The numerical study on active control strategies of T-foil

Abstract

ObjectivesAn active control T-foil can effectively improve the longitudinal anti-rolling motion of the ship, but there is still no conclusion on what control strategy has the best anti-rolling effect. So the paper has studied and analyzed the active control strategies of the T-foil.Methods The paper uses the slender body theory to calculate the longitudinal motion of Wigley III in regular waves of different wavelengths. Then, the damping effect of the ship with the passive and active T-foil is calculated and analyzed under the same speed and wave conditions. Results The results show that the passive control T-foil has a good anti-rolling effect in the resonance region, however, the anti-rolling effect in the long and short wave region is relatively limited. The control with a pitch velocity signal is very effective in reducing the pitch motion and the acceleration of bow motion, but it increases the heave motion in the longwave area. The anti-rolling effect of bow motion velocity signal on-pitch motion and acceleration of bow motion is 10%-20% higher than that of a pitch velocity signal, and there is no reduction effect on heave motion.Conclusions For the active control strategies of T-foil, the bow motion velocity signal can achieve a better anti-rolling effect by comprehensively considering both pitch and heave motions.

Keywords

• high speed ship
• t-foil
• active control
• control signal