The Onset of Convection in a Layered Porous Medium with Vertical Throughflow
Tóm tắt
An analytical investigation of the effect of vertical throughflow on the onset of convection in a composite porous medium consisting of two horizontal layers has been made. The cases of iso-flux and iso-temperature boundaries are both investigated. The critical Rayleigh number depends on a Péclet number
$$Q$$
, a permeability ratio
$$K_{r}$$
, a thermal conductivity ratio
$$k_{r}$$
, and a depth ratio
$$\delta $$
. For the case of small
$$Q$$
an approximate solution is obtained, which shows that in general throughflow has a stabilizing effect whose magnitude may be increased or decreased by the heterogeneity. This solution is supplemented by an asymptotic solution valid for large
$$Q.$$
Tài liệu tham khảo
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