MRF Rotating Issue with axis

Im trying to rotating a celling fan in room with inlet velocity from window and outlet pressure from door,
But some issues came out:

  1. The rotating axis could not be change, while im trying to move it to the center of the room.
  2. The result of velocity vector can not be right,

Hello HSN,
thanks for reaching out to us here in the forum.

Can you please provide us with a link to your project so that we can have a look at your setup.
Also you may want to have a look at this page, which explains the setup of MRF:

Best regards

Hi SBlock
Thank you so much for your reply,
I’m following this article but I couldn’t solve it.
Here is my project


When i have a look at your project, I notice that the room is very small. Is this in the right scale?

You can either scale the model in the edit in case mode or change the model unit while importing the model.

Cad Mode:

Model Unit on Import:

For the size of the model,
usually I do a scale down just to save the time.
But I guess this id not the issue, right?


Okay in regards to your question, I had a look at other projects,
and as long as the point is in the right location your simulation should be fine. The MRF zone will use this at the center of rotation.
The Vector/rotating Axis itself will always stay at the global coordinate system. Please use the right-hand rule to define the positive rotation direction to determine if your object is spinning the right way around.

So I would say that your setup is fine.

Best regards Sebastian

Hi SBlock

Thank you so much,
I did the same cnter of rotation for other simulation but the result is not right,
I was trying to use the AMI zone but the failure was their of every try.
Is there any a quick or even long course for how to be an expert on SIMCSALE

Hello HSN,
the best way to learn SimScale is to use the platform make your own mistakes and learn from them.

In addition to that, there are a lot of Tutorials and Webinars on the Website.


Also, it’s always good to learn something about the fundamentals so having a look at the documentation also always helps.

Best regards

Hi SBlock
Regarding the result I have got, the room is not being effect it by the fan rotation.
What do you think is the issue


For me, it seems quite right,
are you sure the vent is turning in the right direction?

Best regards

Hi SBlock,
Actually I used both direction and the result are smaller.

Here you can find a some pictures of the existing models smaller to what we doing right now.

Are you sure that you have the right simulation geometry,
For me, the results seem quite possible for a flat blade. Usually, these blades are at an angle so that the air is getting “pushed” up or downwards. which you can also see in the figures of the reference.

Best regards

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