The Onset of Double-Diffusive Convection in a Vertical Cylinder Occupied by a Heterogeneous Porous Medium with Vertical Throughflow

2012 ◽  
Vol 95 (2) ◽  
pp. 327-336 ◽  
Author(s):  
A. V. Kuznetsov ◽  
D. A. Nield
Keyword(s):  
Porous Medium ◽  
Vertical Cylinder ◽  
Double Diffusive Convection ◽  
Heterogeneous Porous Medium ◽  
Diffusive Convection ◽  
Vertical Throughflow ◽  
Double Diffusive

The Onset of Double-Diffusive Convection in a Vertical Cylinder With Vertical Throughflow

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
D. A. Nield ◽  
A. V. Kuznetsov
Keyword(s):  
Vertical Cylinder ◽  
Double Diffusion ◽  
Linear Stability Theory ◽  
Double Diffusive Convection ◽  
Vertical Temperature Gradient ◽  
Vertical Temperature ◽  
Onset Of Convection ◽  
Diffusive Convection ◽  
Vertical Throughflow ◽  
Double Diffusive

The effect of vertical throughflow on the onset of convection, induced by an applied vertical temperature gradient in a vertical cylinder is studied analytically using linear stability theory. This problem is important to hydrologists to investigate under what conditions convection is taking place in a well or borehole. The effect of double diffusion is included. Both nonoscillatory and oscillatory situations are studied.

The Influence of Coupled Molecular Diffusion on Double-Diffusive Convection in a Porous Medium

1986 ◽  
Vol 108 (4) ◽  
pp. 872-876 ◽  
Author(s):  
N. Rudraiah ◽  
M. S. Malashetty
Keyword(s):  
Porous Medium ◽  
Molecular Diffusion ◽  
Normal Mode Analysis ◽  
Finite Amplitude ◽  
Mode Analysis ◽  
Double Diffusive Convection ◽  
Amplitude Analysis ◽  
Cross Diffusion ◽  
Diffusive Convection ◽  
Double Diffusive

The effect of coupled molecular diffusion on double-diffusive convection in a horizontal porous medium is studied using linear and nonlinear stability analyses. In the case of linear theory, normal mode analysis is employed incorporating two cross diffusion terms. It is found that salt fingers can form by taking cross-diffusion terms of appropriate sign and magnitude even when both concentrations are stably stratified. The conditions for the diffusive instability are compared with those for the formation of fingers. It is shown that these two types of instability will never occur together. The finite amplitude analysis is used to derive the condition for the maintenance of fingers. The stability boundaries are drawn for three different combinations of stratification and the effect of permeability is depicted.

Sign in / Sign up

Export Citation Format

Share Document