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| Author(s): |
Melquisedec Francisco dos Santos
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. , gráficos, tabelas. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2003-04-02 |
| Examining board members: |
Clovis de Arruda Martins;
Jose Augusto Penteado Aranha;
Celso Pupo Pesce;
Renato Marques Correa da Silva
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| Advisor: | Clovis de Arruda Martins |
| Field of knowledge: | Engineering - Mechanical Engineering |
| Location: | Universidade de São Paulo. Biblioteca Central da Escola Politécnica; EPBC/FT-1802; Universidade de São Paulo. Escola Politécnica. Biblioteca de Engenharia Mecânica, Naval e Oceânica; EPMN/FT-1802 |
| Abstract | |
Umbilical cables and production lines are important elements in exploration at offshore environments. The umbilical cable provides to submersed valves systems, both electric and hydraulic control signals. The production lines, flexible or rigid (steel caterary riser), are used to transport fluids like oil, gas or water. To verify the global structural response of submersed lines we used two kinds of analysis: static and dynamic analysis. The static analysis results in the static equilibrium configuration, i.e., geometry and tensions variations along the line length. By the away, the dynamic is obtained by the determination of movements and tensions variations, which parameters depends on the wave action on the line and the imposed motions of the fluctuation unit. The dynamic analysis is done in either time or frequency domain. The submersed lines project is based in static and dynamic analysis. In the analysis of submersed lines, a great number of cases needs to be simulated, due to the differents environment conditions that have to be analyzed. In the analysis static only a little time of computational simulation is necessary but the other hand, a large time processing is required by the dynamic analysis in time domain. In this case, the development of computational tools to reduce the time processing is very important. As a result of the time processing to reduce, a great number of cases can be simulated and only those that needed to be simulated in time domain,with all the non-linearities, can be analyzed. The scope of this work is the development of static\'s and dynamics linear models. The dynamic model is solved in the frequency domain, used a small time of processing. The contact between the line and the soil is an important contribution of this work, whose the contact model is based in Coulomb\'s friction law. The correction of the curvature line is other important focus of this present work. ) The boundary-layer theory is applied in top and touchdown regions but, after the development of some models of boundary-layer, it would not possible obtain a convergence of values. Meanwhile, to know the limitation of a model is as important as know the real model. (AU) | |