[mitsushi]

Hello zCFD team,

I would like to model a rotating geometry either with
- rotating reference frame (steady-state condition), or
- rigid body, moving mesh (transient condition).
in zCFD.

I suppose that the set-ups involved are:
- set the interface between the rotating and the surrounding stationary domains
- set the rotating condition either reference frame or moving mesh.

I can not find how to set up such conditions in the documentation or validation samples.

Would you please teach me? A very simple input sample file would be very helpful.

Regards,
Mitsushi

[mallan]

Hello Mitsushi,

First of all, at present zCFD only supports "frozen rotor" steady state simulations, however we're nearing completion on our overset capability which will allow time accurate rotating domains.

In order to set up rotating domains for frozen rotor simulations, you first need to create a mesh with the rotating domains "tagged" in the CFD mesh, such that they can be selected as rotating domains. After that, the set up is simply a case of selecting the fluid zones and defining their properties. Below is an example of the python code which would set up two counter rotating zones (rotation around the y-axis with axis offset). The zone number is that given to the volume during mesh conversion.

'FZ_1' : {
'type' : 'rotating',
'zone' : [15],
'axis' : [0.0, 1.0, 0.0],
'origin' : [0.5, 0.0, 7.5],
'omega' : -1.64,
},

'FZ_2' : {
'type' : 'rotating',
'zone' : [16],
'axis' : [0.0, 1.0, 0.0],
'origin' : [0.5, 0.0, -7.5],
'omega' : 1.64,
},

All walls within these zones, will rotate at the same angular velocity as the rotating volume. I've set up a mesh that uses this example, which I will send details for you to download.

Regards,

Mark.