Anti Roll Tanks

Hello dear community,

I have a question about how to create an elevated anti-scratch tank in Maxsurf Stability Advanced, first to verify its free surface effect, the tank is located on the bow castle deck, the software does not recognize the total dimension of the tank, apparently it is out of your domain, how can I solve this?

Secondly, in Maxsurf Motions Advanced, I don't see any option to include anti-roll tanks, to calculate the new roll response.

Thank you,

I await your prompt reply.

ATTE.Heinz Bill Galdós Lindao

  • Hi Heinz,

    All Tanks and compartments must be inside the hull. So if you are trying to model a deck tank that sits above the deck, you will need to add surfaces in Modeler to create the additional space of the tank, and then put a tank inside it.

    To accurately account for the movement of fluids in a static scenario, ensure that you are simulating the fluid movement in Analysis | Fluids.

    Regarding anti-roll tanks in motions; Motions is a single, rigid body solver. You won't be able to model the shift in CoG or movement of tank fluids independent of the vessel body. I would analyse the non-damped vessel in motions to determine the required tuning frequency and damping.

    If your vessel is ship shaped, you can use strip theory to conduct a static roll decay test to identify the natural period of roll (Analysis | Calculate Wave surface, Static Free Surface, followed by Display | Animate and save the time history data. You can also determine the required damping for critical damping so you can create and tune your anti-roll tank.

    Regards,

    James

    Answer Verified By: James Clarkson