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The fluid dynamics of a downer fluidised bed using a cluster-based approach (CBA)
Fluidodinámica de un lecho fluidizado Downer usando aproximación CBA
DOI:
https://doi.org/10.15446/ing.investig.v30n1.15204Keywords:
downer reactor, fluidisation, numeric simulation (en)Downer, fluidización, simulación numérica (es)
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The fluid dynamics of a downer reactor were numerically resolved by adapting a mathematical conservation model. The mathematical model was based on the solid and fluid properties and physical characteristics using a cluster-based approach (CBA). Comparing the numerical results to the experimental data found in the literature indicated that the mathematical model could satisfactorily predict the experimental data. The mathematical simulation determined that there were three fluid dynamic areas in the downer reactor which were characterised by accelerated, slowed -down and fully-developed flow. The fully developed flow area in the downer decreased with increased gas surface speed keeping solid flux constant.
En este trabajo se estudió el comportamiento fluidodinámico de un reactor de lecho fluidizado tipo Downer, adaptando un modelo matemático de conservación. El modelo matemático está basado en las propiedades y características físicas del sólido y del fluido, utilizando una aproximación CBA (Cluster-Based Approach). La comparación entre los resultados numéricos del modelo y los datos experimentales encontrados en la literatura indicaron que el modelo puede predecir los datos experimentales satisfactoriamente. La simulación matemática estableció que dentro del reactor Downer existen tres regiones fluidodinámicas activas, caracterizadas por un flujo acelerado, desacelerado y completamente desarrollado, y que esta última región disminuye a medida que se incrementa la velocidad superficial del gas manteniendo el flujo de sólidos por unidad de área constante.
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Copyright (c) 2010 Germán González Silva, Antônio Carlos Luz Lisboa, Héctor José Ciro Velasquéz
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