[papamichous]

Hi,
How can I use cylindrical coordinates in ANSYS CFX?

[Thomas MADELEINE]

Hi,
your question is quite large...
When you have defined your axis you can access to the radius and theta variables.
See any tutorial in turbomachinery (tuto #14 for instance) to have an example.

[papamichous]

Hi,
i want simulate this case of water flow through a porous media

[Thomas MADELEINE]

So if you want to simulate without the standpipes you have a rotationnal symmetry.
So you can define only a part of the domain (1/6 => 60° for instance) and use the axis to define your symmetry. You will have a radius variable in CFX Pre.

In the case you want to keep your standpipes (it can affect the flow), you don't have any symmetry so you wille have to define the whole domain and I don't know how create an axis...
In this case I will probably use a very ugly method by create my own radius expression...
for instance if you axis is z:
Radius = sqrt((x-x0)²+(y-y0)²)
Theta = atan(y/x)*step(x)+(atan(y/x)+180)*step(-x)
or something equivalent

[papamichous]

can you create the geometry for me for both?

[Thomas MADELEINE]

Hi,
I am sorry but I can't create the geometry...
But I don't think it is really complex... you can create a cylinder a cut it into three pieces...
Then for the one with standpipe:
you add two small cylinders.
For the symmetric one:
you cut every thing by an angle of your choice (45° or 60° sounds correct to me)
Normally any 3D CAD software can handle it

[papamichous]

how can I represent the shear stress between the fluid medium and the porous medium?