Untitled in english.

Author(s)

João Paulo Julião Matsuura

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 2000-11-29

Examining board members

Kazuo Nishimoto; Jose Augusto Penteado Aranha; Isaias Quaresma Masetti

• Advisor: Kazuo Nishimoto

Abstract

The rationale behind this dissertation is to present a representation and analysis methodology for the behavior of ships moored in high seas, developed by the University of Michigan. The methodology is based on the analysis of the eigenvalues ofthe ship\'s equations of motion, and allows one to obtain qualitative results about the behavior of the moored system. Some comments are made on the effects considered - such as current, wind, wave drift, and restoration, damping and drag of the mooring system - upon representation of the real moored system. Two different applications of the methodology presented in this work are developed. The first application is a comparison between various hydrodynamic models that can be used to describe the behavior of ships moored in high seas. Various characteristics and parameters from each model are compared, and the advantages and disadvantages in using each of them is assessed. The common characteristics allow one to join models in groups, easing their classification. A sensitivity analysis is also performed on the parameters, in order to check the influence each of them (or a group of them) has in the system\'s behavior. The main interest in this analysis is to identify the most critical parameters on order to obtain a greater understanding of them, as well as a focus in their experimental estimates - indicating which parameters are to be calculated more precisely than others. The second application is ananalysis of a DICAS-type mooring system, used for applications such as FSO/FPSO, for oil storage and production in high seas. Some parameters relevant to the system are selected and its range is swept, and the influence of each of them in the system\'s behavior is verified. The final objective is to identify the most influent parameters and how they affect the DICAS system\'s behavior. (AU)