The study was conducted to investigate the effects of wall-mounted air conditioning systems on airflow and thermal comfort in enclosed spaces with high thermal loads. Within the scope of numerical analyses, the effect of different air blowing nozzle geometries and blowing angles on air distribution was evaluated using Computational Fluid Dynamics (CFD). Three different air blowing nozzle models were analyzed and compared in terms of airflow, temperature distribution, PMV (Predicted Mean Vote), and PD (Predicted Percentage of Dissatisfied) parameters. For the vertical blowing angle, 60° and 75° were determined to provide the most efficient cooling performance. In the horizontal blowing angle analysis, 67.5° and 75° were found to offer the most favorable conditions in terms of both temperature uniformity and thermal comfort. Additionally, the improved air blowing nozzle geometry, referred to as Model-3, was observed to enhance temperature distribution in the room and lower average temperature values. However, this design produced high PD values in terms of airflow velocity, indicating that certain adjustments are necessary to improve user comfort. The findings obtained from this study are expected to contribute to design evaluations related to airflow management in HVAC systems.
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