A linear stability analysis is performed for a plume flow inside a cylinder of aspect ratio 1. The configu- ration is identical to that used by Lopez and Marques （2013） for their direct numerical simulation study, I...A linear stability analysis is performed for a plume flow inside a cylinder of aspect ratio 1. The configu- ration is identical to that used by Lopez and Marques （2013） for their direct numerical simulation study, It is found that the first bifurcation, which leads to a periodic axisymmetric flow state, is accurately pre- dicted by linear analysis： both the critical Rayleigh number and the global frequency are consistent with the reported DNS results. It is further shown that pressure feedback drives the global mode, rather than absolute instability.展开更多
基金provided by the Agence Nationale de la Recherche under the "Cool Jazz" project
文摘A linear stability analysis is performed for a plume flow inside a cylinder of aspect ratio 1. The configu- ration is identical to that used by Lopez and Marques （2013） for their direct numerical simulation study, It is found that the first bifurcation, which leads to a periodic axisymmetric flow state, is accurately pre- dicted by linear analysis： both the critical Rayleigh number and the global frequency are consistent with the reported DNS results. It is further shown that pressure feedback drives the global mode, rather than absolute instability.
