Roll mitigation of small fishing boat

Abstract

Heavy rolling motions experienced by small vessels give rise to many problems and disadvantages to the vessel and crew. This is undesirable especially during resonance when the encounter wave frequency coincides with the vessel natural frequency. Onboard activities, especially fishing, are affected because of difficulties due to the rolling motion. Heavy motion may lead to loss of personnel overboard or damage to onboard equipment, and also to structural failure and capsize phenomenon. The objective of this project is to develop and improve method for roll reduction and assess its performance. A Tsunami 22’ Fishermen boat and device to reduce the rolling motion have been selected for case study. The performance of the device has been analysed and tested on a model of the boat. The selected roll reduction device is a moving mass device. The moving mass device has been fabricated and evaluated its effectiveness by calm water roll decay test. It is found that the moving mass device is capable of reducing the rolling motion of the boat. The roll decay coefficient has been found increased up to 85.87%.