在蒸汽切割流中,在超疏水表面的凝结过程中,滴落动力学
Shaur Humayun1, R Daniel Maynes1, Julie Crockett1
1Brigham Young University, Provo, Utah 84602, United States.
Langmuir : the ACS journal of surfaces and colloids
|January 24, 2025
概括
控制超疏水 (SH) 表面的滴量是有效的冷凝热传递的关键. 这项研究表明,较低的固体分数和较高的空气流量可以减少最大滴出口大小,从而提高凝结性能.
科学领域:
- 凝结热传递 凝结热传递
- 表面科学是一门学科.
- 流体动力学 流体动力学
背景情况:
- 准确的下降动态模型对于在超 (SH) 表面的热传递估计至关重要.
- 之前的研究主要集中在SH表面的重力或蒸汽流的影响上.
- 表面特征在凝结过程中对滴流动性的影响需要进一步研究.
研究的目的:
- 为了研究表面固体分数和纹理尺度对凝结过程中的滴流动性的影响.
- 分析潮湿空气流对下降动态和离开大小的影响.
- 开发调SH表面以控制掉落行为的方法.
主要方法:
- 涉及在SH表面上凝结的实验,具有微到纳米尺度的特征.
- 视频分析以确定下降尺寸分布和最大下降起点尺寸.
- 粒子图像速度测量 (PIV) 用于量化剪切力和跳跃距离.
主要成果:
- 随着表面固体分数的降低和流速的增加,最大下降偏离尺寸下降.
- 凝聚力诱导的跳跃被确定为跳跃起落的关键机制.
- 当结合的水滴大小相似时,跳跳距离会增加.
- 用Bond和毛细管数量化的落下移动性取决于表面固体分数和距离尺寸,与表面滑动长度相关.
结论:
- 表面固体分数和空气流量是控制滴出点大小的关键参数.
- 调整SH表面特征,如固体分数和斜率,可以优化掉落的移动性和离开.
- 了解滴凝聚和跳跃行为对于在SH表面设计高效的凝结系统至关重要.
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