Application of thermal comfort assessment models to indoor areas near glazed walls – experimental evaluation
Oliveira, António Manuel Figueiredo Freitas
In this paper, some of the results of an experimental study are presented. Its purpose was to better understand the impact of glazing on thermal comfort of users of indoor spaces (living and working), especially in the areas near glazed walls. Glazed elements, such as windows and glazed doors, allow visual access to the outdoor environment and the entrance of natural light and solar heat gains but they are often the cause of unwanted heat losses and gains and are disturbing elements in obtaining thermal comfort, both in global terms and in what concerns local discomfort due to radiant asymmetries and/or air draughts. Furthermore, solar radiation directly affecting users in the vicinity of glazing can also cause discomfort. These disturbances are recognized by users, both on cold winter days and on hot summer days. To assess thermal comfort or thermal neutrality of a person in a particular indoor space, it is important to know their location within that space. Thus, in order to adequately assess thermal comfort in the areas near the glazing, the indoor thermal environment must be characterized for this specific location. In this study, two indoor spaces (a classroom and an office-room) of a school building were monitored at different periods of the year. The measurements of the environmental parameters were performed both in the center of the rooms and in the areas near the glazing. Five models of thermal comfort assessment were then applied to the results, in order to compare the comfort conditions between the two studied locations and to evaluate the applicability of these models to the areas close to glazed walls. It was observed there was clearly a greater variability of comfort conditions in the vicinity of the glazed walls when compared to the center of the rooms. The application of thermal comfort assessment models to the two studied rooms was able to reveal the differences between the two compared locations within each space. It was also possible to show the effect of incoming solar radiation and the influence of the geometry of the spaces and of the ratio between glazed area and floor area by comparing the results for both spaces. The assessment model proposed by LNEC (Portuguese National Laboratory of Civil Engineering) proved to be the most adapted to Portuguese users’ habits.