...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Mathematical Modelling >Comparison of non-cohesive resolved and coarse grain DEM models for gas flow through particle beds
【24h】

Comparison of non-cohesive resolved and coarse grain DEM models for gas flow through particle beds

机译：非粘性分辨和粗颗粒DEM模型通过颗粒床的气流比较

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The Discrete Element Method (DEM) is a widely used approach for modelling granular systems. Currently, the number of particles which can be tractably modelled using DEM is several orders of magnitude lower than the number of particles present in common large-scale industrial systems. Practical approaches to modelling such industrial system therefore usually involve modelling over a limited domain, or with larger particle diameters and a corresponding assumption of scale invariance. These assumption are, however, problematic in systems where granular material interacts with gas flow, as the dynamics of the system depends heavily on the number of particles. This has led to a number of suggested modifications for coupled gas-grain DEM to effectively increase the number of particles being simulated. One such approach is for each simulated particle to represent a cluster of smaller particles and to re-formulate DEM based on these clusters. This, known as a representative or 'coarse grain' method, potentially allows the number of virtual DEM particles to be approximately the same as the real number of particles at relatively low computational cost. We summarise the current approaches to coarse grain models in the literature, with emphasis on discussion of limitations and assumptions inherent in such approaches. The effectiveness of the method is investigated for gas flow through particle beds using resolved and coarse grain models with the same effective particle numbers. The pressure drop, as well as the pre and post fluidisation characteristics in the beds are measured and compared, and the relative saving in computational cost is weighed against the effectiveness of the coarse grain approach. In general, the method is found perform reasonably well, with a considerable saving of computational time, but to deviate from empirical predictions at large coarse grain ratios.
机译：离散元素方法（DEM）是一种广泛用于对粒度系统进行建模的方法。当前，可以使用DEM进行简单建模的粒子数量比常见的大型工业系统中存在的粒子数量低几个数量级。因此，对这种工业系统进行建模的实用方法通常涉及在有限域内进行建模，或者使用较大的粒径和相应的规模不变假设。但是，这些假设在颗粒物质与气流相互作用的系统中存在问题，因为系统的动力学很大程度上取决于粒子的数量。这导致对耦合气粒DEM进行许多建议的修改，以有效地增加要模拟的粒子的数量。一种这样的方法是让每个模拟粒子代表一个较小粒子的簇，并基于这些簇重新构造DEM。这被称为代表性或“粗粒”方法，可能以相对较低的计算成本允许虚拟DEM粒子的数量与实际粒子的数量近似相同。我们总结了文献中的粗粒模型的当前方法，重点讨论了此类方法固有的局限性和假设。使用具有相同有效颗粒数的分辨和粗颗粒模型，研究了该方法对通过颗粒床的气流的有效性。测量并比较床中的压降以及流化前后的特性，并权衡相对节省的计算成本和粗粒方法的有效性。通常，发现该方法表现良好，节省了大量的计算时间，但与大粗晶粒比下的经验预测有所不同。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号