What does 20 in convectParallel(Mesh, [u1, u2], -dt, c, 20) mean

Does anyone know what 20 denotes in command convectParallel(Mesh, [u1, u2], -dt, c, 20) ?

It is a safety parameter.

Many thanks. So I will keep it in case this command won’t work.

Sorry, I want to ask a further question, if I want to change this parameter, if it is more better if I make it larger or smaller?

It’s problem dependent. In general, you should not use this function.

Thank you very much for your reply. I think it’s unreliable to use convect command to parallelize NS equation. So I will transfer to use Newton method.