Mechanical Engineering Journal | |
Experimental results of the effect of gas composition on void fraction and bubble behavior for gas-liquid two-phase flow under stagnant water condition | |
Miki SAITO1  Satoshi NISHIMURA1  Taizo KANAI1  Yoshihisa NISHI1  | |
[1] Central Research Institute of Electric Power Industry; | |
关键词: pool scrubbing; gas-liquid two-phase flow; void fraction; wire-mesh sensor; bubble; | |
DOI : 10.1299/mej.20-00546 | |
来源: DOAJ |
【 摘 要 】
Fission product removal by pool scrubbing is known to be largely affected by the gas-liquid two-phase flow regime. The pool scrubbing performance of various carrier gases was evaluated in two-phase flow experiments by injecting helium, nitrogen, or argon through a pool of stagnant water in a column with an inner diameter of 0.5 m and a height of 8 m. The gases were supplied through a cylindrical nozzle with an inner diameter 69 mm at superficial gas velocities ranging from 0.013 to 0.053 m s-1. Measurements were conducted using a camera and two sets of a 128 × 128 wire-mesh sensors, separated by 40 mm. The visually observed gas hold-up and wire-mesh sensor-measured average void fraction decreased with increasing fraction of lighter gas in the supplied gas. Detailed analysis of the flow regime using the obtained wire-mesh sensor signals revealed that lighter gases led to a greater fraction of relatively large bubbles in the flow compared to heavier gases, causing the gas phase with the lighter gases to have a higher average rise velocity in the flow. This leads to a hypothesis that, compared to heavier gases, lighter gases break up less or coalesce more in the flow, resulting in distinct two-phase flow characteristics depending on the inlet gas composition.
【 授权许可】
Unknown