Simulating Natural Ventilation in Early Stage Design: Combining an Occupant Behavior Model with an Airflow Network Approach

Air-conditioning is a major factor in energy consumption worldwide. Populous developing countries located in the tropics are projected to soon experience a staggering increase in the use of such systems, suggesting a future need for architects to design buildings that exploit natural means of temperature regulation. In this paper, we present a novel workflow to enable the simulation of natural ventilation in early stage architectural design. We draw on two recent advances in research: a stochastic model of occupants’ window opening behavior, coupled with the Airflow Network module in EnergyPlus to simulate inter-zone airflow. As a case study, we model several spatial configurations, identify metrics to analyze these and observe how design changes impact the building performance. Though the Airflow Network is a simplified model, it saves valuable computation time in comparison to CFD modelling, while the use of data-driven occupant behavior models can be expected to increase the accuracy of model results. We suggest that this multi-model approach allows a tangible engagement with the effects of natural ventilation in the design process, and suggest methods to foster insights during the design process.