Three-dimensional CFD simulation of non-uniform diffusion characteristic of high-risk chlorine gas in large-scale dense scene

doi:10.11949/0438-1157.20250402

CIESC Journal ›› 2025, Vol. 76 ›› Issue (9): 4630-4643.DOI: 10.11949/0438-1157.20250402

• Special Column： Modeling and Simulation in Process Engineering • Previous Articles Next Articles

Three-dimensional CFD simulation of non-uniform diffusion characteristic of high-risk chlorine gas in large-scale dense scene

Sheng CHEN¹(), Zizheng LI¹^,², Chao MIAO³, Xuegang BAI¹, Fei LI⁴, Jiaxuan LIU¹, Tiantian LI¹^,², Shuang YANG¹, Rongrong LYU¹(), Jiangyun WANG²

^1.Technology Innovation Center of Risk Prevention and Control of Refining and Chemical Equipment, State Administration for Market Regulation, China Special Equipment Inspection and Research Institute, Beijing 100029, China
^2.China University of Petroleum-Beijing at Karamay, Karamay 834000, Xinjiang, China
^3.Research Institute of Natural Gas Technology, PetroChina Southwest Oil and Gasfield Company, Chengdu 610213, Sichuan, China
^4.State Key Laboratory of Mesoscience and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China

Received:2025-04-16 Revised:2025-06-11 Online:2025-10-23 Published:2025-09-25
Contact: Sheng CHEN, Rongrong LYU

大尺度密集场景高危氯气非均匀湍流扩散特性三维CFD模拟

陈昇¹(), 李子争¹^,², 苗超³, 白学刚¹, 李飞⁴, 刘家璇¹, 李天天¹^,², 杨爽¹, 吕蓉蓉¹(), 王江云²

^1.中国特种设备检测研究院，国家市场监督管理总局技术创新中心（炼油与化工装备风险防控），北京 100029
^2.中国石油大学（北京）克拉玛依校区，新疆克拉玛依 834000
^3.中国石油西南油气田分公司天然气研究院，四川成都 610213
^4.中国科学院过程工程研究所介科学与工程全国重点实验室，北京 100190

通讯作者: 陈昇,吕蓉蓉
作者简介:陈昇（1987—），男，正高级工程师，chensheng_csei@163.com
基金资助:
国家重点研发计划项目(2022YFC3004504);国家市场监管总局科技计划项目(2023MK203);国家自然科学基金项目(22208379);国家自然科学基金项目(U23A20374)

Abstract

Abstract:

Chlorine gas is highly toxic and tends to diffuse along the ground after leakage. The non-uniform turbulent vortex structures often lead to inaccurate diffusion predictions, causing improperly designed safety measures and accidents such as personnel poisoning. In order to guide on-site rapid risk assessment, safety sign layout, emergency response and rescue, it is necessary to accurately predict the law of non-uniform diffusion of chlorine in large-scale dense scenes. This paper adopts the single-phase Eulerian and species transport equations, establishing a simulation and prediction method for non-uniform turbulent dispersion of high-risk chlorine gas based on the energy minimization multi-scale (EMMS) turbulence model. Taking the liquid chlorine release experiment of Jack Rabbit as the object, the simulation accuracy was verified and the non-uniform diffusion characteristics of chlorine gas under varying wind speeds, wind directions and leakage rates were investigated. The results show that the proposed simulation method effectively predict the non-uniform diffusion of chlorine gas in large-scale and high-density scenarios, with errors within 8%. Increased wind speed accelerates the diffusion of chlorine gas in open areas but has limited effect on the concentration distribution in the container-intensive areas. The wind direction deviating from the symmetry axis of the building causes the narrow tube effect, causing the local concentration to rise instantaneously. After the leakage increases, the high concentration area expands to form a barrier effect, and the area with a chlorine volume fraction of more than 0.045 increases by 36.6 %.

Key words: chlorine, diffusion, Jack Rabbit, numerical simulation, computational fluid dynamics (CFD), obstacle

摘要：

氯气剧毒且泄漏后常沿地面扩散，非均匀湍流涡团结构常导致扩散预测不准、相关避险措施设置不合理、引发人员中毒等事故。为指导现场快速风险评估、安全标志布置、应急处置及救援，有必要精准预知大尺度密集场景下氯气非均匀扩散规律。采用单相欧拉和组分输运方程，建立了基于能量最小多尺度（EMMS）湍流模型的高危氯气非均匀湍流扩散模拟预测方法。以美国陆军Jack Rabbit液氯泄放实验为对象，验证模拟准确性并考察了不同风速、风向、泄漏量条件下氯气非均匀扩散特性。结果表明：提出的模拟方法能较好地预测大尺度密集场景氯气非均匀扩散，误差在8%以内；风速增大会加速开阔区域氯气扩散，但对集装箱密集区浓度分布影响有限；风向偏离建筑对称轴引发“狭管效应”，会使局部浓度瞬间上升；泄漏量增大后，高浓度区域扩大形成“屏障效应”，氯气体积分数为0.045以上的面积占比增加36.6%。

关键词: 氯气, 扩散, Jack Rabbit, 数值模拟, 计算流体力学, 障碍物

CLC Number:

X 937

Sheng CHEN, Zizheng LI, Chao MIAO, Xuegang BAI, Fei LI, Jiaxuan LIU, Tiantian LI, Shuang YANG, Rongrong LYU, Jiangyun WANG. Three-dimensional CFD simulation of non-uniform diffusion characteristic of high-risk chlorine gas in large-scale dense scene[J]. CIESC Journal, 2025, 76(9): 4630-4643.

陈昇, 李子争, 苗超, 白学刚, 李飞, 刘家璇, 李天天, 杨爽, 吕蓉蓉, 王江云. 大尺度密集场景高危氯气非均匀湍流扩散特性三维CFD模拟[J]. 化工学报, 2025, 76(9): 4630-4643.

Figures/Tables 18

Fig.1 Comparison of Jack Rabbit’s actual experimental scene and CFD simulation scene

Fig.2 Jack Rabbit test site space layout diagram

Fig.3 Grid division diagram

Fig.4 Distribution characteristics of chlorine concentration in flow field under various grid sizes

Table 1 Test conditions

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
Trial-1	2.47	95	16	4.97	0.1971
Trial-2	4.06	85	25	8.98	0.2280
Trial-6	2.88	90	25	9.2	0.2336

Table 2 Simulation settings

类别	边界类型	参数	Trial-1	Trial-2	Trial-6
环境风入口	velocity-inlet	速度/(m/s)	2.47	4.06	2.88
		风向/(°)	95	85	90
		温度/℃	26.7	26.7	26.7
		各组分浓度/%	air：100	air：100	air：100
泄漏入口	velocity-inlet	速度/(m/s)	0.1971	0.2280	0.2236
		各组分浓度/%	Cl₂： 100	Cl₂： 100	Cl₂： 100
		温度/℃	26.7	26.7	26.7
流体域侧面1、2	symmetry	温度/℃	26.7	26.7	26.7
地面	wall	粗糙度	0.5	0.5	0.5
地面	wall	温度/℃	26.7	26.7	26.7
集装箱集群	wall	粗糙度	0.5	0.5	0.5
集装箱集群	wall	温度/℃	26.7	26.7	26.7
环境风出口	outflow	温度/℃	26.7	26.7	26.7

Fig.5 The corresponding position of each boundary and the position of monitoring points

Fig.6 The distribution of chlorine concentration under different diffusion models

Fig.7 Trial-2 simulation results and report data

Fig.8 Trial-6 simulation results and report data

Table 3 Simulation settings under different parameters

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

Fig.9 Time evolution of concentration distributions for chlorine gas in XZ section at different wind speeds

Fig.10 The distribution of chlorine diffusion concentration in XY section at different wind speeds and different times

Fig.11 The variation of chlorine concentration with time at different wind speeds and different monitoring points

Fig.12 Diffusion velocity streamline and concentration distribution diagram of chlorine under different wind directions

Fig.13 Time evolution of chlorine concentration at different wind directions and monitoring points

Fig.14 Concentration distribution characteristics of chlorine gas under different leakage mass

Fig.15 Time evolution of chlorine concentration for different leakage mass at various positions

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Three-dimensional CFD simulation of non-uniform diffusion characteristic of high-risk chlorine gas in large-scale dense scene

大尺度密集场景高危氯气非均匀湍流扩散特性三维CFD模拟

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Figures/Tables 18

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编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

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编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3

编号	风速/(m/s)	风向/(°)	泄漏时间/s	泄漏量/t	泄漏速度/(m/s)
1	2.5	90	20	5	3
2	4.0	90	20	5	3
3	3.0	70	20	5	3
4	3.0	90	20	5	3
5	2.5	90	20	5	3
6	2.5	90	20	10	3