在拉力模型的升高效应中对集群行为的CFD-DEM评估
Juan Ramírez1, Martijn de Munck1, Zhitao Liu1
1Multiphase Reactors Group, Department of Chemical Engineering & Chemistry, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands.
Industrial & engineering chemistry research
|November 29, 2023
概括
本研究研究了使用计算流体动力学和离散元素方法在起伏反应堆中的粒子聚类. 菲利斯和唐等人. 拖力相关性在快速流化模式中最好预测集群行为.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 流体动力学 流体动力学
- 颗粒技术 颗粒技术
背景情况:
- 升级反应堆对于催化过程至关重要,但由于催化剂失效而受到影响.
- 由粒子聚类引起的异质流结构会损害气体与固体的接触.
- 粒子聚类是由流体-粒子阻力和粒子-粒子碰撞之间的相互作用引起的.
研究的目的:
- 为了评估在起伏反应堆中粒子聚类的不同阻力相关性的预测准确性.
- 为了比较模拟结果与实验数据在一个伪-2D riser.
- 为了确定可靠的相关性,模拟气体-固体流动力学.
主要方法:
- 采用了混合计算流体动力学-离散元件方法 (CFD-DEM) 浸入边界模型.
- 为了模拟,利用了五种不同的拖力相关性.
- 经过验证的模型预测与实验数据的伪2D riser运行在快速流化制度的实验数据.
- 使用核心唤醒方法与恒定值检测到的粒子集群.
主要成果:
- 两种拖力相关性证明了对全球变量 (固体体积分,质量流) 和集群特征 (分布,大小,数量) 的良好预测.
- 所有测试的相关性都在预测气动运输模式的开始时表现出偏差.
- 菲利斯和唐等人. 相关性显示了与实验数据最接近的时间平均数量和快速流化中的集群行为.
结论:
- 菲利斯和唐等人. 推推拉力相关性用于准确建模起反应堆内的快速流化模式中的粒子聚类.
- 精确的阻力模拟对于预测气体-固体流动行为和优化 riser反应堆性能至关重要.
- 可能需要进一步的研究来改善过渡到气动运输制度时的预测.
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