螺旋翅片对于相变储能装置的强化传热有显著作用,以传统螺旋翅片为基础,使用4种不同压缩比的螺旋翅片分析翅片数目对相变材料凝固的影响。首先通过数值模拟对具有不同压缩比的螺旋翅片型储能罐中的相变材料凝固过程进行研究,并分析4个罐体内部温度分布以及相变界面随时间的变化情况。其次,分析液相分数、平均温度、总放热量、凝固时间和平均放热速率。最后,对比不同传热翅片数量对相变材料的影响。研究结果表明,设计压缩比合适的螺旋翅片可有效促进储能装置相变材料的凝固,减轻下部温度垂直分层现象,优化相变储能罐的放热性能。压缩比为3的储能罐中的相变材料平均放热速率与标准储能罐相比较,发现平均放热速率由86.7 J/s提升到93.9 J/s,增幅达8.7%;同时全部凝固所需时间减少6.6%。压缩比为5和7时,平均放热速率分别下降到84.7 J/s和63.8 J/s,分别下降2.3%和26.4%;完全凝固时间分别增加18%和38.7%。在相变材料（PCM）体积恒定情况下,翅片数量为8、10和12的储能罐的整体完成放热,翅片数量为14的储能罐放热效果反而不如翅片数量为6时,表明螺旋圈数并不是越多越好。凝固速度随着压缩比和翅片数量的增加呈先上升后下降的变化趋势,完全凝固所需的时间则是先减小后增加。
Abstract
Spiral fins play a significant role in enhancing heat transfer in phase-change energy storage devices. Four types of spiral fins with different compression ratios were used to analyze the effect of the number of fins on the solidification of phase change materials. First, the solidification process of the phase change material in the spiral fin energy storage tank with different compression ratios was numerically simulated, and the temperature distribution and change in the phase change interface in the four energy storage tanks with time were discussed. Second, the liquid phase fraction, average temperature, total heat release, solidification time, and average heat release rate were analyzed. The results indicate that the design of spiral fins with an appropriate compression ratio can effectively promote the solidification of phase-change materials in energy storage devices, reduce the phenomenon of vertical stratification at lower temperatures, and optimize the heat release performance of phase-change energy storage tanks. Compared with the standars energy storage tank, the average heat release rate of paraffin wax in the energy storage tank with a compression ratio of 3 increases from 86.7 J/s to 93.9 J/s, representing an increase of 8.7%. The complete solidification time is reduced by 6.6%. When the compression ratio is 5 and 7, the average heat release rate decreases to 84.7 J/s and 63.8 J/s, representing a decrease of 2.3% and 26.4%, respectively. The complete solidification time increases by 18% and 38.7%, respectively. For a constant volume of PCM, the energy storage tanks with 8, 10, and 12 fins completes the heat release as a whole, and the heat release effect of the energy storage tank with 14 fins is not as good as that of the tank with 6 fins, indicating that more spiral turns are not always better. As the compression ratio and number of fins increase, the solidification rate initially increases and then decreases, while the time required for complete solidification decreases before increasing again.
关键词
相变材料 /
传热性能 /
压缩比 /
螺旋翅片 /
翅片数量
Key words
phase change materials /
heat transfer performance /
compression ratio /
spiral fins /
number of fins
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 吉锌格, 李慧, 叶林, 等. 基于波动特性挖掘的短期光伏功率预测[J]. 太阳能学报, 2022, 43(5): 146-155.
JI X G, LI H, YE L, et al.Short-term photovoltaic power forecasting based on fluctuation characteristics mining[J]. Acta energiae solaris sinica, 2022, 43(5): 146-155.
[2] 代佳豪, 肖刚, 祝培旺, 等. 太阳能布雷顿循环耦合蓄电池平抑光伏输出波动策略研究[J]. 动力工程学报, 2023, 43(6): 717-723.
DAI J H, XIAO G, ZHU P W, et al.Study on fluctuation suppression strategy of solar brayton cycle with storage battery on photovoltaic output power[J]. Journal of Chinese Society of Power Engineering, 2023, 43(6): 717-723.
[3] 王冬晴, 庄云飞, 张滴滴, 等. 分级相变储放热系统在日光温室中的应用效果[J]. 太阳能学报, 2022, 43(12): 104-111.
WANG D Q, ZHUANG Y F, ZHANG D D, et al.Application effect of graded phase-change heat storage and release system in solar greenhouse[J]. Acta energiae solaris sinica, 2022, 43(12): 104-111.
[4] WU W, WANG X Y, XIA M, et al.A novel composite PCM for seasonal thermal energy storage of solar water heating system[J]. Renewable energy, 2020, 161: 457-469.
[5] SONI V, KUMAR A, JAIN V K.Performance evaluation of nano-enhanced phase change materials during discharge stage in waste heat recovery[J]. Renewable energy, 2018, 127: 587-601.
[6] KARAMI B, AZIMI N, AHMADI S.Increasing the electrical efficiency and thermal management of a photovoltaic module using expanded graphite (EG)/paraffin-beef tallow-coconut oil composite as phase change material[J]. Renewable energy, 2021, 178: 25-49.
[7] ANISH R, MARIAPPAN V, SURESH S.Experimental investigation on melting and solidification behaviour of erythritol in a vertical double spiral coil thermal energy storage system[J]. Sustainable cities and society, 2019, 44: 253-264.
[8] 张媛媛, 陈昆伦, 姚业成, 等. 相变填充床熔盐斜温层储热系统梯级储热特性[J]. 工程热物理学报, 2023, 44(3): 787-794.
ZHANG Y Y, CHEN K L, YAO Y C, et al.Cascade heat storage characteristics of multiphase molten salt thermocline heat storage system[J]. Journal of engineering thermophysics, 2023, 44(3): 787-794.
[9] ROZENFELD A, KOZAK Y, ROZENFELD T, et al.Experimental demonstration, modeling and analysis of a novel latent-heat thermal energy storage unit with a helical fin[J]. International journal of heat and mass transfer, 2017, 110: 692-709.
[10] KUMAR A, SAHA S K.Performance study of a novel funnel shaped shell and tube latent heat thermal energy storage system[J]. Renewable energy, 2021, 165: 731-747.
[11] BORHANI S M, HOSSEINI M J, RANJBAR A A, et al.Investigation of phase change in a spiral-fin heat exchanger[J]. Applied mathematical modelling, 2019, 67: 297-314.
[12] 薛洁, 张军, 杜昭, 等. 新型平底型相变蓄热器蓄热性能的数值模拟[J]. 储能科学与技术, 2022, 11(12): 3855-3861.
XUE J, ZHANG J, DU Z, et al.A numerical simulation study on the heat-storage performance of a flat-bottom heat storage tank[J]. Energy storage science and technology, 2022, 11(12): 3855-3861.
[13] MEHTA D S, VAGHELA B, RATHOD M K, et al.Heat transfer enhancement using spiral fins in different orientations of Latent Heat Storage Unit[J]. International journal of thermal sciences, 2021, 169: 107060.
[14] YUAN Y P, CAO X L, XIANG B, et al.Effect of installation angle of fins on melting characteristics of annular unit for latent heat thermal energy storage[J]. Solar energy, 2016, 136: 365-378.
[15] HE F, BO R F, HU C X, et al.Employing spiral fins to improve the thermal performance of phase-change materials in shell-tube latent heat storage units[J]. Renewable energy, 2023, 203: 518-528.
[16] MIAO X M, RIAZ F, ALOTAIBI B, et al.Performance enhancement of latent heat thermal energy storage system by using spiral fins in phase change material solidification process[J]. Process safety and environmental protection, 2023, 176: 568-579.
[17] SCIACOVELLI A, GAGLIARDI F, VERDA V.Maximization of performance of a PCM latent heat storage system with innovative fins[J]. Applied energy, 2015, 137: 707-715.
基金
河北省自然科学基金（2022502052; E2022502001）
PDF(4823 KB)
