Incompressible NS solver with DG projection
******************* 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 everyone, I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification. All the best and thanks a lot! Alexander Sicher versendet mit [Proton Mail](https://proton.me/).
HI Alexander, Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this. Cheers, Spencer. From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection 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 everyone, I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification. All the best and thanks a lot! Alexander Sicher versendet mit Proton Mail<https://proton.me/>.
Hi both, Yes, Nektar++ so far does not have a readily available DG incNS solver. Theoretically, we can insert the AdvectionWeakDG class, and DisContField::v_HelmSolve() function into existing incNS framework to get a workable DG incNS sover. I tried it but the performance are not satisfying, especially compared with existing CG solver. So I didn't merge that code into master branch. In fact, I have been working on DG incompressible N-S solver for some time and a brand new version will come out soon. Many thanks, Boyang Xia ________________________________ From: Sherwin, Spencer J <s.sherwin@imperial.ac.uk> Sent: Sunday, March 24, 2024 16:29 To: Alexander Schukmann <alexander.schukmann@protonmail.com>; nektar-users <nektar-users@imperial.ac.uk>; Boyang Xia <boyang.xia@kcl.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection You don't often get email from s.sherwin@imperial.ac.uk. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> HI Alexander, Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this. Cheers, Spencer. From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection 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 everyone, I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification. All the best and thanks a lot! Alexander Sicher versendet mit Proton Mail<https://proton.me/>.
Hello Spencer and Boyang, thank you very much for your answers. @Boyang: will the new version of the ICNS solver come out with the next Nektar++ release, i.e. 5.6.0 or how will it be available? All the best, Alex Gesendet von Proton Mail für Mobilgeräte -------- Original-Nachricht -------- Am 24. März 2024, 21:40, schrieb Boyang Xia :
Hi both,
Yes, Nektar++ so far does not have a readily available DG incNS solver.
Theoretically, we can insert the AdvectionWeakDG class, and DisContField::v_HelmSolve() function into existing incNS framework to get a workable DG incNS sover. I tried it but the performance are not satisfying, especially compared with existing CG solver. So I didn't merge that code into master branch.
In fact, I have been working on DG incompressible N-S solver for some time and a brand new version will come out soon.
Many thanks, Boyang Xia
---------------------------------------------------------------
From: Sherwin, Spencer J <s.sherwin@imperial.ac.uk> Sent: Sunday, March 24, 2024 16:29 To: Alexander Schukmann <alexander.schukmann@protonmail.com>; nektar-users <nektar-users@imperial.ac.uk>; Boyang Xia <boyang.xia@kcl.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection
You don't often get email from s.sherwin@imperial.ac.uk. [Learn why this is important](https://aka.ms/LearnAboutSenderIdentification)
HI Alexander,
Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this.
Cheers,
Spencer.
From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection
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 everyone,
I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification.
All the best and thanks a lot!
Alexander
Sicher versendet mit [Proton Mail](https://proton.me/).
Hi Alexander, I still need another 2 or 3 months, to get the initial practical solver ready. To make it perfect takes more time. Best, Boyang Xia ________________________________ From: Alexander Schukmann <alexander.schukmann@protonmail.com> Sent: Sunday, March 24, 2024 21:54 To: Boyang Xia <boyang.xia@kcl.ac.uk>; s.sherwin@imperial.ac.uk <s.sherwin@imperial.ac.uk>; nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection You don't often get email from alexander.schukmann@protonmail.com. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> Hello Spencer and Boyang, thank you very much for your answers. @Boyang: will the new version of the ICNS solver come out with the next Nektar++ release, i.e. 5.6.0 or how will it be available? All the best, Alex Gesendet von Proton Mail für Mobilgeräte -------- Original-Nachricht -------- Am 24. März 2024, 21:40, schrieb Boyang Xia < boyang.xia@kcl.ac.uk>: Hi both, Yes, Nektar++ so far does not have a readily available DG incNS solver. Theoretically, we can insert the AdvectionWeakDG class, and DisContField::v_HelmSolve() function into existing incNS framework to get a workable DG incNS sover. I tried it but the performance are not satisfying, especially compared with existing CG solver. So I didn't merge that code into master branch. In fact, I have been working on DG incompressible N-S solver for some time and a brand new version will come out soon. Many thanks, Boyang Xia ________________________________ From: Sherwin, Spencer J <s.sherwin@imperial.ac.uk> Sent: Sunday, March 24, 2024 16:29 To: Alexander Schukmann <alexander.schukmann@protonmail.com>; nektar-users <nektar-users@imperial.ac.uk>; Boyang Xia <boyang.xia@kcl.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection You don't often get email from s.sherwin@imperial.ac.uk. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> HI Alexander, Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this. Cheers, Spencer. From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection 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 everyone, I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification. All the best and thanks a lot! Alexander Sicher versendet mit Proton Mail<https://proton.me/>.
Thanks again Boyang! As I'm working on the simulation of a free jet flow with preceding laminar-turbulent transition within the shear layer of a separation bubble inside a plane channel, would you recommend to use CG or CG-DG (i.e. mixed) implementation of the incompressible Navier-Stokes solver? Re is O(1e3) and Ma << 1. I read that DG projection is necessary if discontinuities are present within the flow field and/or material properties, but it also has other advantages over CG, such as: - can use exact integration - can be used efficiently with tetrahedra and hexahedra - easy to use P-adaptivity - positivity preserving numerical fluxes and limiters. But for CG it is easier to contruct IMEX formulations. So would it be more recommendable to rely on CG-DG instead of CG? Thank you for your time and patience. All the best,Alex Boyang Xia <boyang.xia@kcl.ac.uk> schrieb am Sonntag, 24. März 2024 um 23:01:
Hi Alexander,
I still need another 2 or 3 months, to get the initial practical solver ready. To make it perfect takes more time.
Best, Boyang Xia
---------------------------------------------------------------
From: Alexander Schukmann <alexander.schukmann@protonmail.com> Sent: Sunday, March 24, 2024 21:54 To: Boyang Xia <boyang.xia@kcl.ac.uk>; s.sherwin@imperial.ac.uk <s.sherwin@imperial.ac.uk>; nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection
You don't often get email from alexander.schukmann@protonmail.com. [Learn why this is important](https://aka.ms/LearnAboutSenderIdentification) Hello Spencer and Boyang,
thank you very much for your answers. @Boyang: will the new version of the ICNS solver come out with the next Nektar++ release, i.e. 5.6.0 or how will it be available?
All the best, Alex
Gesendet von Proton Mail für Mobilgeräte
-------- Original-Nachricht -------- Am 24. März 2024, 21:40, schrieb Boyang Xia < boyang.xia@kcl.ac.uk>:
Hi both,
Yes, Nektar++ so far does not have a readily available DG incNS solver.
Theoretically, we can insert the AdvectionWeakDG class, and DisContField::v_HelmSolve() function into existing incNS framework to get a workable DG incNS sover. I tried it but the performance are not satisfying, especially compared with existing CG solver. So I didn't merge that code into master branch.
In fact, I have been working on DG incompressible N-S solver for some time and a brand new version will come out soon.
Many thanks, Boyang Xia
---------------------------------------------------------------
From: Sherwin, Spencer J <s.sherwin@imperial.ac.uk> Sent: Sunday, March 24, 2024 16:29 To: Alexander Schukmann <alexander.schukmann@protonmail.com>; nektar-users <nektar-users@imperial.ac.uk>; Boyang Xia <boyang.xia@kcl.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection
You don't often get email from s.sherwin@imperial.ac.uk. [Learn why this is important](https://aka.ms/LearnAboutSenderIdentification)
HI Alexander,
Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this.
Cheers,
Spencer.
From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection
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 everyone,
I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification.
All the best and thanks a lot!
Alexander
Sicher versendet mit [Proton Mail](https://proton.me/).
Hi Alexander, Re is O(1e3) and Ma << 1 is neither high Re flow nor supersonic flow. A moderate fine mesh should achieve a smooth solution, so I think discontinuity is not a great concern in your case. Exact integration, tet and hex are also supported in Nektar++ CG. So basically I recommend you to use CG. Many Nektar++ users already investigate laminar-turbulent transition. You can read their papers or initiate another thread for help. Best, Boyang Xia ________________________________ From: Alexander Schukmann <alexander.schukmann@protonmail.com> Sent: Monday, March 25, 2024 9:41 To: Boyang Xia <boyang.xia@kcl.ac.uk> Cc: s.sherwin@imperial.ac.uk <s.sherwin@imperial.ac.uk>; nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection Thanks again Boyang! As I'm working on the simulation of a free jet flow with preceding laminar-turbulent transition within the shear layer of a separation bubble inside a plane channel, would you recommend to use CG or CG-DG (i.e. mixed) implementation of the incompressible Navier-Stokes solver? Re is O(1e3) and Ma << 1. I read that DG projection is necessary if discontinuities are present within the flow field and/or material properties, but it also has other advantages over CG, such as: * can use exact integration * can be used efficiently with tetrahedra and hexahedra * easy to use P-adaptivity * positivity preserving numerical fluxes and limiters. But for CG it is easier to contruct IMEX formulations. So would it be more recommendable to rely on CG-DG instead of CG? Thank you for your time and patience. All the best, Alex Boyang Xia <boyang.xia@kcl.ac.uk> schrieb am Sonntag, 24. März 2024 um 23:01: Hi Alexander, I still need another 2 or 3 months, to get the initial practical solver ready. To make it perfect takes more time. Best, Boyang Xia ________________________________ From: Alexander Schukmann <alexander.schukmann@protonmail.com> Sent: Sunday, March 24, 2024 21:54 To: Boyang Xia <boyang.xia@kcl.ac.uk>; s.sherwin@imperial.ac.uk <s.sherwin@imperial.ac.uk>; nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection You don't often get email from alexander.schukmann@protonmail.com. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> Hello Spencer and Boyang, thank you very much for your answers. @Boyang: will the new version of the ICNS solver come out with the next Nektar++ release, i.e. 5.6.0 or how will it be available? All the best, Alex Gesendet von Proton Mail für Mobilgeräte -------- Original-Nachricht -------- Am 24. März 2024, 21:40, schrieb Boyang Xia < boyang.xia@kcl.ac.uk>: Hi both, Yes, Nektar++ so far does not have a readily available DG incNS solver. Theoretically, we can insert the AdvectionWeakDG class, and DisContField::v_HelmSolve() function into existing incNS framework to get a workable DG incNS sover. I tried it but the performance are not satisfying, especially compared with existing CG solver. So I didn't merge that code into master branch. In fact, I have been working on DG incompressible N-S solver for some time and a brand new version will come out soon. Many thanks, Boyang Xia ________________________________ From: Sherwin, Spencer J <s.sherwin@imperial.ac.uk> Sent: Sunday, March 24, 2024 16:29 To: Alexander Schukmann <alexander.schukmann@protonmail.com>; nektar-users <nektar-users@imperial.ac.uk>; Boyang Xia <boyang.xia@kcl.ac.uk> Subject: Re: [Nektar-users] Incompressible NS solver with DG projection You don't often get email from s.sherwin@imperial.ac.uk. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> HI Alexander, Not sure if anyone has got back to you. I do not think we have a working DG inc Navier-Stokes yet since using DG does lead to a slightly different polynomial space. However I believe Boyang (cc’ed) has been looking into this. Cheers, Spencer. From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Alexander Schukmann <alexander.schukmann@protonmail.com> Date: Sunday, 17 March 2024 at 17:04 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Incompressible NS solver with DG projection 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 everyone, I have a quick question regarding the user guide entry for the ICNS solver. The table of possible values for the EqType tag under 11.3.2 in the 5.5.0 user guide does not list "DG" as a projection for the unsteady NS equations (only CG and CG-DG, i.e. mixed projection). However, under 11.3.3 under "Driver" it says DG for the Standard driver. I am a little bit confused as to whether the ICNS solver can be used with DG projection or not and would appreciate some clarification. All the best and thanks a lot! Alexander Sicher versendet mit Proton Mail<https://proton.me/>.
participants (3)
- 
                
                Alexander Schukmann
- 
                
                Boyang Xia
- 
                
                Sherwin, Spencer J