表面张力对通过纠正扩散泡生长的作用
1School of Mathematics, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Ultrasonics sonochemistry
|June 18, 2023
概括
表面活性剂通过改变表面张力显著增强声化学中的泡生长,而不是主要通过微流或低度的质量转移阻力. 这一发现影响了超声波清洁和医疗超声波的应用.
科学领域:
- 声学腔化是一种声学腔化.
- 物理化学 物理化学
- 流体动力学 流体动力学
背景情况:
- 纠正扩散对于声化学,超声波清洁和医疗超声波至关重要.
- 已知表面活性剂可提高这些应用中的泡生长率.
- 以前的假设将这种增强归因于声学微流和质量转移阻力.
研究的目的:
- 调查二甲基硫酸盐 (SDS) 度在正扩散中的泡生长中的作用.
- 模拟表面活性剂引起的表面张力变化对气泡动态的影响.
- 挑战现有的关于表面活性剂增强泡增长的主导机制的假设.
主要方法:
- 利用基于多尺度和匹配的非对称扩张方法的新型可处理模型.
- 在数百万个振荡周期中模拟泡生长.
- 专注于由于SDS的表面张力系数的变化.
主要成果:
- 准确预测了SDS度高达2.4毫米的实验泡增长率.
- 已经证明,由表面张力驱动的外和面积效应在较低的SDS度下占主导地位.
- 显示声微流和质量转移阻力仅在较高的SDS度下变得显著.
结论:
- 表面张力变化在水性表面活性剂溶液的整形扩散中发挥的作用比以前认为的更为关键.
- 主要的机制是表面张力驱动的外和面积效应在低SDS度.
- 气泡增长速度对半径变化的敏感性可能解释了声化学应用中的不可预测性.
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