A case study on the application of underfloor air conditioning and ventilation system in a school assembly hall

Floor return (FR) type underfloor ventilation system was installed in the assembly hall of aprimary school in Hong Kong. Experimental investigations on the airflow and temperaturecharacteristics were conducted. Pollutant distributions were also measured with different freshair supply rates. Results reveal that the use of low momentum floor supply panels reduced therisk of draught discomfort and created a more significant temperature stratifications comparedto those with fan boosted type floor air terminals. Ventilation of polluted air was localized upto the occupants breathing level. The performances of the system indicated possibilities inreduction of energy consumption and improvements in indoor air quality over the traditionalceiling-based systems.