Instability of a horizontal porous layer with local thermal non-equilibrium: Effects of free surface and convective boundary conditions

被引:22
作者
Barletta, A. [1 ]
Celli, M. [1 ]
Lagziri, H. [1 ]
机构
[1] Alma Mater Studiorum Univ Bologna, Dept Ind Engn, I-40136 Bologna, Italy
关键词
Porous medium; Local thermal non-equilibrium; Linear stability; Darcy-Benard problem; Biot number; DARCY-BRINKMAN CONVECTION; VISCOUS DISSIPATION; BENARD INSTABILITY; MIXED CONVECTION; ONSET;
D O I
10.1016/j.ijheatmasstransfer.2015.05.026
中图分类号
O414.1 [热力学];
学科分类号
摘要
The onset of convective instability in a horizontal porous layer saturated by a fluid is studied. A regime of local thermal non-equilibrium (LTNE) is considered. The lower plane boundary is an impermeable isothermal wall, while the upper boundary is a free surface with finite heat transfer coefficients to the external environment. The temperature boundary conditions at the free surface are parametrised by two Biot numbers: one for the solid and one for the fluid. A modal linear stability analysis of the basic motionless state is carried out. Limiting cases allowing for an analytical dispersion relation are defined and analysed. The general regime of linear instability is investigated by a numerical solution of the governing differential equations for the normal modes. The neutral stability condition, as well as the critical value of the Darcy-Rayleigh number, is studied in some asymptotic cases and in the general case. (C) 2015 Elsevier Ltd. All rights reserved.
引用
收藏
页码:75 / 89
页数:15
相关论文
共 28 条
[1]   Effects of viscous dissipation on the convective instability of viscoelastic mixed convection flows in porous media [J].
Alves, L. S. de B. ;
Barletta, A. ;
Hirata, S. ;
Ouarzazi, M. N. .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2014, 70 :586-598
[2]  
[Anonymous], J POROUS MEDIA
[3]   Onset of Darcy-Benard convection using a thermal non-equilibrium model [J].
Banu, N ;
Rees, DAS .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2002, 45 (11) :2221-2228
[4]   Local thermal non-equilibrium analysis of the thermoconvective instability in an inclined porous layer [J].
Barletta, A. ;
Rees, D. A. S. .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2015, 83 :327-336
[5]   Local thermal non-equilibrium effects in the Darcy-Benard instability with isoflux boundary conditions [J].
Barletta, A. ;
Rees, D. A. S. .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2012, 55 (1-3) :384-394
[6]   Local thermal non-equilibrium flow with viscous dissipation in a plane horizontal porous layer [J].
Barletta, A. ;
Celli, M. .
INTERNATIONAL JOURNAL OF THERMAL SCIENCES, 2011, 50 (01) :53-60
[7]  
Barletta A, 2011, ADV STRUCT MAT, V2, P381, DOI 10.1007/8611_2010_8
[8]   Local thermal non-equilibrium effects in the Darcy-Benard instability of a porous layer heated from below by a uniform flux [J].
Celli, M. ;
Barletta, A. ;
Storesletten, L. .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2013, 67 :902-912
[9]  
Drazin PG., 2004, HYDRODYNAMIC STABILI, V2
[10]   Local thermal non-equilibrium effects on the onset of convection in an internally heated layered porous medium with vertical throughflow [J].
Kuznetsov, A. V. ;
Nield, D. A. .
INTERNATIONAL JOURNAL OF THERMAL SCIENCES, 2015, 92 :97-105