Experimental and numerical investigation of natural convection in a double skin facade

In this study, airflow and heat transfer in a rectangular cavity that simulates a double skin facade and includes natural convection were examined numerically and experimentally. This cavity separates the exterior space and the thermally controlled interior space. The temperatures of the surfaces that interact with these spaces were determined experimentally, while the other surfaces were regarded as adiabatic. With these temperature values, the parameters of the numerical study were defined. After the validation of the numerical model was completed based on experimental studies in the literature, the results related to flow and heat transfer in the cavity were analyzed. The numerical model provided results that agree with the air temperature values found experimentally in the cavity. Accordingly, in natural convection, with Rayleigh numbers ranging from 8.59 * 10(9) to 1.41 * 10(10) and the effect of buoyancy on the regions close to the surface, the increasing tendency of the average Nusselt number from 142.6 to 168.8 was shown. In addition, a correlation between the Rayleigh and Nusselt numbers for a cavity aspect ratio of 8.64 was constructed to evaluate the heat flux; this correlation was also shown graphically. (C) 2016 Elsevier Ltd. All rights reserved.