[gradylemoine]

Hi all,

I'm attempting to model a wave tank with a sloped bottom using interFoam, and am running into trouble. Specifically, I seem to have some kind of numerical instability -- the time step gets reduced to a tiny value, and the continuity errors go up and up from one step to the next, until eventually NaNs start getting created and the whole simulation crashes.

I suspect that I have my boundary conditions wrong, but I'm not really sure. For pressure, I'm using buoyantPressure conditions for the bottom and sides of the tank, and a totalPressure condition at the top (value and p0 set to zero). Velocity is set to a fixedValue of (0 0 0) at the walls and floor, and a pressureInletOutletVelocity condition at the top of the tank.

Does anybody have any idea what's up here? The simulation works fine if I use a flat bottom, so I think it's probably the presence of a sloped bottom that's giving the trouble. I'm using a plain blockMesh setup, so the free surface won't align with the grid; on the other hand, that doesn't seem to be a problem on the faces of waves in a flat-bottomed tank. Any advice would be welcome.

Regards,

--Grady Lemoine