Scaling of the angle of repose test and its influence on the calibration of DEM parameters using upscaled particles
Scaling of the angle of repose test and its influence on the calibration of DEM parameters using upscaled particles
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DOI：
10.1016/j.powtec.2018.01.044
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发表时间：
2018-05-01
影响因子：
5.2
通讯作者：
Katterfeld, Andre
中科院分区：
文献类型：
--
作者：
Roessler, Thomas;Katterfeld, Andre
基于离散单元法（DEM）的计算机模拟的数值努力迫使DEM模型的理想化，特别是在分析工业问题时。理想化通常包括颗粒尺寸的放大，因此需要调整接触模型参数以产生逼真的模拟结果。因此，接触参数的标定是DEM模型开发过程中最关键的部分。由于颗粒尺寸的放大，校准测试应提供不随测试尺寸和颗粒尺寸变化的结果。本文展示了如何一个典型的校准测试的结果，休止角（AoR）测试使用升降缸，是不变的试验台的尺寸和所考虑的partide大小分布。圆柱体的提升速度被表示为影响AoR的参数。因此，当施加缓慢的提升速度时，圆柱体上拉试验仅提供静态应力状态下材料的尺寸不变结果。所谓的剪切盒试验将作为一种替代AoR试验，即使在动态、快速流动应力状态和短试验持续时间下也能获得不变的结果。(C)2018爱思唯尔B.V.保留所有权利。
The numerical effort of computer simulations based on the Discrete Element Method (DEM) forces an idealisation of the DEM models especially when industrial problems are analysed. The idealisation often includes the scale-up of the particle sizes and therefore requires the adaption of contact model parameters to produce realistic simulation results. Hence, the calibration of contact parameters is the most crucial part in the development process of a DEM model. Due to the scale-up of particle size, a calibration test should provide results invariant to test dimensions and particle size. This paper shows how the results of one typical calibration test, the angle of repose (AoR) test using a lifting cylinder, are invariant regarding the dimensions of the test rig and the considered partide size distribution. The lifting velocity of the cylinder is indicated as a parameter which influences the AoR Hence, the cylinder pull-up test delivers only size invariant results for materials in static stress state when slow lifting velocities are applied. The so called shear box test will be presented as an alternative AoR test to achieve invariant results even for a dynamic, fast flowing stress state and short test durations. (C) 2018 Elsevier B.V. All rights reserved.