Effects of Indoor Unit Height and Airflow Distribution on Cooling Performance and Energy Consumption in Inverter and Non-Inverter Air Conditioners
Residential buildings are the largest contributors to electricity consumption, with air conditioning (AC) systems being one of the primary consumers of electricity. Energy-saving strategies involving physical modifications to buildings are often difficult to implement in existing structures because they require high costs and large-scale structural changes. Therefore, optimizing air conditioning performance by regulating indoor airflow distribution offers a more practical alternative for improving energy efficiency. This study aims to analyze the effect of airflow distribution patterns, resulting from variations in indoor-unit installation height, on cooling performance and energy consumption in inverter and non-inverter split AC systems through laboratory experiments in a controlled test chamber. Three air distribution configurations were tested: Perfect Mixing Above (PM_Above), Perfect Mixing Middle (PM_Middle), and Displacement (D_Bottom), each combined with two occupant layouts: facing the air conditioner directly and positioned along the wall edge. The observed parameters included the rate of temperature drop, the time required to reach a comfortable temperature, indoor temperature distribution, and electricity consumption. The results showed that air conditioning performance is influenced by the interaction between compressor technology and airflow distribution patterns, rather than solely by cooling capacity. The PM_Middle configuration achieves the best balance between cooling effectiveness and energy efficiency for both inverter and non-inverter air conditioners, and inverter air conditioners with this configuration proved the most suitable choice for long-term use in residential buildings.
Keywords: Airflow distribution, Air conditioning technology, Energy efficiency, Indoor unit installation.
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