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Estudo do desempenho de um precipitador eletrostático operando na captura de partículas submicrométricas e nanométricas
(Universidade Federal de São Carlos, 2005-05-24) Falaguasta, Maria Carolina Ribeiro; Coury, José Renato
The removal of submicron particles from gaseous streams is becoming an increasingly important operation, both in industrial (nanotechnology) as well as in occupational (inhalation of particula te matter) applications. Among the equipments commonly employed for the removal of particula tes of the gaseous stream, the electrostatic precipitator, ESP, is the one capable of removing particles of such size with high efficiency. Furthermore, it has other advantages as the low pressure drop and the flexibility of working at higher temperatures. Therefore, the objective of this research was to evaluate the influence of operational and design parameters in the efficiency of particle removal of a plate-wire ESP operating in the removal of submicron particles. The precipitator was built in acrylic, with copper plates as collecting electrodes and stainless steel wires as discharge electrodes. The study was divided in two stages: the first studied the collection of PM2.5 (high risk particle matter), using alumina, with median diameter of 0.6 mm and maximum diameter of 2.5 mm as test powder, while the stage 2 focused the nanometric range, utilizing particles of sodium chloride, with diameters between 8 and 100 nm. In stage 1, the project parameters analyzed were duct length (L), diameter of the discharge electrodes (2r) and spacing between them (2c); the operational variables were the electric field (E) and the air velocity (v). Each variable was evaluated in two levels, whose values were Lne = 15 and 30 cm; 2r = 0.045 and 0.025 cm; 2c = 4 and 2 cm; E = 5 and 8 kV/cm and, finally, v = 0.5 and 1.0 m/s. The process performance was evaluated through the analysis of the global efficiency of removal of the particula te matter, obtained through isokinetic sampling. In stage 2, the project parameter analyzed were the duct length (Lne), the ratio s/2c and the distance between the collection plates (2s) and the operational variables were the air velocity (v) and current density (j). Each operation variable was evaluated in three levels, whose values were v = 0.125, 0.25 and 0.50 m/s and j = 1.8, 2.8 and 3.8 mA/m2. The project parameters were studied in two leve ls, Lne = 15 and 30 cm and 2s = 0.04 and 0.06 m. The process performance was evaluated through the analysis of the removal efficiency of the particulates obtained by particle counting, with the use of the Condensation Particle Counter 3007, from TSI. It was observed that the precipitator possesses high collection efficiency, even in the nanometric size range, were efficiencies larger than 99% were obtained, depending on the used configuration. As expected, the increase in air velocity, as well as the decrease of the collecting plate length and of the generated current caused a decrease in the efficiency. Conversely, larger spacing between plates resulted in an increment in the efficiency, phenomenon also observed by some other researchers for larger particles. The ratio s/2c did not show a clear tendency in particle removal. When compared to models from the literature, the one that offered the better adjustment to the experimental data was the classic Deutsch model when used with a drag coefficient given by a modified version of the Li and Wang (2003a e b) equation.
Análise comparativa dos mecanismos de governança das redes agroindustriais avícolas da macrorregião de Ribeirão Preto SP e de Santa Catarina.
(Universidade Federal de São Carlos, 2005-05-24) Pinotti, Raquel Nakazato; Paulillo, Luiz Fernando de Oriani e; https://lattes.cnpq.br/9919942357089937
This text has as objective main to carry through a comparative analysis it enters the power network of being poltry of the macroregion of Ribeirão Preto of the state of São Paulo and of the state of Santa Catarina, taking for base the individual and collective action of the actors and its main dynamic resources of power (constitutional, technological, financial, legal politicians and organizacionais ). From the studies of the characteristics of the actors of each network (number of participants; function, types of relation, structure and distribution of being able), were possible to verify that the catarinense poltry network presents more dynamic resources of power, greater coordination and harmony between its actors. The catarinense network has presence of formal relations of production, significant presence of dynamic resources of power and the legitimacy of the great industrial firms in the coordination of the system of integration and the network, while that the São Paulo network presents sufficiently distinct configuration: more types of actors (the independent agricultural producers, the intermediate and the corrector of chicken), low representation of its actors, informal relations of production and minor presence of dynamic resources power. In this context, it was possible to conclude that the networks possess trajectories of dependence (path dependence) well distinct, that lead to the structure of the distribution of dynamic resources of power presented.
C-CORE : uma Ferramenta de programação para construção e reuso de componentes
(Universidade Federal de São Carlos, 2005-05-24) Souza Neto, Raphael Marcilio de; Prado, Antonio Francisco do; https://lattes.cnpq.br/2668568143800755; https://lattes.cnpq.br/5956634284343253
The Software Development contains several activities that are not always supported by tools that aid the Software Engineer and automate great part of his activities. Different researches have been accomplished and many resources have been spent aiming to construct tools that support the Software Development Process. Among these tools, stand out those that support project and implementation activities, and that are integrated with tools that support other activities of the software construction process. With those tools, it can be obtained a larger consistence of the results that are produced along the whole software development cycle. Another important point of the development process is related to obtain a software with better quality and less cost. One of the areas that is highlighted in the software production with quality and less cost, is those that researches the software components reuse. Thus, the Software Component Oriented Programming Tools integrated with modeling tools that aim mainly to improve the software productivity based on reuse is standing out. Motivated by these ideas, this work presents a tool denominated C-CORE, that supports the project and implementation of components and their applications integrated with other modeling tool, denominated MVCASE.