Seakeeping

• Shipbuilding, Semester 3, position 2

To cover the basic knowledge of Naval Architecture connected to ship motion in waves.

1. The student will be able to apply comprehensive knowledge from fundamental natural and technical sciences to solve problems related to ship behaviour on waves – rolling, pitching, and heaving on regular and irregular waves. Additionally, the student will be familiar with the development of wave theory and seakeeping analysis, and their significance and application to modern ship stability regulations; 2. The student will be capable of formulating problems related to seakeeping and analysing the impacts of changes in various parameters, such as changes in metacentric height, hull form, and the distribution and shifting of cargo on the ship. This will include the analysis and qualitative assessment of available data during calculations, and using engineering judgement in cases of incomplete or unreliable information; 3. The student will be able to select and apply appropriate computational and analytical techniques to model problems related to seakeeping, considering the limitations of the applied techniques; 4. The student will be able to communicate effectively on complex engineering matters of the course subject with technical and non-technical audiences, evaluating the effectiveness of the methods used.

Ship motion in calm water: rolling, heaving and pitching. Ship’s natural periods. Added mass and damping – strip theory, the Lewis forms. Waves at sea surface: hydrodynamic theory, stochastic theory. Ship motion in regular waves: rolling, heaving and pitching. Ship motion in irregular waves: motion spectra, mean, significant and RMS values of ship motion. Displacement, velocity and acceleration of ship points. Probability of deck wetness, propeller emergence and slamming. Added resistance. Effects on passengers and crew. Dynamic loads. Seakeeping criteria. Improvement of ship seakeeping characteristics. Roll stabilization.

Practical problems of seakeeping, illustrating the subjects lectured in the theoretical syllabus. In addition, students have to accomplish individually the project on ship rolling, heaving and pitching in irregular waves, for the ship already analyzed in projects of Buoyancy and Stability of Ship.

Passed course Ship buoyancy and stability 2.

[1] M. Hofman: Extracts from lectures (handouts) /In Serbian/ [2] M. Hofman and I. Bačkalov: Exercises in Seakeeping. /In Serbian/

Total assigned hours: 75

New material: 30
Elaboration and examples (recapitulation): 0

Auditory exercises: 20
Laboratory exercises: 0
Calculation tasks: 10
Seminar paper: 0
Project: 0
Consultations: 0
Discussion/workshop: 0
Research study work: 0

Review and grading of calculation tasks: 5
Review and grading of lab reports: 0
Review and grading of seminar papers: 0
Review and grading of the project: 0
Test: 0
Test: 0
Final exam: 10

Activity during lectures: 0
Test/test: 30
Laboratory practice: 0
Calculation tasks: 0
Seminar paper: 0
Project: 0
Final exam: 70
Requirement for taking the exam (required number of points): 15

Hofman, M., Ponašanje broda na talasima, Mašinski fakulte u Beogradu, I izdanje, 2020; Lewis, Edward V. (editor), Principles of Naval Architecture, Part 3, SNAME, 1987; A.R.J.M.LLoyd: Seakeeping - Ship Behaviour in Rough Weather, 1998; Lewandowski, E., The Dynamics of Marine Craft, World Scientific, 2004.