DEM parameter calibration of cohesive bulk materials using a simple angle of repose test
DEM parameter calibration of cohesive bulk materials using a simple angle of repose test
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DOI：
10.1016/j.partic.2018.08.005
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发表时间：
2019-08-01
期刊：
影响因子：
3.5
通讯作者：
Katterfeld, Andre
中科院分区：
文献类型：
--
作者：
Roessler, Thomas;Katterfeld, Andre
离散元法（DEM）模拟的数值工作的结果在DEM模型的一般理想化，使校准获得逼真的模拟结果至关重要。休止角试验已成为标定无粘性散料DEM参数的标准试验，并在文献中得到广泛讨论。最常用的测试方法之一是填充散装材料的空心圆柱体的拉拔测试。本文介绍了如何通过改变分析标准，这种基本的拔出试验也可以用于粘性材料的DEM参数的校准。与静态休止角的分析相反，重点在于气缸提升过程中的宏观流动行为。在实验中确定了可再现的流动阶段：建立一个稳定的散装材料柱，柱的凸弯曲，和柱的崩溃开始。此外，相位与尺寸和提升速度无关。提出了一种新的可测量的标定准则，即散料柱的外凸弯曲和首次倒塌力矩。湿砂的这些实验结果用于使用简化的JKR凝聚力模型的相关DEM参数的校准。DEM校准包括适合实验流动行为的分析算法和相关参数的最终选择（即，滑动摩擦系数、滚动摩擦系数和粘聚力密度）。(C)2019中国科学院颗粒学会、过程工程研究所。Elsevier B.V.出版，保留所有权利。
The numerical effort of discrete element method (DEM) simulations results in a general idealisation of DEM models that makes the calibration crucial to obtaining realistic simulation results. The angle of repose test has become a standard test for the calibration of DEM parameters of cohesionless bulk materials and is extensively discussed in the literature. One of the most used test methods is the pull-up test of a hollow cylinder filled with bulk material. This paper presents how this basic pull-up test can also be used for the calibration of DEM parameters of cohesive materials by changing the analysis criteria. In contrast to analysing the static angle of repose, the focus lies on the macroscopic flow behaviour during the lifting of the cylinder. Reproducible phases of flow are identified in experiments: the build-up of a stable bulk material column, the convex bending of the column, and the beginning of collapse of the column. Furthermore, the phases are independent of the size and lifting velocity. The convex bending of the bulk-material column combined with the moment of first collapse are introduced as new measurable calibration criteria. These experimental results of wet sand are used for the calibration of related DEM parameters using a simplified JKR cohesion model. The DEM calibration including an analysis algorithm that fits the experimental flow behaviour and the final selection of the relevant parameters (i.e., sliding friction coefficient, rolling friction coefficient, and cohesion energy density) is presented in detail. (C) 2019 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.