Timestep in Free Surface Wigley Hull

Carlos Andrés

I have spent about two months trying to simulate a half wigley hull in a domain with 10m long x 2.25m width x 3m high with a half hull in a symmetry plane, 2 m from the inlet + 1m hull + 7m to the outlet = 10m long. The aspect ratio of the mesh is between 1.25 and 20. Determinant 3x3x3 is over 0.95. B.C. at inlet is normal velocity and Outlet is Static Pressure.

In the solver control when I select Upwind at Advection Scheme the simulation always crashes in less than 10 iterations with the message error "Floating point exception: Overflow"

It doesn't matter if I set a less Physical timescale for Volume Fraction. Any combination of timesteps end up crashing. Even following the CFX manual recommendations for timestep values as a fraction of the particle residence.

When I select High resolution at Advection Scheme and Physical timestep I obtain oscillatory results in RMS quantities.

Although, local timestep factor seems run the final solutions is far away of the expected results.

How could I figure out this parameters in the Solver Control in order to obtain a solution.

Thanks in advance,

Carlos Andrés.