Research on roll stabilization for ships at anchor

Abstract

With the increasing importance of ocean exploitation, providing anti-rolling stability for ships at anchor has become more and more important. The lift-generation theory of traditional fin stabilizers is based on incoming flow velocity, which is not suitable for explaining lift generated at anchor. We analyzed non-steady flows, with forces on fin stabilizers generated by non-incoming flow velocity conditions, and gave a new lift-generation model. The correctness of the model was proven by comparing experimental results of fin stabilizer motion under non-incoming velocity conditions from the fluid computation software with that from the emulator of the lift-generation model. Finally, the model was used in an anti-rolling system on a ship and the reduction of roll was much better than what could be achieved by passive anti-rolling tanks.

Keywords

at anchor / anti-rolling / lift-generation model / fluent simulation

References

[1] Oms J. The use of roll stabiliser fins at zero speed[R]. 2002, Nuth, Holland: Quantum Controls BV, 1-5

[2] JIN Hongzhang, YU Wang, QI Zhigang, et al. Study on lift generation of Weis-fogh flapped fin stabilizer at zero speed[C]//SICE-ICASE International Joint Conference. Busan, 2006: 18–21.

[3] SOHN M H, CHANG J W. Flow visualization and aerodynamic load calculation of three types of clap-fling motions in a weis-Fogh mechanism[J]. Aerospace Science and Technology, 2006(10): 11–18.

[4] JIN Hongzhang, QI Zhigang, HE Jie. Research on a method to reduce ship roll at zero speed[C]//9th Int. Conf. Control, Automation, Robotics and Vision. Singapore, 2006:1812–1815.

[5] QI Z G, JIN H Z, YU W. Research on ship roll stabilization at zero speed[C]//SICE-ICASE International Joint Conference. Busan: 2006: 18–21.

[6] Jin H., Luo Y., Qi Z., et al. Investigation of the lifting force of a zero speed fin stabilizer with Weis-fogh mechanism[J]. Journal of Harbin Engineering University, 2007, 28(7): 398-402

[7] Yu L., Jin H., Wang H., et al. Research on simulation of an integrated stabilization system based on sway platform equipment[J]. Journal of Harbin Engineering University, 2007, 28(9): 1014-1019

[8] Yu L., Jin H., Wang H., et al. Research on the influence of action between fin and anti-rolling tank on the integrated stabilization effect[J]. Journal of marine Science and Application, 2007, 6(1): 9-14

[9] Jin H., Yao X. Ship control theory[M]. 2001, Harbin: Harbin Engineering University Press, 1-10

[10] Jin H., Li G. Control system of special equipments on ship[M]. 1995, Beijing: National Defence Industry Press, 100-110

[11] DALLINGA R P. Roll stabilisation at anchor: hydrodynamic aspects of the comparison of anti-roll tanks and fins[R]. Maritime Research Institute Netherlands, 2002:1–5.

[12] KLAKA K, KROKSTAD J, RENILSON M R. Prediction and measurement of the roll motion of a sailing yacht at zero forward speed[J]. Experimental Thermal and Fluid Science, 2003(27): 611–617.