Lim Jun-Hyung, Yook Se-Jin
School of Mechanical Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
School of Mechanical Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
Environ Res. 2022 Mar;204(Pt C):112302. doi: 10.1016/j.envres.2021.112302. Epub 2021 Oct 30.
Aerosol samplers are generally classified into particulate matter (PM or PM) and total suspended particle (TSP) samplers. As changing the cutoff size is cumbersome, it necessitates either replacing the particle size separator or adjusting the sampling flow rate. In this study, a novel high-volume aerosol-sampling inlet with an adjustable cutoff size was developed. Its performance was evaluated at a sampling flow rate of 1000 L/min of road dust. The cyclone separator installed with the newly developed inlet absorbed airflow from all directions. The cutoff size of this inlet was easily adjustable using the guide vane angle. For the guide vane angles of 29°, 42°, and 90° (at a 2 km/h freestream velocity), the cutoff sizes were 2.59, 9.92, and 26.2 μm, respectively. At the 90° angle of the guide vanes and the free stream velocity of 2 km/h, no rotational airflow occurred inside the cyclone separator to allow TSP sampling. Increasing the freestream velocity to 16 km/h at angles of 29° and 42° decreased the cutoff size by 0.12 and 0.45 μm, respectively; finely adjusting these angles further reduced the cutoff size to 0.04 and 0.07 μm, respectively. Thus, an almost constant cutoff size was possible. The developed inlet allowed sampling of PM, PM, or TSP using a single device.
气溶胶采样器通常分为颗粒物（PM或PM）和总悬浮颗粒物（TSP）采样器。由于改变截止尺寸很麻烦，这就需要更换粒径分离器或调整采样流速。在本研究中，开发了一种新型的具有可调截止尺寸的大容量气溶胶采样入口。在道路扬尘采样流速为1000 L/min的情况下对其性能进行了评估。与新开发的入口一起安装的旋风分离器从各个方向吸收气流。该入口的截止尺寸可通过导向叶片角度轻松调节。对于导向叶片角度为29°、42°和90°（自由流速度为2 km/h时），截止尺寸分别为2.59、9.92和26.2μm。在导向叶片角度为90°且自由流速度为2 km/h时，旋风分离器内部未出现旋转气流，从而可以进行TSP采样。在29°和42°角度下将自由流速度提高到16 km/h时，截止尺寸分别减小了0.12和0.45μm；进一步微调这些角度可将截止尺寸分别进一步减小到0.04和0.07μm。因此，几乎可以实现恒定的截止尺寸。所开发的入口允许使用单个设备对PM、PM或TSP进行采样。
