May 2023 - Nektar-users - imperial.ac.uk

Re: [Nektar-users] use 2-d initial condition for quasi-3d simulation
by Ehsan Asgari 29 May '23

29 May '23

Hi Stanislaw I tried your suggestion but I get some error. Do you have any idea how I can fix this? Initial Conditions: > - Field u: from file inlflow2D_restart.fld > - Field v: from file inlflow2D_restart.fld > - Field w: 0.0 > - Field p: 0.0 > CFL (zero plane): 1.22293e-06 (in elmt 6555) > Fatal : Level 0 assertion violation > m_timestep < 0 > Fatal : Level 0 assertion violation > m_timestep < 0 > Fatal : Level 0 assertion violation > m_timestep < 0 > Fatal : Level 0 assertion violation > m_timestep < 0 > Fatal : Level 0 assertion violation Here is my initial condition: <FUNCTION NAME="InitialConditions"> > <F VAR="u,v" FILE="inflow2D_restart.fld" /> > <E VAR="w,p" VALUE="0.0" /> > </FUNCTION> Kind regards syavash On Fri, May 26, 2023 at 11:07 AM Stanisław Gepner < stanislaw.gepner(a)pw.edu.pl> wrote: > Hi, > > It is, all you need is an XML file for the aquasi-3D simulation with > velocity components u,v,w and pressure p, just as you would in quasi 3D, > than in initial conditions you do: > > <FUNCTION NAME="InitialConditions"> > <F VAR="u,v" FILE="geom2D.fld" /> > <E VAR="w" FILE="0" /> > <E VAR="p" VALUE="0" /> > </FUNCTION> > > You could also initialize w from file, eg. using solution from the ADR > solver or any other fld file. > > Cheers! > Stan > > > *Faculty of Power and Aeronautical Engineering* > Nowowiejska 21/25 Str. > 00-665 Warsaw, Poland > phone +48 (22) 234 51 70 > > <https://www.pw.edu.pl/engpw> > On 26.05.2023 08:30, Ehsan Asgari wrote: > > This email from eh.asgari(a)gmail.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. > > > Dear All, > > Is it possible to run a 2-d simulation and then use it solution for the > quasi-3d simulation of the same mesh? If so, how can I achieve this? > > Kind regards > syavash > > _______________________________________________ > Nektar-users mailing listNektar-users@imperial.ac.ukhttps://mailman.ic.ac.uk/mailman/listinfo/nektar-users > >

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Implementing rough wall condition
by Selman BAYSAL 29 May '23

29 May '23

******************* 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. ******************* Dear all,I am relatively new to CFD and Nektar++. Although there are much studies perfomed by Nektar++ on flows over rough surface/bed, I could not find detailed information on&nbsp;how to define a rough surface.I intended to define a rough surface/boundary (not a single roughness element or hump), and then, to investigate the boundary layer developed over this surface. For this purpose, do I need an external program like GMSH or is there any parameters (such as Nikuradse equivalent sand roughness or roughness height) or&nbsp;modules implemented in Nektar++? Any help would be greatly appreciated!Many thanks,Selman BaysalR. A. in HydraulicsDept. of Civil Eng'gÇanakkale Onsekiz Mart University--ITU Civil Eng., BSc.ITU Coastal Sci. &amp; Eng., MSc.

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Re: [Nektar-users] use 2-d initial condition for quasi-3d simulation
by Ehsan Asgari 26 May '23

26 May '23

Thank you. It is what I was looking for. syavash On Fri, May 26, 2023 at 11:07 AM Stanisław Gepner < stanislaw.gepner(a)pw.edu.pl> wrote: > Hi, > > It is, all you need is an XML file for the aquasi-3D simulation with > velocity components u,v,w and pressure p, just as you would in quasi 3D, > than in initial conditions you do: > > <FUNCTION NAME="InitialConditions"> > <F VAR="u,v" FILE="geom2D.fld" /> > <E VAR="w" FILE="0" /> > <E VAR="p" VALUE="0" /> > </FUNCTION> > > You could also initialize w from file, eg. using solution from the ADR > solver or any other fld file. > > Cheers! > Stan > > > *Faculty of Power and Aeronautical Engineering* > Nowowiejska 21/25 Str. > 00-665 Warsaw, Poland > phone +48 (22) 234 51 70 > > <https://www.pw.edu.pl/engpw> > On 26.05.2023 08:30, Ehsan Asgari wrote: > > This email from eh.asgari(a)gmail.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. > > > Dear All, > > Is it possible to run a 2-d simulation and then use it solution for the > quasi-3d simulation of the same mesh? If so, how can I achieve this? > > Kind regards > syavash > > _______________________________________________ > Nektar-users mailing listNektar-users@imperial.ac.ukhttps://mailman.ic.ac.uk/mailman/listinfo/nektar-users > >

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use 2-d initial condition for quasi-3d simulation
by Ehsan Asgari 26 May '23

26 May '23

******************* 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. ******************* Dear All, Is it possible to run a 2-d simulation and then use it solution for the quasi-3d simulation of the same mesh? If so, how can I achieve this? Kind regards syavash

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Flowrate Enforcement Question
by Ma, Ting-Hsuan 16 May '23

16 May '23

******************* 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. ******************* Hi, This may be a dumb question, but when we are setting a flowrate for a 3D1H problem (flow in the x-y and homogenous expansion in the Z). How would I set my Kinvis such that it follows the Reynolds number I am targeting? Within the parameters, enables the tag "Flowrate = 1.0". If I am doing a homogenous expansion in the z-direction, would I need to take into account LZ? or is this done automatically through the code? I am getting confused by the notations that is used within the user manual, and looking within the source code does not help me too much as both versions do not explicitly state to take into account the area of just the line. Any insight is appreciated, Dustin

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potential bug with detailed expansion
by Ehsan Asgari 15 May '23

15 May '23

******************* 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. ******************* Dear All, When I use a "Modfied" type for expansions everything works fine. But if I specify the expansions in detailed mode: <E COMPOSITE="C[30011]" > BASISTYPE="Modified_A,Modified_A,Modified_A" > NUMMODES="7,7,7" > POINTSTYPE="GaussLobattoLegendre,GaussLobattoLegendre,GaussRadauMAlpha1Beta0" > NUMPOINTS="8,8,7" > FIELDS="u,v,w" /> > <E COMPOSITE="C[30011]" > BASISTYPE="Modified_A,Modified_A,Modified_A" > NUMMODES="6,6,6" > > POINTSTYPE="GaussLobattoLegendre,GaussLobattoLegendre,GaussRadauMAlpha1Beta0" > NUMPOINTS="7,7,6" > FIELDS="p" /> Then I get a bunch of errors: [xxx518:29773] *** Process received signal *** > [xxx518:29773] Signal: Segmentation fault (11) > [xxx518:29773] Signal code: Address not mapped (1) > [xxx518:29773] Failing at address: 0x27b2000 I have a fully hex mesh. Could you kindly point out if something is wrong with the way I specify the expansions? Kind regards syavash

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Help
by Flávio Valberto Barrionuevo Rodrigues 15 May '23

15 May '23

******************* 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 dear Nektar users. I am trying to import mesh from Gmesh and run a code function called SteadyAdvectionDiffusionReaction. But I have a "segmentation fault" every time. If someone could help with this, I would be grateful.

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Reducing File Count of .fld Outputs in-situ
by Isaac Rosin 14 May '23

14 May '23

******************* 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. ******************* Dear Nektar++, I am using the FieldConvert filter in my session file to output vorticity. I then isolate regions of my domain using the range option (-r) of FieldConvert in post-processing. To enable the isolation of these regions, I have found that I should produce .fld files with my filter as opposed to .plt, .dat, etc. Here is my filter: <FILTER TYPE="FieldConvert"> <PARAM NAME="OutputFile">Fields.vtu</PARAM> <PARAM NAME="OutputFrequency">1</PARAM> <PARAM NAME="Modules">vorticity</PARAM> </FILTER> When running in parallel, this filter will output .fld directories with .fld files in them each corresponding to the processors used. This is where the issue arises: I am running simulations on a cluster using many processors and I need to save lots of time steps. My cluster has a 1 million file limit, and I will quickly hit this if I do not convert and overwrite the .fld directories into single .fld files in-situ. I know the command to do this in post-processing: FieldConvert -f session.xml Fields_#_fc.fld/ Fields_#_fc.fld but so far, have not been successful in implementing this in-situ. I would be very grateful if you could offer a solution or at least steer me in the right direction with this issue. Thank you very much in advance, and I look forward to hearing from you. Sincerely, Isaac

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Face Orientation and Mailing List
by Isaac Rosin 13 May '23

13 May '23

******************* 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 Nektar++, 1. I am trying to run a 3D simulation on a simple geometry using IncNavierStokesSolver with all orthogonal cells and two sets of periodic boundary conditions, but I keep getting this message: Fatal : Level 0 assertion violation unable to determine face orientation I tried using the peralign module with and without the orient parameter with no success. I also went into gmsh and made sure all of the mesh surface normal vectors were pointing inwards but encountered the same error. I have attached my session and geometry files to the bottom of this email as OneDrive links. 2. Is there an issue with the subscription to the Nektar users mailing list? I requested to join Nektar-users around the beginning of May but still have not received the confirmation email. Regards, Isaac [https://res-h3.public.cdn.office.net/assets/mail/file-icon/png/code_16x16.p…<https://uofc-my.sharepoint.com/:u:/g/personal/isaac_rosin1_ucalgary_ca/Eb-t…> [https://res-h3.public.cdn.office.net/assets/mail/file-icon/png/code_16x16.p…<https://uofc-my.sharepoint.com/:u:/g/personal/isaac_rosin1_ucalgary_ca/EX2V…> [https://res.cdn.office.net/assets/mail/file-icon/png/generic_16x16.png]geom…<https://uofc-my.sharepoint.com/:u:/g/personal/isaac_rosin1_ucalgary_ca/Edo3…>

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Nektar++ workshop 2023: registration now open
by Moxey, David 10 May '23

10 May '23

Dear all, This is a quick announcement to say that registration for the Nektar++ workshop is now open. You can register directly here: https://cassyni.com/s/nektar-workshop-2023 A few notes: - More details regarding the workshop are now online here: https://www.nektar.info/community/workshops/nektar-workshop-2023/ - We plan to hold the workshop as a hybrid event, although we encourage in-person attendance if possible! - If you would like to give a talk and/or present a poster, please tick the appropriate box/boxes on the registration page, and send me an email with a title/short abstract. - We encourage those who wish to present to let us know by Monday 22nd May so that we can finalise the schedule. If you have any questions, please do let me know! Many thanks, Dave -- Dr David Moxey, PhD MMath FHEA Reader in Engineering david.moxey(a)kcl.ac.uk | web: davidmoxey.uk Department of Engineering, King's College London, Strand, London, WC2R 2LS.

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