矩形喷嘴PM_(2.5)惯性冲击采样器的研制

Design of PM_(2.5) Inertial Impactor with Rectangular Inlet

惯性冲击器是最重要的颗粒物采样器之一,被广泛用于大气颗粒物的分级采样。设计了一种中流量的矩形喷嘴PM2.5惯性冲击采样器。根据Marple准则设计了冲击器的结构参数,用CFX软件进行了惯性冲击器内部气固两相流场的CFD模拟,得出了惯性冲击器的最优结构参数。根据得出的最优设计参数,进行了PM2.5惯性冲击器样机的结构设计,并在实验室用APS气溶胶空气动力学粒度仪进行了标定。实验标定和CFD数值模拟的结果基本吻合,当采样流量为100L/min,冲击器的切割粒径dp50=2.55μm,切割锐度σg=1.4,满足设计要求。

Inertial impactor is one of the most important particulate samplers, which is widely used for the atmospheric particulate classification. A medium flow PM2.5 inertial impactor with rectangular inlet was designed in this paper. Based on the Marple Criteria, the impactor＇ s configuration parameters were calculated here, And using commercial CFD software CFX, numerical simulation and parameter optimization for multi-parameters of the impactor were carried out in this paper, and a set of sampler prototype has been designed through model experiment in the laboratory. Furthermore, a prototype sampler has been designed according to the optimum parameters, and calculated by APS in laboratory. By numerical simulation and model experiment, the following conclusions were derived here： （ 1 ） the results of CFD simulation and calibrating experiment were consistent; （2） with 100L/min sampling flow, the impactor＇ s dp50 was equal to 2.55μm and σg was equal to 1.4.