[bikooo3878]

Hello Everyone,

I am trying to simulate the movement of a pressure relief valve. I've written a UDF for the valve movement and used spring function from the 6DOF settings. However, why is it when I define the triads zone as deforming it leads to instant divergence as shown, and when I define only the stationary boundaries and the valve it works perfectly well!.

https://drive.google.com/open?id=1-f...KYvpvVF2D-t6ah

https://drive.google.com/open?id=1Zf...zqjLInlmwMmAVM

you can also download the archived project from here if it helps.

My setup should be similar to that in this tutorial. So, if anyone can explain to me what am I doing wrong or missing I'd be very grateful

thank you

[bikooo3878]

I know this geometry will lead to reversed flow, but I'm just interested in these holes that appear in the mesh at the moment.

[bikooo3878]

Heads up!!

I've been trying to find out what's wrong for several days now and finally it worked!

most probably it was due to the reason I named a zone "deforming_zone" to set it as deforming (obviously). This led to fluent creating an interior-deforming_zone and my "deforming zone", which when was set as deforming...there was no error

Also seems that when I am not defining any deforming zone, fluent auto-detects triads zone and apply a deforming region to it, but I'm not sure

Just glad it worked!

[vinerm]

You understood it correctly. Fluent does not expect users to define any cell zone as deforming. Only the boundary zones should be deforming. Cell zone deformation is determined by Fluent using boundary deformation and the method(s) selected out of remeshing, smoothing, and/or layering.