Validation of Velocity Field Measured with Particle Image Velocimetry of a Partially Heated Cavity

Abstract

Natural convection can be extremely relevant in the cooling process of electronic devices and the temperature and airflow motion distribution in rooms. A novel set-up has been built in this work to evaluate the velocity field in steady-state condition with only one partially heated wall. The scope of the work was to analyze the heat transfer mechanism and velocity fields in a scaled model of a room or an electronic device. Experimental analyses were conducted with the two-dimensional particle image velocimetry technique, and velocity fields have been measured for different cases. Numerical simulations have been developed for comparison purposes and validation of measurements with vector velocities maps. Following the validation, several numerical simulations have been carried out to provide a forecast of velocities values and vortex shape computed with the computational fluid dynamics model; average Nusselt number and Rayleigh number have also been calculated. A correlation for the Rayleigh and Nusselt number has been reported for the new configuration proposed. The results of calculated average velocities are in good agreement with the experimental measurements (average deviation between ±2% and ±8%), while some differences have been highlighted for the maximum velocity at the higher temperature.