Mesh sizing leads to negative cell volume

- July 19, 2018 at 3:43 pm
  
  ewold
  Subscriber
  
  Hello.
  
  I am running a 2 way FSI simulation and recently tried to decrease the element size in my fluid mesh. Before I did this, I was operating on a fairly low mesh resolution and everything worked as expected. Whenever I try to raise the resolution I receive the negative cell volume error. Is there a way to fix this without decreasing the magnitude of my load or decreasing the timestep?
  
  Thanks
- July 19, 2018 at 4:55 pm
  
  KR
  Administrator
  
  Hello,
  
  Could you please clarify in which tool you are seeing the negative volume error - Fluent or mechanical? If you are seeing this error in Fluent, you might want to check your dynamic mesh set-up. Perhaps, the time step size is large. Or perhaps you are seeing large deformations (deformations should be smaller than one cell 'height' on a per-timestep basis). Does this happen at the beginning of your simulation (right after 1st r 2nd iteration) or during it?
  
  Please post some more details (along with some images).
  
  Thank you.
  
  Best,
  Karthik
- July 23, 2018 at 3:16 pm
  
  ewold
  Subscriber
  
  I was able to resolve the issue thanks to your response.
- October 10, 2018 at 2:04 pm
  
  Aparna
  Subscriber
  
  i am also facing the same problem. how you resolved it. kindly help me. im simulating scroll expander.
- October 11, 2018 at 4:49 am
  
  Aparna
  Subscriber
  
  i am also facing the same problem. how you resolved it. kindly help me. im simulating scroll expander.
- October 11, 2018 at 4:49 am
  
  Aparna
  Subscriber
  
  i am also facing the same problem. how you resolved it. kindly help me. im simulating scroll expander.
- October 11, 2018 at 9:46 am
  
  Rob
  Ansys Employee
  
  You might be better served by starting a new thread and including images of the geometry & mesh.
- June 20, 2020 at 9:55 am
  
  FarhanMuhib
  Subscriber
  
  @ewold, can you please help me solve the problem? I am having the same problem. Thanks

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