基于羟基化Janus碳纳米管的纳米流体导热特性  

Thermal conductivity of nanofluids based on hydroxylated Janus carbon nanotubes

作　　者：李康睿 王军[1] 夏国栋[1] LI Kangrui;WANG Jun;XIA Guodong(Beijing Key Laboratory of Heat Transfer and Energy Conservation,College of Mechanical and Energy Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学机械与能源工程学院,传热与能源利用北京重点实验室,北京100124

出　　处：《物理学报》2025年第6期153-160,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12472268)资助的课题.

摘　　要：碳纳米管本身所具有的卓越导热性能,使得基于碳纳米管所制备的纳米流体也同样具有较高的热导率,同时在碳纳米管表面添加官能团能够有效增强水/碳纳米管纳米流体的稳定性.本文将羟基化碳纳米管构建成为Janus颗粒,基于平衡分子动力学模拟方法,计算了基于羟基化碳纳米管的纳米流体热导率,并对其导热机理进行分析.计算结果表明,在基液吸附层密度增长、颗粒布朗运动增强以及界面热阻降低等因素的共同作用下,基于羟基化碳纳米管的纳米流体具有比普通碳纳米管纳米流体更强的导热性能.羟基化碳纳米管构建的Janus颗粒在基液中具备更强的布朗扩散能力,因而可以进一步提高水/碳纳米管纳米流体的热导率.本文揭示了基于羟基化Janus碳纳米管的纳米流体导热机理,为新型传热工质制备提供参考.The excellent thermal conductivity of the carbon nanotubes leads to the high thermal conductivity of the nanofluids prepared by carbon nanotubes.The addition of functional groups on the surface of the carbon nanotubes canimprove the stability of the water/CNT nanofluids.The excellent diffusion properties of the Janus particles result in the elevated thermal conductivity of the Janus nanofluids.In thiswork,hydroxylated single-walled carbon nanotube(SWCNT-OH)particles,as Janus particles,are constructed and a water/SWCNT-OH-Janus nanofluid model is proposed by introducing SWCNT-OH particles into a base fluid(water).By using equilibrium molecular dynamics simulations,the thermal conductivity of nanofluids is calculated.The mechanism of the enhanced thermal conductivity is investigated by analyzing the solid-like liquid layers formed by liquid molecules around particles,Brownian motion of CNT particles,and CNT/water interfacial thermal resistance.It can be concluded that the thermal conductivity of the nanofluids with SWCNT-OH particles can be enhanced compared with that of the nanofluids with normal SWCNT particles.The hydrogen bond between hydroxyl group and water molecules results in the adsorption of water molecules onto the surface of carbon nanotube.This process increases the density of the liquid adsorption layer on the CNT surface,thereby enhancing the effect of the solidliquid layer.The hydroxyl groups on the CNT surface degrade the solid-liquid interfacial thermal resistance,which promotes the heat transfer within the nanofluids.Moreover,the hydroxyl groups also enhance the interaction between the CNT particles and the water molecules,leading to stronger Brownian motionof particles.The combination of these factors will be responsible for the enhancement thermal conductivity of the water/SWCNT-OH nanofluids.For SWCNT-OHJanus nanofluids,the thermal conductivity can be further enhanced,owing to the strong Brownian motion of the Janus particles.

关 键 词：纳米流体 碳纳米管 JANUS 颗粒 羟基 分子动力学模拟 

分 类 号：TB3[一般工业技术—材料科学与工程]