Investigations on Heat-Transfer Fluids by means of Computer Simulations: Fokus on Ionic Liquids and Ionanofluids

该项目是通过计算机模拟对传热流体（HTFs）进行理论研究。在实际应用中，从冷却装置到太阳能收集，热传递函数的热物理性质，如热传导和热容，是至关重要的。对HTFs进行建模可以更深入地了解原子和分子水平上的底层机制，例如热传导。非平衡分子动力学（NEMD）的方法，打算在这里使用，通过明确的建模热梯度提供了额外的机会，研究耦合效应，如热泳。为了获得有关基础机制的详细知识，以及其对分子结构和组成的依赖性，以及对热物理性质的影响，对于HTFs的有目的设计至关重要。在这里，我们重点介绍离子液体（IL）和离子液体中的纳米颗粒悬浮液，所谓的离子纳米流体或纳米颗粒增强的IL（NEIL）作为HTFs。研究重点1关注纯离子液体和离子液体的不同阴离子或阳离子类型的影响，以及杂质的影响，如水、氯离子或有机溶剂，对热物理性质的影响。研究重点2是NEIL以及由于IL与纳米颗粒的相互作用而导致的额外效应和机制，这些效应和机制导致热导率显着增加，如实验所示。

The project is about theoretical investigations on heat-transfer fluids (HTFs) by means of computer simulations. In practical applications, from cooling devices to solar energy collection, the thermophysical properties of the HTFs, like heat conduction and heat capacity, are of crucial significance. Modeling the HTFs allows a deeper insight into the underlaying mechanisms, of for example the heat conduction, on an atomistic respectively molecular level. The non-equilibrium molecular dynamics (NEMD) method, intended to use here, provides through the explicit modeled thermal gradient additionally the opportunity to study coupling effects, like thermophoresis. To gain a detailed knowledge about the underlaying mechanisms, as well as whose dependency on molecular structure respectively composition, and the impact on the thermophysical properties, is vital for a purposive design of HTFs. Here we focus on ionic liquids (ILs) and suspensions of nano-particles in ionic liquids, so called ionanofluids or nano-particle-enhanced ILs (NEILs) as HTFs. Research focus 1 is concerned about pure ILs and the effect of different anion or cation types of the ILs and furthermore the influence of impurities, like water, chloride ions or organic solvents e.g., on the thermophysical properties. Research focus 2 is on NEILs and the additional effects and mechanisms due to the interactions of the ILs with nano-particles, which lead to the significant increase in thermal conductivity as it was shown in experiments.