随着矿山开采形成的采空区、巷道等地下空间日益增多，地下空间资源的开发利用已经成为国家的发展方向，同时太阳能以及附近工厂余热也属于资源开发的范畴。为了实现地下空间和太阳能资源的协同开发利用，本文提出对地下空间进行充填并以其作为跨季节热储库的新方法。通过对地下矿井空间进行充填，可有效的遏制地表塌陷，保护地下水资源。向充填体内添加相变材料并通过换热流体将太阳能储存在充填体内，有利于提高充填体的蓄热性能，同时实现太阳能的跨季节储存。

本文通过充填体蓄热/释热实验研究换热流体运行参数、充填体初始温度、蓄热/释热时间比等对换热性能的影响。实验研究发现充填体初始温度降低和蓄热温度增加，有利于充填体的换热性能的提升。当初始温度从55℃降低到25℃，蓄热量增幅为141%，释热量降幅为10.6%。当蓄热温度由70℃增加到90℃时，蓄热/释热量增幅分别为68.3%、25.9%。蓄热/释热时间比2:1（蓄热总时间为400min），当蓄热时间为200min时，蓄热量可以达到总蓄热量的80%。

通过模拟研究在实际尺寸充填体中保温材料厚度、充填体初始温度以及相变材料比例对充填体热性能以及热泄漏的影响。研究发现：相变材料比例以及充填体初始温度对充填体换热性能影响较大；释热量、相变材料液相率以及能效系数随着充填体初始温度的增大而增大，而蓄热量以及热损失量随着初始温度的增加而降低。当充填体采取保温措施后，释热量增幅为36.58%-41.45%，能效系数由59.55%增加到84.46%以上。相变材料比例为20%的充填体相比于常规充填体，蓄热量由56.64×10⁶kJ增加到85.27×10⁶kJ，释热量由48.54×10⁶kJ增加到68.2×10⁶kJ，增幅分别为50.5%、40.5%。

本研究结果为实现地下空间利用以及跨季节储热提供了理论参考，为充填体跨季节储热中换热参数的选择提供了基础数据。

With the development of the mine, the underground space such as goaf and roadway formed in the mining process is gradually enlarging. Therefore, the utilization of underground space has become the direction of the country. At the same time, solar energy and factory waste heat also belong to the category of resource development. Aiming at the utilization of underground mine space and the seasonal storage of solar energy, this paper proposes a new method to fill the underground space and use it as a cross-seasonal thermal reservoir. Filling the underground mine space can effectively curb surface subsidence and protect groundwater resources. Adding composite phase change materials to the filling body and storing solar energy in the filling body through heat transfer fluid is beneficial to improve the heat transfer performance of the filling body and realize the cross-seasonal storage of solar energy.

In this paper, the influence of heat transfer fluid, initial temperature of filling body, heat storage / release time ratio and other parameters on heat storage / release performance was studied by heat storage/release experiment of filling body. The experimental study found that the decrease of the initial temperature of the filling body and the increase of the heat storage temperature are beneficial to the improvement of the heat transfer performance of the filling body. The heat storage capacity increases by 141 % and the heat release capacity decreases by 10.6 % when the initial temperature decreases from 55 °C to 25 °C. The heat storage / release capacity increases by 68.3 % and 25.9 % when the heat storage temperature increases from 70 °C to 90 °C. The heat storage / release time ratio is 2:1 (the total heat storage time is 400min), the heat storage can reach 80 % of the total heat storage capacity when the heat storage capacity time is 200min.

The effects of the thickness of the insulation material, the initial temperature of the filling body and the addition ratio of the CPCM on the thermal performance and thermal leakage of the filling body in the actual size filling body were studied by simulation. It is found that the addition ratio of PCM and the initial temperature of the filling body have a great influence on the heat transfer performance. The heat release capacity and energy efficiency coefficient increase with the increase of the initial temperature of the filling body, while the heat storage capacity and heat loss capacity decrease with the increase of the initial temperature. After adding thermal insulation materials around the filling body, the heat release capacity increases by 36.58 %-41.45 %, and the energy efficiency coefficient increases from 59.55 % to more than 84.46 %. Compared with the conventional filling body, the heat storage capacity of the filling body with 20 % PCM increases from 56.64 × 10⁶ kJ to 85.27 × 10⁶ kJ，and the heat release capacity increases from 48.54 × 10⁶ kJ to 68.2 × 10⁶ kJ ,with an increase of 50.5 % and 40.5 % respectively.

The results of this study provide a theoretical reference for the utilization of underground space and seasonal heat storage, and provide basic data for the selection of heat transfer parameters in seasonal heat storage of filling body.

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