Issue with mixed form NavierStokes initialising


I have tried to run the cylinder_2d example with the only change being mixed_form=True in the NavierStokes initialiser.

ns = NavierStokes(nu=nd.ndim(nu), rho=nd.ndim(rho), dim=2, time=False, mixed_form=True)

However this doesn’t appear to initialise with it taking hours to start and it ran out of system memory crashing. As far as I can tell it is the PointwiseInteriorConstraint that is taking so long to setup.

Are there any tricks to getting NavierStokes to work with mixed_form? I have ~64Gb of system memory available, is it expect that using NavierStokes in this form would require more than this?

Best Regards


Hi @LimitingFactor

We have an example of mixed-form Navier-Stokes that you could use a reference. Does it hang on the definition of the N-S node, is it hanging when its generating points for a constraint, or else where?