A model for double-diffusive convection in an anisotropic porous layer with a constant throughflow is explored, with penetrative convection being simulated via an internal heat source. Both linear instability and nonlinear stability analyses are performed to assess the suitability of linear theory to predict the destabillisation of the throughflow. It is shown that due to oscillatory instability modes, there are three disinct regions, where increasing the ascending throughflow from rest actually has a stabilising effect, before following the standard destabilisation and stabilisation pattern. This is a previously unobserved phenomenon. The agreement between the linear and nonlinear thresholds is substantial when a small descending throughflow is introduced, although this does deteriorate for ascending throuflow.
Double-diffusive penetrative convection simulated via internal heating in an anisotropic porous layer with throughflow / Capone, Florinda; Gentile, Maurizio; A. A., Hill. - In: INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER. - ISSN 0017-9310. - 54:7-8(2011), pp. 1622-1626. [10.1016/j.ijheatmasstransfer.2010.11.020]
Double-diffusive penetrative convection simulated via internal heating in an anisotropic porous layer with throughflow
CAPONE, FLORINDA;GENTILE, MAURIZIO;
2011
Abstract
A model for double-diffusive convection in an anisotropic porous layer with a constant throughflow is explored, with penetrative convection being simulated via an internal heat source. Both linear instability and nonlinear stability analyses are performed to assess the suitability of linear theory to predict the destabillisation of the throughflow. It is shown that due to oscillatory instability modes, there are three disinct regions, where increasing the ascending throughflow from rest actually has a stabilising effect, before following the standard destabilisation and stabilisation pattern. This is a previously unobserved phenomenon. The agreement between the linear and nonlinear thresholds is substantial when a small descending throughflow is introduced, although this does deteriorate for ascending throuflow.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.