Unapređenje grednog konačnog elementa za analizu brodske konstrukcije

master's thesis

• Title (english): Improvement of beam finite element for ship structural analysis
• Author: Marin Palaversa
• Mentor: Pero Prebeg (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2015-01-23, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding

Abstract

U radu su opisane formulacije grednog konačnog elementa: hibridna, obična ekscentrična i modificirana ekscentrična koje se najčešće upotrebljavaju u analizi odziva brodskih konstrukcija. Ispitana je njihova točnost kod proračuna čvornih pomaka i normalnog aksijalnog naprezanja u odnosu na model s finom mrežom te je dana i njihova međusobna usporedba. Uočeni su problemi kod proračuna unutrašnje aksijalne sile i s njom povezanih naprezanja kod običnog ekscentričnog grednog elementa te je predložena korekcija. Izveden je i gredni konačni element sa sedam stupnjeva slobode te su pokazani njegovi nedostaci. Na kraju rada je opisan još i ljuskasti element koji je, uz modificirani ekscentrični gredni konačni element, ugrađen u program PLO2X te je prikazan detaljni proračun čvornih pomaka, unutrašnjih sila i naprezanja za promatranu konstrukciju.

Abstract (english)

Hybrid, native eccentric and modified eccentric beam finite element formulations, most commonly employed in the analysis of the strength of ship structures, are described and discussed in this work. Their accuracy in terms of the nodal displacements and normal axial stresses is tested against a fine mesh model and they are also compared to each other. Existence of error in calculation of internal axial force and related stresses when native eccentric beam element is used was demonstrated and certain correction is proposed. A seven-degrees-of-freedom element is presented as well as the negative aspects of its use. At the end shell element implemented in PLO2X software together with modified eccentric beam element is described as well as detailed calculation of nodal degrees of freedom, internal forces and stresses for structure considered in this work.

• Keywords: čvrstoća broda; metoda konačnih elemenata; gredni konačni element; hibridni gredni element; ekscentrični gredni element; modificirani ekscentrični gredni element; PLO2
• Keywords (english): strength of ship structures; finite element method; beam finite element; hybrid beam element; eccentric beam element; modified eccentric beam element; PLO2
• Language: croatian
• URN:NBN: urn:nbn:hr:235:499826
• Study programme: Title: Naval Architecture; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka brodogradnje (magistar/magistra inženjer/inženjerka brodogradnje)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-27 13:59:04