Dear Zenhua, Sorry I have not been able to keep up to date with emails this past months. Did you find a solution to your problem. If you are running the incompressible solver you might consider the HOUTFLOW conditions discussed in the user-guide? Cheers, Spencer. Spencer Sherwin FREng, FRAeS Head of Aerodynamics Section, Director of Research Computing Service, Professor of Computational Fluid Mechanics, Department of Aeronautics, s.sherwin@imperial.ac.uk<mailto:s.sherwin@imperial.ac.uk> South Kensington Campus, Phone: +44 (0)20 7594 5052 Imperial College London, Fax: +44 (0)20 7594 1974 London, SW7 2AZ, UK http://www.imperial.ac.uk/people/s.sherwin/ On 28 May 2020, at 04:05, 岳泽华 <yuezehua@buaa.edu.cn<mailto:yuezehua@buaa.edu.cn>> wrote: This email from yuezehua@buaa.edu.cn<mailto:yuezehua@buaa.edu.cn> originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list<https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email stamping for this address. Hi all, I'm working on a stability and dynamics analysis of a high Re folw past a slender blunt-based axisymmetric body by the IncNavierStokesSolver, then I need to set an angle of attack for the flow. So I set the inflow surface boundary condition by defining its velocity component, and it works well. My question is about the corresponding outflow boundary conditions, if i remain it as the 0-AOA conditions, the streamlines near the outlet surface will become wrong curves. And I tried several definitions of the outflow surface but it always failed. So I'm wondering how to write the outflow boundary conditions with an AOA, I'm really confused。 Thanks for your kind attention and help. Many thanks, Zehua Yue Beihang University _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users