Performance evaluation of different air distraction system on thermal uniformity and energy saving: A case study of a Japanese detached house

Heat shock is generated from zonal temperature differences. The pre-heating control through an air conditioning system can provide a good thermal environment, and reduce the risk of suffering heat shock in a house and with low energy consumption. In this study, a room air-conditioner (RAC) and air recirculating fan system (ARF) connected to the temperature zone of living room and washing room are applied in a detached house. The design aims to reduce the overconsumption of system energy and fulfil the healthy demand. With low air supply velocity (0.5 m/s) of ARF, the floor supply case can produce a saving of 33.9% energy for RAC to reach the target temperature 20°C in wash room (0.8？m height) in comparison to the ceiling supply case. However, return opening located on the floor was closer to RAC compared to ceiling case, hence, place of return opening should be accounted for energy reduction rate relatively