Citation :

Adam F. Rombaoa, Shaye Caroline G. Manlupig, Angelica T. Pangilinan, "Determination and Standardization of Air Conditioning Requirements for Lecture Rooms: A Computational Fluid Dynamics (CFD) Modeling and Analysis," International Journal of Engineering Trends and Technology (IJETT), vol. 74, no. 9, pp. 408-423, 2026. Crossref, https://doi.org/10.14445/22315381/IJETT-V74I9P128

Abstract

This study presents the air-conditioning requirements for a typical lecture room at Tarlac State University by integrating cooling load calculations with computational fluid dynamics focused on thermal comfort simulation. Cooling loads for a 9 m × 7 m × 2.8 m classroom accommodating 51 occupants are calculated based on the Carrier E20 method and Department of Energy guidelines, yielding a peak cooling load of 12.12 kW for top-floor classrooms and 10.20 kW for lower floors, corresponding to two 2.5 HP and two 2.0 HP air-conditioning units, respectively. CFD simulations are performed to assess air temperature, velocity distribution, and Predicted Mean Vote at different positions for window-type and wall-mounted split-type ACUs, considering three volume flow rates with a supply air temperature of 14 °C. Results show that increasing airflow improves air mixing and shifts PMV toward the ASHRAE-recommended comfort range of −0.5 to +0.5. Optimal thermal comfort was achieved within the range of 0.25–0.35 m³/s, with 0.25 m³/s providing near-neutral conditions and 0.35 m³/s yielding slightly cool conditions, equivalent to setting the ACU to 23°C and 21 °C, respectively. Also, the results indicate that the upper position is the optimal installation location for the window-type ACU. For a temperature setting of 24 °C, simulation results indicate slightly warm conditions, particularly at lower airflow rates. The findings of this study contribute to practical recommendations for ACU sizing, placement, and operation.

Keywords

Air Conditioning Simulation, Computational Fluid Dynamics (CFD), Cooling Load Calculation, Lecture Room Temperature, Thermal Comfort Simulation.

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