基于原位稀释技术的口罩颗粒物过滤效率测试仪校准研究  

Study on the Calibration Method for the Mask Filter Efficiency TesterBased on In-Situ Aerosol Dilutor Technique

作　　者：张明 邹亚雄 王婷 刘巍 刘伟光 徐广强 杨杰 ZHANG Ming;ZOU Yaxiong;WANG Ting;LIU Wei;LIU Weiguang;XU Guangqiang;YANG Jie(Qingdao Institute of Metrology Technology,Qingdao 266100,China)

机构地区：[1]青岛市计量技术研究院,青岛266100

出　　处：《计量科学与技术》2024年第1期37-43,62,共8页Metrology Science and Technology

基　　金：国家市场监督管理总局科技计划项目(2022MK142)。

摘　　要：提出以一种原位气溶胶稀释器作为标准器,用于口罩颗粒物过滤效率测试仪的校准方法。该方法可以弥补传统校准方法(标准光度计法和标准滤膜法)在可操作性和溯源性方面的不足。原位气溶胶稀释器以多根限流毛细管组合和气溶胶原位稀释为特点,是一种结构型式满足在口罩夹具位置接入使用的限流式气溶胶稀释器。在工况流量已知的情况下,经过标定的稀释器,可根据校准过程中采集到的上下游差压,计算得到稀释器的稀释比。为证明该流量法稀释比可以直接转化为稀释器所提供的过滤效率参考值使用,文中针对稀释比校准方法进行了讨论。将校准过程类比于对气溶胶颗粒的同轴非等速采样,进行了斯托克斯数的推导计算,说明了所使用限流毛细管的吸入效率接近1。计算得到伴有扩散损失的毛细管内的输送效率大于0.99。使用原位气溶胶稀释器针对典型测量对象开展校准实验,并进行了参考值的不确定度分析。上述内容共同验证了稀释法校准的可行性和有效性。This paper introduces a calibration method for mask particle filtration efficiency testers,employing an in-situ aerosol dilutor as a standard device.This novel approach aims to address the limitations of operability and traceability inherent in traditional calibration methods such as standard photometers and filter membrane techniques.Characterized by a combination of multiple flow-limiting capillaries and in-situ aerosol dilution,the in-situ aerosol dilutor is designed to fit and function at the mask fixture position.When operating at a known flow rate,the calibrated dilutor calculates its dilution ratio based on the differential pressure data gathered during calibration.The article further discusses the calibration method for the dilution ratio,asserting that this ratio can be directly converted to a reference value for the dilutor's filtration efficiency.The calibration process is compared to coaxial non-uniform aerosol particle sampling,with a derived calculation of the Stokes number showing that the capillary suction efficiency is near 1.Additionally,the transport efficiency in the capillaries,accounting for diffusion loss,is calculated to be over 0.99.Calibration experiments were conducted with the in-situ aerosol dilutor on typical measurement objects,accompanied by an uncertainty analysis of the reference values.Collectively,these findings substantiate the feasibility and effectiveness of the dilution method calibration.

关 键 词：计量学 颗粒物过滤效率 计量溯源 稀释器 流量法稀释比 不确定度 

分 类 号：TB99[一般工业技术—计量学]