How to customize the nature of the material in Code Saturne?

Forums code_saturne usage
1

Hello Sir,

In fact, I want to simulate hot air through a nozzle to dry a carton, but I can’t find how to customize the nature of the material in Code Saturne, so I can’t define the nature of the carton.

In the user’s guide, I did not find the description or function of each part or section in Code Saturne, but just the language Fortran, so where can I find the description or function.

Thank you very much

Kinds Regards

XING Jian

2

Hello,

Which version of the code are you using ? Did you check the user examples in the Docygen documentation ? Did you check for physical property settings in the GUI ?

Also, is the carton handled as a boundary (in which case you probably need to handle it with exchange coefficients, or conjugate heat transfer), or a porous medium (in which case you need to have a model for this) ?

Regards,

Yvan

3

Hello,

Yes, the carton is handled as a boundary, I need to handle it with exchange coefficients.

I am using Code_Saturne 4.0.6, and I didn’t check user examples in the Doxygen documentation yet, because I thought I could add and define new material directly in Code_Saturne. So, If I want to do this, do I have to learn and edit the fortran language in cs_user_boundary_conditions.f90?

And in the GUI, there is all fortran language, is there any other GUI about functional descriptions for each part or section of Code_Saturne?

Thanks very much

Kinds Regards

XING Jian

4

Hello,

You do not need user Fortran subroutines if you simply define the exchange coefficient with the boundary conditions in the GUI.

Regards,

Yvan

5

Hello,

Thank you for your prompt response.
Actually, I don’t just need the exchange coefficient, but also need to define the density, specific heat, thermal conductivity, and heat transfer coefficient( I am not sure if this is exchange coefficient) of the carton. Also, I need to define the nature of the wall which is made by steel. If I want to do these, do I have to learn and edit the fortran language in cs_user_boundary_conditions.f90?

And I have one more question, what’s the meaning of ‘Prescribed flux’ in the Thermal Type of Boundary conditions? If the flux is equal to 0, does it mean that there is no heat exchange?

Thanks again

Kinds Regards

XING Jian

6

Hello Yvan,

I still have a question about Periodic Boundaries, I know ‘Selection criteria’ is name of the Boundaries Condition, and ‘Plane’ is ID of the face, but I don’t know the meaning of ‘Fraction’ ‘Verbosity’ and ‘Visualization’.
I want to do make a Periodic Boundary, by using two symmetrical faces, can I do like this:

Fraction    Plane   Verbosity   Visualization   Selection criteria
0.99           89         1               1              Symmetry_1
0.99           43         1               1              Symmetry_2

When I run the calculation, it always shows : Joining operation is non-conforming.

Thanks very much

Kinds Regards

XING Jian

7

Hello,

No, the plane argument has no relation to a face id, bu is an angle used for curved surfaces.

Alsi, if Symmetry_1 is periodic with Symmetry_2, you should use both in the same definition using “Symmetry_1 or Symmetry_2”.

Non-conforming periodicity is OK, though it slightly degrades mesh quality.

Regards,

Yvan
Yvan

8

Hello Yvan,

So you mean the plane is an angle used for curved surfaces, if Symmetry_1 is periodic with Symmetry_2(I have already defined these two faces in the same boundary condition.)，is it the angle between the two faces? And in my condition, these two faces are parallel (We can not set the angle to 0 as specified), so we should set the angle to how much?

Then I still do not understand ‘Fraction’ ‘Verbosity’ and ‘Visualization’. What is this fraction about?

Thanks very much

Kinds Regards

XING Jian

9

Hello,

Check the user’s guide pdf, p49 (for version 5.0).

Regards,

Yvan

10

Hello Yvan,

Thank you very much, I made it through your help, just a little question, like Symmetry_1 is periodic with Symmetry_2, the distance between them is 0.09m and they are parallel, (The coordinate of the x-axis of Symmetry_1 is 0.045 and Symmetry_2 is -0.045), so they are type of Periodicity by translation, but the Translation vector: Tx should be 0.09 or -0.09？I have tried these two, both of them could be successful, but the results were different, so I should use which one?

Thank you very much

Best Regards

XING Jian

11

Hello,

Either one should work. Only the mesh numbering should be different.

Best regards,

Yvan

12

Hello Yvan,

Sorry, I do not quite understand what ‘mesh numbering’ means. Are they ‘Symmetry 1’ and ‘Symmetry 2’ which is periodic BC?

Thank you very much

Best Regards

XING Jian

13

Hello,

Mesh numbering is an internal property, so you can ignore it.

You need both Symmetry1 and Symmetry2 in you selection criteria, which implies a logical “or”:

“Symmetry1 or Symmetry2”

Regards,

Yvan

14

Hello Yvan,

Excuse me for giving you so much trouble, thanks, two more questions, what is the unit for Exchange coefficient which is in the boundary conditions in the GUI? And what’s the meaning of ‘Prescribed flux’ in the Thermal Type of Boundary conditions? If the flux is equal to 0, does it mean that there is no heat exchange?

Thank you very much

Best Regards

XING Jian

15

Hello,

The units should be in international system units (with flux in W/m2 = h(delta T)).

And yes, 0 flux = adiabatic.

Regards,

Yvan