PENG Deqi1， WANG Yiran1， HOU Jiaxin1， YU Tianlan2，WU Shuying1， WANG Zhiping3
(1. School of Mechanical Engineering, Xiangtan University, Xiangtan 411105, China; 2. School of Mechanical Engineering,Hunan University of Technology, Zhuzhou 412007, China; 3. Xiangtan Boiler Co.,Ltd.,Xiangtan 411202, China)
Abstract: In order to explain the liquid-solid two-phase flow mechanism of ellipsoidal particles in the tubular heat exchanger, based on the CFD-DEM coupling method, the effect of the length-diameter ratio β and the particle volume fraction α of the ellipsoid particles on the particle distribution and motion characteristics were simulated and analyzed in the vertical upward heat transfer tube. The relative velocities of liquid-solid two phases after stable motion were analyzed, and the slip coefficient was used to quantify the evolution of the particle following. The results show that the radial distribution of particles on the cross section is similar at any time during the dynamic stability period, and when the particles move from bottom to top with the fluid, they slowly approach the wall in the radial direction of the tube, and the relative particle volume fraction in the center of the tube become lower. The slip coefficient of ellipsoidal particles is greater than that of spherical particles, when β is 1.5, the slip coefficient of ellipsoidal particles reaches the greatest.
Keywords: liquid-solid two-phase flow; ellipsoidal particles; distribution characteristics; movement characteristics; CFD-DEM coupling method; slip coefficient
中图分类号：O359
文献标志码：A
文章编号：1008-5548(2021)05-0094-11
DOI:10.13732/j.issn.1008-5548.2021.05.012
收稿日期： 2021-02-28，修回日期：2021-04-24，在线出版时间：2021-08-17 10:54。
基金项目：湖南省自然科学基金项目，编号：2018JJ4054；湘潭市科技局计划项目，编号：GX-YB20201011。
第一作者简介：彭德其(1972—)，男，教授，博士，研究方向为过程强化与节能环保。E-mail： pengshuaike@163.com。
