Decreasing transient continuity residual peak value

- August 19, 2020 at 2:40 pm
  
  ALEXANDRE COSTA
  Subscriber
  
  Hi All
  Can anybody share some ideas about decreasing the peak values of continuity residual for a transient simulation ?
  It is going like the picture :
- August 19, 2020 at 3:23 pm
  
  Rob
  Forum Moderator
  
  How many iterations are you needing per time step? Aim to converge a step in 10-15 iterations. n
- August 20, 2020 at 12:30 pm
  
  ALEXANDRE COSTA
  Subscriber
  
  Hi Rob,nNow things are getting worse. The continuity residuals are exploding after being stable for several thousands iterations (see picture)nAny clue for workarounds ?nn
- August 20, 2020 at 1:41 pm
  
  DrAmine
  Ansys Employee
  
  It looks like you are using Windkessel ACT?n Now it is hard to say what can be done here: I will first check mesh, boundaries if all is consistent and try using smaller time step size. Does it diverge without using that Windkessel Model?n
- August 26, 2020 at 2:23 pm
  
  ALEXANDRE COSTA
  Subscriber
  
  Hi DrAminenThanks for the output.nIf I replace for a simple pressure outlet, it goes. Unfortunatelly, I should use windkessel for a more realistic simulation. n
- August 26, 2020 at 4:25 pm
  
  DrAmine
  Ansys Employee
  
  You might need to add more relaxation and/or adjusting the windkessel UDF's. You might code that on your own using your own UDF or some expressions.n
  - November 18, 2022 at 8:56 am
    pen m
    Subscriber
    Hello, you have the code of the Windkessel model. There are some problems in the code I wrote. If possible, please send it to my email 972539894@qq.com, thank you.