Calibração do índice de conforto térmico temperatura fisiológica equivalente (pet) para as áreas abertas de Pelotas - RS

Abstract

The urban environment, increasingly densified, and the variations that occur in the external space as the local microclimate, influence the satisfaction of its users to the thermal environment. Thermal comfort in open spaces interferes from public health to urban planning. For the verification of comfort levels in outdoor areas, survey methods are employed. By adopting the use of a thermal comfort index for outdoor areas in conjunction with field thermal comfort interviews (surveys), it is possible to determine ranges of thermal perception. In this study, the objective is to carry out the calibration procedure of the thermal comfort index Equivalent Physiological Temperature (PET) for the open spaces of the city of Pelotas - RS characterized by the humid subtropical climate (Cfa - Koppen-Geiger), which has hot summers and cold winters, in order to assess the thermal perception of the resident population. One thousand six hundred and seventy-nine questionnaires were validated over the 53 monitoring campaigns carried out between July 2019 and March 2020 and, simultaneously, the climatological data were recorded. The questionnaires addressed information about participants' biometrics, metabolic activity performed, thermal insulation of clothing, use of space, acclimatization, and thermal and ventilation perceptions. Field activities took place at five different points in the city defined for the analysis. Monitoring campaigns were interrupted from March 2020 due to the pandemic caused by Sars-Cov-2. For data recording, the TGD-400 equipment was used to monitor the variables of globe temperature, dry bulb temperature and wet bulb temperature, as well as air velocity. To record the globe temperature, as recommended by the literature for studies in open spaces, a 2” globe in medium gray color was used. The data collected through the questionnaires and the recording of climatic variables enabled the determination of mean radiant temperature (MRT) and physiological equivalent temperature (PET) values. From the PET values it was possible to determine the thermal perception ranges for the open spaces of the city. For the sample obtained, the thermal comfort range varies between 17° and 26°C PET, respectively, corresponding to the lower and upper limits of the range.