Hi, I am comparing the methods in the DGMulti Solver from Trixi with a visquous example but when I try to use the Finite difference methods periodic_derivative_operator(derivative_order=1, accuracy_order=4, xmin=0.0, xmax=1.0, N=50) and give it to the semidiscritisation i get this error at the beginning of the simulation :

I think the combination of FD operators amd viscous terms is iust not supported at the moment - since we don’t have such an example in Trixi.jl right now. Correct me if I’m wrong, @jlchan
That being said, we would be happy to help you to make a PR to fix this if you’re interested

Hi ! Thanks for the quick response-
Unfortunatly I am not totally confident in my capabilities on the subject. I am currently an aerospace engineering student working with your package for a project and I am not sure I have the right tools and knowledge to implement something.
I still have trouble with the Julia programming language and not totally familliar with Trixi.jl architecture.
I find it very interesting to work on but I may not be qualified enough…

@Kelian_Renoux - yes, @ranocha is correct - the FD operators are not yet supported. However, I’d be happy to help with implementation - I’ve implemented FD viscous terms in an experimental code before using upwind/downwind SBP operators.