Estudo experimental e de simulação CFD da fluidodinâmica de um leito de jorro de médio porte com defletor de fonte

Abstract

The spouted bed is equipment that can be applied in various operations and areas of study. This is possible due to its characteristic fluid-dynamic behavior, which guarantees a high degree of contact between the solid-gas phases, high mixing rates and heat and mass transfer. Despite all these advantages, the equipment presents certain obstacles to its use on an industrial scale. Therefore, proposals for the insertion of internal accessories and variations in the configuration of the spouted bed have been studied. The source confiner is an accessory that helps stabilize the flow and has recently been successfully applied. In view of the above, in the present work we intend to investigate experimentally and through numerical simulations the influence of the insertion of a device, called source deflector, on the characteristics of the air-particle flow inside a medium-port spout bed. A geometry for the source deflector was proposed and adapted to the bed used. The particulate material selected for the experiments was dry mother seeds, which had physical characterization carried out regarding the following properties: average diameter, sphericity and apparent density. The porous medium was characterized regarding bulk density, bulk porosity, humidity and reserve angle. The main characteristic of breast sensations is its low apparent density (610 kg/m 3 ) and the formation of a bed of particles with high porosity (0.73). The experimental characteristic fluid dynamic curves were obtained for the equipment without deflector and with the deflector positioned at a height of 15 cm in relation to the conical base of the bed. It was noticed that the presence of the deflector practically did not interfere with the minimum spout velocity obtained and also on the maximum experimental pressure drop. The experiments also indicated that the deflector makes it possible to use the jetting operation for light materials that normally have their elutriation favored in the bed. The numerical results made it possible to visualize the changes in the distribution of particles in the spouted bed when the deflector was inserted. In this way, this study made it possible to design a new internal device and evaluate its influence on the fluid dynamics of spouted bed flow.