本文以集中式空调房间上送上回气流为例，对室内CO2和颗粒物浓度的空间分布特征进行了模拟分析。结果表明，就呼吸带平面上的CO2和颗粒物浓度分布而言，顶送风对应的空气品质优于侧送风，送风方向仅对大粒径粒子的室内浓度分布影响较大。根据这些结果，以我国南北方两典型内陆城市为例，模拟了空调系统使用粗效过滤器时室内粒子浓度的变化，指出以大颗粒污染为主的北方城市更适合采用顶送风气流，而以小粒子污染为主的南方城市，送风方向对室内浓度无明显影响。

The concentration distributions of CO2 and particles are simulated by employing an numerical code in an central air-conditioning room with top-top air supply systems. Considering both of CO2 and particle concentration distributions in the zone of occupants’ breathing, the results show that indoor air quality is more acceptable under ceiling air supply mode comparing with sidewall air supply, and air supply direction can only affect the distribution of coarse particles indoor. When low-efficiency air filters are used in air handing units, the variations of indoor aerosol concentrations are simulated in two typical cities, which located in northern and southern of China, respectively. The result indicates that ceiling air supply is more suitable in northern cities as coarse aerosol are the major parts of the incoming air, and the direction of air supply has no effect on indoor particle distribution in southern cities for particle concentration in the fresh air is primarily determined by fine aerosols.