Thermal Chaotic Mixing With Imposed Heat Flux In a Mixer With Alternately Rotating Walls

Kamal El Omari (1) , Yves Le Guer (1)

1 LATEP - Laboratoire de Génie Thermique Énergétique et Procédés (EA1932)

We investigated mixing and heat transfer enhancement in a two-rod mixer for a highly viscous fluid. The mixer was composed of two circular rods maintained vertically in a cylindrical tank. The rods and tank could rotate around their revolution axis. Chaotic flows were obtained by imposing temporal modulations of the rotational wall velocities. We studied the effects of different stirring protocols and flow configurations leading to chaotic flows on the efficiency of mixing and heat transfer for the particular wall boundary condition of constant heat flux. One of the objectives of this work was also to compare the Neumann and Dirichlet wall boundary conditions for the thermal chaotic mixing. For this purpose, we used different statistical indicators as tools to characterize the mean value of the fluid temperature and its homogenization. The results showed a significant enhancement of the heat transfer for the case of an alternated stirring protocol.

Mots clés: chaotic mixing; heat transport; wall heat flux; unstructured finite volumes

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]; Thermique [physics.class-ph]; Thermique [physics.class-ph]

Kamal El Omari, Yves Le Guer. Thermal Chaotic Mixing With Imposed Heat Flux In a Mixer With Alternately Rotating Walls. 2009. ⟨hal-00435242v1⟩