Study on mechanism and law of liquid overheating and explosive boiling caused by leakage

doi:10.11949/j.issn.0438-1157.20190617

Abstract

Abstract:

To explore the mechanism and law of liquid superheating and boiling caused by tank leakage, a small device was established to study the bubble evolution, pressure and medium superheat response during the bumping process. Upon the typical features of medium superheat degree, overheat time was further introduced to characterize the delay degree of boiling. The results show that a large number of bubbles were generated and grew rapidly in the medium after the vessel rupture. Bubble-growth process could be divided into a relatively stable stage and an accelerated stage, and the obvious pressure recovery was attributed to the accelerated growth of bubbles. According to the response of temperature sensors in the medium, the boiling occurred and spread from top to bottom and from the inner wall to the inside of the medium. And the medium underwent a cycle of supercoiling—saturation—superheat—saturation—supercooling during boiling. In addition, it was found that the increase of initial pressure and the decrease of initial liquid level could both improve the maximum superheat degree of medium, especially a maximum superheat of 9. 4℃ with the initial liquid level of 50%. What’s more, the ascent of the initial pressure or the initial liquid level also hold a significant lower overheat time. And the rise of the initial liquid level would contribute to a more serious rebound phenomena of pressure. On the basis of the overheat time obtained by experiments, the mathematical model of the overheat time was also verified. The results showed that the calculation of the mathematical model was basically consistent with the experimental data.

Key words: explosive boiling, vaporization, two-phase flow, superheat degree, overheat time, model

摘要：

为探究储罐泄漏引发液体过热爆沸的机理及规律，实验建立了小型装置，对爆沸过程中的气泡演化、压力及介质过热度响应进行研究。根据介质过热度的变化特征，提出表征沸腾延时程度的参数——过热时间，并建立相应描述过热时间的数学模型。实验结果表明，容器破裂后，大量气泡于介质内部产生并迅速成长，其成长可分为相对稳定阶段与加速成长阶段，而后引起明显的压力反弹。整个沸腾自上而下、自内壁向介质内部进行，且介质经历过冷—饱和—过热—饱和—过冷的循环过程。此外，实验发现初始压力的升高或初始液位的降低，都会使介质达到的最大过热度提高，尤其是50%初始液位时其介质最大过热度高达9.4℃。而随着初始压力或初始液位的升高，过热时间呈明显降低趋势，且初始液位升高时还会引起更明显的压力反弹。基于实验数据，对过热时间数学模型进行验证，结果表明数学模型计算结果和实验数据基本吻合。

关键词: 爆沸, 气化, 两相流, 过热度, 过热时间, 模型

CLC Number:

X 933

Shicheng SHI, Supan WANG, Xuhai PAN, Yuheng MA, Juncheng JIANG. Study on mechanism and law of liquid overheating and explosive boiling caused by leakage[J]. CIESC Journal, 2019, 70(10): 4089-4098.

时事成, 王苏盼, 潘旭海, 马煜衡, 蒋军成. 泄漏引发液体过热爆沸机理及规律研究[J]. 化工学报, 2019, 70(10): 4089-4098.

Figures/Tables 11

Fig.1 Experiment setup of explosion boiling

Fig.2 Pressure response and partial magnification diagram at initial pressure of 2.7 bar and initial liquid level of 70%

Fig.3 Evolution of bubbles and two-phase flow in upper liquid phase after pressure relief

Fig.4 Liquid surface height and rising rate of liquid surface versus time under different initial pressures

Fig.5 Medium temperature curves after pressure relief at initial pressure of 3.7 bar and initial liquid level of 70%

Fig.6 Temperature-pressure diagram of medium under various initial pressures (at initial liquid level of 70%)

Table 1 Summary of maximum superheat degree that medium can achieve during boiling under different conditions

实验序号	初始压力/bar	初始液位/%	平均最大过热度/℃	标准偏差
1	1.7	70	6.8	0.25
2	2.7	70	7.3	0.15
3	3.7	70	8.2	0.25
4	4.7	70	8.9	0.21
5	2.7	50	9.4	0.32
6	2.7	60	7.9	0.15
7	2.7	80	3.0	0.21

Fig.7 Pressure response after pressure relief at initial pressure of 3.7 bar and initial liquid level of 70%

Fig.8 Effects of initial pressure on decompression rate, pressure boost ratio and overheat time

Fig.9 Effects of initial liquid level on decompression rate, pressure boost ratio and overheat time

Table 2 Comparison of theoretical and experimental results of overheat time

序号	初始压力/bar	初始液位/%	初始气相体积/L	理论过热时间 t/ms	实验测量平均过热时间 $t ˉ$ /ms	相对误差/%	平均误差/%
1	1.7	70	5.2	54.4	49.6	9.7	9.2
2	2.7	70	5.2	49.9	46.3	7.8
3	3.7	70	5.2	20.5	23.3	12.0
4	4.7	70	5.2	12.3	13.6	9.6
5	2.7	50	8.6	74.2	68.3	8.6
6	2.7	60	6.9	60.6	55.7	8.8
7	2.7	80	3.5	34.2	31.7	7.9

Table 2 Comparison of theoretical and experimental results of overheat time

序号	初始压力/bar	初始液位/%	初始气相体积/L	理论过热时间 t/ms	实验测量平均过热时间 $t ˉ$ /ms	相对误差/%	平均误差/%
1	1.7	70	5.2	54.4	49.6	9.7	9.2
2	2.7	70	5.2	49.9	46.3	7.8
3	3.7	70	5.2	20.5	23.3	12.0
4	4.7	70	5.2	12.3	13.6	9.6
5	2.7	50	8.6	74.2	68.3	8.6
6	2.7	60	6.9	60.6	55.7	8.8
7	2.7	80	3.5	34.2	31.7	7.9

References 30

1	AbbasiT, AbbasiS A. The boiling liquid expanding vapour explosion (BLEVE): mechanism, consequence assessment, management[J]. Journal of Hazardous Materials, 2007, 141(3): 489-519.
2	王晓东, 田勇, 彭晓峰, 等. 沸腾核心内部结构及其演化特性[J]. 化工学报, 2005, 56(5): 812-815.
	WangX D, TianY, PengX F, et al. Inner structure and evolution of boiling nucleus[J]. Journal of Chemical Industry and Engineering(China), 2005, 56(5): 812-815.
3	HemmatianB, PlanasE, CasalJ. Fire as a primary event of accident domino sequences: the case of BLEVE[J]. Reliability Engineering & System Safety, 2015, 139: 141-148.
4	TauseefS M, AbbasiT, AbbasiS A. Risks of fire and explosion associated with the increasing use of liquefied petroleum gas[J]. Journal of Failure Analysis and Prevention, 2010, 10(4): 322-333.
5	陈思凝. 沸腾液体膨胀蒸气爆炸(BLEVE)动力演化机理的小尺寸模拟试验研究[D]. 合肥: 中国科学技术大学, 2007.
	ChenS N. Small scale experimental study on boiling liquid expanding vapor explosions mechanism[D]. Hefei: University of Science and Technology of China, 2007.
6	石剑云. 液化气体的热分层及爆沸机理研究[D]. 大连: 大连理工大学, 2015.
	ShiJ Y. Research on the mechanisms of thermal stratification and explosive boiling of liquefied gas[D]. Dalian: Dalian University of Technology, 2015.
7	BartákJ. A study of the rapid depressurization of hot water and the dynamics of vapor bubble generation in superheated water[J]. International Journal of Multiphase Flow, 1990, 16(5): 789-798.
8	李清, 张德平, 孙瑞艳, 等. 固态CO₂-BLEVE过程中的压力与温度变化试验研究[J]. 安全与环境学报, 2018, 18(6): 103-109.
	LiQ, ZhangD P, SunR Y, et al. Experimental approach to the pressure and temperature changes in the solid CO₂-BLEVE process[J]. Journal of Safety and Environment, 2018, 18(6): 103-109.
9	REIDR C. Possible mechanism for pressurized-liquid tank explosions or BLEVE’s[J]. Science, 1979, 203(4386): 1263-1265.
10	BjerketvedtD, EgebergK, KeW, et al. Boiling liquid expanding vapour explosion in CO₂ small scale experiments[J]. Energy Procedia, 2011, 4(1): 2285-2292.
11	BartakJ. A study of the rapid depressurization of hot water and the dynamics of vapour bubble generation in superheated water[J]. International Journal of Multiphase Flow, 1990, 16(5): 789-798.
12	ZhangQ, BiQ, WuJ, et al. Experimental investigation on the rapid evaporation of high-pressure R113 liquid due to sudden depressurization[J]. International Journal of Heat and Mass Transfer, 2013, 61: 646-653.
13	McDevittC A, ChanC K, StewardF R, et al. Initiation step of boiling liquid expanding vapor explosions[J]. Journal of Hazardous Materials, 1990, 25(1): 169-180.
14	NutterD W, O'nealD L. Modeling the transient outlet pressure and mass flow during flashing of HCFC-22 in a small nonadiabatic vessel[J]. Mathematical & Computer Modelling An International Journal, 1999, 29(8): 105-116.
15	SumathipalaK, VenartJ E S, StewardF R. Two-phase swelling and entrainment during pressure relief valve discharges[J]. Journal of Hazardous Materials, 1990, 25(1): 219-236.
16	StawczykJ. Experimental evaluation of LPG tank explosion hazards[J]. Journal of Hazardous Materials, 2003, 96(2/3): 189-200.
17	ChenS N, SunJ H, ChuG Q. Small scale experiments on boiling liquid expanding vapor explosions: vessel over-pressure[J]. Journal of Loss Prevention in the Process Industries, 2007, 20(1): 45-51.
18	ChenS N, SunJ, WeiW. Boiling liquid expanding vapor explosion: experimental research in the evolution of the two-phase flow and over-pressure[J]. Journal of Hazardous Materials, 2008, 156(1): 530-537.
19	BirkA M, PoirierD, DavisonC. On the response of 500 gal propane tanks to a 25% engulfing fire[J]. Journal of Loss Prevention in the Process Industries, 2006, 19(6): 527-541.
20	BirkA M, DavisonC, CunninghamM. Blast overpressures from medium scale BLEVE tests[J]. Journal of Loss Prevention in the Process Industries, 2007, 20(3): 194-206.
21	ShiJ Y, RenJ J, LiuP, et al. Experimental research on the effects of fluid and heater on thermal stratification of liquefied gas[J]. Experimental Thermal and Fluid Science, 2013, 50: 29-36.
22	任婧杰. 热环境下液化气体储罐热质耦合响应机制研究[D]. 大连: 大连理工大学, 2014.
	RenJ J. Research on heat-mass coupling response mechanism of liquefied gas tanks under thermal environments[D]. Dalian: Dalian University of Technology, 2015.
23	RenJ J, ShiJ Y, LiuP, et al. Simulation on thermal stratification and de-stratification in liquefied gas tanks[J]. International Journal of Hydrogen Energy, 2013, 38(10): 4017-4023.
24	周轶. 驱油过程中二氧化碳BLEVE机理及破坏效应研究[D]. 北京: 北京理工大学, 2015.
	ZhouY. Study on the mechanism and damage effect of CO₂ boiling liquid expanding vapor explosion in CO₂ flooding[D]. Beijing: Beijing Institute of Technology, 2015.
25	LiM Z, LiuZ Y, ZhouY, et al. A small-scale experimental study on the initial burst and the heterogeneous evolution process before CO₂ BLEVE[J]. Journal of Hazardous Materials, 2017, 342: 634-642.
26	TosseS, VaagsaetherK, BjerketvedtD. An experimental investigation of rapid boiling of CO₂[J]. Shock Waves, 2014, 25(3): 277-282.
27	PetersonR J, GrewalS S, Ei-WakilM M. Investigations of liquid flashing and evaporation due to sudden depressurization[J]. International Journal of Heat & Mass Transfer, 1984, 27(2): 301-310.
28	王庆慧, 邹伟, 荣皓月. BLEVE超压模型与试验对比分析[J]. 安全与环境学报, 2016, 16(4): 116-120.
	WangQ H, ZouW, RongH Y. BLEVE overpressure model and its experimental comparative analysis[J]. Journal of Safety and Environment, 2016, 16(4): 116-120.
29	王庆慧. 压力容器蒸汽爆炸临界条件分析及后果仿真[D]. 大庆: 东北石油大学, 2011.
	WangQ H. On vapor explosion critical condition analysis and simulation of the pressure vessel[D]. Daqing: Northeast Petroleum University, 2011.
30	王庆慧. 实验测定过热水发生BLEVE现象的反应时间[J]. 科学技术与工程, 2010, 10(26):6477-6480.
	WangQ H. The experimental determination reaction time of BLEVE phenomenon produced by superheated water[J]. Science Technology and Engineering, 2010, 10(26): 6477-6480.

[1]	Shaohua ZHOU, Feilong ZHAN, Guoliang DING, Hao ZHANG, Yanpo SHAO, Yantao LIU, Zheming GAO. Experimental study of flow noise in short tube throttle valve and noise reduction measures [J]. CIESC Journal, 2023, 74(S1): 113-121.
[2]	Jiahao SONG, Wen WANG. Study on coupling operation characteristics of Stirling engine and high temperature heat pipe [J]. CIESC Journal, 2023, 74(S1): 287-294.
[3]	Mengya LIAN, Yingying TAN, Lin WANG, Feng CHEN, Yifei CAO. Heating performance of air preheated integrated ground water heat pump air-conditioning system [J]. CIESC Journal, 2023, 74(S1): 311-319.
[4]	Zhenghao JIN, Lijie FENG, Shuhong LI. Energy and exergy analysis of a solution cross-type absorption-resorption heat pump using NH₃/H₂O as working fluid [J]. CIESC Journal, 2023, 74(S1): 53-63.
[5]	Mingkun XIAO, Guang YANG, Yonghua HUANG, Jingyi WU. Numerical study on bubble dynamics of liquid oxygen at a submerged orifice [J]. CIESC Journal, 2023, 74(S1): 87-95.
[6]	Kaijie WEN, Li GUO, Zhaojie XIA, Jianhua CHEN. A rapid simulation method of gas-solid flow by coupling CFD and deep learning [J]. CIESC Journal, 2023, 74(9): 3775-3785.
[7]	Yubing WANG, Jie LI, Hongbo ZHAN, Guangya ZHU, Dalin ZHANG. Experimental study on flow boiling heat transfer of R134a in mini channel with diamond pin fin array [J]. CIESC Journal, 2023, 74(9): 3797-3806.
[8]	Ke LI, Jian WEN, Biping XIN. Study on influence mechanism of vacuum multi-layer insulation coupled with vapor-cooled shield on self-pressurization process of liquid hydrogen storage tank [J]. CIESC Journal, 2023, 74(9): 3786-3796.
[9]	Song HE, Qiaomai LIU, Guangshuo XIE, Simin WANG, Juan XIAO. Two-phase flow simulation and surrogate-assisted optimization of gas film drag reduction in high-concentration coal-water slurry pipeline [J]. CIESC Journal, 2023, 74(9): 3766-3774.
[10]	Hao WANG, Zhenlei WANG. Model simplification strategy of cracking furnace coking based on adaptive spectroscopy method [J]. CIESC Journal, 2023, 74(9): 3855-3864.
[11]	Xudong YU, Qi LI, Niancu CHEN, Li DU, Siying REN, Ying ZENG. Phase equilibria and calculation of aqueous ternary system KCl + CaCl₂ + H₂O at 298.2, 323.2, and 348.2 K [J]. CIESC Journal, 2023, 74(8): 3256-3265.
[12]	Chengying ZHU, Zhenlei WANG. Operation optimization of ethylene cracking furnace based on improved deep reinforcement learning algorithm [J]. CIESC Journal, 2023, 74(8): 3429-3437.
[13]	Linqi YAN, Zhenlei WANG. Multi-step predictive soft sensor modeling based on STA-BiLSTM-LightGBM combined model [J]. CIESC Journal, 2023, 74(8): 3407-3418.
[14]	Guoze CHEN, Dong WEI, Qian GUO, Zhiping XIANG. Optimal power point optimization method for aluminum-air batteries under load tracking condition [J]. CIESC Journal, 2023, 74(8): 3533-3542.
[15]	Jintong LI, Shun QIU, Wenshou SUN. Oxalic acid and UV enhanced arsenic leaching from coal in flue gas desulfurization by coal slurry [J]. CIESC Journal, 2023, 74(8): 3522-3532.