Simulation of flow-reaction process in fluidized bed gasifier considering particle rotational motion

doi:10.11949/j.issn.0438-1157.20151663

Abstract

Abstract:

Abandoning the pure smooth assumption of particles in classical kinetic theory of granular flow, this work established a kinetic theory model for rough granular and provided relevant constitutive correlations with approximate solutions by considering both opposite and tangential components force of the rough granular. Combined with the gasification model of coal powders, the flow-reaction process of coal powders was simulated in a bubbling fluidized bed and the time-average velocity and particle concentration distributions with rough granular were obtained in the bed. The simulated fluctuating energy and heterogeneity of rough granular in the fluidized bed increased compared with the simulated results of the smooth particles. The concentration of gas components obtained in the simulation agreed well with the experimental data in the literature.

Key words: fluidized bed, kinetic modeling, particle collision, particle rotation, numerical simulation

摘要：

摒弃传统颗粒动力学模型中颗粒绝对光滑的假设,以粗糙颗粒为研究对象,同时考虑颗粒碰撞过程中的对心和切向分力建立了粗糙颗粒动力学模型,采用近似求解给出了相关本构关系式。结合粉煤气化反应模型模拟研究了鼓泡流化床内粉煤颗粒的流动-反应过程,获得了床内粗糙颗粒时均速度和浓度的径向分布。与光滑颗粒的计算结果相比,粗糙颗粒的脉动能量增大,床内不均匀特性进一步增强。同时得到的各气体组分的浓度分布与他人的实验结果相吻合。

关键词: 流化床, 动力学模型, 颗粒碰撞, 颗粒旋转, 数值模拟

CLC Number:

TQ53

WANG Zhiyu, HAO Zhenhua, DONG Libo, LI Junguo, LU Huilin. Simulation of flow-reaction process in fluidized bed gasifier considering particle rotational motion[J]. CIESC Journal, 2016, 67(5): 1725-1731.

王志宇, 郝振华, 董立波, 李俊国, 陆慧林. 考虑颗粒旋转的流化床流动和气化反应模拟[J]. 化工学报, 2016, 67(5): 1725-1731.

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