2023年 01期

摘要(Abstract)：

为了解决颗粒分离的解释机制众多、尚未完全统一的问题，进一步揭示剪切分离更深刻的机制，采用开源软件LIGGGHTS构建三维离散元剪切模型，分析大颗粒周围的空间排列结构，探讨摩擦力、壁面、尺寸差异、惯性等因素对空间结构变化的影响。结果表明：大颗粒能够向上爬升是在2种机制共同作用下进行的；小颗粒群在竖直方向存在速度梯度，层与层的动量传递发生损耗；大颗粒的尺寸效应体现在对前上方小颗粒动量传递模式的改变，由此产生空隙；大颗粒前期靠挤压上升，空隙的产生是大颗粒上升的充分条件；大颗粒后期在后传递颗粒的旋转传动下，沿着小颗粒表面上升。

关键词(KeyWords)： 致密颗粒流;颗粒分离;离散元法;剪切力

基金项目(Foundation): 国家自然科学基金项目(51776043)

作者(Author): 黄仕昭,郑麟,李玉秀,陈颖

DOI: 10.13349/j.cnki.jdxbn.20221104.001

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