Measurement of drop size and distribution in an annular two-phase, two-component flow occurring in a venturi scrubber

Drop size and distribution in an annular two-phase flow occurring in a venturi scrubber were measured using a phase Doppler particle analyzer (PDPA) as a function of operating conditions such as gas velocity and liquid-to-gas ratio. At low throat-gas velocities, the maximum measured drop diameter and Sauter mean diameter increased when the liquid-to-gas ratio increased. However, at a fixed liquid-to-gas ratio, the maximum measured drop diameter and Sauter mean diameter decreased with the increase in throat-gas velocity. The experimental data tested with two theoretical distributions, namely, the upper-limit distribution function and the root-normal distribution function in terms of the shape of the drop-size distribution and the frequency values, produced a better agreement with the former than with the latter. It was observed that, in a highly dispersed drop-size distribution produced at a low throat-gas velocity of 45 m/s, a single average drop size is inadequate to describe the entire drop-size distribution, whereas at a high throat-gas velocity, 60 m/s, a single average drop size was found sufficient to describe the entire drop-size distribution formed.