固定床内压降的CFD分析

摘要

采用CFD法分析填充单一粒径和不同粒径颗粒固定床内的压降。分别采用PFC3D和Fluent软件建立固定床模型和模拟计算压力场，床层内颗粒流动雷诺数Re_p介于1~2 200之间。将床层空隙率、压降等模拟结果分别与已发表文献中的半经验公式的计算结果进行了比较，发现当Re_p小于120左右时压降的模拟结果与半经验公式计算结果基本吻合；而当Re_p较高时，二者之间的偏差较大；大颗粒使床层内空隙率分布的峰位置向固定床中心移动，第1个峰的位置与固定床壁面之间的距离和颗粒的质量平均直径（d₄₃）值基本相同；采用d₄₃代替半经验公式中的粒径参数，得到的压降计算结果与模拟结果更加吻合。

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	王春雷
	王日杰
	杨晓霞
	乔胜超

关键词：压降固定床 CFD 颗粒直径空隙率

Abstract：

CFD method was used to study the pressure drop in the fixed bed packed with the particles of same and different diameter. PFC3D software was used for modeling of the fixed bed, and Fluent software was used to simulate the pressure field. The working range of the particle Reynolds numbers (Re_p) was from 1 to 2 200. Simulated results of the void fraction and pressure drop were compared with calculated results by the semi-empirical equation in published literature, which indicated that at low Re_p (Re_p<120), a good agreement was achieved between simulated and calculated results of the pressure drop. While at high Re_p, the difference between them was significant. Large particles made the peaks of void fraction profile moved toward the center of the fixed bed, and the distance from the first peak to the bed wall was almost same as the value of mass mean diameter (d₄₃). When the semi-empirical equation used d₄₃ instead of the original parameter, the corresponding calculated results of the pressure drop agreed better with CFD predicted resulted.

Keywords： pressure drop； fixed bed； CFD； particle diameter； void fraction

Received 2016-01-31;

Corresponding Authors: 杨晓霞,E-mail:xxy@tju.edu.cn。 Email: xxy@tju.edu.cn

About author: 王春雷(1987-),男,硕士研究生,现从事固定床反应器的数值模拟计算研究。

引用本文:

王春雷, 王日杰, 杨晓霞, 乔胜超.固定床内压降的CFD分析[J]. 化学工业与工程, 2017,34(6): 88-94

Wang Chunlei, Wang Rijie, Yang Xiaoxia, Qiao Shengchao.CFD Analysis to Pressure Drop in Fixed Bed[J]. Chemcial Industry and Engineering, 2017,34(6): 88-94

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