轻型车颗粒物质量排放测量影响因素分析

Analysis of the Effect Factors of the Light-duty Vehicle Particulate Matter Mass Emission Measurement

本文通过对称重环境、滤纸预处理时间、背景颗粒物质量和空气浮力等因素进行对比试验，分析这些因素的变化对颗粒物质量测量结果的影响。结果表明：相对湿度越靠近45％，颗粒物质量测量的偏差越小，结果越稳定；在6-10小时的预处理时间段对滤纸进行称量，既能节约时间成本，又能保证测量精度；适当增加日常背景颗粒物测量频率，并绘制当Et背景颗粒物质量变化图，能及时修正背景颗粒物影响；空气浮力对颗粒物质量的影响主要是由大气压力的波动造成的，应及时对试验前后滤纸质量进行浮力修正。

Through contrast testing on the factors, such as weighing environment, the filter pretreatment time, the background particulate mass and air buoyancy, this paper analyzes the effect on particulate mass measurements when these factors are changed. The results indicate that the closer to 45% the relative humidity is, the smaller the particle mass measurement error will be with more stable results. Weighting the filter paper within the pretreatment period of 6 to 10 hours is both time-saving but also accurate. Appropriately increasing the daily background particulate measurement frequency and drawing the same day background particulate mass change chart can timely modify background particulate impact. Since the influence of air buoyancy of the particulate mass is mainly caused by fluctuations in the atmospheric pressure, the filter mass should go through buoyancy correction before and after the test.