Bayesian optimization of supply air direction in existing aircraft for cabin air quality improvement

Over the last twenty years, it has been confirmed that airborne infectious diseases can be transmitted within airplane cabins. To minimize the risk of infection, it’s beneficial to boost the ventilation system’s performance to better eliminate infectious particles in these cabins. Many research studies have concentrated on enhancing ventilation performance by suggesting new system designs. However, these new designs can only be implemented in future, newly-built airplanes.

At present, numerous airplanes are still in operation daily, and their ventilation systems also require improvement for more effective air contaminant removal. One potential solution involves tweaking the direction of the supplied air using simple airflow deflectors. This study introduces a method for optimizing the direction of ventilation in airplane cabins, utilizing the Re-field synergy index and Bayesian optimization. A verified numerical model was employed to determine the air distribution and transport of air contaminants in a single-row, single-aisle airplane cabin, to derive the Re-field synergy values.

The Bayesian optimization method was then used to pinpoint the direction of the supplied air that maximizes the Re-field synergy, thereby increasing the effectiveness of mass transfer. The optimized air supply direction was then assessed in a 7-row single-aisle airplane cabin to illustrate the improved ventilation performance. The findings reveal that the proposed method, based on the Re-field synergy index and Bayesian optimization, can effectively optimize the direction of the supplied air, leading to improved removal of air contaminants in airplane cabins. In a 7-row single-aisle airplane cabin, the optimized air supply direction can decrease the average concentration of air contaminants in the passengers’ breathing zone by as much as 23%.