Vertical slug flow in laminar regime in the liquid and turbulent regime in the bubble wake—Comparison with fully turbulent and fully laminar regimes |
| |
Authors: | TS Mayor |
| |
Affiliation: | Centro de Estudos de Fenómenos de Transporte, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias 4200-465 Porto, Portugal |
| |
Abstract: | An experimental and simulation study on free bubbling vertical slug flow in laminar regime in the main liquid and turbulent regime in the near-wake bubble region is reported. A non-intrusive image analysis technique and a previously developed slug flow simulator (SFS) were used. Two aqueous glycerol solutions (0.012-0.013 and 0.022 Pa s) were studied. A single bubble-to-bubble interaction curve was obtained. Strong interaction was found for bubbles flowing less than 3-4D apart, with slight interaction persisting for longer distances. The shape of the interaction curve bridges those for fully turbulent and fully laminar regimes. The experimental average bubble velocity in undisturbed conditions was shown not to follow the correlation-based predictions for laminar regime in the liquid. Alternative fitting coefficients are proposed. An entrance length of 50-80D (or 90-170D) was obtained for normal inlet slug length distributions centred on 2-5D (or 2-6D), for superficial gas and liquid velocities up to 0.40 and 0.30 m/s, respectively. More contrasting inlet slug length distributions were found not to converge within the length of the column (6.5 m). An overall comparison between the three regimes is presented. |
| |
Keywords: | Two-phase flow Slug flow simulation Image analysis Bubble length Bubble velocity Bubble interactions Gas expansion |
本文献已被 ScienceDirect 等数据库收录! |