Abstract :

The most recent ships incorporate a number of significant design enhancements to improve the vessel’s seaworthiness. Bulbous bow, bilge keel, stern wedge, stern tunnel, spray rails, and others are examples. A stern wedge is a small modification of the buttock lines aft of station 19 1/2. The use of this hull design feature on small high-speed planning craft for the purpose of improved powering performance is an accepted naval architectural practice. However, its use on fishing vessels is uncommon. A bilge keel is a marine gear that reduces the tendency for a ship to roll. Hull shape modifications such as bilge keel can potentially increase safety by reducing roll motions. These enhancements have not been adopted or evaluated on fishing vessels, despite the fact that they have been employed on seagoing ships. The installation of bilge keels on fishing vessels was found to have a significant influence on the roll motion of the vessels, boosting their safety and efficiency. When compared to normal trawlers, the installation of bilge keels increased roll period by at least 40% and reduced roll amplitude by 16%.

---

Keywords :

Bilge keel, Resistance, Roll decay simulation, Roll motion, Seakeeping, Stern wedge, Trawler.

---

References :

1. Galappaththi, U.I.K., Jayathunga R.D.S., 2019 , The Effect of Drag Force Reduction for Fuel Efficiency Optimization of Fishing Vessels , Proceedings of the 6th Annual Research Symposium, University of Ruhuna.
2. Praveen, D.S.Ch., Kumar, S., Bhattacharyya, V., 2021 , Design study of stern tunnel wedge shapes for a low draft shallow water vessel, Taylor & Francis Group.
3. Kiryanto, Hadi, E.S., Firdhaus, A., 2019, Total resistance analysis on bow form model ulstein X-bow with various angle of flare and stem angle, Department of Naval Architecture, Faculty of Engineering, Diponegoro University, Semarang, Indonesia
4. Liu, W., Demirel, Y.K., Djantmiko, E.K.,2018, Bilge keel design for the traditional fishing boats of Indonesia’s East Java , International Journal of Naval Architecture and Ocean Engineering.
5. Molland, A.F.,Turnock, S.R., Hudson, D.A., 2011, Ship resistance and propulsion, Cambridge, New York, Cambridge University press
6. Baiju M. V., Vipin Kumar V., Dhiju Das P. H., Muhammed Sherief P. S., Leela Edwin, 2017, Mechanised Fishing Vessels of India, Cochin, Central Institute of Fisheries Technology
7. Andersen, P. and Guldhammer, H. (1986), Resistance Estimates – Guldhammer and Harvald’s Method, Fundamentals of Ship Hydrodynamics: Fluid Mechanics, Ship Resistance and Propulsion, John Wiley & Sons Ltd., Washington, DC, USA.