Experimental assessment of radiant panel for thermal conditioning of open spaces

Abstract

Climate change resulting from the high emission of greenhouse gases has caused a continuous increase in the Earth's temperature, leading to an increase in the demand for refrigeration in the residential sector. Added to this is the heat island effect that generates even worse microclimatic conditions. Based on this idea, the CartujaQanat project was born, which seeks to recover life on the street by providing up-to-date solutions to combine the knowledge obtained from experience, tradition, innovation, and research. These solutions include reducing solar radiation, lowering the temperature of surrounding surfaces, and lowering the air temperature. Furthermore, this study explores a new concept of radiant solution adapted to outdoor spaces to improve thermal comfort and determine the radiant effect it provides since only radiant heat flux is relevant in open spaces with a low level of confinement of air. For this, the proposed solution is evaluated in a test cell to obtain its thermal behaviour under different operating conditions. Thanks to the experimentation carried out, it has been possible to obtain an inverse model to analyze the thermal behaviour of the solution. The inverse model obtained achieves high precision in its estimates and the possibility of fractioning the radiant and convective heat flux rate, allowing to evaluate the system's different operating conditions and know the solution's impact in open spaces. Thanks to this control of surface temperatures, an increase in thermal comfort by 40% is guaranteed. In addition, it prolongs the time of use of the open space, allowing attendees to be in comfort conditions for a longer period.