I am trying to get the roll moment of a 2D U-shaped tank in forced oscillating motion. The tank is partially filled with water.
Since the computeforces tool does not provide such a quantity I am trying a different approach.
I measure pressures on several probes over the tank boundaries (I took the sloshing simulation as a reference starting point). The idea would be to compute the transverse and vertical forces from the pressure distribution. To compare these forces (e.g. the phase averaged time histories) with those resulting from te compute forces. To eventually scale the forces from pressures by the founded ratio. To compute the force moment (force x arm) by using the corrected pressures.
This reasoning would imply to get an almost correct pressure distribution at least in terms of 'shape' since the absolute value would then be corrected.
However I get very fluctuating pressures that lead to un useful results.
I have also checked the pressure distribution with the steady tank (no motion at all). At the very first time step the distribution seems correct and the described process results in the correct hydrostatic force. Unfortunately, from the second time step even those pressures on the steady tank have fluctuations that do not converge anywhere.
is there a chance to get rid in some ways of those fluctuations (I read in other discussions this is related to the boundary condition. BTW I am using delta-sph=0.1)?
has someone another idea to compute the force moment I am looking for?
Thanks a lot