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@PhDThesis{Nunes:2008:EsAnNu,
               author = "Nunes, Andr{\'e} Becker",
                title = "Crescimento da camada limite convectiva: estudo anal{\'{\i}}tico 
                         e num{\'e}rico",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2008",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2008-10-09",
             keywords = "camada limite planet{\'a}ria, modelagem anal{\'{\i}}tica, 
                         simula{\c{c}}{\~a}o de grandes v{\'o}rtices, crescimento da 
                         convec{\c{c}}{\~a}o, resolu{\c{c}}{\~a}o de grade. planetary 
                         boundary layer, analytical modeling, large eddy simullation, 
                         growth of convection, grid resolution.",
             abstract = "Com o avan{\c{c}}o computacional, a modelagem num{\'e}rica da 
                         turbul{\^e}ncia atmosf{\'e}rica tem sido de valiosa 
                         import{\^a}ncia na an{\'a}lise da f{\'{\i}}sica da Camada 
                         Limite Planet{\'a}ria (CLP). Neste {\^a}mbito, destaca-se a 
                         Simula{\c{c}}{\~a}o de Grandes V{\'o}rtices (LES). O modelo 
                         LES, vastamente empregado em estudos micrometeorol{\'o}gicos, tem 
                         como objetivo a simula{\c{c}}{\~a}o direta dos grandes 
                         v{\'o}rtices, fen{\^o}menos da escala resolvida, e 
                         parametriza{\c{c}}{\~a}o dos pequenos v{\'o}rtices, de escala 
                         de subgrade. Contudo, al{\'e}m do desenvolvimento de 
                         processamentos cada vez mais r{\'a}pidos e robustos, a modelagem 
                         num{\'e}rica depende, essencialmente, da elabora{\c{c}}{\~a}o 
                         de modelos anal{\'{\i}}ticos. Por outro lado, a modelagem 
                         num{\'e}rica auxilia na comprova{\c{c}}{\~a}o de modelos 
                         te{\'o}ricos, principalmente quando consegue substituir dados 
                         observacionais dif{\'{\i}}ceis de serem obtidos. Desta forma, o 
                         objetivo desta tese {\'e} a verifica{\c{c}}{\~a}o de duas 
                         metodologias te{\'o}ricas por meio do modelo LES. A primeira 
                         {\'e} baseada na escolha de grade a ser selecionada em uma 
                         simula{\c{c}}{\~a}o num{\'e}rica. Aqui, o modelo LES comprova a 
                         coer{\^e}ncia da teoria que sugere uma restri{\c{c}}{\~a}o 
                         f{\'{\i}}sica, a altura do topo da camada convectiva, para a 
                         determina{\c{c}}{\~a}o do espa{\c{c}}amento de grade. A escolha 
                         da resolu{\c{c}}{\~a}o a ser empregada em um modelo 
                         num{\'e}rico era, at{\'e} ent{\~a}o, subjetiva, pois baseava-se 
                         no n{\'u}mero m{\'a}ximo de pontos que a estrutura computacional 
                         dispon{\'{\i}}vel conseguisse calcular em um tempo 
                         razo{\'a}vel. Tal escolha poderia gerar um gasto computacional 
                         excessivo ou perda de informa{\c{c}}{\~a}o. A segunda teoria 
                         desenvolvida nesta tese {\'e} a modelagem anal{\'{\i}}tica da 
                         fase de transi{\c{c}}{\~a}o matutina, baseada na 
                         equa{\c{c}}{\~a}o de espectro tridimensional do crescimento da 
                         convec{\c{c}}{\~a}o - quest{\~a}o ainda em aberto na literatura 
                         micrometeorol{\'o}gica e, portanto, principal 
                         contribui{\c{c}}{\~a}o deste trabalho. O pleno entendimento da 
                         CLP depende da an{\'a}lise das fases de transi{\c{c}}{\~a}o. 
                         Aqui, discute-se a fase matutina, per{\'{\i}}odo do ciclo diurno 
                         menos estudado no meio cient{\'{\i}}fico. No desenvolvimento do 
                         modelo anal{\'{\i}}tico apresentado neste trabalho emprega-se um 
                         conjunto de formula{\c{c}}{\~o}es (metodologias de 
                         convers{\~a}o de espectro unidimensional em tridimensional, 
                         equa{\c{c}}{\~o}es de espectro unidimensional, vari{\^a}ncias 
                         de velocidade, taxas de dissipa{\c{c}}{\~a}o) que, ao serem 
                         inseridas na equa{\c{c}}{\~a}o de espectro do crescimento, geram 
                         quatro modelos anal{\'{\i}}ticos. A precis{\~a}o destes modelos 
                         {\'e} comprovada por meio da compara{\c{c}}{\~a}o entre a 
                         energia cin{\'e}tica turbulenta (ECT) gerada analiticamente e a 
                         ECT gerada pelo modelo LES. Entretanto, para 
                         verifica{\c{c}}{\~a}o da coer{\^e}ncia dos resultados do modelo 
                         LES, previamente foi necess{\'a}ria a simula{\c{c}}{\~a}o 
                         num{\'e}rica do ciclo diurno (camada convectiva, decaimento, 
                         camada neutra, crescimento e camada convectiva novamente), o que 
                         possibilitou uma proveitosa discuss{\~a}o dos diferentes regimes 
                         turbulentos da CLP. Portanto, conclui-se que os resultados 
                         alcan{\c{c}}ados nesta tese contribuem decisivamente na escolha 
                         da resolu{\c{c}}{\~a}o de grade a ser adotada em 
                         simula{\c{c}}{\~o}es convectivas e, principalmente, na modelagem 
                         e discuss{\~a}o da camada limite matutina. ABSTRACT: With the 
                         computational progress, numerical modeling has been very important 
                         in the physics of Planetary Boundary Layer (PBL) analysis. In this 
                         scope, it emphasizes the Large Eddy Simulation (LES). The LES 
                         model, broadly employed in meteorological studies, aims the direct 
                         simulation of large eddies, resolved scales phenomena, and 
                         parameterizes the small ones, subgrid scale phenomena. However, 
                         beyond the development of processing more and more quick and 
                         massive, the numerical modeling essentially depends on the working 
                         out of analytical modeling. On the other hand, numerical modeling 
                         contributes in the proof of theoretical models, mainly when it is 
                         able to substitute difficult to be obtained observed data. In this 
                         way, the objective of this work is the verifying of two 
                         theoretical methodologies through the employment of LES model. The 
                         first one is based on the grid resolution to be chosen in a 
                         numerical simulation. Here, LES model proofs the coherence of the 
                         theory that suggests a physical criterion, the convective layer 
                         top height, to determinate the grid spacing. The choice of the 
                         resolution to be employed in a numerical model was, so far, 
                         subjective, since it was based on the maximum number of points 
                         that the disposable computational structure was able to computing 
                         under a reasonable time. Such choice could generate an excessive 
                         computing spent or lost of information. The second theory 
                         developed in this thesis is the analytical modeling of morning 
                         transition phase, based on equation of convection growing 
                         three-dimension spectrum still open question in 
                         micrometeorological literature and, hence, the main contribution 
                         of this work. The full understanding of PBL depends on the 
                         transition phases analysis. Here, it is argued about morning 
                         phase, less studied period of diurnal cycle in the scientific 
                         knowledge. In the development of analytical model presented in 
                         this work is employed a set of formulations (conversion of 
                         one-dimension to three-dimension spectrum methodologies, 
                         one-dimension spectrum equations, velocity variances, dissipation 
                         rates) which, inserted in the growing spectrum equation, generates 
                         four analytical models. The accuracy of such models is proved 
                         through a comparison between the turbulent kinetic energy (TKE) 
                         generated analytically and the TKE generated by LES. Nevertheless, 
                         to verifying the LES results coherence, was previously made a 
                         numerical simulation of diurnal cycle (convective layer, decay, 
                         neutral layer, growth and convective layer again), what resulted 
                         in a useful discussion about different turbulent regimes in CLP. 
                         Therefore, it concludes that the results obtained in this thesis 
                         contribute well on the grid resolution choice to be adopted on 
                         convective simulations and, principally, in the modeling and 
                         discussion of morning boundary layer.",
            committee = "Fisch, Gilberto Fernando (presidente) and Satyamurty, Prakki 
                         (orientador) and Campos Velho, Haroldo Fraga de (orientador) and 
                         Oliveira, Amauri Pereira de and Acevedo, Ot{\'a}vio Costa",
           copyholder = "SID/SCD",
         englishtitle = "Convective boundary layer growth: numerical and analytical study",
             language = "pt",
                pages = "192",
                  ibi = "8JMKD3MGP8W/34C5U9H",
                  url = "http://urlib.net/rep/8JMKD3MGP8W/34C5U9H",
           targetfile = "publicacao.pdf",
        urlaccessdate = "18 jan. 2021"
}


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