inflation layers

- July 13, 2020 at 3:46 am
  
  abdulrahman86
  Subscriber
  
  Hi,
  
  I am modeling a building inside a fluid domain to test the effect of wind on it, I generated a structured mesh and it has a reasonable quality but when I add the inflation layers to the intended surfaces the element quality of these surfaces decreases and the aspect ratio increases. The other quality measures are alright orthogonal value 0.38, max skewness 0.5
  
  I am not getting a convergence so I thought that might be the case, any ideas?
  
  Thanks
- July 13, 2020 at 4:10 am
  
  Keyur Kanade
  Ansys Employee
  
  Orthogonal quality looks ok.
  
  Please cross - check your inlet and outlet boundary conditions in fluent.
  
  Regards,
  
  Keyur
  
  If this helps, please mark this post as 'Is Solution' to help others.
  
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- July 13, 2020 at 4:21 am
  
  abdulrahman86
  Subscriber
  
  Thank you for your response In fluent I did the following:
  
  *K-epslon with enhanced wall treatment
  
  *inlet as velocity inlet with constant speed
  
  *outlet as pressure outlet
  
  * Ground and building as walls
  
  * defined reference values
  
  rest are default, but no convergence, continuity flattened around 1e-1
- July 14, 2020 at 3:33 am
  
  Keyur Kanade
  Ansys Employee
  
  If you are using k-e eht, then please make sure that you have refined mesh near walls.
  
  what is inlet velocity?
  
  can you please insert image of mesh near wall.
  
  you should have good boundary layer / inflation.
  
  Regards,
  
  Keyur
  
  If this helps, please mark this post as 'Is Solution' to help others.
  
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- July 14, 2020 at 10:39 pm
  
  abdulrahman86
  Subscriber
  
  I think the mesh near the walls has an issue, although the minimum orthogonal quality increased when I refined the mesh to become 0.7 the inflation layers are not showing in the intended faces except for one as shown in the attached pictures. All crosses in the pictures should have inflation layers similar to the one in the top of the building
  
  The inflation layers reappear when I use the same number of division on all edges but that reduces the quality measures i.e. orthogonal around 2e-2
  
  My inlet velocity is 14.5 m/s resulting in Re around 1.8e5
- July 15, 2020 at 5:04 am
  
  Keyur Kanade
  Ansys Employee
  
  With inflation 2e-2 is not that bad quality. I think you may proceed to run.
  
  Regards,
  
  Keyur
  
  If this helps, please mark this post as 'Is Solution' to help others.
  
  Guidelines on the Student Community
  
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