Calibration process and uncertainty estimation for 3D pitot tubes to enhance greenhouse gas emission measurements in smokestacks

Abstract

Carbon dioxide emissions made up from fossil fuel is a weighted contribution to the total carbon dioxide emissions in Korea. To keep on track of the long-term mitigation pathway, the new solution for enhancing the emission flow measurements more accurately in industrial smokestacks is urgent. Thus, along with the popular instrument, an S-type Pitot tube, three-dimensional Pitot tubes have been introduced to determine the emission flow in smokestacks by international standards and Korean regulations. To comply with the regulations mandated in Korea, the Korea Research Institute of Standards and Science established the three-dimensional Pitot tube calibration system for stack flow measurements assembled to the airspeed standard system. This calibration system can produce accurate pitch and velocity calibration curves for three-dimensional Pitot tubes in the range of testing pitch angle within ±30°, and have an expanded uncertainty attributed to the calibration curves (0.005 ~ 0.086) and (1.3~ 2.9)% for the prism Pitot tube and (0.008 ~ 0.175) and (1.6~3.1)% for the spherical Pitot tube.

A Self‐Powered Flow Velocity Sensing System Based on Hybrid Piezo‐Triboelectric Nanogenerator

“…It can be used to detect the flow velocity of a gas environment such as gas emissions of a smokestack and airspeed of aviation. [ 5–7 ] However, the concern regarding a pitot tube is the accuracy and capability to operate with at flow velocity. [ 8 ] The working principle of a mechanical anemometer is based on the exchange of momentum between the flow and rotating measuring element, which is widely used in meteorological and ventilation measurements.…”