Programa de Pós-Graduação em Engenharia de Infraestrutura e Desenvolvimento Energético - PPGINDE/NDAE/Tucuruí

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/9400

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Agora exibindo 1 - 6 de 6

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)
Cálculo de ar induzido pela queda livre de materiais granulares via CFD
(Universidade Federal do Pará, 2021-12-17) LIMA, Leandro Ferreira Borba; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
The proposal of the work consists of presenting an analysis method via ANSYS-Fluent using the DDPM tool (Dense Discrete Phase Model) of the integrated Eulerian multiphase model, a better understanding of the flow of granulated material with the adjacent induced air due to the drag provided by the free-falling particles, which result in the generation and propagation of dust, avoid simulations with materials where particle density and diameters are variable. The use of this analysis tool will make it possible to improve and improve de dusting projects in industries that work with granular materials that emit dust. The simulations carried out were compared with other computational methods and practical experiments, in addition to previous theoretical formulas.
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)
Desenvolvimento de um túnel para secagem e emissão de minério em condições ambientais controladas
(Universidade Federal do Pará, 2021-12-15) SILVA, Artur José Cunha da; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
A dust emission is present in the various stages of the mineral industry, from extraction in mines to ship loading in ports. Transport in train wagons, storage in stockpiles and handling are three major sources of particulate emissions into the atmosphere. Suspended dust does not only affect the local environment, as the wind transports the particulates and brings disturbances to urban centers close to railway networks and ports. Larger particles are deposited on surfaces, outperforming visual surfaces, and smaller, unresearched particles with a size between 10 and 2.5μm are easily inhaled and lodge in lung tissue, potentially causing irritation or necrosis. Dust emission is enhanced by local atmospheric conditions, which cause the evaporation of surface moisture from the wet ore, breaking the liquid bridges that keep the particles linked together. Aiming at studying the dynamics of drying ore, a drying tunnel was designed and built, comprising a wind tunnel, cooling, heating and humidification equipment that are interconnected by a supervision and control system. The use of the bench for drying studies using sinter feed is known to be satisfactory, as the temperature remained stabilized at the setpoint during the drying time, reflecting the good calibration of the temperature PID controller. Moisture and ore mass were automatically measured using a scale and a capacitive moisture sensor positioned in the test section of the bench. The constant rate and descending rate drying curves only in the lightest weather conditions. The biggest limitations and variations were observed only in the period with decreasing drying rate, showing the influence of environmental conditions on the drying dynamics. Therefore, this work leaves as a contribution the preparation tunnel for future research and an experimental database for the calibration of numerical models and models of mathematical models for prediction prediction.
Acesso aberto (Open Access)
Determinação experimental da vazão de despoeiramento na descarga de carvão coqueificável
(Universidade Federal do Pará, 2021-02-26) CHAVES, Gabriel Guedes; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Dust control mechanisms during industrial processes are often carried out using spray nozzle methods or exhaust systems, equipped with bag filters. The following work aims to develop an experimental method to determine the volume of exhaust in different quantities of materials and different heights of material discharge. A test protocol is presented to design exhaust systems for any material, mass flow and drop height, using an experimental method in which it simulates the material drop in order to evaluate experimental dedust flow rates for an industrial ventilation system. A literature review of the current empirical models of exhaustion volume is presented. The methodology is correlated through the concentration of respirable particles measured by the measurement equipment with the exhaust flow data. The results presented are for coal, comparing existing and suggested correlations with experimental data for three different heights of fall. It is hoped, therefore, to support design engineers in the design of industrial exhaust systems, reducing the damage caused by fine particles in workers and in the population that lives near the polluting source.
Acesso aberto (Open Access)
Experimento em escala de emissão de poeira no processo de empilhamento
(Universidade Federal do Pará, 2022-03-25) CASTRO, Maycon Magalhães; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662; MACHADO, Luis Paulo Silveira; http://lattes.cnpq.br/0702289670734922; https://orcid.org/0000-0003-1587-3632
Dust emission can lead to health problems, explosion risk, material segregation and environmental pollution. Therefore, it is necessary to understand the parameters related to dust generation to improve particulate emission control techniques. Dust reduction based on spray spraying is the main method to prevent and control dust emission in ore stacking. Dust suppression techniques at conveyor belt transfer points can be subdivided into material spraying and trapping of fugitive particles. To analyze the parameters associated with dust generation during ore stacking, a scaled conveyor bench was developed for dust suppression tests via water spray. This installation is equipped with spray nozzles whose relative location on the belt can be adjusted and the speed of the conveyor can also be controlled. The spray jet is provided by a set of spray module and flow divider, allowing the variation of the system pressure and with the possibility of using suppressors, which can increase the efficiency of particle capture. Dust suppression performance is analyzed by monitoring strategic points with the highest dust emission. The results of this investigation show that dust generation increased as the drop height increased, it was observed that the region close to the pile emits a higher concentration of dust, due to the impact of the material flow on the stacking surface, in compared to the front region of the flow. The results after using the spray on the belt showed that the highest drop height (1600 mm) emitted the highest concentration of particles (3192.72 μg/m3) after spraying, on the material, the dust concentration reduced by about almost 70%, showing the efficiency of spray humidification. It was also observed that PF has a higher critical humidity than that of SF, as well as that it emits a higher concentration (1116.52 μg/m3) compared to Sinter feed (848.14 μg/m3), making it evident that by as it is a material with a smaller granulometry, the pellet feed tends to emit a higher concentration of particulates when handled.

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