Performance-Based Co-Simulation Framework for Evaluating Ventilation Strategies in Tropical Climate using CONTAM and EnergyPlus

Balancing indoor air quality (IAQ) and energy efficiency is a persistent challenge in mechanically ventilated office buildings in tropical climates. This study evaluated the performance of ventilation strategies such as pressurized ventilation, and demand-controlled ventilation (DCV), by using a co-simulation framework. It integrated EnergyPlus for thermal and HVAC model with CONTAM for multizone airflow and pollutant transport. DCV was implemented in EnergyPlus via the Energy Management System (EMS), using zone-level CO₂ concentrations and occupant level control from CONTAM to dynamically control outdoor air intake. The goal was to maintain indoor CO₂ below 1000 ppm, PM_2.5 lower than 25µg/m³, while minimizing energy usage. The study evaluated key metrics such as CO₂ buildup, PM_2.5 infiltration, HVAC energy consumption, and thermal comfort under building materials, ventilation scenarios and violation percentage during occupancy period of a whole year. The simulation results indicate that two strategies provided the best balances of benefits: using 20% OA and employing occupant-level with an EMS control at CO₂ threshold of 800 ppm. These approaches were effective at limiting CO₂ buildup, reducing PM_2.5 violation, and achieving notable energy savings. However, they sometimes resulted in thermal comfort deviations. Future work should explore energy recovery ventilation (ERV) and higher-efficiency filtration to further mitigate PM_2.5 while optimizing energy performance.