Sunspot analysis under varying conditions climate: Distributed radiation on cooling floor and its effect on dynamic thermal behaviour

The dynamic thermal simulation of buildings is a real challenge, in terms of regulations and labelling but also of decisions (implementation, materials choice, architectural design, rehabilitation …). Today, we lack reference models of the dynamic thermal behaviour of the cooling floor under solar radiation effect. In fact, the simulation models developed in literature are represented in a very simplified method and cannot be used for a detailed analysis of thermal comfort. The present study aims to reduce the knowledge gap and resolve the limitations such as (i) studying the effect of sunspot for a real weather conditions, (ii) visualize the dynamic thermal behaviour of indoor air and surface cooling floor relative to the sunspot shifting and (iii) predict different sunspot shape as a function of geographic location. A 3D model is presented in this paper to evaluate the sunspot impact on cooling floor coupled to underground tank under climatic conditions in Algeria. The sunspot is calculated using a coupled TRNSYS-FLUENT dynamic simulation. Simulations are run for different periods and weather conditions. The results have shown that the developed model can provide a real simulation of thermal performance of the cooling floor taking into account the sunspot shifting. The incident solar heat flux on cooling floor reaches a maximum of 300 W/m2 for Bechar city and 120 W/m2 for Oran city. A wide surface temperature ranges of 13 °C between the umbrageous and illuminated areas. For Oran weather conditions, the indoor air temperature in the umbrageous area is around 24 °C, while that of the illuminated area is 28 °C which can cause a temperature heterogeneity in the room.