Dynamics of a single buoyant plume in a FENE-P fluid

The dynamics of a single laminar buoyant plume in a FENE-P (finitely extensible nonlinear elastic-Peterlin) fluid has been investigated by performing a series of direct simulations over a range of Weissenberg numbers. Examination of this flow has given insight into the heat transfer reduction phenomenon observed recently in more complex Rayleigh-Benard turbulence. The simulations, which were performed with a Rayleigh number of 2.53×106 and a maximal polymeric extension of L = 100, show that the wall heat flux is reduced by about 28% at a Weissenberg number of 20, which is in reasonable agreement with the results obtained in Rayleigh-Benard turbulence. In addition, the global flow kinetic energy was reduced by about one order of magnitude.