以典型的空调房间为例，分析了新风和回风对室内空气品质的影响。研究表明室内污染源的不断增加 是室内空气品质恶化的主要原因，新风的质量直接影响室内空气品质，回风是室内空气的二次污染源。导出了新 风和回风对室内空气污染的理论计算公式，通过仿真表明：基于室内空气中典型的有害气体体积分数（以CO₂为 代表）的变化来控制新风量，是非常有效的。

The influence of outside air and return air on the IAQ in a typi cal air-conditioning room is analyzed. It is proved that the increasing indoor contamination makes the IAQ worse, the outside air quality has a direct effect on the IAQ, and the return air produces secondary pollutes. The theoretical formula about outside air, return air and the contaminant is induced. The simulation results show that controlling the outside air volume by contaminant mass fractin (CO₂) can save energy and improve the IAQ effectively.