摘要
绝热层流泡状流是泡状流研究中的一个基础范例 .目前描述绝热层流泡状流常采用的双流体模型由于相间作用考虑欠缺而适用性差 .本文结合理论和实验研究结果导出了描述壁面“排斥”作用的表达式 ,并建立了一个封闭的双流体模型 .模型预测值和实验值的比较表明 ,由于相间作用的合理考虑 。
The universal basic averaged equations for bubbly flow were developed by applying the time averaging operator to the local instantaneous flow equations. According to analysis of the motion of bubbles in the flow field, the constitutive relations for interfacial momentum exchanges caused by interface-averaged stress, and interfacial momentum exchanges caused by asymmetric stress distributions on interfaces which include drag, virtual mass force, lift and wall-force were determined. A new formulation was proposed for wall-force, which was derived from theoretic research and corrected by experimental data. Influence of bubble deformation on the flow was also considered as a correcting coefficient Cw in the formulation of wall-force. The analysis of the stress in the phases indicated that the stress in gas phase is negligible in comparison with interactions between the phases. The shear stress in liquid phase was derived as an averaged liquid viscous stress term and the relation for the fluctuating stress in laminar bubbly flow was given. A closed-two-fluid model was established to describe the flow. Comparison of the experimental data published in literature with the present model prediction showed that the present model can be applied to flows in a wider bubble size range due to the reasonable consideration of the near-wall effect.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2001年第10期902-906,共5页
CIESC Journal
基金
国家自然科学基金资助项目 (No .195 72 0 42 )~~
