부산대학교 도서관

Gas sampler was a kind of sampling equipment and evaluation equipment for monitoring air, and the components used for sampler flow calibration were the core components that affected the sampling accuracy. At present, the component orifice flowmeter commonly used in the flow calibration of sampler shows the characteristics of poor linearity and poor long-term stability, and its uncertainty of flow measurement was large in the flow range (1∼120) L/min commonly used in particulate sampler. In order to explore more components that could be used for the flow calibration of the inhalable particulate matter sampler, this paper have analyzedthe advantages and disadvantages of different flowmeters and the applicable flow calibration of the sampler, and determined the orifice plates and nozzle components that could ensure the processing accuracy and lower processing cost as the design objects. Using computational fluid dynamics CFD to simulate the orifice plates and nozzle components with different flow ranges, and select orifice plates and nozzle components with better linearity within the flow range of (1∼120) L/min as processing objects. According to the national standard requirements of the differential pressure flowmeter and the structural parameters provided by the simulation, the orifice plate and nozzle components meeting the requirements were machined, and the flow components processed were verified by experiment. Finally, three orifice flowmeters with flow ranges of (0.5∼5) L/min and (5∼10) L/min (10∼120) L/min are designed, which can be used for the flow calibration of particulate sampler. In the flow range, orifice flowmeters show good mechanical processing consistency and outflow coefficient linearity is better than 1.0%. The long-term stability of traffic is better than 1.5%. This study can provide theoretical support for the component design of late gas sampler flow calibration, it can also provide more choices for the selection of components for sampler flow calibrationt.