氧化石墨烯表面的气泡动力学及传热实验

Bubble dynamics and heat transfer experiments on graphene oxide surface

采用氧化石墨烯(GO)纳米片沸腾自组装法制备GO纳米涂层表面,考察表面改性对传热性能、近壁面流场行为和气泡动力学参数的影响。结果表明,GO纳米涂层表面的强化换热效果明显,临界热流密度(CHF)达到211.2 W/cm^(2),换热系数(HTC)达到8.12 W/(cm^(2)·K),与光滑铜表面相比,分别提高了89.7%和75.9%,GO纳米涂层表面上的气泡脱离直径小,脱离频率高,成核位点多,近壁面的流场更复杂,对流传热更明显。

Graphene oxide(GO)nanocoated surface is prepared through boiling self-assembly of graphene oxide nanosheets.The impact of surface modification on the heat transfer performance,near-wall flow field behavior and bubble kinetic parameters are examined.The experimental results show that GO nano-coated surface has an obvious enhanced heat transfer effect,and its critical heat flow density(CHF)and heat transfer coefficient(HTC)can reach 211.2 W·cm^(-2)and 8.12 W·cm^(-2)·K^(-1),respectively,which are 89.7%and 75.9%higher than the smooth copper surface.It is found that the bubbles on GO nano-coated surface have small detachment diameter,high detachment frequency,and many nucleation sites.The convective heat transfer is more pronounced as the flow field near the wall on the GO nanocoated surface is more complex.