Localised human thermal discomfort assessment using high temporal resolution meteorological data: A case of University of Zimbabwe

Abstract

This study investigated the thermal discomfort patterns at the University of Zimbabwe in Harare, Zimbabwe; paying attention to the outdoor and indoor seasonal and diurnal variations. Temperature and relative humidity data from an automatic weather station located in the study area was incorporated into the temperature humidity index to retrieve outdoor human thermal discomfort patterns. Based on data availability, air temperature and humidity hourly data for the period 2014 to 2018 was used. The indoor human thermal discomfort patterns were then obtained using the linear relationship between outdoor temperatures and indoor comfort. The results show that there were only an average of 31 days per year of indoor thermal discomfort days in the hot and rainy seasons. There were on average 303 days in which at least half of the subjects felt thermally comfortable outdoors yearly. Throughout the whole year there were no heat stresses, 62 days of cold stress outdoors, and 334 days of cold stress indoors. The hot season was found to be the most thermally comfortable with 25% and 33% of thermally comfortable hours per day indoors and outdoors, respectively. It was concluded that subjects were mostly comfortable in the afternoon both indoors and outdoors. The study recommended that as more data is collected, future researchers should consider a longer period for analysis. The findings of this study are important for understanding, modelling and monitoring human thermal comfort/discomfort at learning institutions, work places and other environments. Such information can be used for making building guidelines on including systems like air conditioning units in response to climate change and increased variability.