Hi Ed, Sorry for the delayed response. Could you try removing EVAR="u v T p x y" from the forcing function only for T, for instance. <E VAR="u" VALUE="Gr*T" EVARS="u v T p" /> <E VAR="v" VALUE="0" EVARS="u v T p" /> <E VAR="T" VALUE="(1e10)*exp(-((x+0.25)^2+y^2)/(0.05^2))"/> The reason is because whenever EVAR (equation variables) is explicitly labelled, the forcing function look up the equation variables (u v T p) for the forcing values but not the space/time variables (x y t). Hope this helps! Cheers, Chi Hin ________________________________ From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Edward Threlfall <ejthrelfall@gmail.com> Sent: 18 January 2023 16:35 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Help with spatially-varying sourcing function. This email from ejthrelfall@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 community, I've set up a convection problem in the incompressible Navier-Stokes solver. I have an equation for the time-evolution of the temperature to which I would like to add a right-hand-side describing sources of local heating. Can I do this in Nektar++? I have tried implementing it via the bodyforce, however this seems to apply a spatially-uniform source and I want something like the Gaussian profile below. I am trying: <FUNCTION NAME="BodyForce"> <E VAR="u" VALUE="Gr*T" EVARS="u v T p" /> <E VAR="v" VALUE="0" EVARS="u v T p" /> <E VAR="T" VALUE="(1e10)*exp(-((x+0.25)^2+y^2)/(0.05^2))" EVARS="u v T p x y" /> </FUNCTION> then <FORCING> <FORCE TYPE="Body"> <BODYFORCE> BodyForce </BODYFORCE> </FORCE> </FORCING> Can anyone help, please? Thanks! Ed.