Applying CFD simulation in analysing split-type air-conditioner performance at buildings

This paper introduces a computation approach in evaluating split-type air-conditioner performance when their outdoor condensing units are placed at a re-entrant or a light well of an apartment building. In a multi-storied building, heat rejection by these condensing units induces a buoyant airflow. The adverse temperature environment could significantly affect the condenser performance, particularly for those at the upper levels of the building. The consequence is a degradation of the overall capacity and efficiency of the air-conditioners. Building professionals are in need of a practical simulation approach to assist in the decision making process during the early stage of the design work. A sensitivity test is quoted as an example, together with the discussions on the validity of the work.