医用CT在三维椭球颗粒随机堆积结构研究中的应用

Medical CT Application in the Study of 3D Random Packing of Ellipsoids

颗粒随机堆积问题是物理和工程领域的热门问题。椭球颗粒随机堆积体系作为球形体系的拓展,增加了旋转自由度,从而表现出更复杂的性质,由于椭球颗粒比球形颗粒更类似于自然界中普遍存在的非规则颗粒,因此其研究具有重要的实用价值。研究三维颗粒堆积结构问题一般需要CT成像技术,本文介绍了如何利用医用CT对三维椭球随机堆积体系进行成像研究的技术细节,包括如何通过图像处理的方法获取椭球颗粒的空间位置、取向和体积,如何利用接触数标度函数拟合的方法得到近邻颗粒间的接触信息等。本文的研究内容和方法为利用各种X射线CT成像方法研究三维颗粒体系提供了技术参考。

The particle random packing problem is important for both physics and engineering applications. The study of random ellipsoid packing, as the generalization of the spherical one, is difficult owing to the complexity introduced by the rotational degrees of freedom. However, the study of ellipsoid particle packing is more relevant to realistic applications since the ellipsoid shapes are closer to real particles in nature. Here we present the technical details of the application of medical CT for the study of three-dimensional ellipsoid random packings, e.g., how to obtain three-dimensional geometric information like positions, orientations, and volumes of ellipsoids by image processing techniques from the tomography data; how to extract the ellipsoids＇ contact information by scaling function analysis. This study provides useful technical information for the application of X-ray tomography technique on the study of the granular packing.