化工学报 ›› 2020, Vol. 71 ›› Issue (S1): 57-67.doi: 10.11949/0438-1157.20191163

• 流体力学与传递现象 • 上一篇    下一篇

大空间重气泄漏下速度场、浓度场特性分析

张倩茹(),张旭(),叶蔚,职承强,黄奕翔,赵文萱,高军   

  1. 同济大学机械与能源工程学院,上海 201804
  • 收稿日期:2019-10-10 修回日期:2019-10-20 出版日期:2020-04-25 发布日期:2020-05-22
  • 通讯作者: 张旭 E-mail:zhangqianru@tongji.edu.cn;xuzhang@tongji.edu.cn
  • 作者简介:张倩茹(1990—),女,博士研究生,zhangqianru@tongji.edu.cn
  • 基金资助:
    国家自然科学基金项目(51878463);“十三五”国家重点研发计划专项(2018YFC0705300)

Analysis of velocity and concentration field characteristics of heavy gas leakage in large space

Qianru ZHANG(),Xu ZHANG(),Wei YE,Chengqiang ZHI,Yixiang HUANG,Wenxuan ZHAO,Jun GAO   

  1. School of Mechanical Engineering, Tongji University, Shanghai 201804, China
  • Received:2019-10-10 Revised:2019-10-20 Online:2020-04-25 Published:2020-05-22
  • Contact: Xu ZHANG E-mail:zhangqianru@tongji.edu.cn;xuzhang@tongji.edu.cn

摘要:

在实际的工业场景中,机器设备等障碍物的存在对污染物的扩散及分布有着很重要的影响。考虑了在有障碍物的大空间中,泄漏位置在障碍物两侧的场景。定义了污染源重力作用强度指标、无量纲浓度以及易燃易爆区域占比。用实验验证了计算流体力学(CFD)模型的准确性,进而用CFD计算了不同污染物释放速率时的速度场及浓度场。计算结果表明,随着污染物释放速率的增加,速度场的结构和浓度场的分布形式都发生变化。当无量纲数θinlet超过0.0288时,污染源附近会出现新的涡流,而无量纲浓度分布开始出现垂直分层的趋势。当污染源体积释放速率超过2.66667×10-5 m3/s时易燃易爆区域的大小变得显著,导致潜在的爆炸风险。

关键词: 流体力学, 重气, 实验验证, 速度场, 浓度场, 爆炸

Abstract:

In the real industrial plants, the equipments are often critical to the contaminant dispersion and distribution. The leakage position on both sides of the obstacle has been taken into consideration. Gravity intensity index, dimensionless concentration, and the proportion of flammable and explosive area have been defined. The accuracy of the computational fluid dynamics (CFD) model was verified by experiments, and the velocity field and concentration field of different pollutant release rates were calculated by CFD. The calculation results show that the structure of the velocity field and the distribution pattern of the concentration field change with the increase of the pollutant release rate. When the dimensionless number θinlet exceeds 0.0288, new eddy currents will appear near the pollution source, and the dimensionless concentration distribution begins to appear vertical stratification. When the contaminant volumetric release rate exceeds 2.66667×10-5 m3/s, the size of the flammable, explosive and explosive areas becomes significant, leading to potential explosion risks.

Key words: fluid mechanics, heavy gas, experimental validation, velocity field, concentration field, explosion

中图分类号: 

  • TQ 028.8

图1

Geometry Modeler中搭建的模型"

表1

模拟工况"

工况名称换气次数/h-1污染源位置/m

污染源释放强度/

(kg/(m3·s))

A13(0,4,0.5)1
A23(0,4,0.5)5
A33(0,4,0.5)10
A43(0,4,0.5)20
A53(0,4,0.5)50
B13(0,2,0.5)1
B23(0,2,0.5)5
B33(0,2,0.5)10
B43(0,2,0.5)20
B53(0,2,0.5)50

表2

各污染源释放强度对应的θinlet值"

污染源释放强度/(kg/(m3·s))θinlet
10.0106
50.0181
100.0228
200.0288
500.0390

图2

大空间实验台"

图3

障碍物及污染源示意图"

图4

测点位置"

图5

浓度场验证"

图6

无污染气体释放时Z=0.5 m平面的速度云图与流线"

图8

无污染气体释放时对称平面的速度云图与流线"

图7

无污染气体释放时Z=0.2 m平面的速度云图与流线"

图9

污染源在A(0,4 m,0.5 m)时Z=0.5 m平面的速度云图与流线"

图11

污染源在A(0,4 m,0.5 m)时对称平面的速度云图与流线"

图10

污染源在A(0,4 m,0.5 m)时Z =0.2 m平面的速度云图与流线"

图12

污染源在B(0,2 m,0.5 m)时Z =0.5 m平面的速度云图与流线"

图13

污染源在B(0,2 m,0.5 m)时Z =0.2 m平面的速度云图与流线"

图14

污染源在B(0,2 m,0.5 m)时对称平面的速度云图与流线"

图15

污染源在A(0,4 m,0.5 m)时对称平面的无量纲浓度云图"

图16

污染源在B(0,2 m,0.5 m)时对称平面的无量纲浓度云图"

图17

易燃易爆区域占比随污染气体体积释放流量的变化"

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