Optimizing Wire Mesh Sensor Design: The Influence of Wire Diameter and Spacing on Bubble Entrapment in Multiphase Flows

Bubble entrapment in wire mesh sensors (WMS) reduces measurement accuracy in multiphase flows, posing a significant challenge for industrial applications. This study quantitatively evaluates the impact of wire diameters and spacing on bubble entrapment in WMS used for gas-liquid multiphase flow analysis. Combining experiments on low void fraction bubbly flow with computational fluid dynamics (CFD) simulations, the research investigates the dynamics of gas-liquid interfaces, focusing on how the sensor's geometric configuration affects capture efficiency. A 2D CFD simulation examined air bubbles with diameters of 3.5 mm, 5 mm, and 7 mm, and velocities from 0.054 m/s to 0.113 m/s in a circular vertical channel with 34 mm diameter. WMS design parameters analysed in this study included wire transverse pitch of 1 mm and 2 mm, and wire diameters of 0.2 mm and 0.125 mm, with a vertical pitch of 1.6 mm. Experimental tests used for validation investigated air bubbles with velocities from 0.25 m/s to 0.3 m/s in a channel of 34 mm in diameter. The findings reveal a complex interaction between WMS structural parameters and performance, identifying optimal design criteria that reduce bubble entrapment occurrences and thus improve the accuracy of flow measurements. Both CFD simulations and experiments demonstrated that bubbles are entrapped when surface tension forces between the wire, air, and water exceed the buoyancy forces of the bubbles, especially when wire spacing is small relative to bubble size.