[hungnguyen1908]

Hi all,
I was making a simulation of Vane Tidal Turbine. Meshing the model seems okay. Besides, in CFX-Pre, I set up the parameters following the ones I made for my simualation in Trasient. Of course it run very well. But when I change the parameters (used for Transient) into the ones in Steady state, and used outlet boundary condition for the outlet (in Trasient, I used "opening condition"), it always appeared immediately the error named "Overflow".
I'm really confused about this error, though I also reduced the timesteps from 1e^-4 to 1e^-5,..
Please help me to find out the reasons that caused this error.
Many thanks!

[rrr311]

Originally Posted by hungnguyen1908

Hi all,
I was making a simulation of Vane Tidal Turbine. Meshing the model seems okay. Besides, in CFX-Pre, I set up the parameters following the ones I made for my simualation in Trasient. Of course it run very well. But when I change the parameters (used for Transient) into the ones in Steady state, and used outlet boundary condition for the outlet (in Trasient, I used "opening condition"), it always appeared immediately the error named "Overflow".
I'm really confused about this error, though I also reduced the timesteps from 1e^-4 to 1e^-5,..
Please help me to find out the reasons that caused this error.
Many thanks!

I believe its too little too late. Anyways

Refer the link to check the possible reasons for your error.

http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F

Since you mention that you get the error upon changing from Opening to Outlet BC, extend the flow domain further downstream and use Outlet BC. You might want to look at the following link (particularly the last part of it).

https://www.sharcnet.ca/Software/Flu.../i5500692.html

Best,
Rahul