Unsteady natural convection in a liquid-saturated porous enclosure with local thermal non-equilibrium effect

Title

Unsteady natural convection in a liquid-saturated porous enclosure with local thermal non-equilibrium effect

Creator

Siddheshwar P.G.; Siddabasappa C.

Description

Stability analysis of free convection in a liquid-saturated sparsely-packed porous medium with local-thermal-non-equilibrium (LTNE) effect is presented. For the vertical boundaries freefree, adiabatic and rigidrigid, adiabatic are considered while for horizontal boundaries it is the stress-free, isothermal and rigidrigid, isothermal boundary combinations we consider. From the linear theory, it is apparent that there is advanced onset of convection in a shallow enclosure followed by that in square and tall enclosures. Asymptotic analysis of the thermal Rayleigh number for small and large values of the inter-phase heat transfer coefficient is reported. Results of DarcyBard convection (DBC) and RayleighBard convection can be obtained as limiting cases of the study. LTNE effect is prominent in the case of BrinkmanBard convection compared to that in DBC. Using a multi-scale method and by performing a non-linear stability analysis the GinzburgLandau equation is derived from the five-mode Lorenz modal. Heat transport is estimated at the lower plate of the channel. The effect of the Brinkman number, the porous parameter and the inter-phase heat transfer coefficient is to favour delayed onset of convection and thereby enhanced heat transport while the porosity-modified ratio of thermal conductivities shows the opposite effect. 2020, Springer Nature B.V.

Source

Meccanica, Vol-55, No. 9, pp. 1763-1780.

Date

2020-01-01

Publisher

Springer

Subject

Adiabatic; BrinkmanBard convection; DarcyBard convection; Freefree, isothermal; Local thermal non-equilibrium; Porous enclosures; Rigidrigid; Stability analyses

Coverage

Siddheshwar P.G., Department of Mathematics, CHRIST (Deemed to be University), Hosur Road, Bangalore, 560 029, India; Siddabasappa C., Department of Mathematics and Statistics, M. S. Ramaiah University of Applied Sciences, Bangalore, 560 058, India

Rights

Restricted Access

Relation

ISSN: 256455; CODEN: MECCB

Format

Online

Language

English

Type

Article

Identifier

https://doi.org/10.1007/s11012-020-01198-y

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