Spatial Evaluation of the Effects of Sun Radiation and Clothing Adaptation in Indoor Comfort Simulations

Changes in clothing are one of the most effective adaptation mechanisms that occupants have to improve their personal level of satisfaction in the indoor environment. This can play a crucial role when considering daily variation or uneven conditions as it happens in case of solar radiation entering the room. Nevertheless, when simulation is conducted to assess thermal comfort, clothing is often assumed constant throughout the day or the season. The goal of this work is two-fold: on one hand, it aims at assessing the potential of clothing adaptation for providing comfort in the presence of solar radiation. On the other hand, it evaluates the sensitivity to clothing adaptation of the categorization of buildings according to the standards ISO 7730 and EN 15251, in order to assess the impact of simplified clothing assumptions on the analysis of comfort. Five clothing scenarios have been compared: four of them are given by a combination of two different strategies for daily selection of clothing and two adaptation ranges for hourly changes; the fifth one is a reference one, which assumes clothing is fully adaptable from 0.5 to 1.0. For the comparison, a thermal model of a 100 m2 shoebox office located in Milan (Italy) is used. The scenarios are calculated for a grid of points distributed in the space and the results are reported using two long-term metrics: Thermal Comfort Availability (TCA) and Thermal Comfort Usability (TCU). Comfort is assessed according to Fanger model, both standard and modified to account for solar radiation directly on the occupant.