Chongqing Vocational Institute of Engineering, Chongqing, China.
China Railway Construction Bridge Engineering Bureau Group CO., LTD, Tianjin, China.
PLoS One. 2024 May 14;19(5):e0298077. doi: 10.1371/journal.pone.0298077. eCollection 2024.
Geothermal energy is increasingly employed across diverse applications, with bridge deck snow melting emerging as a notable utilization scenario. In Jinan city, China, a project is underway to utilize ground source heat pumps (GSHPS) for heating bridges. However, essential operational parameters, including fluid medium, temperature, and heat exchange details, are currently lacking. This study addresses the thermal design challenges associated with ground heat exchangers (GHE) for bridge heating through a combination of numerical modeling and field experiments. Utilizing software Fluent, a refined three-dimensional multi-condition heat transfer numerical analysis was carried out. Field tests based on actual operating conditions were also conducted and the design parameters were verified. The results indicate that an inlet temperature of 5°C and an aqueous solution of ethylene glycol with a mass concentration of 35% as the heat exchange medium are suitable for the GSHPS in Jinan; Moreover, the influence of backfill material and operation time on the heat transfer efficiency was revealed and the suitable material with 10% bentonite and 90% SiO2 was suggested; Finally, based on the influence of the pipe spacing on the heating characteristics of bridge deck, the transition spacing of 0.2 m is given for the temperature response of the bridge deck. This comprehensive study contributes valuable insights through simulation and experimental analysis of the thermal environment variation, aiming to advance the development of GSHPS for bridge deck heating in Jinan, China.
地热能在各种应用中得到了越来越多的应用，其中桥面融雪就是一个值得注意的应用场景。在中国济南市，一个利用地源热泵（GSHP）为桥梁供暖的项目正在进行中。然而，目前还缺乏必要的运行参数，包括流体介质、温度和热交换细节。本研究通过数值模拟和现场实验相结合，解决了桥梁加热用地下换热器（GHE）的热设计挑战。利用 Fluent 软件，对三维多工况传热进行了精细化数值分析。还进行了基于实际运行条件的现场测试，并验证了设计参数。结果表明，入口温度为 5°C，质量浓度为 35%的乙二醇水溶液作为热交换介质，适用于济南的 GSHP；此外，揭示了回填材料和运行时间对传热效率的影响，并建议使用 10%膨润土和 90%SiO2 的合适材料；最后，根据管间距对桥面加热特性的影响，给出了桥面温度响应的 0.2m 过渡间距。本研究通过对热环境变化的模拟和实验分析，为中国济南市的桥面融雪用 GSHP 的发展提供了有价值的见解。
