Periodic heat flux composite model for borehole heat exchanger and its application.
发布时间：2023-04-22
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- 论文类型：
- 文章
- 第一作者：
- 雷飞
- 合写作者：
- 胡平放,朱娜,邬田华
- 发表刊物：
- Applied Energy
- 收录刊物：
- SCI
- 所属单位：
- 华中科技大学
- 刊物所在地：
- United Kingdom
- 学科门类：
- 工学
- 一级学科：
- 土木工程
- 文献类型：
- J
- 卷号：
- 151
- 页面范围：
- 132-142
- ISSN号：
- 0306-2619
- 关键字：
- Ground source heat pump;Borehole heat exchanger;Frequency response;Harmonic method;Frequency decomposition
- DOI码：
- 10.1016/j.apenergy.2015.04.035
- 发表时间：
- 2015-07-08
- 影响因子：
- 11.446
- 摘要：
- Most existing borehole heat exchanger models are based on constant heat flux solutions. This paper first proposes a periodic heat flux composite model for a borehole heat exchanger to reproduce the periodic nature of real loads. An explicit analytical solution of a periodic cylinder-source in composite media is derived using a harmonic method. The periodic thermal response factor is defined to characterize the thermal behaviour of a borehole subjected to a periodic heat flux. The periodic thermal responses factors for high- and low-frequency periodic heat flux are dominantly determined by the thermal properties of the content inside the borehole and the ground outside the borehole, respectively. A frequency decomposition hybrid algorithm is specially designed according to the frequency response characteristic of borehole. The proposed periodic heat flux model is verified through an inter-model comparison with existing constant heat flux models and the comparison indicates an equivalent relationship between the two types of models. An annual simulation is performed using the hybrid algorithm and the accuracy of the algorithm is verified. The paper also presents a new method to analyse the data of an oscillatory thermal response test by using the periodic composite model. The effective heat capacities of the ground and grout are estimated. The simulation results of the periodic composite model are in good agreement with the experimental data. (C) 2015 Elsevier Ltd. All rights reserved.