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RESUMENEn este trabajo se analizan las componentes de velocidad radial (u), azimutal (v), los flujos volumétricos primario (Qp), secundario (Qs) y el coeficiente de par (Cm), que se generan en el interior de un cilindro cerrado que tiene la tapa giratoria y el fondo y envolvente sin movimiento. Los resultados se presentan mediante gráficas en las que se analizan dichas propiedades, en régimen laminar, para un número de Reynolds de 3x104 y para un factor de forma (alto/radio) del recipiente de 1.0, 1.25, 1.5, 1.75 y 2.0. Tomando como referencia la relación geométrica de 1.0 y comparándolo con los otros factores de forma, se encontró que: la componente de velocidad radial (u) se incrementó en su valor máximo positivo en un 14.02 %; la componente de velocidad tangencial (v) mantuvo los mismos valores máximos en todas las relaciones geométricas; el flujo volumétrico primario aumentó en un 193.25 %; el flujo volumétrico secundario se incrementó en un 236.48 %; y el coeficiente de par aumentó en un 94.41 %. Los resultados anteriores revelan que al modificar la relación de esbeltez del sistema las propiedades cinemáticas estudiadas no siguen un patrón de variación homogéneo y que dependerá del interés que se tenga en alguna de ellas para analizar su comportamiento.Palabras claves: Flujo rotatorio; relación de esbeltez; flujo volumétrico; coeficiente de par. ABSTRACTIn this work we analyse the components of the radial velocity (u), azimuthal (v), primary and secondary volumetric flows, (Qp), and (Qs), and the torque coefficient (Cm), all of which are produced inside a closed cylinder which has a rotary lid and the bottom and wraparound surface are static. The results are graphically presented, considering a Reynolds number laminar of 3x10 4 and for container form factors (height/radius) of 1.0, 1.25, 1.5, 1.75, and 2.0. Starting from a geometric ratio of 1.0 and comparing it to the rest of form factors, it was observed that the radial velocity component (u) increased its maximum positive value in a 14.02 %; the tangential velocity component kept the same maximum values in all the geometric ratios; the primary volumetric flow increased by 193.25 %; the secondary volumetric flow increased by 236.48 %; and the torque coefficient also increased by 94.41 %. These results imply that in modifying the slenderness ratio of the system, the studied kinematic properties do not follow an homogeneous variation pattern and depending on the concern of each of them, its behaviour should be analysed in detail.

In this work the mathematical modeling of the drying process of plantain (Musa paradisiaca), with hot air in a tunnel under forced flow conditions is presented. The temperature of air was 60 °C at a velocity of 3.0 m/s. The geometric form of the product cuts was considered: round slices of 4.0 cm of diameter and 1.5 mm of thickness. The drying time for the slices was 300 min. The numerical model obtained for the kinetics of drying was the logarithmic one. Organoleptic properties were used to evaluate the quality of the productor final.

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The phytoextraction potential of water hyacinth (Eichhornia crassipes) in the treatment of a representative sample of water of Madín Dam, contaminated with 24.45 mg/L of aluminum (Al) and 5.10 mg/L iron (Fe) was evaluated. Two 60 days experiments were performed, one using young and adult plants and the other with young ones, extracted and substituted every 15 days. The percentage of maximum removal observed in the hyacinth exposed for 60 continuous days was the one of young hyacinths, namely 72%. Besides, those hyacinths extracted every 15 days extracted about 86% of the metals in contaminated water. Eichhornia crassipes turned to be a Al and Fe tolerant species, but not capable of transporting those metals from the roots to the leaves. However, its harvest implies the removal of the whole specimen and therefore the complete extraction of the plant. This indicates that a post-treatment of the extracted hyacinth as a hazardous material would be required, due to its high content of heavy metals.