Grid independence behaviour of fluidized bed reactor simulations using the Two Fluid Model: Detailed parametric study
Grid independence behaviour of fluidized bed reactor simulations using the Two Fluid Model: Detailed parametric study
复制标题
DOI：
10.1016/j.powtec.2015.11.011
复制
发表时间：
2016-02
影响因子：
5.2
通讯作者：
Schalk Cloete;S. T. Johansen;S. Amini
中科院分区：
文献类型：
--
作者：
Schalk Cloete;S. T. Johansen;S. Amini
这个简短的交流建立在以前的工作上的网格独立行为的反应鼓泡流化床模拟的两个流体模型。关于流体动力学网格独立性行为（解决相分离的数值精度），粒子弛豫时间被确认为与实现充分的网格独立性行为的单元尺寸成正比。这种关系保持在不同的颗粒尺寸，颗粒密度，气体密度，气体粘度和阻力定律，但比例的斜率改变颗粒弛豫时间0.4以上。对于反应性网格独立行为（反应器性能解决的数值精度），颗粒弛豫时间和充分独立于网格的单元格尺寸之间的关系更加复杂，不仅取决于相分离的分辨率，而且取决于实施的动力学速率和乳液相的渗透性。提出了简单实用的经验法则，用于估算流体动力学和反应模拟中充分独立于网格的单元尺寸。对于大多数实际的目的，更简单和更准确的流体动力学网格独立的细胞大小的相关性可以安全地用于运行足够准确的鼓泡流化床反应器模拟。
This short communication builds on previous work on the grid independence behaviour of the Two Fluid Model in reactive bubbling fluidized bed simulations. Regarding hydrodynamic grid independence behaviour (the numerical accuracy with which phase segregation was resolved), the particle relaxation time was confirmed as being directly proportional to the cell size achieving sufficiently grid independent behaviour. This relationship held over different particle sizes, particle densities, gas densities, gas viscosities and drag laws, but the slope of the proportionality changed for particle relaxation times above 0.4. For reactive grid independence behaviour (the numerical accuracy with which reactor performance was resolved), the relationship between the particle relaxation time and the sufficiently grid independent cell size was more complex, depending not only on the resolution of phase segregation, but also on the kinetic rate implemented and on the permeability of the emulsion phase. Simple and practical rules of thumb were proposed for estimating the sufficiently grid independent cell size for hydrodynamic and reactive simulations. For most practical purposes, the simpler and more accurate hydrodynamic grid independent cell size correlation can safely be used to run sufficiently accurate bubbling fluidized bed reactor simulations.