化工学报 ›› 2011, Vol. 62 ›› Issue (6): 1515-1523.

• 流体力学与传递现象 • 上一篇    下一篇

涓流床中液体分布形态与滞后特性

孔祥明,程振民   

  1. 华东理工大学化学工程联合国家重点实验室
  • 出版日期:2011-06-05 发布日期:2011-06-05

  • Online:2011-06-05 Published:2011-06-05

摘要:

采用电容层析成像仪(ECT)和压力传感器在气液预液泛模式润湿床层的条件下分别测定了空气水体系在内径140 mm有机玻璃塔中由不同粒径玻璃珠所组成床层的持液量滞后和压降滞后曲线。利用平行流区模型对实验数据进行了分析,得出了不同操作状态下的膜流分率、簇状流区和气相流区的比例以及各流区的流速。发现在高的气液流速下,单相区比例较气液两相区的比例要小得多。当气体流量增加时,气相流区比例不增反减,而气液流区比例增加,这说明气液之间作用强烈,气液接触充分。在气液流区,气体流速大于液体流速,且气体流速和表观流速总是接近。

关键词: 涓流床, 电容层析成像, 持液量, 相对渗透率, 滞后, 液体分布

Abstract:

The experimental work was conducted in a plexiglass column of 140 mm ID packed with glass beads of different diameters(1.9, 3.6, 5.2 and 9.3 mm)by using air and water as the working system after the column was preflooded with high gas and high liquid flow rates to ensure complete wetting of the bed.The data acquisition of liquid holdup and pressure drop hysteresis loops was made possible by installation of pressure transducers and electrical capacitance tomography(ECT).The proportions of film flow, cluster zone and gas zone were obtained by analyzing the experiment data in different operation conditions using the parallel zone model.It was found that the proportion of single gas or cluster zone was much smaller than that of the gasliquid zone when gas and liquid flow rates were high.The proportion of gas zone decreased instead of increasing when gas flow rate increased.But the proportion of gasliquid zone increased.It indicated that there was strong interaction between liquid and gas.In gasliquid zone, gas flow rate was greater than liquid flow rate.Meanwhile, gas flow rate was always close to superficial gas velocity.

Key words: 涓流床, 电容层析成像, 持液量, 相对渗透率, 滞后, 液体分布