Nelinearno ljuljanje i prevrtanje broda

scientific master's theses

• Title (english): Nonlinear ship rolling and capsizing
• Author: Marta Pedišić Buča
• Mentor: Ivo Senjanović (mentor)
• Committee member: Većeslav Čorić (predsjednik povjerenstva)
• Committee member: Ivo Senjanović (član povjerenstva)
• Committee member: Izvor Grubišić (član povjerenstva)
• Committee member: Andreja Werner (član povjerenstva)
• Committee member: Jasna Prpić-Oršić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2005-10-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding
• Universal decimal classification (UDC): 629.5 - Watercraft engineering

Abstract

Istraživanja na području sigurnosti broda u cilju poboljšavanja postojećih pravila o sigurnosti vrlo su aktualna tema iz područja brodogradnje. U radu su prikazana postojeća pravila o stabilitetu broda, uz poseban osvrt na stabilitet broda protiv prevrtanja. Postavljena je raspregnuta jednadžba ljuljanja broda te je dan prikaz metoda za rješavanje nelinearnog ljuljanja broda na harmonijskom valu i morskim valovima kao i prikaz metoda za određivanje vjerojatnosti prevrtanja broda. Proveden je proračun ljuljanja odabranog broda na harmonijskom valu i na morskim valovima primjenom metode harmonijskog ubrzanja. Analizirani su nelinearni fenomeni u odzivu. Problem vjerojatnosti određivanja prevrtanja broda rješavan je metodom erozije bazena. Kao ilustrativni primjer korišten je trajekt za prijevoz putnika i vozila, a obrađene su sljedeće varijante : brod u neoštećenom stanju – varijanta sa i bez ljuljnih kobilica i brod u oštećenom stanju. Temeljem ovih izračuna predlažu se novi kriteriji o stabilitetu broda korištenjem dijagrama preživljavanja broda, kao alata dobivenog temeljem recentnih dostignuća nelinearne dinamike, a jednostavnog za primjenu. Ovaj bi se dijagram mogao koristiti kako tijekom projektiranja tako i tijekom eksploatacije za procjenu sigurnosti broda protiv prevrtanja, a omogućio bi objedinjavanje saznanja projektanata i podataka s brodova tijekom eksploatacije.

Abstract (english)

Investigation of ship safety ( especially safety against capsizing ) concerning the existing ship safety criteria is very topical area in shipbuilding. In this work the existing ship stability rules are presented, with special reference to stability against capsizing. An uncoupled equation of ship rolling is set and the methods for solving nonlinear ship rolling in regular and irregular waves are presented. The methods for calculating probability of ship capsizing are also presented. Calculations of rolling for a particular ship in regular and irregular waves are done using the harmonic acceleration method. Nonlinear response phenomena are analysed. Probability of ship capsizing is determined via “basin erosion” method of nonlinear dynamics. As illustrative example passengers / vehicles ferry is used. Intact ship condition with and without bilge keels and damaged ship conditions are investigated. Based on these calculations new criteria for ship stability are recommended based on the use of the ship survivability diagrams. This diagram is a tool for determination of the ship capsizing probability obtained via methods of nonlinear dynamics, but simple for use. It could be useful during ship designing and ship’s service, and it would enable uniting knowledges of naval architetcs and informations gained from ship’s crew.

• Keywords: sigurnost broda; stabilitet broda; ljuljanje broda; prevrtanje broda; nelinearna dinamika; teorija kaosa; sposobnost preživljavanja broda
• Keywords (english): ship safety; ship stability; ship rolling; ship capsizing; nonlinear dynamics; chaos theory; ship survivability
• Language: croatian
• URN:NBN: urn:nbn:hr:235:723651
• Study programme: Title: Naval Architecture - mr.sc.; Study programme type: university; Study level: postgraduate; Academic / professional title: magistar znanosti (magistar znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2020-12-28 10:24:35