PowerKernel for not available along homogeneous directions?
******************* 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 everybody, I am currently running Quasi-3D CG-SVV iLES with the IncNavierStokesSolver and noticed that the SVV PowerKernel is not activated/available for Fourier discretizations along homogeneous directions. However in the paper "Industry-relevant ILES of a high-performance road car via S/HPEM" (Mengaldo et al. 2021) it says: "The current best practice in Nektar has been to use the "DG" kernel in general while employin the "power-law" kenel only along homogeneous directions in case periodic boundary conditions are present" So does this mean the PowerKernel is only available if S/HP is also used along homogeneous directions? Why not use the DGKernel then? And how does one setup different SVV kernels for different spatial directions? If it DOES refer to the quasi-3D case, however, there seems to be an issue, since no output is given regarding SVV, if the "SpectralVanishingViscosityHomo1D" flag is set to "PowerKernel" within the session file. Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it works. All the best Alex Sicher versendet mit [Proton Mail](https://proton.me/).
Hi Alexander, SVV was originally defined for special methods similar to the homogeneous expansions. The SH/PEM use of SVV came later and it is for these expansions we have developed the different kernels. Spencer Sent from my iPhone On 12 May 2024, at 00:10, Alexander Schukmann <alexander.schukmann@protonmail.com> wrote: This email from alexander.schukmann@protonmail.com 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 everybody, I am currently running Quasi-3D CG-SVV iLES with the IncNavierStokesSolver and noticed that the SVV PowerKernel is not activated/available for Fourier discretizations along homogeneous directions. However in the paper "Industry-relevant ILES of a high-performance road car via S/HPEM" (Mengaldo et al. 2021) it says: "The current best practice in Nektar has been to use the "DG" kernel in general while employin the "power-law" kenel only along homogeneous directions in case periodic boundary conditions are present" So does this mean the PowerKernel is only available if S/HP is also used along homogeneous directions? Why not use the DGKernel then? And how does one setup different SVV kernels for different spatial directions? If it DOES refer to the quasi-3D case, however, there seems to be an issue, since no output is given regarding SVV, if the "SpectralVanishingViscosityHomo1D" flag is set to "PowerKernel" within the session file. Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it works. All the best Alex Sicher versendet mit Proton Mail<https://proton.me/>. _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
Hello Spencer, thank you for your response. I was just a littlw confused, because in the paper it says best practice for homogeneous directions is to use the PowerKernel and otherwise the DGKernel. So along Homo1D directions in Quasi-3D simulations, only the exponential Kernel is available? All the best Alex Gesendet von Proton Mail für Mobilgeräte -------- Original-Nachricht -------- Am 12. Mai 2024, 10:10, schrieb Sherwin, Spencer J :
Hi Alexander,
SVV was originally defined for special methods similar to the homogeneous expansions. The SH/PEM use of SVV came later and it is for these expansions we have developed the different kernels.
Spencer
Sent from my iPhone
On 12 May 2024, at 00:10, Alexander Schukmann <alexander.schukmann@protonmail.com> wrote:
This email from alexander.schukmann@protonmail.com 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 everybody,
I am currently running Quasi-3D CG-SVV iLES with the IncNavierStokesSolver and noticed that the SVV PowerKernel is not activated/available for Fourier discretizations along homogeneous directions. However in the paper "Industry-relevant ILES of a high-performance road car via S/HPEM" (Mengaldo et al. 2021) it says:
"The current best practice in Nektar has been to use the "DG" kernel in general while employin the "power-law" kenel only along homogeneous directions in case periodic boundary conditions are present"
So does this mean the PowerKernel is only available if S/HP is also used along homogeneous directions? Why not use the DGKernel then? And how does one setup different SVV kernels for different spatial directions? If it DOES refer to the quasi-3D case, however, there seems to be an issue, since no output is given regarding SVV, if the "SpectralVanishingViscosityHomo1D" flag is set to "PowerKernel" within the session file.
Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it works.
All the best Alex
Sicher versendet mit [Proton Mail](https://proton.me/). _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
That is what I believe. Unless anyone has added that option but I do not think so. Best, Spencer Sent from my iPhone On 12 May 2024, at 09:25, Alexander Schukmann <alexander.schukmann@protonmail.com> wrote: Hello Spencer, thank you for your response. I was just a littlw confused, because in the paper it says best practice for homogeneous directions is to use the PowerKernel and otherwise the DGKernel. So along Homo1D directions in Quasi-3D simulations, only the exponential Kernel is available? All the best Alex Gesendet von Proton Mail für Mobilgeräte -------- Original-Nachricht -------- Am 12. Mai 2024, 10:10, schrieb Sherwin, Spencer J < s.sherwin@imperial.ac.uk>: Hi Alexander, SVV was originally defined for special methods similar to the homogeneous expansions. The SH/PEM use of SVV came later and it is for these expansions we have developed the different kernels. Spencer Sent from my iPhone On 12 May 2024, at 00:10, Alexander Schukmann <alexander.schukmann@protonmail.com> wrote: This email from alexander.schukmann@protonmail.com 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 everybody, I am currently running Quasi-3D CG-SVV iLES with the IncNavierStokesSolver and noticed that the SVV PowerKernel is not activated/available for Fourier discretizations along homogeneous directions. However in the paper "Industry-relevant ILES of a high-performance road car via S/HPEM" (Mengaldo et al. 2021) it says: "The current best practice in Nektar has been to use the "DG" kernel in general while employin the "power-law" kenel only along homogeneous directions in case periodic boundary conditions are present" So does this mean the PowerKernel is only available if S/HP is also used along homogeneous directions? Why not use the DGKernel then? And how does one setup different SVV kernels for different spatial directions? If it DOES refer to the quasi-3D case, however, there seems to be an issue, since no output is given regarding SVV, if the "SpectralVanishingViscosityHomo1D" flag is set to "PowerKernel" within the session file. Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it works. All the best Alex Sicher versendet mit Proton Mail<https://proton.me/>. _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
******************* 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. ******************* Okay, I understand. Thanks for your time, really appreciate it. Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it is possible. Is there a specific reason for this? All the best Alex Alexander Schukmann <alexander.schukmann@protonmail.com> schrieb am Sonntag, 12. Mai 2024 um 1:10 vorm.:
Hello everybody,
I am currently running Quasi-3D CG-SVV iLES with the IncNavierStokesSolver and noticed that the SVV PowerKernel is not activated/available for Fourier discretizations along homogeneous directions. However in the paper "Industry-relevant ILES of a high-performance road car via S/HPEM" (Mengaldo et al. 2021) it says:
"The current best practice in Nektar has been to use the "DG" kernel in general while employin the "power-law" kenel only along homogeneous directions in case periodic boundary conditions are present"
So does this mean the PowerKernel is only available if S/HP is also used along homogeneous directions? Why not use the DGKernel then? And how does one setup different SVV kernels for different spatial directions? If it DOES refer to the quasi-3D case, however, there seems to be an issue, since no output is given regarding SVV, if the "SpectralVanishingViscosityHomo1D" flag is set to "PowerKernel" within the session file.
Also I noticed that it seems to be impossible to activate SVV only for the S/HP discretizations in quasi-3D cases, i.e. without using SVV for the Homo1D directions, but vice versa it works.
All the best Alex
Sicher versendet mit [Proton Mail](https://proton.me/).
participants (2)
-
Alexander Schukmann
-
Sherwin, Spencer J