在流場性質的討論中，Couette和Poiseuille等簡單流場是常常被討論和研究的，而在微觀流場中，壁面附近的流體密度震盪及其滑動現象是其和巨觀流場行為的兩大差異處。本文以分子動力學模擬類似壓力驅動下管徑為10個分子直徑和22個分子直徑之奈米流場，由分子位置分佈圖可清楚看出平板銅分子會吸引液態氬分子而形成類似吸附層的現象，而流場密度分佈圖也顯示壁面附近因平板吸附作用而產生之密度陡升的性質。又從流場速度分佈圖來看，當給定之驅動壓力較小與較大時，分別可以得到定性上層流拋物線分佈和紊流形式之速度分佈狀況；而當驅動壓力太大時，則會造成Lennard_Jones勢能模擬的不準確性。從各種速度分佈圖也可清楚的觀察到滑動現象，這也符合了Maxwell在動能理論中所預測的結果。
由本文的模擬結果看來，流場性質不但和流體種類與其勢能函數有關，且和平板分子勢能函數的種類有關。所以平板與流體之合適的勢能函數之選擇對模擬結果有很大的影響。

The flow field, like Couette and Poiseuille flow, are often adopted to discuss and study flow physics. Liquid density fluctuation near channel surface and the velocity slip at surface are two major differences between microscopic and macroscopic flow. In this paper, we use molecular dynamics simulation (MD) to simulate pressure-driven nano-channel flow, in which the widths of the pore are ten or twenty two times to the diameter of liquid Argon molecule. According to the particles distribution profile, we can see that Cu particles of the channel will attract liquid Argon molecules to form an adsorption layer near the channel. And from the density profile, it shows the sudden increase in density near channel boundary because of the adsorption interaction.
From the computed velocity profile, when setting small and large pressure force, we can obtain either the parabolic distribution in lamier flow or flat distribution in turbulence flow. But when the pressure force becomes too large, Lennard_Jones potential will be fail to simulate the flow field. Velocity slip is clearly observed in all velocity profiles in this work, and this result is confirmed by the Maxwell prediction in his Kinetic theory.
It can be concluded from this study that the properties of flow field are affected not only by the kind of liquids and its potential, but also by the potential function of the channel molecules. Correct choice of potential to channel and liquid particles plays an important role in simulation results.

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