FLOW VISUALIZATION OF NATURAL CONVECTION IN A VERTICAL CHANNEL WITH ANTISYMMETRIC HEATING

摘要

Flow- and temperature-field photographs were obtained for natural convection in a vertical channel with antisymmetric heating. The heating is antisymmetric when the hot wall is heated above the ambient temperature by the same amount that the cold wall is cooled below the ambient, producing equal but opposite buoyancy forces. These opposite buoyancy forces can cause instability inside the channel. So the flow- and temperature fields are of interest for validation of numerical modeling. The flow field was obtained by means of smoke flow visualization using a laser sheet and a Drdger tube, which supplied the aerosol. A Mach-Zehnder interferometer was used to obtain the temperature field. Results were obtained over a range of aspect ratios and Rayleigh numbers ranging from a steady laminar to an unsteady turbulent flow.