Active control of Rayleigh-Benard thermoconvective instability with ohmic heating.

Unsteady Heating of Rayleigh-Benard Convection

The linear thermal instability of a horizontal fluid layer with time-periodic temperature distribution is studied with the help of the Floquet theory. The time-dependent part of the temperature has been expressed in Fourier series. Disturbances are assumed to be infinitesimal. Only even solutions are considered. Numerical results for the critical Rayleigh number are obtained at various Prandtl ...

Thermal Radiation in Rayleigh-Benard Instability

Thermal radiation from finite-conductivity boundaries can strongly affect the stability of horizontally unbounded, plane fluid layers heated from below. The role of thermal radiation in plane layer instabilities is studied under the assumption that the fluid medium is transparent, as a model of infrared transfer through gas layers. The solution procedure modifies a previous formulation of the c...

Pretransitional Effects in the Rayleigh-benard Instability

Investigation on Instability of Rayleigh-Benard Convection Using Lattice Boltzmann Method with a Modified Boundary Condition

In this study, the effects of Prandtl number on the primary and secondary instability of the Rayleigh-Benard convection problem has been investigated using the lattice Boltzmann method. Two different cases as Pr=5.8 and 0.7 representing the fluid in liquid and gas conditions are examined. A body forces scheme of the lattice Boltzmann method was presented. Two types of boundary conditions in the...

Thermal Modulation of Rayleigh-Benard Convection

Thermal convection in a fluid layer confined between two horizontal rigid boundaries has been studied with the help of the Floquet theory. The temperature distribution consists of a steady part and an oscillatory time-dependent part. Disturbances are assumed to be infinitesimal. Numerical results for the critical Rayleigh numbers and wave numbers are obtained. It is found that the disturbances ...