ROLL DAMPING OF A SHARP-CORNERED BARGE AND ROLL CONTROL BY A NEW-TYPE STABILIZER

Abstract

In the first part of the paper, prediction methods of the roll damping of a ship proposed by one of the authors are experimentally examined to confirm their applicability to a barge. Measurements of the roll damping of sharp-cornered barge-type ships are carried out by free decay tests and a forced roll test. The experimental results are compared with results obtained by the prediction methods. The comparisons demonstrate that the prediction method is valid only when the roll amplitude is smaller than five degrees and that at large roll amplitude the methods give overestimated results. In the second part of the paper, the effect of a new anti-rolling device using vertically oscillating fins on roll motion reduction of a barge in waves is investigated experimentally. Since the system is effective even if the barge has no forward speed, it can reduce the ship motion when the barge is carrying out installation work in the ocean at zero forward speed.