Hi Both, Jeremy is right. I think we did have an option for nummodes=1 for the compressible code but have not checked if that works recently. Cheers, Spencer Sent from my iPhone On 7 Oct 2022, at 20:49, Kumar, Varun <varun_kumar2@brown.edu> wrote: Thanks, Jeremy. I read the details in the document and agree with your assessment. -- Regards Varun On Fri, Oct 7, 2022 at 2:31 PM Jeremy Cohen <jeremy.cohen@imperial.ac.uk<mailto:jeremy.cohen@imperial.ac.uk>> wrote: Hi Varun, I think that NUMMODES should actually be set to order+1, so to run your simulation at order 1, you need to set NUMMODES=2. This seems to be confirmed by the final paragraph of the pre-processing section of the advection-diffusion tutorial<https://doc.nektar.info/tutorials/latest/basics/advection-diffusion/basics-advection-diffusionch2.html#x3-50002> (take a look at the very end of that page where it shows the set up of the expansions). I note that in the files you’ve provided, you have NUMMODES=1. I tested running with your configuration and can reproduce the problem - the simulation crashes when NUMMODES=1 and runs when it’s set to 2. I may be wrong here so maybe someone else with more experience of setting up simulations can correct me if that’s the case but I suspect this could be the cause of the problem you’re seeing. If that’s true, we should add some error checking that prints an error or warning message when NUMMODES=1. Kind regards, Jeremy On 7 Oct 2022, at 19:01, Kumar, Varun <varun_kumar2@brown.edu<mailto:varun_kumar2@brown.edu>> wrote: This email from varun_kumar2@brown.edu<mailto:varun_kumar2@brown.edu> 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 comparing the simulation results for different Polynomial orders for compressible flow over a NACA airfoil. However, it appears that for order=1, the simulation crashes immediately with the error log attached here. I also attach the mesh and sessions file in the ZIP folder for reference. Any insights into this would be greatly appreciated. -- Varun Kumar Doctoral candidate (Engineering) 170 Hope St Brown University <CFS_NACA.zip>_______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk https://mailman.ic.ac.uk/mailman/listinfo/nektar-users