Evaluation of thermal comfort in naturally ventilated school classrooms using CFD

This paper investigates the performance and control of natural ventilation during the heating season in order to avoid occupant discomfort. The current study examined different window configurations under a wide range of external temperatures and wind speeds using a CFD simulation tool. The results showed that thermally comfortable indoor conditions could be achieved in a UK classroom when external temperatures are as low as 8°C using high-level openable windows. At lower external temperatures, occupants are predicted to be thermally dissatisfied due to localised discomfort caused by draughts. The results from the CFD model also suggest that acceptable internal thermal conditions can be maintained with wind speeds up to 10m/s, for an external temperature of 10°C. The PMV results indicated that thermal comfort is achieved and is uniformly distributed within the classroom. This work will enable the UK’s Education Funding Agency to have a greater understanding of the effective control of windows to eliminate wintertime discomfort and avoid unnecessary heating for naturally ventilated spaces.