Effect of initial buoyancy ratio on stratification instability of multi-component liquids

doi:10.16085/j.issn.1000-6613.2019-0173

Abstract

Abstract:

The experimental study method was used to construct a multi-component liquid stratification system in a visual rectangular container. The effects of initial buoyancy ratio (R_ρ) on the instability pattern, the moving speed of the interface, energy accumulated during instability and the stability of the stratified system were studied by analyzing the stratification evolution and temperature response under different mass fraction differences and sidewall leakage. The study showed that with the increase of the initial buoyancy ratio, the instability pattern and the moving speed of the interface exhibit different laws, and the critical initial buoyancy ratio (R_ρc) keep the system stable. When the initial buoyancy was low (R_ρ≤0.35), the boundary floating flow could reach the liquid surface after penetrating the interface, the mixing area was located in the upper part of the upper liquid. The downward velocity of the interface was generally faster, but gradually slowed down later. When the initial buoyancy was high (0.47≤R_ρ≤R_ρc), the boundary floating flow could not reach the liquid surface, the mixing area was mainly located at the side of the upper liquid. The downward velocity of the interface was generally slower, but gradually accelerated later. Finally, it was found that with the increase of the initial buoyancy ratio, the interface penetration time was delayed, and the energy accumulated during instability was more. When the heat leakage rate was the same, a situation with the large initial mass fraction difference was more dangerous. When the mass fraction difference was the same, there may be a case with the low heat leak rate was more dangerous.

Key words: initial buoyancy ratio, stratification system, instability, convection, diffusion

摘要：

采用实验研究手段，在可视化矩形容器内构造多组分液体分层系统，通过分析不同质量分数差和侧壁漏热下容器内流体的分层演化规律和温度响应情况，揭示初始浮力比（R_ρ）对系统失稳形态、分界面移动速度、失稳积聚能量和分层系统稳定性的影响。结果表明随着初始浮力比的增大，分层结构失稳形态和分界面移动速度呈现不同规律，且存在临界初始浮力比（R_ρc）使分层系统保持稳定。当初始浮力比较低时（R_ρ≤0.35），边界浮升流穿透分界面后可到达液体表面，掺混区域位于上层液体上部，分界面下移速度整体较快，后期逐渐减慢；当初始浮力比较高时（0.47≤R_ρ≤R_ρc），边界浮升流不能到达液体表面，掺混区域主要位于上层液体侧部，分界面下移速度整体较慢，后期逐渐加快。同时发现，随着初始浮力比的增加，分界面穿透时间延后，分层失稳时积累能量越多，这导致漏热率相同时，初始质量分数差较大的情况更加危险；而质量分数差相同时，可能存在漏热率低而更危险的情况。

关键词: 初始浮力比, 分层系统, 不稳定性, 对流, 扩散

CLC Number:

Han ZHANG,Jingjie REN,Wei SHA,Yihui ZHOU,Mingshu BI. Effect of initial buoyancy ratio on stratification instability of multi-component liquids[J]. Chemical Industry and Engineering Progress, 2019, 38(10): 4481-4488.

张瀚,任婧杰,沙嵬,周一卉,毕明树. 初始浮力比对多组分液体分层失稳的影响[J]. 化工进展, 2019, 38(10): 4481-4488.

Figures/Tables 17

References 16

1	SARSTENJ A. LNG stratification and rollover [J]. Pipeline and Gas Journal, 1972, 199(11): 37-39.
2	MAKAYSSIT, LAMSAADIM, NAIMIM, et al. Natural double-diffusive convection in a shallow horizontal rectangular cavity uniformly heated and salted from the side and filled with non-Newtonian power-law fluids: the cooperating case [J]. Energy Conversion and Management, 2008, 49: 2016-2025.
3	KAMAKURAK, OZOEH. Three-dimensional analyses of double diffusive convection in a two-layer system at high Rayleigh number [J]. International Journal of Thermal Sciences, 2002, 41: 1045-1053.
4	王萍, 彭文山, 曹学文, 等. 大型LNG储罐储液翻滚特性的多阶段研究[J]. 石油工程建设, 2016, 42(1): 14-20.
	WANGPing, PENGWenshan, CAOXuewen, et al. Multi-stage study on rolling characteristics of liquid in large LNG storage tank [J]. Petroleum Engineering Construction, 2016, 42(1): 14-20.
5	VARMAS S, ATULSRIVASTAVA. Real-time two-color interferometric technique for simultaneous measurements of temperature and solutal fields [J]. International Journal of Heat and Mass Transfer, 2016, 98: 662-674.
6	TURNERJ S. The coupled turbulent transports of salt and heat across a sharp density interface [J]. Heat Mass Transfer, 1965, 8(5): 759-767.
7	石科峰, 卢文强. 双扩散对流条件下圆柱容器内温度场和浓度场分层现象[J]. 科学通报, 2006(4): 473-479.
	SHIKefeng, LUWenqiang. Temperature field and concentration field stratification in a cylindrical vessel under double diffusion convection conditions [J]. Chinese Science Bulletin, 2006(4): 473-479.
8	CHENZhiwu, ZHANJiemin, LIYoksheung, et al. Double-diffusive buoyancy convection in a square cuboid with horizontal temperature and concentration gradients [J]. International Journal of Heat and Mass Transfer, 2013, 60: 422-431.
9	李文婷, 李永放. 两层和多层结构中盐指现象的数值模拟[J]. 陕西师范大学学报(自然科学版), 2016, 44(3): 57-63.
	LIWenting, LIYongfang. Numerical study of salt-figuring phenomenon of bilayer and multilayer structure [J]. Journal of Shaanxi Normal University (Natural Science Edition), 2016, 44(3): 57-63.
10	VINCZEM, BORCIAI, HARLANDERU. Double-diffusive convection and baroclinic instability in a differentially heated and initially stratified rotating system: the barostrat instability [J]. Fluid Dynamic Research, 2016, 48: 061414.
11	POL S, FERNANDOH, WEBBS. Evolution of double-diffusive convection in low-aspect ratio containers [C]// APS Division of Fluid Dynamics Meeting. APS Division of Fluid Dynamics Meeting Abstracts, 2010.
12	REDDYC S. Numerical and experimental investigation of layer merging in double-diffusive convection in a slot [D]. Potsdam,NY:Clarksoh College of Technology,1977.
13	TAYLORR J, GEORGEV. Experiments on double-diffusive sugar-salt fingers at high stability ratio [J]. Journal of Fluid Mechanics, 1996, 321: 315-333.
14	SHAWei, RENJingjie, ZHANGHan, et al. Analysis of the interfacial instability and the patterns of rollover in multi-component layered system [J]. International Journal of Heat and Mass Transfer, 2018, 126: 235-242.
15	SHAWei, RENJingjie, WANGCheng, et al. Dynamic characteristics of the initial interface in stratified multi-composition liquid tanks during rollover [J]. Applied Thermal Engineering, 2018, 145: 396-406.
16	BERGMANT L, UNGANA. A note on lateral heating in a double-diffusive system [J]. Journal of Fluid Mechanics, 1988, 194: 175-186.

序号	侧壁/底部热通量 /W·m^-2	质量分数差 /%	初始浮力比 R_ρ
1	8000/2400	0.2	0.18
2	5500/2400	0.2	0.26
3	3000/2400	0.2	0.47
4	8000/2400	0.4	0.35
5	5500/2400	0.4	0.53
6	2650/2400	0.4	1.27
7	2550/2400	0.4	1.33
8	2440/2400	0.4	1.39
9	5500/2400	0.6	0.78
10	4060/2400	0.6	1.24
11	4000/2400	0.6	1.26
12	3000/2400	0.6	1.66
13	5500/2400	0.8	1.22
14	5450/2400	0.8	1.23
15	4000/2400	0.8	1.68

序号	侧壁/底部热通量 /W·m^-2	质量分数差 /%	初始浮力比 R_ρ
1	8000/2400	0.2	0.18
2	5500/2400	0.2	0.26
3	3000/2400	0.2	0.47
4	8000/2400	0.4	0.35
5	5500/2400	0.4	0.53
6	2650/2400	0.4	1.27
7	2550/2400	0.4	1.33
8	2440/2400	0.4	1.39
9	5500/2400	0.6	0.78
10	4060/2400	0.6	1.24
11	4000/2400	0.6	1.26
12	3000/2400	0.6	1.66
13	5500/2400	0.8	1.22
14	5450/2400	0.8	1.23
15	4000/2400	0.8	1.68

R_ρ	v₁	v₂	v₃	v₄	v₅	v₆	v₇	v₈	v₉	v₁₀
0.18（V形失稳）	3.12	3.71	3.55	3.71	2.44	2.36	2.60	2.05↓	2.17↓	1.81↓
0.26（W形失稳）	1.73	1.39	1.81	1.66	1.53	1.62	1.70	1.53↓	1.22↓	1.22↓
0.35（W形失稳）	1.90	2.05	2.29	2.00	2.00	1.73	1.86	1.62↓	1.39↓	1.30↓
0.47（X形失稳）	1.34	1.50	1.44	1.70	1.42	1.62	1.56	1.70	1.81	1.34
0.53（X形失稳）	1.20	1.01	1.08	1.22	1.16	1.22	1.08	1.20	1.01	0.92
0.78（X形失稳）	0.60	0.69	0.75	0.84	0.85	0.83	0.83	0.91	0.81	0.74
1.22（X形失稳）	0.43	0.48	0.52	0.49	0.57	0.61	0.54	0.65	0.46	0.61
1.24（X形失稳）	0.58	0.62	0.64	0.67	0.77	0.76	0.70	0.72	0.67	0.81
1.27（X形失稳）	0.65	0.80	0.92	0.81	0.92	1.07	0.93	0.85	1.28↑	1.39↑
1.33（X形失稳）	0.56	0.72	0.91	0.88	0.94	0.99	0.92	0.96↑	1.03↑	1.28↑

R_ρ	v₁	v₂	v₃	v₄	v₅	v₆	v₇	v₈	v₉	v₁₀
0.18（V形失稳）	3.12	3.71	3.55	3.71	2.44	2.36	2.60	2.05↓	2.17↓	1.81↓
0.26（W形失稳）	1.73	1.39	1.81	1.66	1.53	1.62	1.70	1.53↓	1.22↓	1.22↓
0.35（W形失稳）	1.90	2.05	2.29	2.00	2.00	1.73	1.86	1.62↓	1.39↓	1.30↓
0.47（X形失稳）	1.34	1.50	1.44	1.70	1.42	1.62	1.56	1.70	1.81	1.34
0.53（X形失稳）	1.20	1.01	1.08	1.22	1.16	1.22	1.08	1.20	1.01	0.92
0.78（X形失稳）	0.60	0.69	0.75	0.84	0.85	0.83	0.83	0.91	0.81	0.74
1.22（X形失稳）	0.43	0.48	0.52	0.49	0.57	0.61	0.54	0.65	0.46	0.61
1.24（X形失稳）	0.58	0.62	0.64	0.67	0.77	0.76	0.70	0.72	0.67	0.81
1.27（X形失稳）	0.65	0.80	0.92	0.81	0.92	1.07	0.93	0.85	1.28↑	1.39↑
1.33（X形失稳）	0.56	0.72	0.91	0.88	0.94	0.99	0.92	0.96↑	1.03↑	1.28↑

[1]	YANG Yudi, LI Wentao, QIAN Yongkang, HUI Junhong. Analysis of influencing factors of natural gas turbulent diffusion flame length in industrial combustion chamber [J]. Chemical Industry and Engineering Progress, 2023, 42(S1): 267-275.
[2]	XIAO Hui, ZHANG Xianjun, LAN Zhike, WANG Suhao, WANG Sheng. Advances in flow and heat transfer research of liquid metal flowing across tube bundles [J]. Chemical Industry and Engineering Progress, 2023, 42(S1): 10-20.
[3]	GU Yongzheng, ZHANG Yongsheng. Dynamic behavior and kinetic model of Hg⁰ adsorption by HBr-modified fly ash [J]. Chemical Industry and Engineering Progress, 2023, 42(S1): 498-509.
[4]	WU Zhanhua, SHENG Min. Pitfalls of accelerating rate calorimeter for reactivity hazard evaluation and risk assessment [J]. Chemical Industry and Engineering Progress, 2023, 42(7): 3374-3382.
[5]	ZHAO Yi, YANG Zhen, ZHANG Xinwei, WANG Gang, YANG Xuan. Molecular simulation of self-healing behavior of asphalt under different crack damage and healing temperature [J]. Chemical Industry and Engineering Progress, 2023, 42(6): 3147-3156.
[6]	LU Shijian, ZHANG Yuanyuan, WU Wenhua, YANG Fei, LIU Ling, KANG Guojun, LI Qingfang, CHEN Hongfu, WANG Ning, WANG Feng, ZHANG Juanjuan. Health risk assessment of nitrosamine pollutant diffusion in a million ton CO₂ capture project [J]. Chemical Industry and Engineering Progress, 2023, 42(6): 3209-3216.
[7]	GUO Wenjie, ZHAI Yuling, CHEN Wenzhe, SHEN Xin, XING Ming. Analysis of convective heat transfer and thermo-economic performance of Al₂O₃-CuO/water hybrid nanofluids [J]. Chemical Industry and Engineering Progress, 2023, 42(5): 2315-2324.
[8]	LU Xingfu, DAI Bo, YANG Shiliang. Super-quadric discrete element method investigation of mixing behaviors of cylindrical particles in a rotating drum [J]. Chemical Industry and Engineering Progress, 2023, 42(5): 2252-2261.
[9]	XIONG Xin, SU Qingzong, NONG Zengyao, WANG Yaxiong. Visualization and numerical analysis of heat transfer enhancement in the shell and tube latent thermal energy storage unit by the heating method [J]. Chemical Industry and Engineering Progress, 2022, 41(9): 4635-4643.
[10]	ZHANG Chunwei, LI Shanfeng, GUO Yongzhao, ZHANG Xuejun, JIANG Long. Gravity effect on PCM melting process under constant heat flux boundary [J]. Chemical Industry and Engineering Progress, 2022, 41(8): 4129-4139.
[11]	ZHU Mengshuai, WANG Zilong, SUN Xiangxin, ZHOU Xiang. Experimental research on effect of copper metal foam proportion on paraffin wax melting and heat transfer mechanism under high cell density [J]. Chemical Industry and Engineering Progress, 2022, 41(6): 3203-3211.
[12]	ZHOU Chilou, HE Mohan, GUO Jin, LI Yunquan, WU Hao, XIAO Shu, CHEN Guohua, OUYANG Ruixiang, HE Shi. Review on hydrogen embrittlement of austenitic stainless steel weldments in high pressure hydrogen atmosphere [J]. Chemical Industry and Engineering Progress, 2022, 41(2): 519-536.
[13]	LI Zhenghan, TU Zhengkai. Research progress of simulation models of proton exchange membrane fuel cell [J]. Chemical Industry and Engineering Progress, 2022, 41(10): 5272-5296.
[14]	YIN Shaowu, KANG Peng, HAN Jiawei, ZHANG Chao, WANG Li, TONG Lige. Thermal management performance of lithium-ion battery based on phase change materials [J]. Chemical Industry and Engineering Progress, 2022, 41(10): 5518-5529.
[15]	GAO Ya, XU Dan, WANG Shuyuan, ZHU Di. Recent progress in fabrication of high efficient catalysts by atomic layer deposition [J]. Chemical Industry and Engineering Progress, 2021, 40(8): 4242-4252.