Adaptive thermal comfort of naturally ventilated classrooms of elementary schools in the tropics

Abstract

Thermal comfort is one of the very important factors in enhancing the human quality of life, including students who spend a lot of times learning in schools. This article was intended to analyze the students’ adaptive thermal comfort in naturally ventilated classrooms of the elementary schools in the tropical city of Makassar. The study analyzed data gathered from 33 surveyed classrooms in six primary schools. The recorded data consisted of the personal and adaptive behavior of 1,111 students, and the thermal environments of the classrooms. At the same time, students filled out the questionnaires asking their thermal sensation, comfort level, and thermal preferences against the classrooms’ thermal environments. The results of measurements showed that the indoor mean air temperature, air humidity, and air velocity were 30.4 °C, 68%, and 0.1 m/s, respectively. They indicated that the classrooms had the hot temperature, high humidity, and low air velocity. The calculated PMV based on these parameters showed that about 90% of students felt either warm (+2) or hot (+3). The PMV overestimated the actual students’ thermal comfort where more than 85% of students voted slightly cool (-1), neutral (0), and slightly warm (+1). In addition, the neutral temperature predicted by PMV was 25.5 °C. This neutral temperature was very low in comparison to 30.2 °C calculated by using thermal sensation vote (TSV). These suggested that students of elementary schools in the tropic were tolerant to the hot environment. The use of the adaptive models to calculate the neutral temperature of students presented similar results gathered from actual votes. Therefore, the adaptive model became the best method to explain the thermal comfort of students in the elementary schools in the tropics.