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Characterization of Five-Hole Probes used for Flow Measurement in Stack Emission Testing



Iosif I. Shinder, Aaron N. Johnson, Michael R. Moldover, Bernard J. Filla, Vladimir Khromchenko


We report progress towards the goal of reducing the errors in industrial smokestack flow measurements to 1 % by replacing S-probes with calibrated 3-D probes (i.e., probes that measure 3 components of velocity). NIST calibrated a commercially-manufactured spherical probe and a prism probe at air speeds (5 m/s to 30 m/s) and pitch angles (20 to 20 °) using a yaw-nulling method similar to EPA’s Method 2F. The expanded uncertainty for 3-D air speed measurements of both probes was near 1 % at a 95 % confidence level. Most of this uncertainty is attributed to the irreproducibility of the calibration measurements and the uncertainty of the NIST’s laser Doppler anemometer air-speed standard. Thus, the 1 % goal might be possible; however, to obtain this low uncertainty, several significant uncertainties consistent with EPA Method 2F must be avoided. We document these uncertainties herein.
Proceedings Title
2018 International Symposium on Fluid Flow Measurement (ISFFM)
Conference Dates
March 21-23, 2018
Conference Location
Querétaro, Mexico, -1


Method 2F, 5 hole probes, spherical probes, prism probes, stack flow testing, 3-D pitot probes, EPA RATA, Stack Emissions Flow Measurements, Yaw-nulling 3-D probe calibrations
Created May 17, 2018, Updated March 12, 2020