在許多奈米科學的理論中，已經發現到許多物質在微小的尺寸下，所呈現出的各種物理及材料特性將與一般傳統巨觀的認知有所不同。例如，物質在奈米尺寸下，電子的傳輸特性及平均自由路徑將與巨觀時有所不同並產生量子尺度效應及電子相干效應。因此，為了了解在微觀的尺寸下，流體相關的各種熱力學性質及傳輸性質是否可能與巨觀比較而有所改變做一些探討。
本研究首先以分子動力學理論結合統計熱力學來探討液態氬在NVE系統下模擬得到的各種熱力學性質及傳輸性質，並將其結果與實驗所獲得的數據做比較。最後並在液態氬中加入白金粒子，探討其熱傳導係數及黏滯係數隨白金濃度的變化情形。為了簡化起見，我們僅在定性上討論奈米流體的熱傳趨勢。結果顯示，若白金分子在液態氬分子中比例佔很少時，奈米液體的熱傳特性將遠優於由於黏滯係數增加所造成的負面影響。反之，若白金分子在液態氬分子中所佔有的比例愈大時，則奈米液體黏滯係數增加所造成的負面影響將大於熱傳導係數增加所帶來的優點。我們在比較熱傳導係數與黏滯係數關係時也發現到在稀薄奈米流體當中，其熱傳導係數增加率最高約為黏滯係數的3倍。這些結果和目前以水為主的奈米流體實驗中，熱傳導係數與黏滯係數的變化定性上是雷同的。

The thermodynamic properties such as viscosity and thermal conductivity, that depend on the pressure and temperature of system, are important in the analysis of heat transfer. To predict these properties becomes possible by the method of molecular dynamics because the fluid is basically composed of a collective of molecules from a microscopic point of view.
The understanding and treatment at a molecular level have been recognized to be more important in heat and mass transfer research recently. A new field, “Molecular Dynamic Engineering,” has a variety of applications in the future development of microscopic heat transfer theory and in handling the heat transfer situations related to nano- technology. The traditional concepts of flow field and heat transfer may not be applied in nanofluids. Therefore, to analyze the basic properties of nanofluids such as the viscosity and thermal conductivity is very important. The thermodynamic properties of the pure liquid argon and the nanofluid, composed of liquid argon and solid platinum, are calculated numerically by the method of molecular dynamics. The thermal conductivity and viscosity of the pure liquid argon and the nanofluid are obtained, respectively. Quantitatively, the data of pure liquid argon are in good agreement with the experimental results. In addition, the qualitative behaviors of common nanofluids can be satisfactorily described according the results in this work.

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