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Adding a new dependent variable in a 2D axial symmetry NS problem
Posted Feb 29, 2012, 8:19 a.m. EST Fluid & Heat Version 4.2a 2 Replies
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Hello
I'm working on a particular case that requires to add a new dependent variable.
Actually, my problem is a 2D axial symmetry one. So i have to calculate the radial and axial velocity and the pressure. They depend on the r and z coordinates only. However, in my problem i also need to take in account the azimuthal velocity that also depends on the r and z coordinates only.
So i want to add this azimuthal velocity and the corresponding equations in the Equation System Subdomain Settings ( i need to add an equation that correspond to the navier stoke equation along the azimuthal coordinate).
Is it possible to do this ? (because when i'm adding a dependent variable in the model navigator i get an error)
Thank you for your help
Etienne
I'm working on a particular case that requires to add a new dependent variable.
Actually, my problem is a 2D axial symmetry one. So i have to calculate the radial and axial velocity and the pressure. They depend on the r and z coordinates only. However, in my problem i also need to take in account the azimuthal velocity that also depends on the r and z coordinates only.
So i want to add this azimuthal velocity and the corresponding equations in the Equation System Subdomain Settings ( i need to add an equation that correspond to the navier stoke equation along the azimuthal coordinate).
Is it possible to do this ? (because when i'm adding a dependent variable in the model navigator i get an error)
Thank you for your help
Etienne
2 Replies Last Post Feb 29, 2012, 11:56 a.m. EST
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Posted:
1 decade ago
If there is a variation in the azimuthal angle, I don't think you can consider it 2D axial symmetric anymore, you will have to go to 3D.
In other words, if there is a circular motion around the line of symmetry, it will need to be modelled using a 3D model.
-Jaap
In other words, if there is a circular motion around the line of symmetry, it will need to be modelled using a 3D model.
-Jaap
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Posted:
1 decade ago
But i don't have variation in the azimuthal angle.
I just have an azimuthal velocity and i would like to add this variable too input the effect of that velocity my Navier Stokes equations.
(My only simplification in the NS cylindrical equations is that d/dtheta - the variation of the variables along the azimuthal coordinate- is zero)
I just have an azimuthal velocity and i would like to add this variable too input the effect of that velocity my Navier Stokes equations.
(My only simplification in the NS cylindrical equations is that d/dtheta - the variation of the variables along the azimuthal coordinate- is zero)