在高静态压力下的液体注入表面上减少流体滑动和拖动
Christopher Vega-Sánchez1,2,3, Chiara Neto2,3
1School of Electromechanical Engineering, Costa Rica Institute of Technology, Cartago 159-7050, Costa Rica.
Langmuir : the ACS journal of surfaces and colloids
|February 15, 2024
概括
液体注入表面 (LIS) 减少微流体阻力,但压力会影响性能. 在气化水中,LIS上的纳米泡在压力下压缩,减少阻力减小,与最初预期的不同.
科学领域:
- 流体动力学 流体动力学
- 表面科学是一门学科.
- 材料科学 材料科学 材料科学
背景情况:
- 液体注入表面 (LIS) 具有降低微流体流动中的摩擦阻力潜力.
- 理论上,LIS由于不可压缩的滑剂,比超水表面更具压力强度.
- 了解压力对LIS的影响对于其实际的微流体应用至关重要.
研究的目的:
- 为了研究静态压力对液体注入的特龙纹表面有效滑动长度的影响.
- 为了比较LIS的压力灵敏度与微流体流动中的超疏水性纹表面.
- 阐明空气含量和纳米气泡在LIS上观察到的压力效应中的作用.
主要方法:
- 制造的特龙纹表面注入油.
- 在不同静态压力 (0-200 kPa) 的微流体装置中测量有效滑动长度 (b_eff).
- 用脱气和气化水进行实验,以评估空气含量的影响.
主要成果:
- 对于脱气水,无论施加的压力如何,LIS表现出一致的有效滑动长度 (2.16 ± 0.90 μm).
- 在气化水中,LIS显示有效滑动长度 (55%) 从0.0kPa时的4.32±1.06μm显著减少到50kPa时的2.37±0.90μm,随后稳定.
- 超水表面表现出更大的压力敏感性,有效滑动长度从0.0kPa的6.8±1.4μm急剧下降到50kPa以上的-1±3μm,表明阻力显著增加.
结论:
- 与预期相反,施加的压力显著影响LIS的阻力减小,特别是在气化水中.
- 在LIS中观察到的压力依赖性归因于表面纳米泡的压缩或溶解.
- 无论是LIS还是超疏水表面,都可能在压力下失去滑界面气体,从而影响流动动力学.
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