Metrological Performances of Mass Flow Controllers for Dynamic Gas Diluition
نویسندگان
چکیده
The dynamic method of generating reference Volatile Organic Compounds (VOC) mixtures at trace level requires the uninterrupted blending of the component flows. The accurate control of the dilution air flows can be realized by Mass Flow Controllers (MFC). Accuracy and stability of MFC are here measured and discussed in order to verify their use in dynamic gas dilutors. Long term stability confirm the necessity of calibrating MFC before each use. MFC accuracy results not pressure drop dependent, but limited by the short term stability for flows below than 70% of MFC full scale and generation time shorter than 5 minutes.
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