Analysis of warship roll stabilisation by controlled anti-roll tanks with the aid of digital simulation

A dynamic model of the rolling motion of a ship incorporating roll stabilisation by means of anti-roll tanks is presented. Simulation results for typical applications give an indication of the possible improvement in roll stabilisation which could be achieved by the application of active controlled anti-roll tanks. During the investigation, the sensitivity of ship´s roll motion and anti-roll tank controller design to the ship´s metacentric height was highlighted. Although in general for warships this value remains sensibly constant the actual value is important. For the particular application to ships carrying aircraft the metacentric height changes significantly during docking down operations and ideally the control law should be able to adapt to such changes. Further studies involve the selection of suitable control valves and blower for the active control scheme and an analysis of their contribution to the stabilisation effect