Discontinuity of velocity between rotating and stationary domains

- October 13, 2023 at 8:12 am
  
  Rou Yi Lim
  Subscriber
  
  Hi, I am trying to simulate a hydro turbine in a water flow using Fluent. I followed some tutorials online and made two domains: rotating (with boolean turbine) and stationary domain. The rotating domain has 'Frame Motion', and the walls are 'stationary wall' with 'relative motion to adjacent cell zone'. The inlet is velocity inlet with 2.5m/s water flow and outlet is pressure outlet with gauge pressure set to 0Pa.
  When I ran the simulation, I got this contour that shows discontinuity of velocity between stationary and rotating domain. The velocity streamlines also stop when it touches the turbine, which I suspect is due to the discontinuity. Can anyone help me with this problem?
  I attach some photos to hopefully help you understand what I describe. Thank you.
- October 18, 2023 at 11:23 am
  
  C N
  Ansys Employee
  
  Hello Rou,
  If you do not set the appropriate interface and boundary conditions there can be the discontinuity of velocity between rotating and stationary domains.
  I recommend you to use the turbo workflow feature for your turbomachinery simulation which is very easy to set up and there will no issues with discontinuity of velcoity between rotating and stationary domains.
  I am attaching the how to do video and user guide link of a sample tutorial which would be helpful for your simulation change the machine to turbine instead of compressor and follow the best practices mentioned in the video to model your simulation.
  Chapter 11: Turbomachinery Setup and Analysis Using the Turbo Workflow (ansys.com)
  (1033) Using the Ansys Fluent Turbo Workflow - YouTube
  I hope this helps you in your simulation.
  Thanks,