Dissertações em Engenharia de Infraestrutura e Desenvolvimento Energético (Mestrado) - PPGINDE/NDAE/Tucuruí

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/9401

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Agora exibindo 1 - 12 de 12

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Análise do aproveitamento energético em redes de distribuição de água com a utilização de bombas como turbina (BFT)
(Universidade Federal do Pará, 2022-03-31) SILVA, Victor Renan Barbosa da; ISHIHARA, Júnior Hiroyuki; http://lattes.cnpq.br/3498874642887006; https://orcid.org/0000-0002-0081-7913
Climate change has intensified research related to the production of renewable energies around the world. In this sense, the present study intends to contribute to the analysis of the use of Pumps Functioning as Turbine (PAT) to replace Pressure Reducing Valves (PRV), aiming both at the control of pressure in water distribution networks, as well as , consequently, its use for energy generation. The installed PAT must be able to operate under different flow rates due to fluctuations in the water consumption rate, which makes it difficult to select the appropriate pump, therefore, the selection process of PATs to replace PRVs was optimized by combining two selection methods and PAT prediction, Williams (1995) the first method was used to select the appropriate PAT according to height and flow data available in the network, then the method of Rossi et al. (2019) was used to evaluate the characteristic curves of the pump as a turbine, with particular attention to out-of-design operating conditions. Two simulations were performed for the optimization process, considering the PAT with constant speed, applied to a real network that was divided into 3 district measurement areas (DMA). In the first simulation a PAT was added to the network to replace a PRV located at (DMA 3), in the second simulation two PATs were added to the network (DMA 3) to replace the PRVs. The results show, in simulation 2, that the pressure control was better, in addition to the recovery of electrical energy, which was 190.96 kWh/day or 69.70 MWh/year, corresponding to a reduction of 41.74 tons of CO2 not emitted. Thus, the energy recovery was 267% higher compared to simulation 1. In addition, the pressure control also presented satisfactory results, staying within the established standards. Therefore, the combination of Williams' (1995) and Rossi et al. (2019), simplified the work of BFT selection and prediction with significant results and it was possible to conclude that BFTs working at peak consumption hours can adjust the required standard pressure and, in the rest, PRVs can regulate the pressure. In this case, in addition to controlling the pressure continuously, significant renewable energy can be recovered from the WDN
Acesso aberto (Open Access)
Análise experimental da resistência à punção em lajes lisas com substituição de agregados graúdos naturais por reciclados de concreto
(Universidade Federal do Pará, 2022-05-12) RIBEIRO JUNIOR, Jayron Alves; FERREIRA, Maurício de Pina; http://lattes.cnpq.br/4242041552985485; https://orcid.org/0000-0001-8905-9479
The popularization of the use of recycled concrete aggregates has increased due to socioeconomic aspects, but above all, as sustainability is being pursued and, in this context, some international standards have been published to facilitate and standardize the use of this material. Despite the constant evolution of studies on punching shear, there is a need for national and international regulatory adjustments in relation to the use of recycled concrete aggregates in flat reinforced concrete slabs. Two reasons explain the slight influence of the incorporation of recycled aggregates on the punching shear resistance of concrete slabs: lower mechanical strength and better bond between the cement paste and the recycled concrete aggregate due to the higher cement content, porosity, and roughness, when compared with natural aggregate. Thus, the punching shear strength is influenced by these properties of the aggregates along the shear plane of the cracks, the two effects offset each other, leading to a similar punching shear strength. This research carried out the experimental test of 6 flat slabs of reinforced concrete without shear reinforcement subjected to symmetrical loading, containing variations in the rate of flexural combat reinforcement (0.7% and 1.4%) and replacement rate of natural aggregate by recycled concrete aggregate (0%, 30% and 100%). The study evaluated the influence of these variables on the punching shear resistant capacity and analyzed the upper limits of resistance. The slabs were octagonal with 2500 mm of distance between parallel faces, sides of 1030 mm and thickness of 210 mm, molded with concrete with fck of 25 MPa and supported on columns of 300 mm of side. The standards used as a parameter for estimating resistant capacity were NBR 6118:2014, ACI 318:2019 and Eurocode 2:2004. The experimental results showed that the slabs with ARCO showed a maximum reduction of 6 % in the punching shear resistance when compared to the slabs with conventional coarse aggregates. The reinforcement rate was able to increase the cracking load at the service limit state (ELS) and the recycled concrete aggregate had little influence on the opening of cracks in the slabs with the highest rate of flexural reinforcement.
Acesso aberto (Open Access)
Análise experimental de consolos curtos de concreto armado com fibras e variação da armadura de costura
(Universidade Federal do Pará, 2023-11-23) QUEIROZ, Daniel Pessanha de; LIMA NETO, Aarão Ferreira; http://lattes.cnpq.br/0287664572311345; https://orcid.org/0000-0002-5911-1368
Short armoured concrete consoles are pre-molded structural elements, arranged in balance, which function as a load support. This work aims to analyze experimentally the behavior of short consoles of armed concrete with variation of sewing armour area and application of a fixed content for steel fibers, polyethylene and polypropylene. Ten symmetrical specimens were analyzed, where four speciments did not contain sewing armor and possessed respectively the steel fibers (CA), polyethylene (CPE), polypropylene (CPP) and a fiber-free (CSF). Four specimens with six sewing armor Ø6.3 mm and used steel fibres respectively (C6Ø6.3A), polyethylene (C6Ø6.3PE), polypropylene (C6Ø6.3PP) and a fiber-free (C6Ø6.3SF). One specimen with six armor Ø5.0 mm seam and polyethylene fiber (C6Ø5.0PE). One specimen with eight armor Ø5.0 mm seam with polyethylene fiber (C8Ø5.0PE). They are presented, analyzed and discussed the results of: deformations of concrete and main traction armor and sewing; breaking modes; cracking maps and patterns; end resistance and loads of consoles; as well as the efficiency factors of biela, subsequently these topics above should be compared with those obtained by Abrantes (2019) and with what advocates the regulatory standards ABNT NBR 9062 (2017), NBR 6118 (2023), EUROCODE 2 (2010) and ACI 318 (2014). It is concluded that they have achieved better results compounds that received the addition of fibers. In terms of compression, traction and modulus of elasticity, comparing the matrix without and with fibres, polyethylene was 15%, steel 18% and polypropylene 21% more efficient, respectively. It can be seen that for each test a different fibre performed better. In general, C8Ø5.0PE achieved good results in all analyses, despite not being the specimen with the largest seam reinforcement area. This result is justified by the arrangement of the reinforcement inside the concrete, as well as the presence of the polyethylene fibre.
Acesso aberto (Open Access)
Análise experimental de consolos curtos de concreto com armaduras continuas e descontinuas
(Universidade Federal do Pará, 2019-09-30) ABRANTES, Jedson Henryque Corrêa; TEIXEIRA, Marcelo Rassy; http://lattes.cnpq.br/8912916360456192
Short consoles, as well as some reinforced concrete elements, have discontinuity regions (D regions), where Bernoulli's hypotheses should not be taken into account, since stress flows do not distribute linearly along the cross section. In order to correct the disturbances caused by this flow in specific areas, it is necessary to look for alternatives of calculation through equations idealized by empirical perceptions of researchers, or by means of the Strut-and-Tie Method. In this context and after theoretical and experimental observations of consoles, it was concluded that it is formed in this structure a bottle-shaped strut, and although there is a considerable database in this regard, there is no consensus in the literature and among current codes that relate between continuous reinforcement rates, failure mode and strut efficiency factors . Thus, an experimental study was carried out to evaluate the contribution of three types of fibers (discontinuous reinforcement), polypropylene, polyethylene and steel, which were added to the concrete in three different contents for each one. The results showed that in general there were similar behaviors for the concrete readings, and the opposite when analyzing the continuous reinforcement that suffered tensile stresses (Tie). For the elements with metallic fibers the resistance gain in relation to the reference specimens was noticed for the part that received higher fiber content. For synthetic fibers, polypropylene fiber had better gain in the specimen with second best fiber volume, and for polyethylene was registered for the lowest percentage. These consoles also presented better ductile behavior among all the test elements that did not receive horizontal stirrups. Regarding the results compared to the specimen with continuous reinforcement only the one with polyethylene fiber achieved superior result. Regarding the strut efficiency factors, the method presented results against and in favor of safety, while with respect to the shear strength the codes estimates had very favorable results. Therefore, MBT is a very suitable method for design that presents efficiency and safety through structures that present stress and deformation disturbances.
Acesso aberto (Open Access)
Análise experimental do desempenho à flexão de vigas de concreto armado reforçadas com laminado de fibra de carbono com variação da taxa de armadura existente e do mecanismo de ancoragem
(Universidade Federal do Pará, 2025-06-17) LEÃO JÚNIOR, Paulo Sérgio Barreiros de; LIMA NETO, Aarão Ferreira; http://lattes.cnpq.br/0287664572311345; https://orcid.org/0000-0002-5911-1368
The strengthening of existing reinforced concrete structures with Fiber-Reinforced Polymers (FRP), using techniques such as Externally Bonded Reinforcement and Near-Surface Mounted, is common in practical applications, especially when using Carbon FRP (CFRP). However, in strengthening scenarios that require higher load capacities, these methods may be less effective due to premature debonding failure, highlighting the importance of anchorage systems to improve reinforcement efficiency. There is limited information in the literature regarding the influence of steel reinforcement ratio on the behavior of beams strengthened with anchorage systems. Therefore, this study experimentally investigates the flexural performance of reinforced concrete T-beams strengthened with CFRP, considering two steel ratios (0.44% and 1.12%) and two anchorage systems. Flexural tests were conducted on six T-section beams (2200 mm length, 280 mm height, 180 mm web width, and 80 mm thick by 350 mm wide flange). Each beam had 21 stirrups made of 12.5 mm bars spaced at 100 mm. For each steel ratio, one beam was unstrengthened (reference), and two were strengthened using either a friction-based mechanical anchorage (Hybrid Bonded – HB) or an anchorage system using bonded CFRP strips (FT). Strengthening was more effective in beams with the lower steel ratio, with strength increases of 58% for HB and 11% for FT. For the higher steel ratio, gains were limited to 10% for HB and none for FT. The HB system achieved a flexural capacity of 117.72 kN·m and showed better performance in intermediate displacements, with ductility increases up to 57 times at cracking and up to 100% at steel yielding. At maximum load, all strengthened beams showed reduced ductility. In the HB system, ductility loss increased with steel ratio, from 25% in the less reinforced beam to 49% in the more reinforced one. In the FT system, the trend was reversed, with a 66% loss for the lower steel ratio and 24% for the higher. Failure modes were governed by laminate slip in HB and cover delamination in FT.
Acesso aberto (Open Access)
Avaliação de modelo de elemento de pá aplicado a turbinas eólicas com difusores através de análise CFD
(Universidade Federal do Pará, 2023-05-30) BEZERRA, Waldson Melo; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
The diffuser effect on free flow turbines shows a possibility of reaching a power coefficient greater than that of a classic turbine, exceeding the Betz limit. The present work evaluated the effect of an Eppler 423 profile diffuser coupled in a horizontal axis wind turbine with a 4-bladed rotor NACA 65(3) 618 profile. Using computational fluid mechanics (CFD, Computational Fluid Dynamics), numerical simulations were performed allowing to obtains more information about the fluid flow and the increase in extracted power for configurations with and without diffuser for the velocity of 7 m/s. Considering the dimensions of the test section, the results obtained in the CFD analyses were validated through experimental results, in which the rotor and diffuser assembly were confined in a wind tunnel. It was observed that coupling the diffuser to the turbine considerably increased the fluid velocity, providing a 37% increase in the initial velocity of the flow. Showed an increase in the power coefficient in the order of 45,45% with the use of the diffuser, for the same flow velocity, 7 m/s. Thus, through the results obtained numerically in this work, it was possible to obtain reliable data for the evaluation of a specified Blade Element Momentum (BEM) model applied to diffuser-augmented wind turbines, which is employed to analyze the same turbine rotor and diffuser designs. Despite the good results of the BEM model, the present study indicates possible improvements for the consistency of the modeling.
Acesso aberto (Open Access)
Critério do coeficiente de pressão mínimo aplicado ao dimensionamento de bombas axiais: caso de estudo para um túnel de água circulante
(Universidade Federal do Pará, 2022-12-15) RAMALHO, Rodolfo Vitorino Correia; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
An analysis of the pressure coefficient on the suction side of blades is presented as a design criterium for axial-flow pumps. A CFD model is developed and validated from experimental tests available in the literature. The model uses the finite volume method through the commercial software Ansys CFX. In the criterion application step, the X-Foil software is used to determine the lift and drag coefficients of the blade profiles. A case study is presented for the dimensioning of axial-flow pumps for a large recirculation tunnel, to be used for testing vessels, naval structures and hydrokinetic turbines. Special attention is given to pump cavitation conditions. The criterion of the minimum pressure coefficient is then evaluated by the CFD model, showing good performance for the pump.
Acesso aberto (Open Access)
Efeito da taxa de armadura existente e do sistema de ancoragem na resistência à flexão de consolos curtos de concreto armado reforçados com laminados de PRFC
(Universidade Federal do Pará, 2025-06-13) LIMA, Layse Rafaele Furtado; FERREIRA, Maurício de Pina; http://lattes.cnpq.br/4242041552985485; https://orcid.org/0000-0001-8905-9479
Short corbels are elements used in bridges and buildings to support beams, stringers or concentrated loads of great intensity, and are characterized by having a span-to-height ratio of less than one. Over the course of their useful life, these structures can fail to meet basic safety requirements for reasons such as design error, material degradation, overload or change in use, requiring reinforcement techniques that can be applied quickly and efficiently. With this in mind, this work seeks to experimentally analyze short reinforced concrete beams reinforced externally in bending with Carbon Fiber Reinforced Polymer (CFRP) laminates. To this end, six specimens were analyzed, three with a 0.18% flexural reinforcement rate and three with a 0.47% rate. All the models have the same geometry, with the presence of horizontal and vertical stirrups. The reinforcement was positioned on both sides of the cantilever and anchored at the ends, checking the influence of two systems. The first anchoring system is made up of steel plates and bolts, while the second is made up of overlapping laminates, with transverse bonding in the last layer. As a result, it was possible to analyze that the reinforcement proved to be efficient in terms of increased resistance, which ranged from 14,5% to 50,3%, with the hybrid anchorage standing out as having the highest loading value.
Acesso aberto (Open Access)
Placas cimentícias produzidas com a incorporação de pérolas de poliestireno expandido (EPS)
(Universidade Federal do Pará, 2020-09-01) SILVA, Max Weverton Moreira da; CORDEIRO, Luciana de Nazaré Pinheiro; http://lattes.cnpq.br/9126233381230999; https://orcid.org/0000-0001-7931-4042
The Internal and External Vertical Painel Systems are the parts of the residential building that limit it vertically and delimit its environments, such as facades and walls or internal partitions. The use of seals with lower density than masonry provides a reduction in the mass of this subsystem, reducing the demand for aggregates and binders, in addition to reducing the load on the structure, which allows for optimization of its design. The objective of this work is to verify the viability of the production of cementitious slabs with the incorporation of expanded polystyrene (EPS) beads for application in internal vertical sealing elements. For this, mortars with a 1: 3 line (cement: sand) were produced, with levels of incorporation of expanded polystyrene of 0%, 10%, 20% and 30% in relation to the total volume of materials. Mortars were characterized in the fresh state, through the determination of mass density and consistency index, and in the hardened state, for knowledge of the density properties in the hardened state, resistance to compression and traction, and modulus of elasticity. After knowing the characteristics of the mortars, cementitious slabs were produced, reproducing the same trace in the specimens. The plates were tested for bulk density, water absorption, water permeability and flexural strength. The results of this work demonstrated that the cementitious slabs with the incorporation of up to 20% of EPS present technical characteristics for application in internal vertical sealing systems.
Acesso aberto (Open Access)
Procedimentos experimentais para avaliação da emissão de poeira em manuseio de minério
(Universidade Federal do Pará, 2018-11-29) SANTOS JUNIOR, Ronaldo Menezes dos; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
The generation of dust during the handling and transportation of bulk causes a series of problems, such as the erected air and loss of valuable material. Due to the risk associated with inhalation of dust, several control mechanisms have been adopted. The use of water is a viable option to inhibit the generation of dust, although the use of chemical suppressants is in some cases more appropriate. However, standards and methods for characterizing the generation of particulates are not very consolidated in the literature, for the proper selection of the control mechanism. Therefore, this study aimed to develop test methodologies to evaluate the emission of minerals particulate. The emission of particulate during transport was evaluated in a test bench developed by adapting an existing wind tunnel, using a wagon model and air speeds of 40 km/h and 70 km/h, for different iron ore moisture values. Results show that the increase in flow speed increases the loss of material mass contained inside the wagon model and the increase in material moisture significantly reduces the loss of mass, being enhanced with the use of dust suppressants applied to the material surface. To simulate material handling, a bench was developed using the dust tower technique concept, which allows dust generation tests during material discharge. In the results obtained, it is also verified that the increase in material moisture significantly reduces the emission of particulates, being more evident for materials that have a higher percentage of fines. The influence of suppressants was also evaluated, and among the tested reagents Fe2(SO4)3 showed the best result for the pellet feed milled, greatly reducing the emission of particulates in relation to the use of water only. For pellets, Ca(OH)2 showed the best results without curing time and CaCl2 for the condition with curing time of 2 hours. Therefore, the results show that the benches and experimental procedures developed, presented satisfactory and coherent results, which are reliable for the characterization of the emission of particulates from different materials.
Acesso aberto (Open Access)
Protótipo para análise técnico-econômica de bombas funcionando como turbinas em redes de distribuição de água
(Universidade Federal do Pará, 2025-02-27) VIANA, Ingrid Luna Baia; SOUZA, Davi Edson Sales e; http://lattes.cnpq.br/6130270007673176; HTTPS://ORCID.ORG/0000-0001-9632-5667; ISHIHARA, Júnior Hiroyuki; http://lattes.cnpq.br/3498874642887006; https://orcid.org/0000-0002-0081-7913
The growing need for sustainable solutions in water distribution networks requires technologies that optimize energy efficiency and reduce operating costs. However, choosing the best alternative for implementing Pumps Operating as Turbines (BFTs) is challenging due to the multiple technical and economic criteria involved. Therefore, this study proposes a decision support model, employing multicriteria techniques and computer programming to assist in selecting the most viable alternative within different scenarios. The analysis focuses on the technical-economic feasibility of BFTs in Water Distribution Networks (RDAs), using the TOPSIS method, where data will be evaluated and classified by similarity to ideal conditions. Implemented in Python, the system ensures calculation accuracy, with a graphical interface called FliessEnergy, hosted by Vercel, with a responsive and scalable layout, providing an optimized user experience. Practical application with real RDA data demonstrated its effectiveness in prioritizing the most advantageous alternatives. The results indicated that Scenario 1 presented the best configuration for implementing BFTs, while Scenario 5 was the least favorable alternative. This classification of alternatives helps managers make decisions, taking into account both the proximity to the best conditions and the distance from the worst. To assess the reliability and consistency of the codes, PyTOPS, free software that allows several simulations with changes in the weights of the criteria, was used. A total of 500 simulations were performed, resulting in reduced variability between the scenarios, which reinforces the robustness of the model and its ability to generate consistent classifications even with small changes in the parameters. The model proved consistent and reliable, offering a useful instrument for evaluating the implementation of BFTs in RDAs. It is expected that, with future improvements and integration of databases, this solution can contribute significantly to strategic decisions in the sanitation sector in Brazil.
Acesso aberto (Open Access)
Viabilidade ambiental do tratamento do efluente industrial do dendê e uso na produção de biogás e biofertilizante
(Universidade Federal do Pará, 2024-03-28) GOMES, Emanuelle Regina Araújo; ISHIHARA, Júnior Hiroyuki; http://lattes.cnpq.br/3498874642887006; https://orcid.org/0000-0002-0081-7913
The effluents generated in the agro-industrial sector are produced in large quantities, especially those from the processing of a product for commercial use, as is the case with palm oil. In the search for alternatives for treatment and/or reuse, oil palm agro-industrial effluent can be used to produce bio-input and biofuel. The aim of this dissertation is to assess the feasibility of treating industrial oil palm effluent and using it to produce biogas and biofertilizer. The work methodology consisted of manufacturing 10 benchtop bioreactors, adapted with an automatic control system, which allowed quantification of pressure, temperature and methane concentration measurements through sensors, enabling treatment through the anaerobic digestion system of effluents. . For treatment, the effluent was inoculated with one of the solid materials resulting from the processing stages (palm oil sludge), and a physical-chemical analysis of the parameters was carried out. Finally, the system made it possible to quantify biogas production and characterize the biofertilizer generated in the system. The data analysis presented demonstrates that the POME treatment, combined with the inoculum, promotes better results for the physicochemical parameters analyzed in the research, given that the best conditions occurred for the 30% inoculum range, that is. 700 ml of effluent + 300 ml of inoculum, showing the environmental viability of the treatment. With regard to the production of biogas and biofertilizer, the indicators of temperature (20 to 45oC), pressure (1 atm) and daily methane gas production of between 0.26 and 0.44 ml in the anaerobic digestion system showed good operating conditions in the system, making their production feasible through the use of oil palm agro-industrial effluent, allowing an environmentally appropriate possibility for the waste, from the point of view of the production chain, the environment and the economy.

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