
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Hello Jhon,

For any participating media (including semi-transparent) emissivity is not needed to solve the radiation problem as it is derived from the absorption coefficient (not absorptivity).

You only use emissivity, absorptivity, reflectivity and transmisivity for a participating media if you are treating it as a whole piece (example: solving a glass wall without solving the radiation inside the glass only the energy balance on the wall).

What you need to set for participating media is absorption coefficient, refraction index and scattering coefficient.

If you need any clarifying on the subject I suggest the book "Radiative Heat Transfer" from Siegel and Howell.

Regards,
Possa
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Old   November 10, 2013, 02:39
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Hi dear all,
i have to model super heater tube bundles in cfx.
How i can consider the radiation?
please guide me step to step!!!!!!
thanks a lot
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Old   November 10, 2013, 05:32
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Glenn Horrocks
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The simple approach is to model it as a simple heat load.

Or you can use a radiation model. The discrete transfer model is adequate for many applications. Have a look at the tutorials for how to set it up.
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Old   January 26, 2014, 18:11
Question Different Fluids In CFX
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Hassan Adel
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I put different Fluids domain in CFX, but when I run it
Error appears
+--------------------------------------------------------------------+
| ERROR #001100279 has occurred in subroutine ErrAction. |
| Message: |
| Equation subsystem: "Momentum and Mass - 1" has not been found on |
| both sides of interface "Default Fluid Fluid Interface". Check t- |
| hat you have set consistent physics across all domains that use t- |
| his interface. |
| |
| |
+--------------------------------------------------------------------+

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

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