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…

[image] cweisheng: I used to do them as symmetry (another software) and the results were ok. I can set them to slip walls I guess. Well, I did not discovered that use of symmetry wall, as documentation of SymScale states: The symmetry boundary condition defines a mirror face/surface. The sy…

So last night, tried to start at lower rad/s --> same outcome. Just changed to slip walls for the boundaries --> same outcome. Wanted to try high y+ but didn’t have time to fix the mesh yet.

[image] cweisheng: So last night, tried to start at lower rad/s –> same outcome. The first idea is would not fly. Lower or higher rpm is not the culprit. [image] cweisheng: Just changed to slip walls for the boundaries –> same outcome. You symmetry boundary without the role of being a…

One more thing, @cweisheng . In order to short you simulation time, I suggest following setup, until culprit is found: Set Inlet flow to 0, no wind from front, for the moment. In ‘Result control’ > ‘Surface data’ use your Outlet wall to gather the Forces Set simulation to ~ 50 steps. Now, when MRF …

Actually I have been very successful in the other software - not just MRF but actual rotating propeller on unsteady flow, and even with close-by aircraft fuselage. We validated the trends with wind tunnel data as well, be it for propeller alone or propeller with body. Which is why I’m struggling to …

Where is the outlet? (have not looked at project recently but just that weird image :wink: )

Its at the bottom of the box as per above picture. Can I check where should the material point be? Inside the MRF cylinder or outside? And I generated the mesh with it being INSIDE the MRF. If now I need to move it outside the MRF, do I need to remesh?

Well, MRF works. do not touch your material point. Check your top / bottom walls verify the Forces and proceed from that moment on.

Why do you say MRF works? Well, I mean it looks like it is driving the flow down… but it doesn’t look right.

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MRF not spinning

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cweisheng April 25, 2019, 3:26pm 18

Took one of your suggestions… to run with 0m/s inlet… Must say I was not expecting this at all…

Hmmmm… what the… Anyone?

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