Mestrado em Engenharia Ambiental e Sanitária (EEC)
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Navegando Mestrado em Engenharia Ambiental e Sanitária (EEC) por Por Orientador "Formiga, Klebber Teodomiro Martins"
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Item Modelagem do escoamento transcrítico sob regime permanente e transiente em canais(Universidade Federal de Goiás, 2021-04-27) Carvalho, Thiago Pires de; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970; Formiga, Klebber Teodomiro Martins; Vasco, Joel Roberto Guimarães; Soares, Alexandre Soares KeplerThe understanding of phenomena related to floods propagation along open channels, especially in artificial urban ones, is becoming increasingly important to avoid flooding and inundation as a result of intense precipitations. In this context, there is still great difficulty in computational modeling certain hydraulic phenomena, such as hydraulic jump, which may occur during a flood wave flow along channels under specific conditions that generate changes in flow regimes. Seeking a better understanding of this phenomenon, this work proposes the development of computational tools that simulate, through physique and mathematical equations, the propagation of flows that occur in the transition from supercritical to subcritical regimes, the so-called transcritical flow. Two computational models were developed for free-surface simulation. The first for the gradually varying permanent regime, through the Standard Step Method, as proposed by Akan (2011). The second one for the transient regime, based on solving the Saint-Venant equations in a hybrid way, where the supercritical curve was defined by the Finite Difference Method (explicit resolution) as proposed by Chaudhry (2007), and the subcritical curve was defined by the Preissmann Method (implicit resolution). Comparisons among the conjugate heights of each flow curve provided the flow transition point determination. These models were validated through laboratory tests, performed in an experimental channel, simulating different scenarios of transcritical flow, allowing the free-surface monitoring and measurement by means of a graduated ruler (experiments in gradually varying permanent regime) and ultrasonic sensors (transient regime). In particular, we aim at computational modeling the hydraulic jump phenomenon, an aproach of extreme importance and relevance for interventions in natural and artificial channels in order to promote controlled energy dissipation, regulating and stabilizing the propagation of floods and mitigating impacts downstream.Item Relações entre precipitação, escoamento e sedimentos suspensos na bacia do Rio das Antas, Goiás(Universidade Federal de Goiás, 2017-09-06) Didonet, Thais Teodoro dos Santos Cordeiro; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970; Formiga, Klebber Teodomiro Martins; Souza, Saulo Bruno Silveira e; Vasco, Joel Roberto Guimarães; Angelim, Renato Resende; Soares, Alexandre KeplerSediments transported by surface runoff and by rivers are essential components in the comprehension of changes in a river basin and the quality of aquatic systems. The high variability of rainfall events, the SSC and the relation between them produce complex behavioral dynamics difficult to interpret but the study of these aspects is a useful and frequently used tool in the quantification of impacts due to erosive and hydrossedimentological processes. The main objective of this study was to characterize and quantify the hydrological, sedimentological and granulometric characteristics of the urban watercourse of the Rio das Antas basin, located in Anápolis, Goiás, wich faces various erosion processes. Continuous monitoring of precipitation, flow rates, sediment concentrations and turbidity was performed using pluviographs, linigraphs, an automatic sampler and a laser granulometer during most of a rainy season, where samples were collected and 14 events were analyzed. Descriptive statistical analyzes, identification of hysteresis patterns, Event Mean Concentration, “first flush” phenomenon effects and grain size distribution and their relationships with precipitations and flow rates were performed. The peak concentration of total sediments reached 3,380 mg L -1 , and approximately 83% were suspended sediments. No “first flush" has been recorded in any event. The highest mean concentration observed for suspended sediments was 1,714.6 mg/m3 and the mean of the events was 1,001.3 mg/m3, values considered to be high when compared to river basin flows, where the highest was 15.49 m 3 s -1 . The maximum flow rates were determinant in the total sediment, however, the same flow range carried very different amounts of suspended sediments during the floods. This behavior suggests that the variation also depends on precipitation characteristics and sediment sources. In the hysteresis analyzes, it can be verified that these sources are located farther from the monitoring point, but are also the river itself, since the most frequent hysteresis loop was "Figure Eight" followed by the"Counter Clock-wise” type. There were complex hysteretic loops characterized by multiple peaks of flow and sediments. The size of particles carried by the flow varies throughout the rainy season. The suspended sediment particles had dimensions between 0.0019 mm and 0.990 mm being characterized as sandy silt material. The small and medium particles were more frequent in final events and larger particles occurred in the middle of the period. Finner particles were more present during the rise of the hydrograph and in the recession phase the amount of particles with dimensions between 0.2 mm e 0.6 mm increased in some events. Particles larger than 0.6 mm were not related to precipitation. It was also observed that the amount of dissolved solids decreases with increasing particle size and may indicate that larger particles have less capacity to absorb/adsorb other pollutants. It is observed that the suspended sediments vary between the events and within the same event and depends on the hydrological behavior, the characteristics of the water body and the type of monitoring.Item Análise de estimativas de precipitação por satélite e de diferentes métodos de preenchimento de falhas para a região do Sudeste Goiano(Universidade Federal de Goiás, 2018-12-19) Duarte, Luíza Virgínia; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970; Formiga, Klebber Teodomiro Martins; Souza, Saulo Bruno Silveira e; Ferreira, Nilson ClementinoPrecise estimation and monitoring of rainfall occurrence patterns are essential for the modeling of hydrological systems and the planning and management of water resources in various sectors of society. Failures in data series records may compromise studies in practical applications. Advances in precipitation physics are imperative to improve numerical models and rely heavily on testing new hypotheses for actual precipitation measurements, and improved predictions are deeply intertwined with the ability to measure precipitation. In this sense, the quality of satellite precipitation products has been significantly improved in the last decades, especially with the emergence of the missions: Tropical Rainfall Measuring Mission (TRMM) and the Global Precipitation Measurement (GPM) that comes as a successor to the TRMM mission in order to provide better global estimates of high quality and precipitation resolution. The objective of this study was to compare precipitation estimates generated by the GPM satellite with data observed on land in order to test the effectiveness of these rainfall estimates in relation to temporal and spatial patterns and to compare these data with traditional methods of filling data for the generation of complete series of data. The methods of comparison were applied for mean rainfall in the Meia Ponte and Rio dos Bois basins of the State of Goiás for daily, monthly and annual scales, and the failure completion methods were analyzed for the same region in daily and monthly data. The results were satisfactory for the monthly and annual analyzes in the region of the two basins and the daily precipitation data, due to their greater variability, they require more studies to refine the techniques in order to obtain better results.Item Monitoramento e modelagem da quantidade de água subterrânea na bacia do Córrego Botafogo, Goiânia, Goiás(Universidade Federal de Goiás, 2018-03-29) Romero, Vanessa; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970; Formiga, Klebber Teodomiro Martins; Soares, Alexandre Kepler; Araújo, José Vicente Granato deThe development of this research aimed to evaluate the behavior of the groundwater in the catchment area of the Botafogo stream in Goiânia / Goiás, through the monitoring and mathematical modeling of the free aquifer, using data from the level of the sheet, measured in the period of drought and rain, between May / 2016 and June / 2017. Monitoring was performed by measuring the groundwater level with the Water Tape electric meter in monitoring wells distributed throughout the basin. These piezometric level data helped to obtain the observed hydraulic loads and constituted input data for interpolation of the hydraulic load that entered as an initial condition in the modeling of the water table of the study área. Comparing the results of the dry period contemplated in 2016 and 2017 by this study, we noticed a greater fluctuation of groundwater level. The load contour condition defined in the calibration of the hydraulic conductivity of the Botafogo basin was of local flow, making possible the estimation of the recharge and the calculation of the outflow in the basin in permanent regime. In the transient flow regime, it was observed that, with the increase of hydraulic conductivity, the level of the water table rose, in the zone downstream of the Botafogo basin, but remained continuous over time, in terms of the highest value calibrated for the parameter storage (0.48 m³/day). Therefore, the fluctuation of the groundwater level in the catchment area of the Botafogo basin can be reflected both in the recharge caused by the precipitation and in the variation of the hydraulic load (the increase of which tends to degrade the water table).