Numerical study on distribution of age of air in multiple rooms ventilated by multiple air handling units with recirculation

The age of air is a commonly used concept in evaluating indoor air quality (IAQ). This study investigated the age of air distribution and its influencing factors in multiple rooms ventilated by multiple AHUs with recirculation. A hypothetical case involving three rooms and two AHUs was thoroughly studied by using an effective numerical method. The results revealed that, for ventilation systems involving multiple rooms and AHUs, the recirculation has a potential to significantly change both the magnitude and distribution pattern of age of air indoors.