******************* This email 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. ******************* Hello, I am using CoupledLinearisedNS solver for 2D stabiblty analysis. To do this, it is needed to set the imaginary eigenvalue shift. Now it is possible only in 3D with a homogeneous direction. I set an appropriate 3D case and the BetaZero property that overrides LHom. As a result, eigenvalues look nice, but eigenfunctions are not. The eigenfunctions are not two-dimensional. How I can get the eigenfunctions? Or my proposition about the BetaZero property is wrong? Alex Proskurin Altai state technical university
Hi Alex, I am sorry I have not looked at this in quite a while. Have you looked at the tests in Nektar/solvers/IncNavierStokesSolvers/Tests since I wonder if there is an example in this directory which could be helpful. Cheers, Spencer. On 24 Aug 2022, at 13:44, A.P. <k210@list.ru<mailto:k210@list.ru>> wrote: This email from k210@list.ru<mailto:k210@list.ru> 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. Hello, I am using CoupledLinearisedNS solver for 2D stabiblty analysis. To do this, it is needed to set the imaginary eigenvalue shift. Now it is possible only in 3D with a homogeneous direction. I set an appropriate 3D case and the BetaZero property that overrides LHom. As a result, eigenvalues look nice, but eigenfunctions are not. The eigenfunctions are not two-dimensional. How I can get the eigenfunctions? Or my proposition about the BetaZero property is wrong? Alex Proskurin Altai state technical university <HatrmannEigenfunc.jpg>_______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
Thank you, Spencer. The tests output eigenfunctions are 3D. I guess that 2D eigenfuntions can be obtained by FieldConvert -m homplane:planeid=0 (or 1)… but it is unknown how to interpret w component of velocity. Alex.
Воскресенье, 4 сентября 2022, 22:08 +07:00 от "Sherwin, Spencer J" <s.sherwin@imperial.ac.uk>: Hi Alex, I am sorry I have not looked at this in quite a while. Have you looked at the tests in Nektar/solvers/IncNavierStokesSolvers/Tests since I wonder if there is an example in this directory which could be helpful. Cheers, Spencer.
On 24 Aug 2022, at 13:44, A.P. < k210@list.ru > wrote: This email from k210@list.ru 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 to disable email stamping for this address. Hello, I am using CoupledLinearisedNS solver for 2D stabiblty analysis. To do this, it is needed to set the imaginary eigenvalue shift. Now it is possible only in 3D with a homogeneous direction. I set an appropriate 3D case and the BetaZero property that overrides LHom. As a result, eigenvalues look nice, but eigenfunctions are not. The eigenfunctions are not two-dimensional. How I can get the eigenfunctions? Or my proposition about the BetaZero property is wrong? Alex Proskurin Altai state technical university <HatrmannEigenfunc.jpg> _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
Hi Alex, I believe that planeid=0 would return the contact mode but planeid=1 would be the imaginary mode which potentially should be zero. So I think the only physical interpretation would be a mode that is constantly in the z-direction and so Lz tends to infinity which gives beta that is zero. There is a half mode interpretation for this stability code 2 although I do not recall if I implemented this in the coupled solver. A half mode is one where you can use the symmetry that u,v,w scales like cos(beta z), cos (beta z), sin(beta z) which is only possible fi the base flow is orthogonal to the instability direction. However possibly you are not using this option. Cheers, Spencer. On 5 Sep 2022, at 17:57, A.P. <k210@list.ru<mailto:k210@list.ru>> wrote: Thank you, Spencer. The tests output eigenfunctions are 3D. I guess that 2D eigenfuntions can be obtained by FieldConvert -m homplane:planeid=0 (or 1)… but it is unknown how to interpret w component of velocity. Alex. Воскресенье, 4 сентября 2022, 22:08 +07:00 от "Sherwin, Spencer J" <s.sherwin@imperial.ac.uk<mailto:s.sherwin@imperial.ac.uk>>: Hi Alex, I am sorry I have not looked at this in quite a while. Have you looked at the tests in Nektar/solvers/IncNavierStokesSolvers/Tests since I wonder if there is an example in this directory which could be helpful. Cheers, Spencer. On 24 Aug 2022, at 13:44, A.P. <k210@list.ru<x-msg://e.mail.ru/compose/?mailto=mailto%3ak210@list.ru>> wrote: This email from k210@list.ru<x-msg://e.mail.ru/compose/?mailto=mailto%3ak210@list.ru> 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. Hello, I am using CoupledLinearisedNS solver for 2D stabiblty analysis. To do this, it is needed to set the imaginary eigenvalue shift. Now it is possible only in 3D with a homogeneous direction. I set an appropriate 3D case and the BetaZero property that overrides LHom. As a result, eigenvalues look nice, but eigenfunctions are not. The eigenfunctions are not two-dimensional. How I can get the eigenfunctions? Or my proposition about the BetaZero property is wrong? Alex Proskurin Altai state technical university <HatrmannEigenfunc.jpg>_______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<x-msg://e.mail.ru/compose/?mailto=mailto%3aNektar%2dusers@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
participants (2)
-
A.P.
-
Sherwin, Spencer J