金智敏;周宏伟;薛东杰;

• 1:中国矿业大学(北京)力学与建筑工程学院

摘要(Abstract)：

为实现基于CT图像的煤岩孔隙度和比表面积快速测量,提出了一种基于MATLAB图像处理的测量方法。以平煤十二矿深部采集的煤岩为研究对象,应用Nano CT技术对样品进行了扫描,并分别借助Avizo和MATLAB软件计算孔隙度和比表面积,研究了Avizo三维建模和MATLAB图像处理2种方法的优缺点。发现2种方法计算出的结果误差仅在10%左右,且以复合Cotes公式的误差估计最小,孔隙度和比表面积的误差分别为9. 392%和8. 247%.结果表明:传统的基于Avizo三维建模的测量方法精确度较高,同时还能获取样品的三维孔隙网络模型和孔隙的形状、走向及孔径分布,但计算过程复杂,对于复数个试样必须进行多次计算,且对CT图像有较高的质量要求。基于MATLAB图像处理的测量方法则通过简单的数值积分实现了快速计算煤岩的孔隙度和比表面积,避免了三维建模,极大地降低了计算复杂度,且能够一次性处理复数个试样,较好地满足了实际工程需要。且对于CT图像具有更高的容错率,每次计算仅需其中数张扫描质量效果较好的CT图像即可。

关键词(KeyWords)： 煤岩;CT图像;孔隙度;比表面积;MATLAB;Avizo

Abstract:

Keywords:

基金项目(Foundation): 国家重点研发计划(2016YFC0600704);; 国家自然科学基金(51504257)

作者(Author): 金智敏;周宏伟;薛东杰;

Email:

DOI: 10.13800/j.cnki.xakjdxxb.2020.0118

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