Dual-phase-lag and Dufour effects on unsteady double-diffusive convection flow in a vertical microchannel filled with porous material

• Published in: Proceedings of the Institution of Mechanical Engineers. Part E, Journal of process mechanical engineering Journal of process mechanical engineering, 2014-11, Vol.228 (4), p.272-285
• Main Author: Ajibade, Abiodun O
• Format: Article
• Language: English
• Subjects: Boundaries; Channels; Fluid flow; Flux; Laplace transforms; Mathematical analysis; Mathematical models; Porosity; Porous materials; Temperature effects; Unsteady
• ISSN: 0954-4089; 2041-3009
• DOI: 10.1177/0954408913500949

This article investigates the combined effects of diffusion-thermo and dual-phase-lags on unsteady double-diffusive convection flow in a vertical microchannel filled with porous material. The channel boundary plates are kept at asymmetric thermal as well as concentration conditions with velocity slip and temperature, as well as concentration jumps on the boundaries. The energy as well as concentration equations follow the dual-phase-lag heat conduction model. The method of Laplace transform was used to solve the resulting governing equations while the Laplace expressions are inverted by the Riemann-sum approach. The effect of different flow parameters on mass flux as well as mean chemical concentration and mean fluid temperature within the channel are investigated. It is interesting to remark that the mass flux increases within the channel as the porosity increases while the mean temperature of fluid can be increased by simultaneously growing the Dufour number and thermal retardation time (τT ).