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@PhDThesis{Tessarolo:2017:VaApVa,
               author = "Tessarolo, Luciana de Freitas",
                title = "Modelo num{\'e}rico para libera{\c{c}}{\~o}es de {\'o}leo e 
                         g{\'a}s em {\'a}guas profundas: valida{\c{c}}{\~a}o e 
                         aplica{\c{c}}{\~o}es em vazamentos hipot{\'e}ticos",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-08-23",
             keywords = "vazamento de {\'o}leo e g{\'a}s, modelo de vazamento de 
                         {\'o}leo e g{\'a}s, plumas subaqu{\'a}ticas, jatos e plumas de 
                         {\'o}leo e g{\'a}s, {\'o}leo e g{\'a}s em {\'a}guas 
                         profundas. oil and gas blowout, model for oil and gas blowout, 
                         underwater plumes, jets and plumes of oil and gas, oil and gas in 
                         deepwater.",
             abstract = "O crescimento da produ{\c{c}}{\~a}o mundial de petr{\'o}leo e 
                         g{\'a}s natural {\'e} motivo de aten{\c{c}}{\~a}o devido ao 
                         risco de ocorrerem acidentes que resultem em consequ{\^e}ncias 
                         danosas para a popula{\c{c}}{\~a}o, para a economia e para o 
                         meio ambiente. Uma importante ferramenta que pode ser utilizada 
                         para auxiliar na elabora{\c{c}}{\~a}o de planos de 
                         conting{\^e}ncia para o atendimento de emerg{\^e}ncias 
                         envolvendo vazamentos {\'e} a modelagem num{\'e}rica. 
                         Atrav{\'e}s da simula{\c{c}}{\~a}o de diversos cen{\'a}rios, o 
                         comportamento da pluma de {\'o}leo e g{\'a}s pode ser 
                         determinado, proporcionando agilidade para as tomadas de 
                         decis{\~a}o. Com base nessa import{\^a}ncia, o objetivo desse 
                         trabalho foi construir um modelo num{\'e}rico Lagrangiano para 
                         determinar o comportamento do {\'o}leo e do g{\'a}s em caso de 
                         vazamentos a partir de {\'a}guas profundas. Nesse modelo, o modo 
                         como as got{\'{\i}}culas de {\'o}leo e as bolhas de g{\'a}s 
                         descrevem sua trajet{\'o}ria e interagem com o meio foi formulado 
                         em dois est{\'a}gios: din{\^a}mico, no qual a din{\^a}mica 
                         inicial da mistura de {\'o}leo, g{\'a}s, {\'a}gua e hidrato 
                         determina o transporte da pluma, e advectivo-difusivo, no qual 
                         processos de advec{\c{c}}{\~a}o e difus{\~a}o dominam o 
                         transporte das part{\'{\i}}culas ap{\'o}s a pluma 
                         alcan{\c{c}}ar o n{\'{\i}}vel de flutuabilidade neutra, onde o 
                         est{\'a}gio din{\^a}mico torna-se negligenci{\'a}vel. Em cada 
                         fase, os processos f{\'{\i}}sico-qu{\'{\i}}micos que alteram a 
                         massa e a concentra{\c{c}}{\~a}o dos componentes da pluma foram 
                         considerados. Primeiramente, o modelo num{\'e}rico foi validado 
                         utilizando experimentos de laborat{\'o}rio e de campo, avaliando 
                         isoladamente os processos de entranhamento de {\'a}gua, 
                         forma{\c{c}}{\~a}o/dissolu{\c{c}}{\~a}o/decomposi{\c{c}}{\~a}o 
                         de hidrato, dissolu{\c{c}}{\~a}o de g{\'a}s e {\'o}leo, e 
                         escape do g{\'a}s a partir da pluma. Para todos os 
                         par{\^a}metros analisados, os resultados fornecidos pelo modelo 
                         concordaram de forma satisfat{\'o}ria com os valores observados. 
                         Em seguida, para avaliar o modelo considerando os processo 
                         combinados, um experimento com descargas reais de plumas de 
                         {\'o}leo/g{\'a}s/{\'a}gua a partir de {\'a}guas profundas foi 
                         simulado, sendo obtidas trajet{\'o}rias semelhantes {\`a}quelas 
                         observadas. Ap{\'o}s a valida{\c{c}}{\~a}o do modelo, foram 
                         realizadas simula{\c{c}}{\~o}es de vazamentos hipot{\'e}ticos 
                         de {\'o}leo e g{\'a}s em po{\c{c}}os atualmente em fase de 
                         produ{\c{c}}{\~a}o nos Campos de Frade - Bacia de Campos e de 
                         Lula - Bacia de Santos. Em cada po{\c{c}}o, foram simuladas 
                         descargas nos meses de Janeiro/2016 e Julho/2016, a fim de se 
                         verificar o efeito da varia{\c{c}}{\~a}o sazonal do meio no 
                         comportamento da pluma. Os resultados mostraram que as 
                         trajet{\'o}rias do {\'o}leo e do g{\'a}s seguiram a 
                         dire{\c{c}}{\~a}o das correntes oce{\^a}nicas. Para os 
                         experimentos no Campo de Frade (Exps. CF-JAN e CF-JUL), as maiores 
                         got{\'{\i}}culas de {\'o}leo foram as primeiras a 
                         alcan{\c{c}}ar a superf{\'{\i}}cie, 2 h ap{\'o}s o 
                         in{\'{\i}}cio da descarga, enquanto que as menores ascenderam de 
                         forma mais lenta, emergindo ap{\'o}s 6, 7 h. Desde o fundo do mar 
                         at{\'e} z = \−300 m, o {\'o}leo deslocou-se para 
                         Noroeste. Acima dessa profundidade, as got{\'{\i}}culas seguiram 
                         para as dire{\c{c}}{\~o}es Sudeste e Sudoeste, respectivamente, 
                         nos Exps. CF-JAN e CF-JUL, influenciadas pela invers{\~a}o das 
                         correntes oce{\^a}nicas. Nos dois casos simulados, 6\% da massa 
                         inicial do {\'o}leo foram dissolvidas no meio durante seu 
                         deslocamento na coluna de {\'a}gua. O comportamento das bolhas de 
                         g{\'a}s em ambos os experimentos foi bastante semelhante. O 
                         g{\'a}s contido nas bolhas foi completamente convertido em 
                         cristais de hidrato logo nos primeiros minutos. As bolhas seguiram 
                         a dire{\c{c}}{\~a}o Noroeste, atingindo a profundidade 
                         m{\'a}xima de z = \−545 m e tendo a massa de g{\'a}s 
                         completamente dissolvida no meio em um intervalo de 2 h. Nos dois 
                         experimentos no Campo de Lula (Exps. CL-JAN e CL-JUL), enquanto as 
                         got{\'{\i}}culas maiores levaram cerca de 2, 6 h para chegar em 
                         superf{\'{\i}}cie, as de menor tamanho afloraram 7, 6 h 
                         ap{\'o}s o in{\'{\i}}cio da libera{\c{c}}{\~a}o. No Exp. 
                         CL-JAN (CL-JUL), o {\'o}leo deslocou-se para Noroeste (Sudoeste) 
                         at{\'e} z = \−600 m (z = \−400 m), mudando para 
                         Sudeste (levemente para Noroeste) acima dessa profundidade, 
                         seguindo as varia{\c{c}}{\~o}es na dire{\c{c}}{\~a}o das 
                         correntes. Ao computar a dissolu{\c{c}}{\~a}o do {\'o}leo na 
                         coluna de {\'a}gua, verificou-se que 9, 3% da massa inicial foram 
                         perdidas para o meio. Nessas duas simula{\c{c}}{\~o}es no Campo 
                         de Lula, a cobertura de hidrato tamb{\'e}m foi rapidamente 
                         formada ao redor das bolhas de g{\'a}s. As bolhas deslocaram-se 
                         para Noroeste (Sudoeste) no Exp. CL-JAN (CL-JUL) e n{\~a}o 
                         afloraram em superf{\'{\i}}cie. O g{\'a}s foi completamente 
                         dissolvido no meio em um intervalo de 2, 95 h e a profundidade 
                         m{\'a}xima alcan{\c{c}}ada pelas bolhas foi z = \−611 m 
                         (z = \−576 m). ABSTRACT: The growth of the world production 
                         of oil and natural gas increases the risk of accidents resulting 
                         in harmful consequences for the population, the economy and the 
                         environment. An important tool that can be used to elaborate 
                         contingency plans for the emergency treatment involving blowouts 
                         is the numerical modeling. From the simulation of several 
                         scenarios, the behavior of the oil and gas plume can be 
                         determined, providing agility in the decision making. Motivated by 
                         these necessities, the objective of this research was to build a 
                         Lagrangian numerical model to assess the behavior of the oil and 
                         gas in case of deepwater blowouts. In this model, how the oil 
                         droplets and gas bubbles describe their trajectory and interact 
                         with the environment was formulated in two stages: dynamic, in 
                         which the initial dynamics of the mixture of oil, gas, water and 
                         hydrate determines the plume transport, and advection-diffusion, 
                         in which advection and diffusion processes govern the particles 
                         transport after the plume reaches the neutral buoyancy level, 
                         where the dynamic stage becomes negligible. In each phase, the 
                         physical-chemical processes that change the mass and the 
                         concentration of the plume components were considered. First, the 
                         numerical model was validated using laboratory and field 
                         experiments, evaluating separately the processes of entrainment of 
                         water, formation/dissolution/decomposition of hydrate, oil and gas 
                         dissolution, and separation of gas from the plume. For all the 
                         analyzed processes, the model reproduced satisfactorily the 
                         observations. Afterwards, all processes were considered in an 
                         experiment simulating real deepwater discharges of 
                         oil/gas/seawater, and the trajectories obtained were very similar 
                         to those observed. After the model validation, simulations of 
                         hypothetic blowouts of oil and gas from oil wells currently in 
                         phase of production in Frade Oil Field - Campos Basin and Lula Oil 
                         Field - Santos Basin were performed. In each oil well, discharges 
                         were simulated on January/2016 and July/2016, in order to verify 
                         the effects of the seasonal variation of the environment 
                         conditions on the plume behavior. The results showed the oil and 
                         gas trajectories following the direction of the ocean currents. 
                         For the experiments in Frade Oil Field (Exps. CF-JAN and CF-JUL), 
                         the biggest oil droplets were the first to reach the surface, 2 h 
                         after the beginning of the discharge, while the smallest rose 
                         slowly, emerging after 6.7 h. From the sea floor to z = 
                         \−300 m, the oil moves toward the Northwest. Above this 
                         depth, the droplets flowed Southeastward and Southwestward in 
                         Exps. CF-JAN and CF-JUL, respectively, due to ocean currents 
                         variations. In these two experiments, 6% of the initial mass of 
                         oil were dissolved into the environment. The behavior of the gas 
                         bubbles in both experiments was very similar. The gas inside the 
                         bubbles was completely converted in hydrate crystals in the first 
                         few minutes. The bubbles flowed Northwestward, reaching the 
                         maximum depth of z = \−545 m and their gas mass was 
                         completely dissolved into the environment in 2 h. For the two 
                         experiments in Lula Oil Field (Exps. CL-JAN and CL-JUL), while the 
                         biggest oil droplets spent about 2.6 h to reach the surface, the 
                         smallest emerged 7.6 h after the beginning of the discharge. In 
                         Exp. CL-JAN (CL-JUL), the oil moved toward the Northwest 
                         (Southwest) until z = \−600 m (z = \−400 m), 
                         changing toward the Southeast (lightly toward the Northwest) above 
                         this depth, following the currents direction. About 9.3% of the 
                         initial mass were lost to the environment. In these two 
                         simulations in Lula Oil Field, hydrate shells were formed quickly 
                         around the gas bubbles. In Exp. CL-JAN (CL-JUL), the bubbles 
                         flowed Northwestward (Southwestward) and were fully dissolved into 
                         the environment in 2.95 h and the maximum depth reached by the 
                         bubbles was z = \−611 m (z = \−576 m).",
            committee = "Chan, Chou Sin (presidente) and Innocentini, Valdir (orientador) 
                         and Pezzi, Luciano Ponzi and Cabral, Marcelo Montenegro and 
                         Miranda, Fernando Pellon de and Martins, Renato Parkinson and 
                         Sartori Neto, Angelo",
         englishtitle = "Numerical model for oil and gas releases from deepwater: 
                         validation and applications in hypothetical blowouts",
             language = "pt",
                pages = "256",
                  ibi = "8JMKD3MGP3W34P/3PGB5GL",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3PGB5GL",
           targetfile = "publicacao.pdf",
        urlaccessdate = "28 nov. 2020"
}


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