垂直上升管内超临界二氧化碳传热恶化机理分析

doi:10.11949/0438-1157.20230472

摘要/Abstract

摘要：

超临界二氧化碳（SCO₂）流动传热过程中会发生传热恶化现象，领域内对该现象产生的机理仍存在较大争议。针对现有提出的四类不同的传热恶化机理，通过数值模拟研究，分析在不同工况下内径为5 mm的垂直上升管流动传热过程，从微观层面探究传热恶化机理。研究结果表明，四类机理观点中浮升力效应能更好地解释传热恶化现象，其他三类均具有一定的局限性。SCO₂传热恶化现象主要由密度变化引起的浮升力效应导致，当前工况下忽略重力影响时，传热恶化消失。浮升力效应通过改变内部流场的湍流结构，降低了湍动能的产生（层流化），湍流热扩散作用削弱使得传热效率下降，导致了传热恶化现象。研究结果对于SCO₂传热恶化的理论研究和预测关联式具有一定的指导意义。

关键词: 超临界二氧化碳, 数值模拟, 传热恶化, 浮升力, 传热

Abstract:

The phenomenon of heat transfer deterioration occurs during the heat transfer process of supercritical carbon dioxide (SCO₂) flow, and there is still significant controversy in the field about the mechanism. Based on the four different types of heat transfer deterioration mechanisms proposed, numerical simulation research is conducted to analyze the flow and heat transfer process of a vertical upward tube with an inner diameter of 5 mm under different operating conditions, and to explore the heat transfer deterioration mechanism from a microscopic perspective. The research results indicate that the heat transfer deterioration of SCO₂ is mainly caused by the buoyancy effect caused by density changes. When the influence of gravity is ignored, the heat transfer deterioration disappears. The buoyancy effect reduces the generation of turbulent kinetic energy (laminarization) by changing the turbulent flow structure of the internal flow field, and the weakening of turbulent thermal diffusion reduces the heat transfer efficiency, leading to the deterioration of heat transfer. The research results have certain guiding significance for the theoretical research and prediction correlation of heat transfer deterioration in supercritical carbon dioxide_.

Key words: supercritical carbon dioxide, numerical simulation, heat transfer deterioration, buoyancy, heat transfer

中图分类号:

TK 124

洪瑞, 袁宝强, 杜文静. 垂直上升管内超临界二氧化碳传热恶化机理分析[J]. 化工学报, 2023, 74(8): 3309-3319.

Rui HONG, Baoqiang YUAN, Wenjing DU. Analysis on mechanism of heat transfer deterioration of supercritical carbon dioxide in vertical upward tube[J]. CIESC Journal, 2023, 74(8): 3309-3319.

图/表 18

图1 压力为7.58 MPa下超临界二氧化碳热物性随温度的变化

Fig.1 Physical property variations near the pseudo-critical region for SCO2 at 7.58 MPa

图2 物理模型和边界条件设置

Fig.2 Physical model and boundary condition settings

表1 湍流模型中的常数

Table 1 Constants in the turbulence model

常数	Abe-Kondoh-Nagano (1994) （AKN模型)	Modified model^[22] (VAKN模型)
C_μ	0.09	0.09
C_ε₁	1.5	1.5
C_ε₂	1.9	1.9
σ_k	1.4	1.4
σ_ε	1.4	1.4
C_t1	—	1
C_t2	—	0.4
C_t3	—	-1.5

图3 垂直圆管模型网格无关性验证

Fig.3 Mesh independence verification of upward tube model

图4 湍流模型验证

Fig.4 Turbulence model validation

表2 仿真工况设计

Table 2 Simulation case setting

工况	流动传热条件	对流类型
Case A	Case 1（基本工况）	混合对流
Case B	密度变化，冻结其他物性	混合对流
Case C	黏度变化，冻结其他物性	强迫对流
Case D	比热容变化，冻结其他物性	强迫对流
Case E	密度冻结	强迫对流
Case F	不受重力	强迫对流
Case G	恒壁温	强迫对流
Case H	流动方向与Case A相反	混合对流

图5 不同工况下壁温和主流温度的沿程分布情况

Fig.5 Distributions of local inner wall temperature and bulk fluid temperature along the tube length in different cases

图6 不同工况下壁温、对流传热系数和Nu的沿程分布情况

Fig.6 Distributions of local inner wall temperature, convective heat transfer coefficient and Nu along the tube length in different cases

图7 Case A和Case F的壁温、主流温度和Nu的沿程分布情况

Fig.7 Distributions of local inner wall temperature, bulk fluid temperature and Nu along the tube length in Case A and Case F

图8 点P1、P2、P3处轴向速度沿径向分布情况

Fig.8 Profiles of axial velocity for different points

图9 点P1、P2、P3处湍动能沿径向分布情况

Fig.9 Profiles of turbulent kinetic energy for different points

图10 Case A各截面轴向速度的沿程分布情况

Fig.10 Profiles of axial velocity for different positions in Case A

图11 Case A、Case H壁温随沿程分布情况

Fig.11 Distributions of local inner wall temperature along the tube length in Case A and Case H

图12 Case A、Case F和Case H类气膜厚度及壁温随沿程分布情况

Fig.12 Distributions of gas-like film thickness and wall temperature along the tube length in Case A, Case F and Case H

图13 Case A径向速度的分布情况

Fig.13 Profiles of radial velocity in Case A

图14 Case A流体密度的径向分布情况

Fig.14 Profiles of density in Case A

图15 Case A湍动能总产生量的径向分布情况

Fig.15 Profiles of Pk and Gk term in Case A

图16 Case A湍动能沿径向分布情况

Fig.16 Profiles of turbulent kinetic energy in Case A

参考文献 32

1	Liang Y C, Sun Z L, Dong M R, et al. Investigation of a refrigeration system based on combined supercritical CO₂ power and transcritical CO₂ refrigeration cycles by waste heat recovery of engine[J]. International Journal of Refrigeration, 2020, 118: 470-482.
2	Duschek W, Kleinrahm R, Wagner W. Measurement and correlation of the (pressure, density, temperature) relation of carbon dioxide ( Ⅱ ) : Saturated-liquid and saturated-vapour densities and the vapour pressure along the entire coexistence curve[J]. The Journal of Chemical Thermodynamics, 1990, 22(9): 841-864.
3	Liu Y P, Wang Y, Huang D G. Supercritical CO₂ Brayton cycle: a state-of-the-art review[J]. Energy, 2019, 189: 115900.
4	黄彦平, 王俊峰. 超临界二氧化碳在核反应堆系统中的应用[J]. 核动力工程, 2012, 33(3): 21-27.
	Huang Y P, Wang J F. Applications of supercritical carbon dioxide in nuclear reactor system[J]. Nuclear Power Engineering, 2012, 33(3): 21-27.
5	Duffey R B, Pioro I L. Experimental heat transfer of supercritical carbon dioxide flowing inside channels (survey)[J]. Nuclear Engineering and Design, 2005, 235(8): 913-924.
6	Fan Y H, Tang G H. Numerical investigation on heat transfer of supercritical carbon dioxide in a vertical tube under circumferentially non-uniform heating[J]. Applied Thermal Engineering, 2018, 138: 354-364.
7	张良, 朱兵国, 吴新明, 等. 超临界二氧化碳在垂直光管内的传热特性[J]. 中国电机工程学报, 2019, 39(15): 4487-4497.
	Zhang L, Zhu B G, Wu X M, et al. Heat transfer characteristics of supercritical pressure CO₂ in a vertical smooth tube[J]. Proceedings of the CSEE, 2019, 39(15): 4487-4497.
8	Zhang Q, Li H X, Lei X L, et al. Study on identification method of heat transfer deterioration of supercritical fluids in vertically heated tubes[J]. International Journal of Heat and Mass Transfer, 2018, 127: 674-686.
9	He J D, Yan J J, Wang W, et al. Effects of buoyancy and thermophysical property variations on the flow of supercritical carbon dioxide[J]. International Journal of Heat and Fluid Flow, 2020, 86: 108697.
10	汪森林, 李照志, 邵应娟, 等. 超临界二氧化碳垂直管内传热恶化数值模拟研究[J]. 化工学报, 2022, 73(3): 1072-1082.
	Wang S L, Li Z Z, Shao Y J, et al. Numerical simulation on heat transfer deterioration of supercritical carbon dioxide in vertical tube[J]. CIESC Journal, 2022, 73(3): 1072-1082.
11	Holman J P, Rea S N, Howard C E. Forced convection heat transfer to Freon 12 near the critical state in a vertical annulus[J]. International Journal of Heat and Mass Transfer, 1965, 8(8): 1095-1102.
12	Zhu B G, Xu J L, Wu X M, et al. Supercritical “boiling” number, a new parameter to distinguish two regimes of carbon dioxide heat transfer in tubes[J]. International Journal of Thermal Sciences, 2019, 136: 254-266.
13	Zhu B G, Xu J L, Yan C S, et al. The general supercritical heat transfer correlation for vertical up-flow tubes: K number correlation[J]. International Journal of Heat and Mass Transfer, 2020, 148: 119080.
14	Zhang H S, Zhu X J, Zhu B G, et al. Effects of buoyancy and acceleration on heat transfer of supercritical CO₂ flowing in tubes[J]. Acta Physica Sinica, 2020, 69(6): 064401.
15	Zhang H S, Xu J L, Wang Q Y, et al. Multiple wall temperature peaks during forced convective heat transfer of supercritical carbon dioxide in tubes[J]. International Journal of Heat and Mass Transfer, 2021, 172: 121171.
16	Hall W B, Jackson J D, Watson A. Mixed forced and free convective heat transfer to supercritical pressure fluids flowing in vertical pipes[J]. Proceedings of the Institution of Mechanical Engineers, Conference Proceedings, 1967, 182(9): 10-22.
17	Bae J H, Yoo J Y, Choi H. Direct numerical simulation of turbulent supercritical flows with heat transfer[J]. Physics of Fluids, 2005, 17(10): 105104.
18	Licht J, Anderson M, Corradini M. Heat transfer and fluid flow characteristics in supercritical pressure water[J]. Journal of Heat Transfer, 2009, 131(7): 072502.
19	Kumar N, Basu D N. Role of buoyancy on the thermalhydraulic behavior of supercritical carbon dioxide flow through horizontal heated minichannel[J]. International Journal of Thermal Sciences, 2021, 168: 107051.
20	Lei Y C, Xu B, Chen Z Q. Experimental investigation on cooling heat transfer and buoyancy effect of supercritical carbon dioxide in horizontal and vertical micro-channels[J]. International Journal of Heat and Mass Transfer, 2021, 181: 121792.
21	Zhu X J, Zhang R Z, Du X, et al. Experimental study on heat transfer deterioration of supercritical CO₂ in a round tube: a boundary assessment[J]. International Communications in Heat and Mass Transfer, 2022, 134: 106055.
22	Jiang P X, Wang Z C, Xu R N. A modified buoyancy effect correction method on turbulent convection heat transfer of supercritical pressure fluid based on RANS model[J]. International Journal of Heat and Mass Transfer, 2018, 127: 257-267.
23	张宇, 姜培学, 石润富, 等. 竖直圆管中超临界压力CO₂在低Re数下对流换热研究[J]. 工程热物理学报, 2008, 29(1): 118-120.
	Zhang Y, Jiang P X, Shi R F, et al. Convection heat transfer of CO₂ at supercritical pressures in a vertical tube at low Reynolds numbers[J]. Journal of Engineering Thermophysics, 2008, 29(1): 118-120.
24	Fewster J. Mixed forced and free convective heat transfer to supercritical pressure fluids flowing in vertical pipes[D]. Manchester: University of Manchester, 1976.
25	Xie J Z, Liu D C, Yan H B, et al. A review of heat transfer deterioration of supercritical carbon dioxide flowing in vertical tubes: heat transfer behaviors, identification methods, critical heat fluxes, and heat transfer correlations[J]. International Journal of Heat and Mass Transfer, 2020, 149: 119233.
26	Pidaparti S R, McFarland J A, Mikhaeil M M, et al. Investigation of buoyancy effects on heat transfer characteristics of supercritical carbon dioxide in heating mode[J]. Journal of Nuclear Engineering and Radiation Science, 2015, 1(3): 031001.
27	Kurganov V A, Zeigarnik Y A, Maslakova I V. Heat transfer and hydraulic resistance of supercritical-pressure coolants ( Ⅰ ) : Specifics of thermophysical properties of supercritical pressure fluids and turbulent heat transfer under heating conditions in round tubes (state of the art)[J]. International Journal of Heat and Mass Transfer, 2012, 55(11/12): 3061-3075.
28	Lei X L, Peng R F, Guo Z M, et al. Experimental comparison of the heat transfer of carbon dioxide under subcritical and supercritical pressures[J]. International Journal of Heat and Mass Transfer, 2020, 152: 119562.
29	Kim D E, Kim M H. Experimental investigation of heat transfer in vertical upward and downward supercritical CO₂ flow in a circular tube[J]. International Journal of Heat and Fluid Flow, 2011, 32(1): 176-191.
30	Jackson J D. Models of heat transfer to fluids at supercritical pressure with influences of buoyancy and acceleration[J]. Applied Thermal Engineering, 2017, 124: 1481-1491.
31	Kim D E, Kim M H. Experimental study of the effects of flow acceleration and buoyancy on heat transfer in a supercritical fluid flow in a circular tube[J]. Nuclear Engineering and Design, 2010, 240(10): 3336-3349.
32	Bae Y Y. Mixed convection heat transfer to carbon dioxide flowing upward and downward in a vertical tube and an annular channel[J]. Nuclear Engineering and Design, 2011, 241(8): 3164-3177.

编辑推荐 0

Metrics

阅读次数

全文

756

HTML			PDF

最新录用	在线预览	正式出版	最新录用	在线预览	正式出版
1	0	6	52	0	697

来源	本网站	其他网站

次数	168	588
比例	22%	78%

摘要

574

最新录用	在线预览	正式出版

28	0	546

来源	本网站	其他网站

次数	119	455
比例	21%	79%

[1]	叶展羽, 山訸, 徐震原. 用于太阳能蒸发的折纸式蒸发器性能仿真[J]. 化工学报, 2023, 74(S1): 132-140.
[2]	张双星, 刘舫辰, 张义飞, 杜文静. R-134a脉动热管相变蓄放热实验研究[J]. 化工学报, 2023, 74(S1): 165-171.
[3]	张义飞, 刘舫辰, 张双星, 杜文静. 超临界二氧化碳用印刷电路板式换热器性能分析[J]. 化工学报, 2023, 74(S1): 183-190.
[4]	陈爱强, 代艳奇, 刘悦, 刘斌, 吴翰铭. 基板温度对HFE7100液滴蒸发过程的影响研究[J]. 化工学报, 2023, 74(S1): 191-197.
[5]	刘明栖, 吴延鹏. 导光管直径和长度对传热影响的模拟分析[J]. 化工学报, 2023, 74(S1): 206-212.
[6]	王志国, 薛孟, 董芋双, 张田震, 秦晓凯, 韩强. 基于裂隙粗糙性表征方法的地热岩体热流耦合数值模拟与分析[J]. 化工学报, 2023, 74(S1): 223-234.
[7]	宋嘉豪, 王文. 斯特林发动机与高温热管耦合运行特性研究[J]. 化工学报, 2023, 74(S1): 287-294.
[8]	张思雨, 殷勇高, 贾鹏琦, 叶威. 双U型地埋管群跨季节蓄热特性研究[J]. 化工学报, 2023, 74(S1): 295-301.
[9]	晁京伟, 许嘉兴, 李廷贤. 基于无管束蒸发换热强化策略的吸附热池的供热性能研究[J]. 化工学报, 2023, 74(S1): 302-310.
[10]	程成, 段钟弟, 孙浩然, 胡海涛, 薛鸿祥. 表面微结构对析晶沉积特性影响的格子Boltzmann模拟[J]. 化工学报, 2023, 74(S1): 74-86.
[11]	李艺彤, 郭航, 陈浩, 叶芳. 催化剂非均匀分布的质子交换膜燃料电池操作条件研究[J]. 化工学报, 2023, 74(9): 3831-3840.
[12]	王玉兵, 李杰, 詹宏波, 朱光亚, 张大林. R134a在菱形离散肋微小通道内的流动沸腾换热实验研究[J]. 化工学报, 2023, 74(9): 3797-3806.
[13]	齐聪, 丁子, 余杰, 汤茂清, 梁林. 基于选择吸收纳米薄膜的太阳能温差发电特性研究[J]. 化工学报, 2023, 74(9): 3921-3930.
[14]	李科, 文键, 忻碧平. 耦合蒸气冷却屏的真空多层绝热结构对液氢储罐自增压过程的影响机制研究[J]. 化工学报, 2023, 74(9): 3786-3796.
[15]	何松, 刘乔迈, 谢广烁, 王斯民, 肖娟. 高浓度水煤浆管道气膜减阻两相流模拟及代理辅助优化[J]. 化工学报, 2023, 74(9): 3766-3774.