Thermal transport dynamics in active heat transfer fluids (AHTF)
Thermal transport dynamics in active heat transfer fluids (AHTF)
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DOI：
10.1063/5.0047283
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发表时间：
2019-05
影响因子：
3.2
通讯作者：
W. Peng;A. Chandra;P. Keblinski;J. Moran
中科院分区：
文献类型：
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作者：
W. Peng;A. Chandra;P. Keblinski;J. Moran
我们目前的分子动力学计算的有效导热系数的纳米流体含有自推进纳米粒子的结果。在模拟中观察到的平移和旋转动力学遵循布朗和自推进纳米颗粒的标准理论分析所预期的行为。自推进和旋转布朗运动的叠加导致自推进纳米颗粒的行为类似于布朗扩散，其有效扩散率比标准布朗值大几千倍。由于增强的扩散（和对流混合产生的运动），我们观察到一个可辨别的增加的有效热导率的溶液含有自推进纳米粒子。虽然我们观察到的增加在几个百分比的范围内，但考虑到在没有推进的情况下，纳米流体的热导率基本上不受布朗运动的影响，并且可以在热传导的有效介质理论中理解，它们是重要的。我们的研究结果构成了一个概念证明，即自推进颗粒有可能提高它们所浸入的液体的导热性，这一想法最终可以在各种各样的冷却应用中实现。
We present results of molecular dynamics calculations of the effective thermal conductivity of nanofluids containing self-propelled nanoparticles. The translational and rotational dynamics observed in the simulations follow the behavior expected from the standard theoretical analysis of Brownian and self-propelled nanoparticles. The superposition of self-propulsion and rotational Brownian motion causes the behavior of the self-propelled nanoparticles to resemble Brownian diffusion with an effective diffusivity that is larger than the standard Brownian value by a factor of several thousand. As a result of the enhanced diffusion (and the convective mixing resulting from the motion), we observe a discriminable increase of the effective thermal conductivity of the solution containing self-propelled nanoparticles. While the increases we observe are in the range of several percent, they are significant considering that, without propulsion, the nanofluid thermal conductivity is essentially not affected by the Brownian motion and can be understood within the effective medium theory of thermal conduction. Our results constitute a proof of concept that self-propelled particles have the potential to enhance thermal conductivity of the liquid in which they are immersed, an idea that could ultimately be implemented in a broad variety of cooling applications.