宋晓皎¹， 王 帅²

（1. 山西能源学院能源与动力工程系， 山西晋中 030600；2. 哈尔滨工业大学能源科学与工程学院， 黑龙江哈尔滨 150001）

DOI:10.13732/j.issn.1008-5548.2021.04.015

收稿日期： 2020-12-23， 修回日期：2021-04-20，在线出版时间：2021-06-03 14:07。

基金项目：国家自然科学基金项目，编号：51606053。

第一作者简介：宋晓皎(1992—)，女，硕士研究生，研究方向为多组分颗粒相间作用机理。E-mail: 2812246135@qq.com。

摘要：为了对鼓泡流化床内双组分颗粒混合过程进行更精准的计算流体力学(CFD)数值模拟，结合颗粒动力学理论和欧拉多流体模型，建立以气泡为介尺度的双组分曳力模型，在三维鼓泡流化床反应器中模拟了双组分颗粒的分离和混合过程，并通过实验数据验证该模型的准确性，分析外界操作条件和颗粒物性参数对双组分颗粒的分离和混合过程的影响。结果表明:固相颗粒直径的减小、气体入口表观速度的增大以及床层温度的升高都将会加大两相间曳力的非均质性，固相颗粒混合程度逐渐加大;随着颗粒直径和入口气体表观速度的减小，两相颗粒分离程度加大，混合指数随之减小;颗粒物性和外界操作条件的合理匹配有利于双组分颗粒的分离。

关键词：介尺度曳力模型；双组分颗粒；混合；鼓泡流化床；CFD数值模拟

Abstract：In order to conduct more accurate computational fluid dynamics( CFD) numerical simulation of two-component particle mixing in a bubbling fluidized bed,a two-component drag force model with bubbles as meso-scale was established by combining particle dynamics theory and Euler multi-fluid model. The separation and mixing process of two-component particles was simulated in a three-dimensional bubbling fluidized bed reactor,and the accuracy of the model was verified by experimental data. The effects of external operating conditions and particle properties on the separation and mixing process of two-component particles were analyzed. The results show that the decrease of particle diameter,the increase of apparent velocity of gas inlet and the increase of bed temperature increase the heterogeneity of drag force between the two phases,and the mixing degree of solid particles increases gradually. With the decrease of particle diameter and inlet gas apparent velocity,the separation degree of two-phase particles increases and the mixing index decreases. Reasonable matching of particle properties and external operating conditions is beneficial to the separation of two-component particles.

Keywords：meso-scale drag force model; two-component particle; mixed; bubbling fluidized bed; computational fluid dynamics numerical simulation

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