Dynamic Mesh Adaptation : SBES

- October 28, 2021 at 10:45 am
  
  Bibill
  Subscriber
  
  Dear all,
  I'd like to reproduce a dynamic mesh adaption methodology introduced in the conference proceedings Dynamic Mesh Adaptation for Scale-Resolving Reacting Flow Simulations (2021) - Yu Xia et al. (Ansys).
  In the present paper, they impose a refinement/coarsening of the mesh based on the LES index defined in equations (2,3,4) with the conditions (6a,6b).
- October 28, 2021 at 12:29 pm
  
  aitor.amatriain
  Subscriber
  
  You can access to the value of velocity components at the previous time step
  3.2.3. Cell Macros (ansys.com)
  so the mean value is obtained from the definition. The same applies to I.
- October 28, 2021 at 1:09 pm
  
  Bibill
  Subscriber
  
  Hi Aitor, thank you for your fast answer.
  If I understood well, is the mean velocity component obtained by averaging over 2 time-steps then?
- October 28, 2021 at 1:37 pm
  
  aitor.amatriain
  Subscriber
  
  No. Let's say that you have simulated n-1 time steps. Then, the mean value of a variable called U is:
  The value of the previous expression is known, so the mean value of U at t=t_n is:
  In fact, you do not need the values of the variables the previous time step. You only need to create a Custom Field Function/UDM to then rewrite the value at each time step.
- October 28, 2021 at 2:49 pm
  
  Bibill
  Subscriber
  
  Ok, great I understood! Yes, indeed we do not need the previous time step value then!
  
  Thank you very much, Aitor!
- October 29, 2021 at 6:47 am
  
  aitor.amatriain
  Subscriber
  
  You are welcome!