Hello there, I am trying to implement a time-dependent incompressible Navier-Stokes flow, and it ‘sorta works’, but it gets unstable at the outlet when the velocity gets high. I have tried to run the code on a finer mesh and with smaller time steps, but that does not change anything about the inst…

Mixed incompressible Navier-Stokes

dokken November 16, 2020, 1:53pm 2

I would suggest starting with verifying your solver using the Taylor-Green vortex problem or the DFG-2D benchmark, which are both covered in: Boundary Conditions & Convergence for 3D Navier-Stokes

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