...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Surface Science >The impalement of water drops impinging onto hydrophobic/superhydrophobic graphite surfaces: the role of dynamic pressure, hammer pressure and liquid penetration time
【24h】

The impalement of water drops impinging onto hydrophobic/superhydrophobic graphite surfaces: the role of dynamic pressure, hammer pressure and liquid penetration time

机译：水滴对撞击疏水/超疏水石墨表面的影响：动压力，锤击压力和液体渗透时间的作用

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Droplet impingement experiments at low Weber numbers were conducted by digitizing silhouettes of impacting water drops onto unlike graphite substrates, typified by different advancing water contact angles (θ_α): 140 and 160°. The relaxation of wetting diameter, dynamic contact angle, and drop shapes were measured. The purpose was to carefully investigate the phenomenology and possible causes of the failure of the superhydrophobicity. During impact and spreading phases, all the drops impinging onto both graphite substrates showed a similar behavior. Then, after an initial free recoil, drops impinging at lower impact velocities onto graphite substrates characterized by θ_α = 140° clearly exhibited time intervals in which the wetting diameter appeared to be almost constant. The duration of this pinned phase was observed decreasing with increasing the impact height and almost completely disappearing for drops impinging at higher impact velocities. This behavior has never been reported before, and, contrariwise, water droplets impinging at lower impact velocities onto hydrophobic and superhydrophobic surfaces have been generally observed more freely retracting, and ultimately rebounding, compared to drops impacting at higher velocities. In the present study, this latter behavior was recorded just for drops impinging onto graphite surfaces characterized by θ_α = 160°. A theoretical description of the experimental results was proposed, specifically investigating the role of dynamic pressure, hammer pressure and liquid penetration time during the impact, spreading and recoil stages.
机译：通过将撞击水滴的轮廓数字化到不同的石墨基材上（以不同的前进水接触角（θ_α）：140和160°为代表），进行了低Weber数的液滴撞击实验。测量润湿直径，动态接触角和液滴形状的松弛。目的是仔细研究超疏水性失效的现象学和可能的原因。在撞击和铺展阶段，撞击到两个石墨基体上的所有液滴均表现出相似的行为。然后，在初始的自由反冲之后，以较低的撞击速度撞击到以θ_α= 140°为特征的石墨基板上的液滴清楚地显示出时间间隔，其中润湿直径似乎几乎恒定。观察到该固定阶段的持续时间随着冲击高度的增加而减小，并且对于以较高冲击速度撞击的液滴几乎完全消失。以前从未报道过这种行为，相反，与较高速度的水滴相比，以较低的撞击速度撞击水滴和超疏水表面的水滴通常更自由地缩回，最终反弹。在本研究中，仅针对撞击到以θ_α= 160°为特征的石墨表面的液滴记录了后一种行为。提出了实验结果的理论描述，特别是研究了动态压力，锤击压力和液体渗透时间在撞击，扩散和反冲阶段的作用。

著录项

  • 来源
    《Applied Surface Science》 |2014年第15期|515-524|共10页
  • 作者

    Paola G. Pittoni; Ya-Chi Lin; Shi-Yow Lin;

  • 作者单位

    Department of Chemical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Taipei 106, Taiwan, ROC;

    Department of Chemical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Taipei 106, Taiwan, ROC;

    Department of Chemical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Taipei 106, Taiwan, ROC;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    Drop impact; Superhydrophobicity; Sticky drops; Penetration time; Impalement; Pinning;

    机译：跌落冲击;超疏水性粘性滴剂;渗透时间;穿刺固定;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号