EXPERIMENTAL DETAILS

The apparatus used for experiments of the present study are described in the following sections. In experimental procedure followed for growth of KDP crystals is also discussed.

CONVECTION IN A RECTANGULAR CAVITY

Experiments are reported for studying fluid convection in a rectangular cavity. The temperature difference maintained across the horizontal surfaces of the cavity leads to unstable density gradients in the fluid medium. In turn, fluid motion in the form of closed loops is initiated in the cavity. The configuration studied, called Rayleigh-Benard convection is a problem of fundamental as well as practical importance. The flow patterns associated with Rayleigh-Benard convection show a sequence of transitions, leading from steady laminar to unsteady turbulent flow. The strength of convection is quantified by the Rayleigh number, a dimensionless parameter. The Rayleigh number is a measure of the ratio of energy released in the buoyancy field to that lost by viscous dissipation. The values realized in the present experiments are quite large in comparison to the critical Rayleigh number of 1707 reported for a horizontal differentially heated infinite fluid layer at the onset of convection.

Figure 5.12: Schematic Drawing of the rectangular cavity experimental set up.