Vibrações de Navios e Plataformas

Objectives

Develop an understanding of the concepts necessary to formulate structural dynamic problems. Prepare the students to understand, predict and solve the typical structural vibration problems of ships and ocean platforms. Help the students to understand the modal analysis of dynamic problems and vibration control methods.

Syllabus

Numerical solutions for the dynamic responses of simple systems. Formulation of structural dynamic problems. Dynamic analysis of discrete systems, solution of the eigenvalue problem, modal analysis. Free response of continuous systems, modal analysis. Forced responses of continuous systems. Dynamic analysis of continuous systems; axial, torsional and flexural vibrations of beams and plates. Approximate methods for analysis of continuous systems: methods of Rayleigh-Ritz, Holzer and Mikelstad. Vibrations of floating structures, natural frequencies of the ship structure and ocean plateforms, excitations due to waves, engine and propeller. Structural damping. Pratical aspects of vibration on ships and ocean platforms. Vibration control methods on ships and ocean platforms. Impact forces on the ships and ocean platforms and associated transient responses.

Prerequisites

Calculus, Matlab, Ship Strutures

Cross Competence Component

Communication, Listening,Presentation, public speaking, writing report, group work.

Laboratorial Component

Students need to perform vibration tests for a multi-degree of freedom system. The experimental equipment from the educational control products is a dynamic control system for education purpose made of three sub-systems, which are composed of masses, dampers and springs. The free and forced responses of the system will be measured and compared with numerical and theoretical calculations.

Programming And Computing Component

Students shoud be able to derive the numerical solutions for free and forced responses of simple dynamic systems using Maltab based on the theoretical formuations. The experimental data analysis shoud be dealt with Matlab in oder to compare with analytical results. For the task on flexual vibration of a ship, each group should be able to develop a Matlab code considering Myklstad method. For each task, the students should be able to derive the analytical solutions.

Ethical Principles

All members of a group are responsible for all group's work. In any assessment every student should honestly disclose any help received or sources used. In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.