Application of simultaneous time-resolved 3-D PTV and Two Colour LIF in Studying Rayleigh-Benard Convection

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 ...

Apparatus for real-time acoustic imaging of Rayleigh-Benard convection.

We have designed and built an apparatus for real-time acoustic imaging of convective flow patterns in optically opaque fluids. This apparatus takes advantage of recent advances in two-dimensional ultrasound transducer array technology; it employs a modified version of a commercially available ultrasound camera, similar to those employed in nondestructive testing of solids. Images of convection ...

Heat transport in turbulent rayleigh-Benard convection

We present measurements of the Nusselt number N as a function of the Rayleigh number R in cylindrical cells with aspect ratios 0. 5</=gamma identical withD/d</=12.8 ( D is the diameter and d is the height). We used acetone with a Prandtl number sigma = 4.0 for 10(5) less, similarR less, similar4x10(10). A fit of a power law N = N(0)R(gamma(eff)) over limited ranges of R yielded values of gamma(...

Surface deflection in Rayleigh-Benard convection

Critical effects in Rayleigh-Benard convection

2014 The properties of the convection Rayleigh-Bénard phenomenon near its critical threshold of instability are shown to be closely related to those of a second order phase transition. A theory is developed in the framework of the Landau-Hopf hypothesis, and all its predictions are verified by experimental results. Tome 39 N° 7 JUILLET Classification Physics Abstracts 47 . 25Q