Three-Dimensional Mach-Zehnder Interferometric Tomography of the Rayleigh-Be´nard Problem

A three-dimensional experimental technique based on axial tomography is demonstrated in this study for the Rayleigh-Be´nard convection problem. The technique can perform under severe blockage conditions and with a small number of projections. The major requirement of the technique is an adequate initial guess of the field and the use of an iterative inversion algorithm. In this study, five views are used to study the steady-state natural convection inside a three-dimensional rectangular cavity filled with water at Ra = 5470 ± 100 and Ra = 6140 ± 100. The reconstructed results are estimated to be accurate with a standard deviation of about 0.01°C. The temperature measurements show strong three-dimensional features in the flow.