improve the stability of a numerical scheme

- December 8, 2020 at 7:58 pm
  
  manelaero2020
  Subscriber
  
  Hi freinds ;
  1/ If the curves of residuals are oscillating ( please see attached figure) ; so is it true to say that my numerical scheme is INSTABLE ?
  2/ In the order to improve the stability of my numerical scheme ( second order upwind + K epsilon RNG for turbulence) and accelerate convergence ; it is a good solution to switch to unsteasy temporel model and decrease the time step ?
  
  Thanks you
- December 9, 2020 at 4:33 am
  
  Keyur Kanade
  Ansys Employee
  
  If physics you are solving is inherently transient then you will have to use unsteady solver. nOscillating residuals does not necessarily mean that numerical scheme is unstable. It may depend on your inputs. nAlso please check mesh. Make sure that you sufficient mesh refinement at the areas interested. nYou can find numerical scheme related information at nnRegards,nKeyurnHow to access Ansys Online Help DocumentnHow to show full resolution imagenGuidelines on the Student CommunitynHow to use Google to search within Ansys Student Communityn