Investigation of the cooling performance and thermal comfort for 4-way cassette air conditioner with swinging motion of vanes

A numerical simulation was carried out to investigate the cooling performance and thermal comfort of a 4-way cassette air conditioner when its vanes are positioned at constant angles of 30°, 40°, 50° and 60° and swinging with a constant angular velocity. The indoor airflow characteristics and thermal comfort were evaluated. The average room temperature variation with respect to time have a good agreement with the measured data with a maximum relative error of 2 %. The average room air temperature variation according to time shows that the case of swinging vane is increased by 5.9 %, compared to the case of fixed vane angle of 60°, due to the enhancement of heat transfer by the swinging motion of discharged airflow. Moreover, the flapping discharged airflow resulting from the swinging motion makes occupants feel thermally more comfortable, based on thermal comfort indices.