Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on July 14, 2009). Includes bibliographical references.

Thesis (Ph.D.)--University of Texas at Arlington, 2009.

Thesis (Ph.D.) -- University of Adelaide, Department of Mechanical Engineering, 1978.

Thesis (M.S.)--Ohio University, August, 1998. / Title from PDF t.p.

Made available in DSpace on 2018-08-02T00:02:57Z (GMT). No. of bitstreams: 1 tese_11044_VINICIUS SCARDUA DELLACQUA.pdf: 2837961 bytes, checksum: d7e1bcd6d6b172479281b5f0bb935cd3 (MD5) Previous issue date: 2017-05-25 / A garantia de escoamento no transporte de petróleo se tornou um assunto de estudo desde que a extração de petróleo atingiu poços em águas ultra profundas. Dentre os desafios, a deposição de sólidos nos dutos de transporte, que aparecem devido ao resfriamento do sistema quando ocorre uma parada de linha, causando um bloqueio parcial ou total nos dutos e consequentemente gastos inesperados. Métodos como inibidores químicos ou o Sistema de geração de nitrogênio são utilizados para prevenir o depósito de sólidos, mas seu controle de dosagem e eficiência são difíceis de mensurar. O sistema Pipe-in-Pipe (PIP) é uma tecnologia desenvolvida que combina a utilização do isolamento térmico e do aquecimento ativo dos dutos para controle da temperatura, evitando que o PIP atinja a temperatura de formação dos sólidos. Assim, esta dissertação propõe um sistema de controle de temperatura utilizando um controlador preditivo baseado em modelo associado ao filtro de partículas (PF-MPC) para prevenir a queda de temperatura no PIP. Este esquema de controle associa a redução da incerteza de medição da temperatura feita pelo filtro de partículas (PF) com a manipulação ótimo do fluxo de calor gerado no aquecimento ativo necessário para evitar o resfriamento do PIP. O PF-MPC utiliza o modelo matemático do PIP para prever sua temperatura dentro de um horizonte de predição futuro, a partir da medição em um único ponto do PIP, é feito o cálculo da ação de controle no instante atual a fim de prevenir a queda da temperatura. O controlador estima o fluxo de calor ideal que deve ser aplicado, reduzindo os custos econômicos relacionados ao consumo energético do aquecimento ativo. Os resultados obtidos mostram que o PF-MPC permite um bom desempenho no controle da temperatura, mantendo seu objetivo de reduzir as perdas econômicas nas linhas de transporte. Palavras chave: Pipe-in-Pipe, Estimação de Estado, Filtro de Partículas, Controlador Preditivo Baseado em Modelo.

Thesis (Doctoral Engineering)--Norwegian Institute of Technology, 1992. / Includes bibliographical references (p. 8.1-8.9).

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains x, 122 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 116-122).

As vast networks of high pressure buried energy pipelines traverse North America and other continents, the stability of such essential buried infrastructure must be maintained under a variety of earth loading conditions. The pipe-soil interaction and the longitudinal behaviour of buried pipes due to relative ground movements is poorly understood. This thesis presents full scale testing and numerical modeling of steel and Glass Fibre Reinforced Polymer (GFRP) pipelines to better understand the flexural performance of buried pipes subjected to lateral earth movement. For the experimental phase of the study, a series of pipe bending experiments have been conducted on 102 mm nominal diameter and 1830 mm long steel and GFRP pipes buried in dense sand. Pipe loading was carried out by pulling pipe ends using two parallel cables attached to a spreader beam outside the test region, using a hydraulic actuator. The different tests covered burial depth-to-diameter (H/D) ratios of 3, 5 and 7. During the steel pipe testing phase, special consideration was given to assess the effect of boundary limits, friction within the pulling mechanism, and consistency of results using repeated tests. For the GFRP pipes, the experimental work investigated the effect of the laminate structure of the pipes, including both cross-ply and angle-ply laminates. Test results showed that burial depth significantly influenced the ultimate pulling forces, longitudinal strains, and pipe net deflection at mid-span. The results were also compared between the two types of pipes. The failure mechanism for all tests was consistently governed by soil failure, except for the angle-ply GFRP pipe that failed at a burial depth of H/D=7. For the numerical analysis, the study presents the development and verification of two and three-dimensional numerical models including material constitutive models for both the pipe and for the soil using a stress-dependent modulus. Calculations are presented for different burial depths and are compared to experimental data. It was shown that the numerical model can successfully capture the pipe-soil interaction behaviour for both pipe types in terms of load-displacement responses and net bending deflection. Also, the effect of material variation and laminate structure were in agreement with test data. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-04-18 22:21:53.025

No description available.

We are at a time when energy efficiency and the reduction in the use of non-renewable energy is an important objective in all aspects and will continue to be so, therefore it is necessary to try to reduce energy and heat losses in the systems used in homes and, in particular, in the domestic hot water (DHW) system. This study aims to find out the advantages and disadvantages of an innovative pipe-in-pipe (PIP) system for DHW circulation with respect to the conventional system of two separate pipes. Previous studies have shown that DHW circulation is indeed an important point of energy losses in the home and that it is possible to reduce these losses by using the innovative system under study. The properties and coefficients defining the heat transfer system have been obtained for both the traditional and innovative systems by using empirical equations and iterative processes, indicating a 32% reduction in heat losses in favour of the pipe-in-pipe system. However, this result has been obtained in a kind of case study, using some simplifying assumptions, needed to accomplish to work within limited time. So the result could vary if a somewhat different system is studied, which is why it is necessary to carry out further studies and research on this subject in order optimize DHW systems in buildings.