Previously was having alot of problems meshing the prism layers… ( Boundary Layer Does Not Form - Except When Default Settings Used ) After seemingly resolving that… now, it seems that the MRF isn’t spinning during simulation. i have taken a look at many MRF setups and think I have set it up just lik…

Hi @cweisheng , When you mention that you want to check whether the MRF spins early on or not I have the impression that you might be misinterpreting what the MRF actually does. It will not spin. The mesh will not move at all; that’s why it is a steady-state approach that simulates rotation by addi…

Thanks. I understand it does not physically spin but the flow velocity should be “spinning” and so I should see some swirl in the flow particles? The planar cut through the propeller seems to suggest it is generating some thrust with the pressure field [image] And there is momentum imparted to t…

In the images you can see some discontinuity between the MRF zone and the rest of the volume. Also, if you have a look at the Zone mesh, you’ll see that the edges have not been properly captured. Add a feature refinement, in order to better capture the edges of the cylinder. [image]

Hi, Please check this: [image] Import of additional solid volumes into a CAD scene Further, please make sure that the name of the cell zone does not start with a number and does not contain spaces. For example, valid names would be “MRFZone”, “MRFZone_1”, “rotating_cells” and Not “1MRFZone”, “M…

Thanks for your suggestions: @pfernandez and @Retsam Based on the screenshots I have sent, are you able to opine if the MRF is working? I still think there should be flow rotation/swirl?

Yes I have checked… doesn’t seem like naming convention is the problem: [image] Still no swirl.

I think I missed something, why are your BMB tunnel walls listed as symmetry boundary conditions, what about slip walls on BMB tunnel?

@DaleKramer asks good question: set BMB walls to slippy walls (except inlet and outlet). Moreover, in ‘Materials’ you need to specify as ‘Air’ only ‘region0’. When you decided to use full resolution for propeller?

Thanks all. I think I missed something, why are your BMB tunnel walls listed as symmetry boundary conditions, what about slip walls on BMB tunnel? → I used to do them as symmetry (another software) and the results were ok. I can set them to slip walls I guess. Moreover, in ‘Materials’ you nee…

SimScale CAE Forum

MRF not spinning

Project Support

Retsam April 23, 2019, 10:25am 8

Hi,

You use particles trace and you see by yourself that flow does n ot rotate. Did you checked your naming convention, please?

Retsam