Dynamic Heat Transfer Analysis on the New U-type Medium-Deep Borehole Ground Heat Exchanger

Frontiers in Energy Research - Tập 10
Chunmin Guan1, Zhaohong Fang1, Wenke Zhang1, Haiqing Yao2, Yi Man1, Mingzhi Yu1
1School of Thermal Engineering, China
2Shandong Zhongrui New Energy Technology Co. Ltd, China

Tóm tắt

The U-type medium-deep borehole ground heat exchanger BGHE is a new form of utilization of geothermal energy and there has been relatively little research on it. This paper introduces the structure and working principle of the BGHE. The energy control equations based on the characteristics of the heat transfer model are established creatively. The initial and boundary conditions of the circulating fluid and rock soil are determined. And the reliability of the simulation is verified through comparing the simulated results with the engineering data. Based on the above theoretical foundation, the effects of the circulating fluid flow rate, geothermal gradient and thermal conductivity of different soil layers on the nominal heat extraction and the outlet temperature of the U-type BGHE are examined. The temperature changes in the soil surrounding the vertical pipe and the temperature of circulating fluid at the inlet and outlet of the BGHE are analysed. The corresponding reasons of these changes are revealed. It is shown from simulation results that the circulating fluid flow rate has opposite influence on the nominal heat extraction and outlet temperature. The increasing terrestrial heat flow is conducive to heat transfer, but the reverse heat transfer occurs during the heat transfer process. The influence of the BGHE on the surrounding rock soil will hardly affect the continuous use of the buried ground heat exchanger. The results of the study are beneficial to better understand the heat transfer characteristics of the U-type medium-deep BGHE and its impact on the surrounding soil. It will promote the popularization and application of medium-deep geothermal energy.

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Tài liệu tham khảo

Cai, 2022, Long-term Performance Evaluation for Deep Borehole Heat Exchanger Array under Different Soil thermal Properties and System Layouts, Energy, 241, 122937, 10.1016/j.energy.2021.122937

Chu, 2021, Mine-oriented Low-Enthaply Geothermal Exploitation: A Review from Spatio-Temproal Perspective, Energ. Convers. Management, 237, 114123, 10.1016/j.enconman.2021.14123

Deng, 2020, Simulation Analysis on the Heat Performance of Deep Borehole Heat Exchangers in Medium-Depth Geothermal Heat Pump Systems, J. Energies, 13, 754, 10.3390/en13030754

Du, 2020, Heat Transfer Modeling and Heat Extraction Analysis of Casing Type Medium-Deep Buried Heat Exchanger, Renew. Energ. Resour., 38, 887

El Haj Assad, 2021, Heat Pumps and Absorption Chillers, Des. Perform. Optimization Renew. Energ. Syst., 11, 163, 10.1016/B978-0-12-821602-6.00013-4

Fan, 2022, Determining the Recoverable Geothermal Resources Using a Numerical Thermo-Hydraulic Coupled Modeling in Geothermal Reservoirs, Front. Earth Sci., 9, 787133, 10.3389/feart.2021.787133

He, 2001, Chemical Principles, 190

He, 2021, Performance Analysis of Coaxial Heat Exchanger and Heat-Carrier Fluid in Medium-Deep Geothermal Energy Development, Renew. Energ., 168, 10.1016/J.RENENE.2020.12.109

Jiao, 2022, Stratum Temperature Recovery Considering Groundwater Advection in Periodic Operations of Deep Borehole Heat Exchager, Appl. Therm. Eng., 206, 118113, 10.1016/j.applthermaleng.2022.118113

Li, 2019, Experimental and Numerical Studies on Heat Transfer Characteristics of Vertical Deep-Buried U-bend Pipe in Intermittent Heating Mode, Geothermics, 79, 14, 10.1016/j.geothermics.2019.01.001

Li, 2021, Heat Extraction Model and Characteristics of Coaxial Deep Borehole Heat Exchanger, Renew. Energ., 738, 10.1016/j.renene.2021.01.036

Liang, 2018, Heat Transfer Analysis and Application of Deep Borehole Heat Exchanger in Ground Source Heat Pump Systems, Doctoral Dissertation

Liu, 2019, Experimental Study of Deep Ground Source Heat Pump System and Optimization of Tube Well Structure, J. Eng. Thermophys., 40, 2143

Liu, 2019, Numerical Study on the Effects of Design Parameters on the Heat Transfer Performance of Coaxial Deep Borehole Heat Exchanger, Int. J. Energ. Res., 43, 1, 10.1002/er.4357

Luo, 2022, Analytical Modeling and thermal Analysis of Deep Coaxial Borehole Heat Exchanger with Stratified-Seepage-Segmented Finite Line Source Method (S3-fLS), Energy & Buildings, 111795, 10.1016/j.enbuild.2021.111795

Luo, 2020, Improved Analytical Modeling and System Performance Evaluation of Deep Coaxial Borehole Heat Exchanger with Segmented Finite cylinder-source Method, Energy and Buildings, 212, 109829, 10.1016/j.enbuild.2020.109829

Manzella, 2018, Environmental and Social Aspects of Geothermal Energy in Italy, Geothermics, 72, 232, 10.1016/j.geothermics.2017.11.015

Olasolo, 2016, Enhanced Geothermal Systems (EGS): A Review, J. Renew. Sustainable Energ. Rev., 56, 133, 10.1016/j.rser.2015.11.031

Sarbu, 2014, General Review of Ground-Source Heat Pump Systems for Heating and Cooling of Buildings, J. Energ. Buildings., 70, 441, 10.1016/j.enbuild.2013.11.068

Zhang, 2021, Heat Transfer Analysis of U-type Deep Borehole Heat Exchangers of Geothermal Energy, Energy & Buildings, 237, 110794, 10.1016/j.enbuild.2021.110794

Zhang, 2020, Key Heating Technology of "water Retention and Heat Extraction" for the Development of Deep Geothermal Energy in Guanzhong Basin, J. District Heat., 4, 122

Zheng, 2021, Geological Characteristics and Distribution of Granite Geothermal Reservoir in Southeast Coastal Areas in China, Front. Earth Sci., 9, 683696, 10.3389/feart.2021.683696

Zhou, 2019, Innovative Vertical U-Shaped Deep Buried Pipe Heating Heat Transfer Performance experiment, J. Technology Innovation Management, 40, 33

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Frontiers in Energy Research

Tập 10

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