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Convective drying of an individual iron ore pellet - analysis with CFD. (English) Zbl 1219.80068

Summary: The objective of this paper is to model convective drying of an individual iron ore pellet placed in a free stream of air with the aim to clarify the different stages of drying. A numerical model taking into account capillary flow of liquid moisture and internal vapor flow is developed and implemented in a commercial available software for Computational Fluid Dynamics where also the flow around the pellet is simulated, yielding heat- and mass transfer coefficients as a function of position. A real pellet is optically scanned for its geometry and simulations of the drying are compared to experiments with very good agreement. The result clearly shows four stages of drying; (i) evaporation of liquid moisture at the pellet surface, (ii) surface evaporation coexisting with internal drying as the surface is locally dry, (iii) internal evaporation with completely dry surface and (iv) internal evaporation at boiling temperatures. A moisture front moving towards the core of the pellet will start to develop at the second drying stage and the results show that the front will have a non-symmetrical form arising from the surrounding fluid flow.

MSC:

80A20 Heat and mass transfer, heat flow (MSC2010)
76S05 Flows in porous media; filtration; seepage
76M20 Finite difference methods applied to problems in fluid mechanics
80M20 Finite difference methods applied to problems in thermodynamics and heat transfer
76F60 \(k\)-\(\varepsilon\) modeling in turbulence
76F25 Turbulent transport, mixing

Software:

ANSYS-CFX
PDFBibTeX XMLCite
Full Text: DOI

References:

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