Investigation of uncertainty components of ultrasonic system for gas flow velocity measurement

Abstract

The uncertainty components of ultrasonic system for gas flow velocity measurement are described. Basic algorithm for determination of gas flow velocity is presented. The partial derivatives (sensitivity coefficients) of the gas flow velocity are determined. The influence of measurements parameters to the gas flow velocity measurement uncertainty is analyzed. It is shown that the flow profile and the angle between the sounding path and the centerline of the pipe determinate have the majority influence for gas flow velocity measurements uncertainty. In the low velocity region the influence of the times for ultrasonic signals to travel from transmitter to receiver downstream and upstream the gas flow is increasing. The influence of other parameters is slight.