...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Powder Technology: An International Journal on the Science and Technology of Wet and Dry Particulate Systems >CPFD study of a full-loop three-dimensional pilot-scale circulating fluidized bed based on EMMS drag model
【24h】

CPFD study of a full-loop three-dimensional pilot-scale circulating fluidized bed based on EMMS drag model

机译：基于EMMS拖曳模型的全环三维先导尺度循环流化床的CPFD研究

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

For the purpose of process optimization and scale-up, coupling energy-minimization multi-scale (EMMS) drag model with computational particle fluid dynamics (CPFD) is a good option for large scale three dimensional full-loop circulating fluidized bed (CFB) simulation. In this study, such integration is applied for a complex CFB with six cyclones, based on Barracuda platform, to investigate the gas-solids flow dynamic characteristics in scaled-up system, especially in the dense flow region, and to characterize different fluidization regimes. The simulation results are compared with those obtained from Wen-Yu model, in terms of axial pressure distribution, solid volume fraction, particle recirculation, etc., and are evaluated against available measurement data. The result demonstrates that EMMS drag model can predict the axial pressure distribution well, especially in the dense region, which gives an S-shape solid volume fraction in the axial direction and two-core-annulus structures ('M' shape) in the radial direction. Meanwhile, EMMS drag model provides smaller drag force between the gas phase and the solids that the particle recirculation fluxes inside and outside the riser is relatively smaller. With the increase of superficial gas velocity, three different fluidization regimes, including multiple bubble regime, exploding bubble regime and turbulent fluidization regime, are identified based on EMMS drag model. The results show that the dense region is clear at the multiple and exploding bubble regimes; while the particle volume fraction and mass flow rate in the riser top are larger than those in the middle at the turbulent fluidization regime, which gives a guidance that the riser height is limited that particles do not have enough space to distribute. (C) 2017 Elsevier B.V. All rights reserved.
机译：出于过程优化和扩展的目的，具有计算粒子流体动力学（CPFD）的耦合能量 - 最小化多尺度（EMM）拖曳模型是大规模三维全环循环流化床（CFB）仿真的良好选择。在这项研究中，这种积分应用于基于Barracuda平台的六个旋风分离器的复杂CFB，以研究缩放系统中的气体固体流动动态特性，特别是在致密流动区域中，并表征不同的流化制度。将模拟结果与来自文宇模型获得的仿真结果相比，在轴向压力分布，固体体积分数，颗粒再循环等方面，并评估可用的测量数据。结果表明，EMM拖曳模型可以预测轴向压力分布孔，特别是在致密区域中，其在轴向方向和两个芯 - 环形结构（径向中的两个芯环结构（'m'形）中提供S形固体体积分数方向。同时，EMM拖曳模型在气相和提升器内部和外部的固体之间提供较小的拖曳力。随着浅表气体速度的增加，基于EMM拖动模型鉴定了三种不同的流化制度，包括多个泡沫制度，爆炸泡沫制度和湍流流化制度。结果表明，致密区域在多个和爆炸泡沫制度下透明;虽然提升管顶部的粒子体积分数和质量流速大于湍流流化制度的中间中的颗粒，其给出了提升管高度限制的引导术，颗粒没有足够的空间来分配。 （c）2017 Elsevier B.v.保留所有权利。

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