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An Automated System for Flow Characterization at Exhaust Ducts and Smokestacks



Rodney Bryant, Artur A. Chernovsky, Joseph A. Falco, Iosif Isaakovich Shinder


This report summarizes the design and description for an automated system of velocity traverse probes. Performance of key components of the system are also described. The system is designed for conducting detailed characterizations of flow distributions in exhaust ducts and smokestacks. Accurate flow measurements in large exhaust systems for flue gases are critical for quantifying greenhouse gas and pollutant emissions due to fossil fuel combustion. Field deployment of the system has been demonstrated. It will be utilized to conduct in-line calibrations of the flow monitoring devices installed at the exhaust ducts of the National Fire Research Laboratory. The system is a prototype for future designs which can be applied to characterize flow conditions for similarly-sized exhaust ducts and smokestacks. Other potential uses of the system are for precise positioning of probes and instruments in and around adverse environments such as enclosure fires or open burns.
Technical Note (NIST TN) - 2247
Report Number


Flow Characterization, Flow Traverse, Greenhouse Gas, Emissions, Flow Calibration, Automation


Bryant, R. , Chernovsky, A. , Falco, J. and Shinder, I. (2023), An Automated System for Flow Characterization at Exhaust Ducts and Smokestacks, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed June 18, 2024)


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Created February 10, 2023