Dear NGsolve community,
I will to solve time dependent Navier-Stokes equations with divergence-free DG combined with IMEX scheme, where trilinear term is treated fully explicit. The following is the code for the trilinear term with unwinding flux:
conv = BilinearForm(fes, nonassemble = True)
conv += InnerProduct(Grad(u) * u, v)* dx
un = InnerProduct(u,n)
vup = IfPos(un, tang(v.Other()), tang(v))
dskel_inner = dx(skeleton=True)
dskel_bound = ds(skeleton=True)
conv += (un*(tang(u.Other())-tang(u))* vup) * dskel_inner #interior edge
Here tang represents the tangential component. The solution seems incorrect with the above (if I just delete the edge term, it is working well). May I ask if there is any error for the edge term? Thank you very much
Best regards,
Lina