Pressure Drop Reduction with Surfactant in Vertical Upward Two-Phase Flow

Abstract

The effect of surfactant on pressure drop and flow structure was investigated in vertical upward two-phase flow. Simultaneous measurements of spatio-temporal characteristics of liquid holdup and differential pressures were conducted in a 25.8mm i.d., 4.2m long acrylic pipe. The effectiveness of surfactant in reducing the pressure drop was observed. The pressure drop reduction (PDR) of up to 40% for slug flow and 15% for churn/annular flow was achieved. The PDR decreases with increasing the liquid volumetric flux for both flow regimes. The PDR in flow was caused by the reduction of the gravitational pressure drop. A decrease in wave frequency for annular flow was observed after the addition of surfactant, which made the fluctuation of the pressure gradient to be large.