| Popis: |
A gas-liquid two-phase flow through vertical sudden contraction pipe is an area that still little is known, although its application can be seen in many industrial and hydraulic components. In this study, the mean and fluctuating flow characteristics of a vertical upward gas-liquid two-phase flow through sudden contraction pipe is studied experimentally and visually, while a new simple method of controlling the flow in order to reduce the flow fluctuation is shown. The bubbly flow upstream the contraction changes to an intermittent and fluctuating flow downstream the contraction, depending on a formation of thick and thin bubble swarms. When mounting a ring-shaped obstacle before the contraction, the vortex generation at the contraction area is reduced. That is, the flow is suggested by mounting a ring-shaped small step before the contraction to lead to flow control where the fluctuating amplitude can also be suppressed. The effects of Reynolds number, void fraction and ring position are examined. |
