摘    要：纳米材料是组成结构大小为1nm到100nm之间的材料。目前全世界范围内对于纳米技术的研究都还在初级阶段，即使是美国、德国、日本等少数发达国家也只是具备一定的研究基础，近年来我国的研究也在慢慢发展，相关科研人员的队伍也在日益壮大，正在努力追赶世界上其他发达国家的研究水平。

我们通常使用各种物理定律来描述万物的产生和变化。自 20 世纪 40 年代以来，人们就致力于利用计算机来理解各种物理现象。最初的时候，由于计算资源非常稀缺，研究主要集中在各种孤立的物理效应。然而，我们现实世界中的物理现象并不是孤立发生的。现实世界在本质上是一个多物理场的世界。所以CFD即计算机流体力学应运而生，CFD是由独具各自功能的三个模块组成，分别是前处理，求解器和后处理。它可以把流体力学的实验进行数值模拟与计算机模拟并且还可以分析研究问题的同时去应用各种不同的离散化的数学方法。所以CFD可以说是由计算机科学、数学、以及流体力学所组成的新学科。这次实验就是在找到纳米材料扩散系数的方法下，建立正确模型的条件下进行研究。

扩散系数是由气体和固体所组合的性质所决定，从微观的角度来讲，任何固体材料的内部在气体扩散时都至少会进去一部分气体，而气体在固体中的扩散机制又和气体单独的扩散机制相同。所以本文通过研究纳米孔材料内部气体的扩散行为可以了解纳米孔材料内部不同参数对气体在材料内部扩散的影响，同时也可以了解改变材料外部环境的参数对气体在材料内部扩散的影响。通过这些研究可以更深刻的了解纳米孔材料的相关性能，研究孔隙率，样品宏观尺寸，边界条件对气体在纳米孔材料内部扩散的影响，孔隙率越大样品到达平衡时的压强越大，初始压强到平衡压强的变化量越小；体积越大到达平衡压强时的变化量越大，到达平衡时的压强越小，到达平衡的时间越长；边界压强越大样品到达平衡时的压强越大，到达平衡的时间越长。通过这些发现可以在以后的实验研究中更好的利用纳米材料的性能。对于未知固体材料，研究气体在其内部的扩散系数可以从物理性质这方面来了解它的结构、属性，这将影响到材料科学以及相关工程领域的研究发展。

关键词： 纳米材料；数值模拟；气体扩散；多孔介质；CFD

Abstract：Nanomaterials are materials with a compositional size of between 1 nm and 100 nm. At present, research on nanotechnologies is still in its infancy around the world. Even the developed countries such as the United States, Germany, and Japan have only a certain amount of research basis. In recent years, research in our country has also been slowly developing. The team is also growing and it is trying to catch up with the research level of other developed countries in the world.

We often use various physical laws to describe the production and changes of all things. Since the 1940s, people have devoted themselves to using computers to understand various physical phenomena. Initially, due to the scarcity of computing resources, research has focused on a variety of isolated physical effects. However, the physical phenomena in our real world do not occur in isolation. The real world is essentially a multi-physics world. Therefore, CFD, ie, computer fluid mechanics came into being. CFD is composed of three modules with their own functions, namely, pre-processing, solver and post-processing. It can carry out numerical simulations and computer simulations of fluid mechanics experiments and can also apply various discretized mathematical methods while analyzing research problems. So CFD can be said to be a new discipline composed of computer science, mathematics, and fluid mechanics. This experiment was conducted under the conditions of establishing the correct model under the method of finding the diffusion coefficient of nanomaterials.