Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-23T20:11:00Z (GMT). No. of bitstreams: 1 Mortatti_BrunoCesar_M.pdf: 2082666 bytes, checksum: 0035bd7ef41b771d365f948dd694e18a (MD5) Previous issue date: 2013 / Resumo: Dois permeâmetros de carga constante e grandes dimensões, com 0,057 e 0,042 metros cúbicos, respectivamente, foram utilizados em laboratório, sob condições controladas, para as determinações das condutividades hidráulicas saturadas de Resíduos Sólidos Urbanos (RSU) coletados no Aterro Sanitário Delta A, localizado na cidade de Campinas-SP. Duas fases experimentais foram delineadas envolvendo diferentes parâmetros como composição gravimétrica e grau de compactação. Para cada fase experimental foram realizados vários ensaios para as determinações das condutividades hidráulicas saturadas em função dos tempos de operação dos permeâmetros e levantamento das principais variáveis físicas envolvidas neste processo, como teor de umidade, capacidade de campo, carga hidráulica e vazão. Simultaneamente, os lixiviados oriundos de cada ensaio realizado foram coletados e monitorados pelas análises dos principais parâmetros e espécies químicas para avaliação das etapas envolvidas no processo de biodegradação dos RSU. As condutividades hidráulicas saturadas, determinadas nos ensaios realizados, variaram de 1,6E-02 a 5,7E-05 m/s em função dos diferentes graus de compactação. Algumas variáveis químicas se mostraram eficientes na identificação das etapas de biodegradação, como potencial redox, ácidos orgânicos voláteis, nitrogênio amoniacal, acetato e carbono total dissolvido. O comportamento dessas variáveis em função dos tempos de operação permitiu a identificação das etapas acidogênica/acetogênica na biodegradação dos RSU / Abstract: Two constant load and large dimensions permeameters, with 0.057 and 0.042 cubic meters, respectively, were used in laboratory, under controlled conditions, for the determination of saturated hydraulic conductivity of Municipal Solid Waste (MSW) collected in the Delta A Sanitary Landfill, located at city of Campinas-SP. Two experimental phases were outlined involving different parameters such as gravimetric composition and degree of compression. For each experimental phase were carried out various tests for the determination of satured hydraulic conductivity as a function of the operation times of the permeameters and physical survey of the main variables involved in this process, such as, moisture content, field capacity, hydraulic head and volumetric flow rate. Simultaneously, the leachates coming of each test performed were collected and monitored by the analysis of the main parameters and chemical species for evaluation of the steps involved in the biodegradation of MSW. The saturated hydraulic conductivities, determined in tests, ranged from 1.6E-02 to 5.7E-05 m/s for different degrees of compression. Some chemical variables such as redox potential, volatile fatty acids, ammoniac nitrogen, acetate and dissolved total carbon, were effective in identifying the stages of biodegradation. The behavior of these variables as a function of time of operation allowed the identification of the acidogenic/acetogenic steps in the biodegradation of the MSW / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

Orientador: Elias Basile Tambourgi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-19T18:15:28Z (GMT). No. of bitstreams: 1 Pereira_FlavioNelson_M.pdf: 3206674 bytes, checksum: 13d3a08e501d1a7a3efe94db596a1123 (MD5) Previous issue date: 2011 / Resumo: A bomba centrífuga é uma máquina dinâmica que só pode trabalhar nos pontos de sua curva. Consequentemente, a soma das resistências da tubulação e seus componentes durante a operação deve se situar exatamente na sua curva ou curva da bomba. A literatura para a seleção e especificação deste equipamento alimentando apenas um ponto como um tanque ou vaso é vasta, porém, são raros os trabalhos no que concerne a alimentação simultânea de dois ou mais tanques em cotas diferentes, que mostrem o comportamento da pressão ao longo do processo e a curva desse sistema. Esta alimentação simultânea é dita ramificada. O presente trabalho teve por objetivo projetar e montar uma unidade experimental em escala piloto para determinar a curva do sistema e a potência consumida de uma bomba centrífuga quando esta alimenta dois tanques em cotas diferentes utilizando a água como fluido referência, com viscosidade de 1,0 cP e também uma solução de açúcar a 1,2 cP. A unidade consistiu de um tanque de alimentação de 162,5 L construído em acrílico, uma bomba centrífuga com diâmetro do rotor de 200 mm acoplado a um motor em balanço de 2 CV de potência nominal, um inversor de freqüência para controlar a rotação do motor, tubulações de PVC transparentes de 1 in. de diâmetro nominal na descarga da bomba, um rotâmetro com escala de 0 - 12 m3/h, manômetro com escala 0 - 4 kgf/cm2, e dois tanques em acrílico de 72 L cada na descarga instalados em cotas diferentes. A unidade experimental que operou em regime permanente permitiu a verificação da vazão total e, por conseqüência, a determinação da vazão real em cada trecho ramificado. Os poucos trabalhos teóricos nesta área não comprovam experimentalmente a teoria, não analisam a influência de propriedades físicas e nem estimam a potência do motor. O experimento, portanto, procura comparar os dados coletados com a teoria utilizando fluidos com propriedades físicas diferentes. Este trabalho permitiu comparar os valores teóricos e experimentais com desvio de 12,5 a 20,5%, sendo proposta uma sequência teórica dividida em passos para a determinação do ponto de operação do sistema. O emprego desta sequência proposta permite reduzir os custos de instalação evitando malhas de controle, e os custos operacionais com a redução da energia consumida em sistemas industriais / Abstract: A centrifugal pump is a dynamic machine that can perform only on points on the head capacity curve or curve pump. Consequently, the sum of piping and components resistances during operation must fall exactly on the head capacity curve. The literature for the selection and specification of this equipment feeding only one point as a tank or vessel is large, however is hard to find studies regarding the simultaneous feeding of two or more tanks in different heights and showing the pressure behavior during process and the system curve. This simultaneously feeding is said branched. This study aimed to design and build a pilot-scale experimental unit to determine the system curve and the power consumption of a centrifugal pump when it feeds two tanks in different heights using in fluid viscosity of 1.0 cP, water as fluid reference as well sugar solution to 1.2 cP. The unit consisted of a feed tank of 162.5 L built in acrylic, centrifugal pump with a rotor diameter of 200 mm combined with a balance of motor 2 hp rated power, a frequency inverter to control the engine speed, PVC pipes in a transparent 1 in.nominal discharge of the pump, a flowmeter with a scale from 0 to 12 m3/ h, pressure gauge with a scale from 0 to 4 kgf/cm2, and two tanks of 72 L each in discharge also acrylic installed in different heights. The experimental unit that operated in steady state allowed the verification of the total flow and, consequently, the determination of actual flow in each passage branched. The few theoretical works in this area do not prove the theory experimentally, does not analyze the influence of physical properties and do not estimate the power of the engine. This work allowed us to compare the theoretical and experimental values with deviation of 12,5 to 20,5% being proposed after a theoretical split into steps for determining the operating point of the system. The use of this proposed sequence reduces installation costs by avoiding control loops, and operating costs by reducing the energy consumed in industrial systems / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química

Orientador: Ana Ines Borri Genovez / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-04T10:56:38Z (GMT). No. of bitstreams: 1 DalfreFilho_JoseGilberto_D.pdf: 10243119 bytes, checksum: 5829e5204ff010a8a6d3e3a1d85f4916 (MD5) Previous issue date: 2005 / Resumo: O equipamento tipo jato cavitante utiliza um bocal especialmente projetado para simular o fenômeno da cavitação desgastando uma amostra em um período de tempo curto. Isso ocorre, sobretudo, devido à magnitude da velocidade. Para maior eficiência do jato cavitante é necessária uma combinação da geometria do bocal, do diâmetro do orifício e da pressão disponível. No caso das estruturas hidráulicas se verifica o efeito simultâneo do fenômeno da cavitação e do impacto de um jato de alta velocidade. O objetivo deste trabalho foi desenvolver um equipamento tipo jato cavitante para avaliar o desgaste ocasionado pela cavitação em amostras de concreto. O estudo foi realizado no Laboratório de Hidráulica e Mecânica dos Fluidos da Faculdade de Engenharia Civil. A instalação permite variar os parâmetros de ensaio, de forma a obter a máxima eficiência do equipamento e definir o comportamento da amostra. O índice de cavitação de 0,14 é adequado aos ensaios em concretos de estruturas hidráulicas. Recomenda-se uma velocidade do jato em torno de 150 m/s, a adoção de 0,05 m de distância entre o bocal e a amostra e o uso de bocal cônico de 132°, com arestas vivas. A partir dos testes realizados, sugere-se um tempo de ensaio de quatro minutos para avaliação da resistência dos materiais face à ação da cavitação. Conclui-se que o equipamento tipo jato cavitante se mostrou adequado e eficiente para avaliação do desgaste provocado pela ação da cavitação, em um tempo curto de ensaio. As características do banco de ensaio permitem que ele seja instalado em laboratório ou em campo / Abstract: The cavitating jet apparatus uses an especially projected nozzle to produce cavitation and have the advantage of induce cavitational flow with short time test. That is due, mainly, to the magnitude of velocity. In order to obtain great efficiency of the cavitating jet apparatus one has to combine the nozzle geometry, the orifice diameter and the necessary pressure. In hydraulic structures it is verified the simultaneous effect of the cavitation phenomenon and the impact of a high velocity jet. The objective of this work was to develop a cavitating jet apparatus to evaluate the erosion caused by cavitation in concrete samples. The study was carried out in the Hydraulics and Fluid Mechanics Laboratory of the Civil Engineering, Architecture and Urbanism College. The installation allows varying the tests parameters, to get the maximum efficiency of the equipment and to obtain the sample damage. A cavitation index of 0,14 showed to be a value where damage in hydraulics structures was presented. It is suggested to perform tests with a jet velocity of approximately 150 m/s, the adoption of 0,05 m of distance between the nozzle and the sample and also the use of conical 132° nozzle with sharp edges, which showed to be adequate to the laboratory experiment with concretes ordinarily used in hydraulic structures. According to the tests, it can be normalize the adoption of four minutes test for evaluation of the cavitation samples resistance. It is concluded that the cavitating jet apparatus is adequate and efficient for evaluation of erosion through cavitation action in a short time tests. The characteristics of the experimental installation allow its use either in laboratory or in field tests / Doutorado / Recursos Hidricos / Doutor em Engenharia Civil

Hydrologic and hydraulic modeling are used to assess watershed function at different spatial and temporal scales. Many tools have been developed to make these types of models more accessible to use and model results easier to interpret. One tool that makes hydrologic models more accessible in a geographic information system (GIS) is the Automated Geospatial Watershed Assessment tool (AGWA); the GIS enables the development of spatially variable model inputs and model results for a variety of applications. Two major applications of AGWA are for rangeland watershed assessments and post-wildfire rapid watershed assessments. Each of these applications have primarily utilized the Kinematic Runoff and Erosion model (KINEROS2) which is accessible in AGWA. Two new tools were developed which work within the existing AGWA/KINEROS2 framework in ArcGIS to enhance rangeland and post-wildfire watershed assessments. The Storage Characterization Tool, was developed to work with high-resolution topographic data to characterize existing stock ponds so these features can easily be incorporated into AGWA/KINEROS2 for rangeland hydrologic analysis. The second tool simulates reach scale flood inundation (the Inundation Tool) utilizing AGWA/KINEROS2 outputs and local channel properties for Hydrologic Engineering Center (HEC-2) hydraulic calculations to compute flood inundation in post-wildfire environments. Both tools have been validated using multiple datasets and desired applications were outlined so that the tools are properly used.

Abstract The understanding of flow processes is a key to evaluating treatment efficiency in constructed wetlands. This work focuses on the effects of flow paths on phosphorus (P) and nitrogen (N)retention in four treatment wetlands constructed on pristine peatlands in Finland. Particular attention was paid to water residence time, effective flow area and effective flow depth. Both an artificial tracer test and a new method based on the analysis of stable oxygen and hydrogen isotope distributions were employed. Tracer tests were used to calibrate steady-state flow models created using a groundwater modelling MODFLOW code. Furthermore, concentrations of P, Al and Fe in the peat and concentration of N in the surface water were measured. Surface water tracer distributions showed overland flow to be the dominant flow process and it was divided into a preferential flow area and dead zones. Also, active channel formation was observed during the years of the study (2002–2005). The results indicate that the hydraulic performance might deteriorate drastically within a short period of time. The active flow areas in the peatlands comprised only about 40–48% in summer, meaning that large areas with potential for nutrient removal were left unused. Flow simulations showed that a more optimal length of the distribution ditch will create a larger effective flow area and possibly could prevent channel formation. The peat P concentration was 1.8±3.9 mg g-1, and P was accumulated in the preferential flow area. The peat P concentration correlated positively with Al in the Ruka peatland treating wastewater. The results indicate that precipitation chemicals increase the P retention capacity of peatland substantially and maintain P retention at a stable level despite variable P loads. Furthermore, the results indicate that the accumulation of P to peat via adsorption and chemical precipitation is the major P removal process even after 10 years of loading. In Ruka, calculated N concentrations in surface water obtained with a first-order area model, together with regression analysis of the rate constant, were in good agreement with observed N concentrations. If a removal of 70% is to be achieved, the NH4-N loading to the peatland should be below 0.10 mg m2 d-1.

Seepage direction is crucial for understanding the critical state and development of piping erosion. A stress-controlled apparatus was designed to investigate the piping behavior of cohesionless soil under upward flow condition. The components of the new apparatus included a loading chamber, a vertical and confining loading system, an upstream water supply device, a soil-water separating system, and a water collecting system. The loading chamber provides space for a soil specimen setting and loading. The combination of a vertical and a confining loading system was designed to apply complex stresses to a soil specimen. Under the stresses, the specimen was then eroded by the gradually increasing hydraulic head supplied by the water supply system. The eroded particle and spilling water were collected and detected by the soil-water separating system and the water collecting system. A series of experiments were carried out using the new apparatus. Results demonstrated the repeatability experiments and usefulness of the apparatus. The new apparatus allowed us to investigate the piping behavior under different stress states and hydraulic gradients. With this new apparatus and experiments, we found that lower and high critical hydraulic gradients (CHGs) should be included as the criteria of piping development based on the relationship between the hydraulic gradient and the seepage response. In addition, the stress state on the CHG and the particle erosion rate played important roles in the piping development. The outer pressure on the specimen can retard the development of erosion. In contrast, the hydraulic gradient was found to be positively correlated to the erosion rate. Results also indicated that a specimen would collapse once the amount of eroded small particles exceeds the critical value of 46.5 % of the soil.

This dissertation investigates the control of the electrical energy input to a three-phase electric arc furnace (EAF). Graphite electrodes are used to convert electrical energy into heat via three-phase electric arcs. Constant arc length is desirable as it implies steady energy transfer from the graphite electrodes to the metallic charge in the furnace bath. With the charge level constantly changing, the electrodes must be able to adjust for the arc length to remain constant. In this dissertation electric arc current is used as the control variable. This is the most often used control variable in the electric arc furnace industry and implies fast adjustments of short circuits between the electrode tips and the metallic charge. The motivation behind the modelling of the electrode system for a three-phase electric arc furnace is to extend an existing EAF model developed at the University of Pretoria. The existing model investigates the control of the electric arc furnace process itself and it is assumed that the applied electrical energy input is constant. Proportional-Integral-Derivative (PID) control as well as Model-Predictive-Control (MPC) is applied to the electrode system. Time delays on the outputs of the hydraulic actuators makes it necessary to include approximations of time delays on the outputs of the linear model, which is needed for controller design. A well known general control problem is followed in this dissertation. All models are derived from first principles, and complete controller design is carried out. Most available literature lack in at least one of these fields. / Dissertation (MEng (Electronic Engineering))--University of Pretoria, 2007. / Electrical, Electronic and Computer Engineering / unrestricted

Florida is the second leading horticulture state in the United States with a total annual industry sale of over $12 Billion. Due to its competitive nature, agricultural plant production represents an extremely intensive practice with large amounts of water and fertilizer usage. Agrochemical and water management are vital for efficient functioning of any agricultural enterprise, and the subsequent nutrient loading from such agricultural practices has been a concern for environmentalists. A thorough understanding of the agrochemical and the soil amendments used in these agricultural systems is of special interest as contamination of soils can cause surface and groundwater pollution leading to ecosystem toxicity. The presence of fragile ecosystems such as the Everglades, Biscayne Bay and Big Cypress near enterprises that use such agricultural systems makes the whole issue even more imminent. Although significant research has been conducted with soils and soil mix, there is no acceptable method for determining the hydraulic properties of mixtures that have been subjected to organic and inorganic soil amendments. Hydro-physical characterization of such mixtures can facilitate the understanding of water retention and permeation characteristics of the commonly used mix which can further allow modeling of soil water interactions. The objective of this study was to characterize some of the locally and commercially available plant growth mixtures for their hydro-physical properties and develop mathematical models to correlate these acquired basic properties to the hydraulic conductivity of the mixture. The objective was also to model the response patterns of soil amendments present in those mixtures to different water and fertilizer use scenarios using the characterized hydro-physical properties with the help of Everglades-Agro-Hydrology Model. The presence of organic amendments helps the mixtures retain more water while the inorganic amendments tend to adsorb more nutrients due to their high surface area. The results of these types of characterization can provide a scientific basis for understanding the non-point source water pollution from horticulture production systems and assist in the development of the best management practices for the operation of environmentally sustainable agricultural enterprise

Condition monitoring of hydraulic systems is an area that has grown substantially in the last few decades. This thesis presents a scheme that automatically generates the fault symptoms by on-line processing of raw sensor data from a real test rig. The main purposes of implementing condition monitoring in hydraulic systems are to increase productivity, decrease maintenance costs and increase safety. Since such systems are widely used in industry and becoming more complex in function, reliability of the systems must be supported by an efficient monitoring and maintenance scheme. This work proposes an accurate state space model together with a novel model-based fault diagnosis methodology. The test rig has been fabricated in the Process Automation and Robotics Laboratory at UBC. First, a state space model of the system is derived. The parameters of the model are obtained through either experiments or direct measurements and manufacturer specifications. To validate the model, the simulated and measured states are compared. The results show that under normal operating conditions the simulation program and real system produce similar state trajectories. For the validated model, a condition monitoring scheme based on the Unscented Kalman Filter (UKF) is developed. In simulations, both measurement and process noises are considered. The results show that the algorithm estimates the iii system states with acceptable residual errors. Therefore, the structure is verified to be employed as the fault diagnosis scheme. Five types of faults are investigated in this thesis: loss of load, dynamic friction load, the internal leakage between the two hydraulic cylinder chambers, and the external leakage at either side of the actuator. Also, for each leakage scenario, three levels of leakage are investigated in the tests. The developed UKF-based fault monitoring scheme is tested on the practical system while different fault scenarios are singly introduced to the system. A sinusoidal reference signal is used for the actuator displacement. To diagnose the occurred fault in real time, three criteria, namely residual moving average of the errors, chamber pressures, and actuator characteristics, are considered. Based on the presented experimental results and discussions, the proposed scheme can accurately diagnose the occurred faults. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Measurement of the volumetric flow rate of each of the flowing components in multiphase flow is often required and this is particularly true in Production Logging applications. Thus, an increasing level of interest has been shown in making flow rate measurements in multiphase flow. A new generation of tomographic instrument, which enables measurement of the instantaneous local velocity vector and the instantaneous local volume fraction of the dispersed phase, is now being introduced. However validation and calibration of such instruments is necessary. This thesis describes the development of a miniaturised local four-sensor conductivity probe capable of acquiring measurements of the local velocity vector, gas volume fraction and the local axial gas velocity in the bubbly gas-liquid flows. Experimental techniques in which the probe was used to obtain the local gas velocity vector and the local gas volume fraction in a bubbly gas-liquid flow are also described. High speed cameras are introduced for the measurement of the reference velocity of the bubbles. The camera images are also used to plot the trajectory of any bubble that hits all four-sensor of the probe. Extensive experimental results showing the distribution of the local gas volume fraction and the local axial, azimuthal and the radial bubble velocity components in vertical and swirling gas-liquid flows are presented.