Thermal comfort and heat flow characteristics of hybrid cooling systems for studio type classrooms: An experimental study

• Published in: Energy and buildings 2024-08, Vol.316, p.114316, Article 114316
• Main Authors: Chandrashekar, Rakesh, Pai, Ananth, Vivek, T., Sekar, S.K., Arıcı, Müslüm, Balaji, K.
• Format: Article
• Language: English
• Subjects: Hybrid cooling system; Indirect-direct evaporative cooling; PMV; Thermal comfort; Thermally activated building system
• ISSN: 0378-7788
• DOI: 10.1016/j.enbuild.2024.114316

A thermally activated building system (TABS) and indirect-direct evaporative cooling (IDEC) were experimentally investigated for providing the optimal thermal comfort in warm and humid climate. Simultaneous investigations were conducted in studio-type (cross-ventilated) classrooms for three cooling scenarios by operating TABS as a standalone system, integrating TABS with IDEC to introduce natural ventilation and integrating TABS with fan for forced air circulation. During the course of working hours, intermittent measurements are taken for key factors including air temperature, surface temperature, mean radiant temperature, solar radiation, air velocity, and heat flux. Different cooling scenarios were subjected to a comparative assessment in order to assess the thermal comfort index. It was observed that a hybrid system integrated with an IDEC reported a better thermal comfort band with predictive mean vote in the range of 1.1 and 1.5 neutral band, with 30 predicted percentage of dissatisfied, and the maximum heat gain of 38 W/m2. The moisture content absorbed within the structure was 1.9 on the floor and 1.4 on the wall, within the acceptable limit per DIN1052 standards. The indoor average wet bulb temperature was higher due to the supply of dehumidified air; hence the risk of condensation was eliminated.