[pechwang]

Hello everyone,

Right now I'm using MRFSimpleFoam to run a very simple lubrication model. So I need topoSet to select a cellset and put it into the rotating MRFzone. I use cylinderToCell to select the cells. Part of the code is like this

name rotor;
type cellset;
action new;
source cylinderToCell;
sourceInfo
{
P1 (0 0 0);
P2 (0 0 0.127)
radius 104.4;
}

In this situation, I can select all the cells (I have 10 cell layers in the z direction) in the domain and it works perfect. However, right now I want to put part of the cells (maybe 5 layers or less) in the rotating reference frame. And I change the position of P2. Unfortunately, it cannot give me a correct answer. It gives me either 0 or 5400. 5400 is total number of cells in my domain. This really drives me crazy. I want to know whether you have any experience with MRFsolvers or topoSet utilities. Can you give me a hand?
Thanks

[Prosper]

I have a similar problem with cylinderToCell and I also wanna know the answer.

Best,

Originally Posted by pechwang

Hello everyone,

Right now I'm using MRFSimpleFoam to run a very simple lubrication model. So I need topoSet to select a cellset and put it into the rotating MRFzone. I use cylinderToCell to select the cells. Part of the code is like this

name rotor;
type cellset;
action new;
source cylinderToCell;
sourceInfo
{
P1 (0 0 0);
P2 (0 0 0.127)
radius 104.4;
}

In this situation, I can select all the cells (I have 10 cell layers in the z direction) in the domain and it works perfect. However, right now I want to put part of the cells (maybe 5 layers or less) in the rotating reference frame. And I change the position of P2. Unfortunately, it cannot give me a correct answer. It gives me either 0 or 5400. 5400 is total number of cells in my domain. This really drives me crazy. I want to know whether you have any experience with MRFsolvers or topoSet utilities. Can you give me a hand?
Thanks

[pechwang]

Hi Prosper,

It seems like I have found the answer. The unit of my mesh file is in mm. So in blockMeshDict file, I use convertToMeters at the very beginning. And I do the same thing in topoSetDict file. However, it seems like convertToMeters does not work in topoSetDict. After I change the unit to m, everything is OK. Since you have the same problem, maybe you also use other units instead of meters. So I think the problem now becomes why convertToMeters does not work in topoSetDict file. What do you think?

Thanks,
Pengchuan

[Prosper]

Originally Posted by pechwang

Hi Prosper,

It seems like I have found the answer. The unit of my mesh file is in mm. So in blockMeshDict file, I use convertToMeters at the very beginning. And I do the same thing in topoSetDict file. However, it seems like convertToMeters does not work in topoSetDict. After I change the unit to m, everything is OK. Since you have the same problem, maybe you also use other units instead of meters. So I think the problem now becomes why convertToMeters does not work in topoSetDict file. What do you think?

Thanks,
Pengchuan

Thank you for your reply!

I see. Maybe I'll need to change all the units in my problem and try it again.

Best,

[Ben UWIHANGANYE]

Dear Wang and Prosper,

May you help to know what i am missing in my toposetDict. I am not getting the cylinder i need in paraview.

you may find attached folder for my setup.

I will be happy to get your support!


Thank you!

[pechwang]

Hi Ben,

May I know the reason why you want this cylinder? What's the purpose of that? Besides that, the size of your cylinder is kind of small, even smaller than the size of your mesh cell. So the topoSet cannot select the cells. You can try to change the size of your cylinder.

Thanks,
Pengchuan

[Ben UWIHANGANYE]

I want to simulate the flow past that cylinder(Stationary &Oscillating). I have succeeded with mapping that cylinder. Now what i am asking: is it possible to move that cylinder using setFiedsDict? thx.