Developing the methodology to investigate the thermal comfort of hot-humid climate under different ventilation modes

Abstract

This study presents the development of an adaptive thermal comfort model for the hot and humid climate in Taiwan. We conducted field surveys in several offices and classrooms at National Taiwan University through a portable system which used Raspberry Pi, a small single-board computer, as processors to connect environmental sensors and as questionnaire user interface platform. This allowed us to collect indoor environmental data and investigate subjects' responses simultaneously. The advantage of the portable system is to expand the pools of data collection. The field surveys can be set up and conducted in different classrooms or offices efficiently. In total, this study collected 257 samples. The thermal comfort profiles of two different ventilation strategies (i.e., air-conditioning (AC) and natural ventilation (NV)) were analysed. The results indicate that the actual percentage of dissatisfaction (APD) has the same trend as the predicted percentage of dissatisfaction by Fanger (PPD). However, when the predicted mean vote (PMV) is in the range of -0.5 to 0.5, the APD is approximately 20% higher than the PPD. The study also found that PMV underestimates subjects' thermal sensation in both ventilation strategies.