Effect of Distortion in Velocity Profile on Flow Measurements Using Averaging Flow Sensors

Abstract

This article reports the analysis on the flow interference due to the pressure-averaging probe. The disturbance in the velocity field generated by elbows with radii of curvature of 1D and 3D (D-internal diameter of a pipeline) were investigated based on the results recorded by selected probes with various cross-sections installed at distances in the range of 3D to 20D from the elbow. The uncertainty in the current measurement is 8.26% for a circular probe. The uncertainty was related to the distance between the probe and the elbow and the relative location of the elbow with respect to the probe. This uncertainty was found to significantly depend on the design of the cross-section of the probe. Unsteady RANS computations with the standard k-ω model are used in the current numerical approach. The distributions of the velocities and pressures of fluid flow in the vicinity of the probe were determined. Mathematical modeling can also provide guidance to improve and adapt the metrological properties of the flowmeter to the conditions of its place of installation.

Keywords

• flow-averaging pitot tubes
• elbow flow
• CFD
• flow-behind obstacles