Carlos H. Salinas Lira         Yerko A. Gatica Lagos         Pedro A. Pacheco Fernandoy

1 Departamento de Ingeniería Mecánica. Universidad del Bío-Bío. Av. Collao 1202. Fono: 731455/731499. Fax: 731022. Concepción, Chile. E-mail: Casali@ubiobio.cl

2 Departamento de Ingeniería Mecánica. Universidad del Bío-Bío. Av. Collao 1202. Fono: 731455/731499. Fax: 731022. Concepción, Chile. E-mail: ygatica@ubiobio.cl

3 Departamento de Mecânica. COPPE-UFRJ. Rio de Janeiro, Brasil. E-mail: ppachecofernandoy@yahoo.es

RESUMEN 

El presente trabajo muestra resultados de transporte de calor y masa (Doble) al interior de una cavidad rectangular ocasionado por un flujo convectivo forzado y natural (Mixto). El modelo matemático consta de las ecuaciones de Navier-Stokes para describir el flujo laminar de un fluido incompresible. Además es modelado el transporte de calor y masa a través de dos ecuaciones diferenciales lineales de segunda orden, incorporando en forma lineal los efectos de los gradientes de concentración y de temperaturas. El modelo matemático es resuelto numéricamente a través del Método de Volúmenes Finitos descrito en coordenadas curvilíneas y variables colocalizadas, representando los términos difusivos a través de diferencia central y usando un esquema potencial para los términos convectivos. Se muestran resultados originales de patrones de flujo: Isotermas, isoconcentraciones y números de Nusselt y de Sherwood en regiones características para el problema de flujo interno mixto con difusión de calor y masa. 

Palabras clave: Difusión, convección, cavidad rectangular, flujo laminar, simulación

ABSTRACT 

The present work shows the relationship of the transport of heat and mass (double) in a rectangular cavity caused by a  forced and natural convection. The mathematical model consists of the Navier-Stokes equations to describe the incompressible laminar flow. The transport of heat and mass are modelled through two second order no-linear differential equations, incorporating in linear way the effects of gradients of concentrations and temperature. The mathematical problems is solved numerically through the Finite Volumes Method, in curvilinear coordinated and co-located variables, representing the diffusion through central difference and using a potential schemes for the convection terms. Original results of  flow models are shown: Isotherms, isoconcentrations and numbers of Nusselt and Sherwood in characteristic regions for the mixed internal flow problem with heat and mass are shown.

Keywords: Diffusion, convection, square cavity, laminar flow, simulation.

AGRADECIMIENTOS 

Se agradece a Conicyt y a la Universidad del Bío-Bío, por el financiamiento de los FONDECYT N° 1030209 y FPI Nº 0152112, respectivamente.

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