Reduced-scale experiments of heat transfer from integrated radiant ceiling panel and diffuse ceiling ventilation

Abstract

• Reduced-scale experiments of perforated radiant ceiling with diffuse ventilation. • Cooling power increases with increased ventilation rates. • Mapping of heat transfer coefficients for different loads and ventilation rates. • Diffuse ventilation air is pre-heated or -cooled in the plenum by radiant ceiling. Thermal ceiling systems for heating and cooling has several solutions and methods. In this study, an integrated solution that combines a radiant ceiling panel with diffuse ventilation was investigated in a reduced-scale experiment. The purpose of the experiment was to map the heat transfer from the perforated radiant ceiling panel at different ventilation rates. The experiment was scaled for similitude in the plenum. The heat transfer coefficients were compared to the literature and a previous numerical study using Computational Fluid Dynamics. The heat transfer coefficients in the plenum were on par with both the compared literature and the CFD study. It was found that the internal heat gain in the room created a high radiative-to-convective ratio, and the results were most valid for the small values (14 W/m 2 ), where the heat transfer coefficient for cooling scenarios had an increase of 20% from no ventilation to high ventilation rate. The heating scenarios did not show a conclusive change. Although the experiments showed potential, the integrated solution should be investigated further in a full-scale experiment, as some of the uncertainties and differences could be caused by the reduced scale test setup.