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?

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

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?

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MRF not spinning

Project Support

anirudh2821998 April 21, 2019, 9:03am 2

Hi @cweisheng

I will take a look at the problem as soon as I am free and come back with a suitable solution.

Thanks
Ani

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