A prediction of drag reduction by entrapped gases in hydrophobic transverse grooves
A prediction of drag reduction by entrapped gases in hydrophobic transverse grooves
复制标题
疏水横向凹槽中截留气体减阻的预测
DOI：
10.1007/s11431-013-5395-y
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发表时间：
2013-10
期刊：
影响因子：
--
通讯作者：
Chen DaRong
中科院分区：
文献类型：
--
作者：
Wang Bao;Wang JiaDao;Chen DaRong
超疏水表面的减阻效果是不稳定的，因为被困气体会逐渐消失。本文设计了一种疏水横向沟槽表面，以维持山谷中的气体。通过数值模拟研究了该表面附近的流场.当水流过该表面时，气阱中的气体被气脊阻挡，气阱中的气体将气-固界面置换为气-固界面，并在气-固界面处形成微涡旋。由于气固两相之间存在有效的滑移，边界层速度梯度减小，减阻效果显著。此外，考虑到附加压力减阻对减阻效果的负面影响，对包括粘性阻力系数和压力系数在内的总阻力系数进行了分析。在高速水洞中进行的实验证实了该方法的有效减阻率约为15%。
The drag reduction effect of super-hydrophobic surface induced by the entrapped gas is unstable due to the gradual disappearance of the trapped gas. In this paper, a hydrophobic transverse grooved surface was designed to sustain gas in valleys. A detail numerical simulation was presented to investigate the flow field near the proposed surface. When water flowed over this surface, the entrapped gas was blocked by the ridges and the solid-liquid interface was replaced by the liquid-gas interface due to the entrapped gas, furthermore the micro-vortex formed in the groove. Because there was an effective slippage between water and solid induced by the entrapped gas, the velocity gradient of boundary layer decreased, which contributed to a remarkable drag reduction effect. Additionally, considering the extra undesired pressure drag reduction which negatively impacted the drag reduction effect of this method, the total drag coefficient including the viscous drag coefficient and the pressure coefficient was analyzed. An effective drag reduction rate of about 15% was achieved and the effect of this method was confirmed by experiments conducted in a high-speed water tunnel when grooves were optimized.
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DOI：
10.1021/la2027412
发表时间：
2011-07
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
--
作者：
N. Kumari;S. Garimella
通讯作者：
N. Kumari;S. Garimella
稀表面活性剂溶液流减阻机理实验研究
DOI：
10.1016/j.ijheatmasstransfer.2007.04.048
发表时间：
2008-02
影响因子：
5.2
作者：
Hishida, Koichi;Yu, Bo;Kawaguchi, Yasuo;Wei, Jin-Jia;Li, Feng-Chen
通讯作者：
Li, Feng-Chen
DOI：
10.4314/ijest.v3i2.68680
发表时间：
2011-07
期刊：
International journal of engineering science and technology
影响因子：
--
作者：
Pritanshu Ranjan;A. Ranjan;A. Singh
通讯作者：
Pritanshu Ranjan;A. Ranjan;A. Singh
影响因子：
3.7
作者：
Martell, Michael B.;Perot, J. Blair;Rothstein, Jonathan P.
通讯作者：
Rothstein, Jonathan P.
影响因子：
--
作者：
Deyuan Zhang;Yuanyue Li;Xin Han;Xiang Li;Huawei Chen
通讯作者：
Deyuan Zhang;Yuanyue Li;Xin Han;Xiang Li;Huawei Chen