ROLL DAMPING COEFFICIENTS ASSESSMENT AND COMPARISON FOR ROUND BILGE AND HARD CHINE HULLFORMS

• Main Authors: BEGOVIC, ERMINA, BERTORELLO, CARLO FRANCESCO MARIO, J. Prpic Orsic
• Other Authors: Ocean, Offshore and Arctic Engineering (OMAE 2013), ASME 2013, Begovic, Ermina, Bertorello, CARLO FRANCESCO MARIO, J., Prpic Orsic
• Format: Conference Object
• Language: English
• Published: Ocean, Offshore and Arctic Engineering Division of ASME 2013
• Subjects: roll damping; hard chine versus round bilge hull; Arctic
• Online Access: http://hdl.handle.net/11588/563834

This work is focused on determination of roll damping of warped hull form at low relative speed for which little data are available. The effect of hard chine and round bilge on roll damping has been investigated for two models of same characteristics and same inertial properties in displacement and semi-displacement regime. It was expected to experience the difference between two forms in nonlinear roll damping only, which is amplitude dependent and therefore roll decay tests were performed for angles from 10 to 30 degrees at zero speed up to Fn = 0.48. Roll decays have been analyzed considering logarithmic and linear decrements. Obtained results are natural roll frequencies and periods, equivalent linear damping αEQ and linear α and quadratic β damping coefficients as functions of ship speed.