PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

The study focused on air-conditioning status when different air-conditioning loads occur in a single space to achieve cooling that is not separated by walls in an office building. In this case, whether all or only some of the air-conditioning units are operated, the problem is that the air-conditioning system blows air into zones that do not require cooling. To resolve this inefficiency, the study focused on the circulating air flow generated by the interchange of supply air and return air from the air-conditioning system. As a solution to trap air flow from an air-conditioning unit into a zone that requires cooling, a method for vertically installing panels on the ceiling is proposed. The analysis was performed by Computational Fluid Dynamics analysis while changing the length of the ceiling-hanging panel length conditions (350 mm, 700 mm, and 1100 mm); the blowing angle from the air-conditioning unit (15°, 30°, and 45°); and the blowing direction from the air-conditioning unit (4 directions and 2 directions). The ceiling-hanging panels and partitions are installed between the target zone where the air-conditioning unit is operated and the non-target zone where the air-conditioning unit is not operated. Cooling efficiencies were 84.0% when both panels and partitions were installed and 82.8% when both were not installed. However, when only the ceiling-hanging panels were installed, the cooling efficiency was 89.9%. The cooling efficiency was improved by about 5.9% by simply installing the ceiling-hanging panels.

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