how the under relaxation factors will effect convergence or results?

  • 28 Views
  • Last Post 07 May 2020
  • Topic Is Solved
Weiqiang Liu posted this 05 May 2020

Hi all,

I am calculating a propane catalytic combustion with single step surface and gas reaction scheme. I set the under relaxation of energy to 0.8 and monitor temperature  seems keeps unchanged after a huge number of iterations. 

when I modified the under relaxation factor of energy to 0.9, the monitor temperature would increase 100 k higher and keep constant. when I further increase energy under relaxation factor, the monitor temperature would go higher. when I set the under relaxation factor to 1, the case diverged immediately.

I wonder how under relaxation factors will effect results and convergence. How can I determine the case is fully converged?

Weiqiang 

Order By: Standard | Newest | Votes
Kalyan Goparaju posted this 05 May 2020

Hello Weiqiang, 

The discussion presented in this page might help you understand the idea of under-relaxation.

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v201/en/flu_th/flu_th_sec_time_theory_seg.html%23flu_th_sec_underrelax_eqn

Thanks, 

Kalyan

Weiqiang Liu posted this 07 May 2020

hi Kalyan,

Thanks for your sharing.

Best regards

Weiqiang

Close