本研究主要以非平衡態分子動力學（NEMD）模擬方法，研究探討介面熱阻對NEMD模擬計算奈米碳管熱傳行為時的影響，並重新檢視碳管尺寸效應造成的熱傳導係數與長度關係，與各種質量梯度之奈米碳管的熱傳行為。本文首先介紹非平衡態分子動力學模擬方法與逆向非平衡態分子動力學（rNEMD）模擬方法。而後利用改變控溫層原子質量，達到改變控溫層與自由層間的介面熱阻大小，藉此判斷介面熱阻對使用NEMD模擬計算奈米碳管熱傳導係數的影響，並透過熱阻與長度關係觀察碳管尺寸效應。又以非平衡態模擬法與逆向非平衡態模擬法計算文獻中質量梯度奈米管模型，進而修改模型找出適合探討質量梯度奈米管熱傳行為的模型與模擬方式，最後利用非平衡態模擬法比較不同半徑與長度的質量梯度奈米管的熱傳行為，並利用態密度解釋其熱整流效果。
本研究發現使用NEMD模擬計算碳管熱傳導係數時，會因為NEMD模擬產生的介面熱阻而影響，並透過比對文獻與修正後質量梯度奈米管的模型與模擬後，確認質量梯度奈米管具有熱整流效果，且為熱流方向由重原子往輕原子方向的熱傳導係數較反方向來的大。

The influence of interface thermal resistance on the thermal transfer behavior of carbon nanotubes (CNTs), and mass-graded CNTs were investigated using non-equilibrium molecular dynamics (NEMD) simulation method. First, we introduced NEMD and reverse non-equilibrium molecular dynamics (rNEMD) simulation methods. Then, we compared the influence of different interface thermal resistance between thermostat slabs and free slabs by altering the atomic mass of thermostat slabs, and observed the relationship between the thermal resistance and the length of CNTs. Moreover, the NEMD and rNEMD simulation were used to calculate the mass-graded CNTs model. We modified the model to choose appropriate model and simulation method to simulation. Finally, we observed the thermal transfer behavior of mass-graded CNTs with different length and diameter in different heat current direction, and explained the thermal rectification by density of state (DOS).
In this study, we found out thermal conductivity of CNTs calculated by using NEMD simulation was influenced by interface thermal resistance, mass-graded CNTs had thermal rectification, and thermal conductivity of mass-graded CNTs is higher when heat current direction is from the heavy-mass to the light-mass region.

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