The hard sphere model was used to describe inter-particle collisions.

采用硬球模型描述颗粒间的碰撞作用。

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The density profile of hard sphere fluid confined in two parallel hard walls was studied by using Rosenfeld density Functional Theory (DFT) and Molecular Dynamics (MD) simulation method.

利用密度泛函理论和分子动力学方法，对处于两平行硬墙之间的硬球流体的密度分布进行了计算。

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The discrete element method (DEM) is introduced, which includes hard sphere model and soft sphere model.

着重介绍了非连续介质模型中的离散元法(dem)：硬球模型和软球模型。

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There's the hard sphere. It wants to collide against the wall to create a force on the wall, and I have a couple of the hard spheres that are nearby, right, and in the absence of any interactions, I get a certain pressure.

给墙一个作用力,现在它的附近，还有许多小球,没有相互作用时,它将直接冲向这面墙。

麻省理工公开课 - 热力学与动力学课程节选

OK, that's the hard sphere volume of the spheres.

有着相互作用力。

麻省理工公开课 - 热力学与动力学课程节选

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