Development and validation of calibration methods for discrete element modelling
Development and validation of calibration methods for discrete element modelling
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DOI：
10.1007/s10035-010-0197-4
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发表时间：
2011-04
期刊：
影响因子：
2.4
通讯作者：
Andrew P Grima;P. Wypych
中科院分区：
文献类型：
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作者：
Andrew P Grima;P. Wypych
离散单元法(DEM)已被证明是研究和预测颗粒材料行为的一种可靠且日益广泛使用的工具。许多颗粒尺度的机制影响着散装材料的散装行为和流动。重要的是，离散元模型的相关可测量输入参数应由实验室设备测量或由物理校准实验确定，以获得合理的结果。本文描述了一些实验室规模的实验，这些实验是为了校准DEM模拟以反映实际的动态行为。为了模拟干湿颗粒材料的散体行为，研究了相关参数，如静摩擦系数、滚动摩擦系数、恢复系数和液桥作用下颗粒间的内聚力。为了验证DEM模型，将结果与试验坍落度试验和漏斗出流试验进行了对比，以定量比较静止和固体质量流量的倾角和排水角。所提出的校准技术具有按比例模拟和微调不同长度尺度的颗粒材料的DEM参数的能力，以获得等效的静态和动态行为。
Discrete element method (DEM) is proving to be a reliable and increasingly used tool to study and predict the behaviour of granular materials. Numerous particle-scale mechanisms influence the bulk behaviour and flow of bulk materials. It is important that the relevant measurable input parameters for discrete element models be measured by laboratory equipment or determined by physical calibration experiments for rational results. This paper describes some of the bench-scale experiments that have been developed to calibrate the DEM simulations to reflect actual dynamic behaviour. Relevant parameters such as static and rolling coefficients of friction, coefficient of restitution and inter-particle cohesion forces from the presence of liquid bridges have been investigated to model the bulk behaviour of dry and moist granular materials. To validate the DEM models, the results have been checked against experimental slump tests and hopper discharge experiments to quantitatively compare the poured and drained angles of repose and solids mass flow rate. The calibration techniques presented have the capability to be scaled to model and fine tune DEM parameters of granular materials of varying length scales to obtain equivalent static and dynamic behaviour.