Investigation on the Steady‑state of Gas–liquid Two-phase Swirling Flow Differential Pressure Based on Visualization Experiments

Unreliable radial differential pressure (RDP) measurements in gas–liquid two-phase flow are caused by variable flow patterns. To address this challenge, an approach based on active swirl regulation is reported to stabilize flow patterns and improve RDP measurement accuracy. Using an indoor visualization experimental system, the variations and underlying mechanisms of axial differential pressure (ADP) and RDP with gas and liquid flow under the action of a vane-type swirler were investigated. An RDP prediction model was established using the superficial gas and liquid velocities, and mixture density as independent variables. Compared with the original model, the new model reduced the mean absolute error by ۱۰.۸۸% (from ۲۴.۲۶% to ۱۳.۳۸%). Increasing liquid flow significantly raises the ADP by enhancing the centrifugal effect, thickening the liquid film, and enlarging the interfacial area. An increasing gas flow further amplified energy dissipation by intensifying interfacial shear and turbulent dissipation. The RDP exhibited a nonmonotonic variation, decreasing and then increasing with the increasing liquid flow, with a critical threshold at ۰.۳ m۳ h−۱, revealing the condition for establishing an effective swirling flow field. The dominant roles of swirl intensity and centrifugal force in differential pressure formation were elucidated. These findings provide an active regulation strategy and theoretical basis for stable differential pressure signal measurement in gas–liquid two-phase flow.

کلیدواژه ها:

Gas&ndash ، liquid two&ndash ، Phase flow ، Radial differential pressure ، Swirl regulation ، Flow pattern stabilization ، Swirl intensity