Examination of the cross-seasonal phase-change heat storage performance of different U-shaped buried pipe structures

doi:10.19799/j.cnki.2095-4239.2023.0461

Abstract

Abstract:

Northern weather is characterized by typical cold winters and hot summers, with high light intensity in the summer, which is suitable for the development of solar vegetable greenhouse technology. However, winters are cold, and the use of vegetable greenhouses is subject to seasonal restrictions. To solve the problem of excess heat in summer and the insufficient heating temperature of vegetable greenhouses in winter, Fluent software is employed to simulate the heat storage of ordinary U-shaped buried pipes with a double wing, 90° double wing, four wing, 45° four wing, and six-wing U-shaped buried pipe heat accumulator in the summer, and the effects of different buried pipe structures on the heat storage performance are compared and investigated. The results reveal that the U-shaped buried pipe structure is distributed up and down, and when the fluid is up and down, the liquefaction area of the same wing-type U-shaped buried pipe structure is greater than that when it is finned longitudinally. The temperature of the backfill center position (i.e., x=0 m, y=0 m) reveals that longitudinal winging is greater than transverse winging, whereas lateral winging leads to an increase in the radial temperature. At the same time, the double-winged U-shaped buried pipe exhibits the highest liquid phase rate, while the 45° four-winged U-shaped buried pipe exhibits the lowest liquid phase rate. The six-winged U-shaped buried pipe exhibits the fastest heat storage, whereas the 45° four-winged U-shaped buried pipe exhibits the slowest heat storage. Different U-shaped buried pipe structures located in phase-change backfill materials considerably affect temperature. The heat storage of the winged U-shaped buried pipe is 15—39 MJ greater than that of the ordinary U-shaped buried pipe, the double-winged U-shaped buried pipe structure exhibits the highest heat storage, and the 45° four-wing U-shaped buried pipe exhibits the least heat storage.

Key words: buried pipes, cross-seasonal heat storage, phase change heat storage, numerical simulation

CLC Number:

TK 52

Chen WANG, Haiting CUI, Chao WANG, Yalei ZHANG, Haosong CHEN. Examination of the cross-seasonal phase-change heat storage performance of different U-shaped buried pipe structures[J]. Energy Storage Science and Technology, 2023, 12(12): 3808-3817.

Figures/Tables 14

Fig. 1

Fig. 2

Table 1

Fig. 3

Fig. 4

Table 2

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Fig. 12

References 23

1	赵兰, 王国珍. 相变蓄热复合传热强化技术综述[J]. 储能科学与技术, 2022, 11(11): 3534-3547.
	ZHAO L, WANG G Z. Research progress on composite heat transfer enhancement technology of phase change heat storage system[J]. Energy Storage Science and Technology, 2022, 11(11): 3534-3547.
2	杜昭, 阳康, 舒高, 等. 金属泡沫内石蜡固液相变蓄热/放热实验[J]. 储能科学与技术, 2022, 11(2): 531-537.
	DU Z, YANG K, SHU G, et al. Experimental study on the heat storage and release of the solid-liquid phase change in metal-foam-filled tube[J]. Energy Storage Science and Technology, 2022, 11(2): 531-537.
3	ZOU D Q, MA X F, LIU X S, et al. Research progress on graphene in phase change materials[J]. Chemical Industry and Engineering Progress, 2017, 36(5): 1743-1754.
4	刘丽辉, 莫雅菁, 孙小琴, 等. 纳米增强型复合相变材料的传热特性[J]. 储能科学与技术, 2020, 9(4): 1105-1112.
	LIU L H, MO Y J, SUN X Q, et al. Thermal behavior of the nanoenhanced phase change materials[J]. Energy Storage Science and Technology, 2020, 9(4): 1105-1112.
5	QI D, PU L, SUN F T, et al. Numerical investigation on thermal performance of ground heat exchangers using phase change materials as grout for ground source heat pump system[J]. Applied Thermal Engineering, 2016, 106: 1023-1032.
6	陈宝明, 张艳勇, 李佳阳. 铝/石蜡复合相变材料蓄热性能的数值模拟[J]. 热科学与技术, 2021, 20(6): 528-536.
	CHEN B M, ZHANG Y Y, LI J Y. Numerical simulation of heat storage performance of aluminum/paraffin composite phase change material[J]. Journal of Thermal Science and Technology, 2021, 20(6): 528-536.
7	杨慧慧, 曾立, 汤波, 等. 谷电利用复合石蜡蓄热材料的制备及供暖墙体构造实验[J]. 储能科学与技术, 2022, 11(1): 19-29.
	YANG H H, ZENG L, TANG B, et al. Experimental study on an EG/paraffin composite thermal storage material and its feasibility for off-peak power heating utilization[J]. Energy Storage Science and Technology, 2022, 11(1): 19-29.
8	邓婷婷, 蔡颖玲. 笼屉式水箱中膨胀石墨对石蜡熔化和凝固过程的影响[J]. 储能科学与技术, 2021, 10(1): 190-197.
	DENG T T, CAI Y L. Effect of expanded graphite on the melting and solidification of paraffin in cage water tank[J]. Energy Storage Science and Technology, 2021, 10(1): 190-197.
9	CLAESSON J, DUNAND A. Heat extraction from the ground by horizontal pipes: A mathematical analysis[M]. Stockholm: Swedish Council for Building Research, 1983
10	HUBER A, WETTER M. Vertical Borehole Heat Exchanger, EWS Model: TRNSYS Type 451[M]. ZTL-Luzern and Huber Energietechnik-Zvrich, 1997.
11	曾和义, 刁乃仁, 方肇洪. 竖直埋管地热换热器钻孔内的热阻[J]. 煤气与热力, 2003, 23(3): 134-138.
	ZENG H Y, DIAO N R, FANG Z H. Thermal resistance inside bore-holes of vertical geothermal heat exchangers[J]. Gas & Heat, 2003, 23(3): 134-138.
12	GUSTAFSSON A M, WESTERLUND L, HELLSTRÖM G. CFD-modelling of natural convection in a groundwater-filled borehole heat exchanger[J]. Applied Thermal Engineering, 2010, 30(6/7): 683-691.
13	HU P F, ZHA J, LEI F, et al. A composite cylindrical model and its application in analysis of thermal response and performance for energy pile[J]. Energy and Buildings, 2014, 84: 324-332.
14	ZHANG W K, YANG H X, LU L, et al. Investigation on heat transfer around buried coils of pile foundation heat exchangers for ground-coupled heat pump applications[J]. International Journal of Heat and Mass Transfer, 2012, 55(21/22): 6023-6031.
15	MAN Y, YANG H X, DIAO N R, et al. Development of spiral heat source model for novel pile ground heat exchangers[J]. HVAC&R Research, 2011, 17(6): 1075-1088.
16	PARK S, LEE S R, PARK H, et al. Characteristics of an analytical solution for a spiral coil type ground heat exchanger[J]. Computers and Geotechnics, 2013, 49: 18-24.
17	张永学, 王梓熙, 鲁博辉, 等. 雪花型翅片提高相变储热单元储/放热性能[J]. 储能科学与技术, 2022, 11(2): 521-530.
	ZHANG Y X, WANG Z X, LU B H, et al. Enhancement of charging and discharging performance of a latent-heat thermal-energy storage unit using snowflake-shaped fins[J]. Energy Storage Science and Technology, 2022, 11(2): 521-530.
18	王君雷, 徐祥贵, 孙通, 等. 一种螺旋翅片式相变储热单元的储热优化模拟[J]. 储能科学与技术, 2021, 10(2): 514-522.
	WANG J L, XU X G, SUN T, et al. Simulation of heat storage process in spiral fin phase change heat storage unit[J]. Energy Storage Science and Technology, 2021, 10(2): 514-522.
19	LOHRASBI S, MIRY S Z, GORJI-BANDPY M, et al. Performance enhancement of finned heat pipe assisted latent heat thermal energy storage system in the presence of nano-enhanced H₂O as phase change material[J]. International Journal of Hydrogen Energy, 2017, 42(10): 6526-6546.
20	杨卫波, 徐瑞, 杨晶晶, 等. 相变材料回填地埋管换热器热响应特性的数值模拟及试验验证[J]. 流体机械, 2019, 47(7): 72-79, 60.
	YANG W B, XU R, YANG J J, et al. Numerical simulation and experimental validation of the thermal response characteristics of ground heat exchanger with PCM backfill[J]. Fluid Machinery, 2019, 47(7): 72-79, 60.
21	于明志, 贺泽群, 毛煜东, 等. 地埋管换热器分区运行对地源热泵系统运行经济性影响的模拟研究[J]. 太阳能学报, 2022, 43(1): 205-212.
	YU M Z, HE Z Q, MAO Y D, et al. Influence of ground heat exchanger zoning operation on operation economy of ground source heat pump systems[J]. Acta Energiae Solaris Sinica, 2022, 43(1): 205-212.
22	唐文龙, 张季, 汪丽娟, 等. 土壤源热泵间歇运行条件下土壤换热特性分析[J]. 兰州工业学院学报, 2022, 29(6): 18-24.
	TANG W L, ZHANG J, WANG L J, et al. Analysis of soil heat transfer characteristics under intermittent operation of ground source heat pump[J]. Journal of Lanzhou Institute of Technology, 2022, 29(6): 18-24.
23	李启宇. 相变材料回填的地埋管的传热特性研究[D]. 上海: 东华大学, 2014.
	LI Q Y. Study on heat transfer characteristics of buried pipes backfilled with phase change materials[D]. Shanghai: Donghua University, 2014.

项目	密度/(kg/m³)	比热容 /[J/(kg·K)]	热导率 /[W/(m·K)]
循环水	1000	4200	0.6
U型地埋管	900	2300	0.35
相变材料(石墨-石蜡)	950	2000	0.2
土壤	2000	1000	2.2

网格数量	6 h时P点温度/℃	12 h时P点温度/℃
94969	30.6	31.3
137309	30.1	30.7
236859	29.7	30.4

[1]	Yanjun BO, Xinjie XUE, Huaning WANG, Changying ZHAO. System design and experimental study of Carnot battery based on latent heat/cold stores [J]. Energy Storage Science and Technology, 2023, 12(9): 2823-2832.
[2]	Kaifu LUAN, Changkun CAI, Manyi XIE, Chun ZHANG, Kuncan ZHENG, Shengli AN. Research progress of macroscale numerical simulation of fluid and thermal fields of solid oxide fuel cells [J]. Energy Storage Science and Technology, 2023, 12(9): 2985-3002.
[3]	Man CHEN, Zhixiang CHENG, Chunpeng ZHAO, Peng PENG, Qikai LEI, Kaiqiang JIN, Qingsong WANG. Numerical simulation study on explosion hazards of lithium-ion battery energy storage containers [J]. Energy Storage Science and Technology, 2023, 12(8): 2594-2605.
[4]	Jinghao YAN, Jie LI, Yiming LI, Xiaoqin SUN, Lina XI, Changwei JIANG. Numerical simulation study on heat storage performance of composite phase-change units based on gradient-porosity metal foam [J]. Energy Storage Science and Technology, 2023, 12(8): 2424-2434.
[5]	Yuxin CHEN, Jiamu YANG, Cheng LIAN, Honglai LIU. Analysis of stable coating window of lithium battery electrode paste based on phase field models [J]. Energy Storage Science and Technology, 2023, 12(7): 2185-2193.
[6]	Zian PENG, Wenchao DUAN, Jie LI, Xiaoqin SUN, Mengjie SONG. Energy storage characteristics of a shell-and-tube phase change energy storage heat exchanger for data centers [J]. Energy Storage Science and Technology, 2023, 12(6): 1765-1773.
[7]	Yongshuai YU, Yongfeng LIU, Pucheng PEI, Lu ZHANG, Shengzhuo YAO. Effect of cathode relative humidity on membrane water content and performance of PEMFC [J]. Energy Storage Science and Technology, 2023, 12(6): 1755-1764.
[8]	Yuxin CHEN, Jiamu YANG, Dongbo LI, Cheng LIAN, Honglai LIU. Numerical simulation of the vacuum drying process of cylindrical lithium-ion batteries [J]. Energy Storage Science and Technology, 2023, 12(6): 1957-1967.
[9]	Yalei ZHANG, Haiting CUI, Chen WANG, Haosong CHEN, Chao WANG. Research on a phase-change storage heating system of a solar-ground source heat pump based on low current [J]. Energy Storage Science and Technology, 2023, 12(12): 3789-3798.
[10]	Rui HAN, Zhirong LIAO, Boxu YU, Chao XU, Xing JU. Simulation study of a molten-salt Carnot battery energy storage system for retrofitting a thermal power plant [J]. Energy Storage Science and Technology, 2023, 12(12): 3605-3615.
[11]	Jixiang GE, Mingxi JI, Yulong DING, Yimo LUO, Liming WANG. Parameter optimization of a thermochemical reactor using salt hydrates： A case study of heating application [J]. Energy Storage Science and Technology, 2023, 12(12): 3799-3807.
[12]	Yanqin GUO, Zhen ZENG, Hongguang ZHANG, Ziye LING, Zhengguo ZHANG, Xiaoming FANG. Investigation of heat transfer enhancement mechanism and performance of phase change materials using expanded graphite in double helical coils [J]. Energy Storage Science and Technology, 2023, 12(12): 3678-3689.
[13]	Zhenwei TAN, Mu LI, Chuanchang LI. Research on the heat transfer characteristics of phase change cold storage gels in tube and fin cold storage equipment [J]. Energy Storage Science and Technology, 2023, 12(12): 3740-3748.
[14]	Jian CHANG, Hang SONG, Yuzhen KANG, Tao LU, Zhiwei TANG. Application of high-temperature composite phase change heat storage in urban clean energy transformation [J]. Energy Storage Science and Technology, 2023, 12(11): 3471-3478.
[15]	Keke LIU, Yongfeng LIU, Pucheng PEI, Shengzhuo YAO, Lu ZHANG. Design of a novel flow channel structure of PEMFC based on Koch snowflake [J]. Energy Storage Science and Technology, 2023, 12(11): 3361-3368.