在存在界面质量转移的情况下,滴滴形成的动态
Muzammilanwar S Khan1,2, Amol A Kulkarni1,2
1Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Pune 411008, India.
Langmuir : the ACS journal of surfaces and colloids
|August 25, 2023
概括
界面质量转移显著改变了滴水形成的动态. 更高的溶解物度会导致不稳定性,导致非轴对称的形状和多重滴滴生成,影响滴滴大小和形成时间.
科学领域:
- 流体动力学 流体动力学
- 接口现象 接口现象
- 质量转移是指质量转移.
背景情况:
- 了解滴水形成对于各种工业过程至关重要.
- 界面质量转移可以显著影响界面上的流体动力学.
- 以前的研究往往简化或忽略了滴形成过程中质量转移的动态效应.
研究的目的:
- 为了研究在界面质量转移下滴形成的实时动态.
- 分析不同溶解物度对滴形和脱落的影响.
- 开发和验证一个预测这些现象的模型.
主要方法:
- 控制的流量可视化实验使用n-hexane/乙混合物作为分散相和水作为连续相.
- 最初溶解物度的系统变化.
- 开发一个不稳定的力量平衡模型,以捕捉实时动态.
- 对模型预测与实验观测的验证.
主要成果:
- 观察到基于初始溶液度 (φ0) 的滴水形成模式的急剧转变.
- 在低φ0 (<0.2) 时,轴对称滴形成,质量转移效应微不足道.
- 中间的φ0 (0.2-0.5) 触发了马兰戈尼的不稳定性,导致了接口变形.
- 高的φ0 (>0.5) 导致非轴对称的形状,羽毛喷射和多个较小的滴滴生成.
结论:
- 交界溶液转移极大地影响了滴状形成的动态,尤其是在更高度下.
- 马兰戈尼的不稳定性和不平衡效应随着溶液梯度的增加而变得占主导地位.
- 构成变化,流体特性和界面不稳定性之间的相互作用决定了滴量大小和形成时间.
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