| Wed December 17th 2014 16:00 – 17:00 ZH286 | Seminar | A review of non-Oberbeck-Boussinesq Rayleigh-Bénard convection Janis Beckert |
Details:The Rayleigh-Bénard system is a fluid-filled container heated from below and cooled from above. It is a paradigmatic model for studying turbulent convection. This problem is usually analyzed within the framework of the Oberbeck-Boussinesq (OB) approximation to the Navier-Stokes equations, in which the temperature difference between the plates is assumed small, and thus all fluid properties except for the buoyant density can be considered constant.The magnitude of the Rayleigh number, which follows from the equations, dictates the degree of turbulence in the model. For a given fluid at a given pressure, the height of the container and the temperature difference between its plates are the only parameters that can alter the Rayleigh number of the experiment. However, overly increasing the temperature difference leads to deviations from the OB approximation. The broken symmetry of the temperature profile in vertical direction is one of the observed results in this non-Oberbeck-Boussinesq (NOB) regime. We review recent experimental, theoretical, and numerical studies of NOB effects, and possible future research on the topic. | ||
