Mass flow measurement of gas?liquid bubble flow with the combined use of a Venturi tube and a vortex flowmeter

TLDR: In this article, a measurement correlation was established based on the differential pressure generated across the Venturi tube and the frequency extracted from the vortex flowmeter signal, which provided a simple and practical solution to the mass flow measurement of homogeneous gas-liquid bubble flows.

Abstract: Development of effective techniques for gas–liquid two-phase flow measurement is of interest to both academic research and industrial applications. This paper presents a novel approach to the measurement of the mass flow rate of homogeneous gas–liquid bubble flow with the combined use of a Venturi tube and a vortex flowmeter. The Venturi tube and the vortex flowmeter were mounted in the same pipeline with a spacing interval of ten times the pipe's inner diameter. A measurement correlation was established based on the differential pressure generated across the Venturi tube and the frequency extracted from the vortex flowmeter signal. Experiments were conducted on a vertical upward gas–liquid two-phase flow rig under the bubble flow pattern, with the air mass flow rate from 0.2 × 10−3 to 3.2 × 10−3 kg s−1, the water mass flow rate from 3.3 to 5.2 kg s−1 and the volumetric void fraction from 0.004 to 0.246. The results show that the relative errors of the correlation for the mixture mass flow rate measurement were within ±5%, and the maximum standard deviation of the relative errors was 2.0%. This method provides a simple and practical solution to the mass flow measurement of homogeneous gas–liquid bubble flows.