Cui Xin, Wang Jun, Xia Guodong
Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, College of Energy and Power Engineering, Beijing University of Technology, Beijing 100124, P.R. China.
Nanoscale. 2021 Dec 23;14(1):99-107. doi: 10.1039/d1nr05630a.
The addition of nanoparticles to a base fluid (, nanofluids) is an effective strategy to achieve a higher thermal conductivity of a fluid. In a common nanofluid, the suspended nanoparticles are mostly symmetrical spheres. In the present paper, we propose to add Janus nanoparticles into a fluid (termed as Janus nanofluids), to further enhance the thermal conductivity of nanofluids. By using molecular dynamics simulations, it is found that the thermal conductivity can be distinctly improved by introducing Janus particles into the nanofluids in contrast with common nanofluids. Based on the calculation results of the molecular radial distribution function around the nanoparticle, and the diffusion coefficient of the base fluid and the Janus nanoparticle, the enhancement in the thermal conductivity of Janus nanofluids is attributed to the enhanced Brownian motion of Janus nanoparticles, which increases the probability of inter-molecular collisions and leads to enhanced energy transfer in nanofluids. The Janus nanofluids proposed in this work provide insights for the design of nanofluids with high thermal conductivity.
向基础流体中添加纳米颗粒（即纳米流体）是提高流体热导率的有效策略。在普通纳米流体中，悬浮的纳米颗粒大多是对称球体。在本文中，我们提议向流体中添加Janus纳米颗粒（称为Janus纳米流体），以进一步提高纳米流体的热导率。通过分子动力学模拟发现，与普通纳米流体相比，将Janus颗粒引入纳米流体中可显著提高热导率。基于纳米颗粒周围分子径向分布函数的计算结果，以及基础流体和Janus纳米颗粒的扩散系数，Janus纳米流体热导率的提高归因于Janus纳米颗粒布朗运动的增强，这增加了分子间碰撞的概率，并导致纳米流体中能量传递增强。这项工作中提出的Janus纳米流体为设计高导热率纳米流体提供了思路。
