随着浅层矿产资源逐渐枯竭开采深度在不断加深，面对更加突出的高井温问题，国内外一些研究机构提出矿床与地热协同开采模式，其中借助矿井已有井巷工程采用功能性充填技术构筑埋管充填体是实现地热开采的有效方式之一。在深部矿井高温度、高应力和高渗透压环境下，埋管充填体在长期周期性蓄/释热运行中必然会出现裂隙损伤，引起其传热性能变化，进而对地热开采效能产生影响，但相关研究很少，它们之间的关联特性尚不清晰。因此，本文以裂隙损伤埋管充填体为研究对象，采用实验测试与数值模拟相结合的方法，针对裂隙对埋管充填体蓄/释热性能的影响规律开展具体研究。
建立了埋管-充填体-裂隙的多场耦合三维数学模型，同时设计搭建了损伤埋管充填体蓄/释热实验台，验证了无渗流条件下数值模型的准确性；采用干热岩文献中裂隙渗流数据验证了本文裂隙渗流模型的准确性，给出了埋管充填体性能的评价指标。基于FLUENT模拟软件，研究了在无渗流条件下特殊单裂隙在不同边界条件下对实验尺寸损伤埋管充填体蓄/释热性能的影响，在此基础上进一步分析研究了多条平行裂隙在有/无渗流条件下对实际尺寸损伤埋管充填体蓄/释热过程中的温度场、蓄/释热量、埋管出口水温以及效率等参数影响规律。
首先研究了实验尺寸损伤埋管充填体在不同边界条件下，裂隙的开裂程度、位置和宽度对埋管充填体蓄/释热过程的影响。结果显示：以无损伤埋管充填体为基准，单侧加热情况下，裂隙完全开裂、位置在X=2cm处、宽度10mm时，埋管充填体的蓄热量和释热量最少，分别降低了63.21%和70.59%，平均换热效率降低了41.25%；对相同受损程度的埋管充填体，双侧加热相比单侧加热，蓄热量与释热量最多可提升3.22倍与3.67倍，但相比无损伤充填体，蓄热量和释热量分别降低了16.07%和29.58%，平均换热效率降低了15.16%。接着研究了实际尺寸损伤埋管充填体在裂隙内部有/无渗流条件下，裂隙数量、间距对损伤埋管充填体蓄/释热性能的影响。无渗流条件时，随着裂隙数量增大，裂隙间距减小，损伤埋管充填体蓄/释热量越少，裂隙数量N=7条，裂隙间距L=10cm的损伤埋管充填体蓄热8个月，释热4个月，蓄热量与释热量分别降低了11.09%与10.04%，仅相当于无损伤充填体蓄热6.2个月，释热1.7个月；有渗流则提升了损伤埋管充填体的蓄/释热性能，裂隙数量越多，裂隙间距越大，损伤埋管充填体蓄/释热量越多，裂隙数量N=7条，裂隙间距L=200cm的蓄热量和释热量分别上升了153.53%和138.65%，仅需5天即可达到无损伤充填体8个月的蓄热量，而释热4个月仍高于无损伤充填体蓄热8个月的温度。
本论文的研究结果为后期进一步开展不规则裂隙网群对损伤充填体蓄/释热性能的影响奠定了基础，为埋管充填体长期运行后的蓄/释热性能变化给出先行判断依据，对深部矿井地热资源的合理高效开采有一定的指导意义。

With the gradual depletion of shallow mineral resources mining depth in the deepening, the face of the more prominent high well temperature problem, facing the more prominent problem of high well temperature, some domestic and foreign research institutions propose a synergistic mining model of mineral deposits and geothermal, one of the effective ways to achieve geothermal mining is to use functional filling technology to construct buried pipe backfill with the help of existing shaft works in the mine. Under high temperature, high stress and high osmotic pressure environment in deep mines, buried pipe backfill in long-term cyclic heat storage and release operation is bound to fracture damage, causes changes in its heat transfer performance，this in turn has an impact on the efficiency of geothermal extraction, however, there are few relevant studies, the nature of their association is unclear. Therefore, this paper takes the fracture damage buried pipe backfill as the research object, using a combination of experimental tests and numerical simulations, specific research on the effect of fractures on the heat storage and release properties of buried pipe backfill. 
A multi-field coupled 3D mathematical model of buried pipe - backfill - fracture was established, also designed and built a damage buried pipe backfill heat storage/release test bench, verified the accuracy of the numerical model under no seepage conditions; the accuracy of the fracture seepage model in this paper was verified by using fracture seepage data from the dry heat rock literature. The evaluation index of the performance of buried pipe backfill is given, based on FLUENT simulation software, the effect of a special single fracture on the thermal storage/release performance of an experimentally sized damaged buried pipe backfill under no seepage conditions was investigated, on this basis, the effect of multiple parallel fractures with/without seepage on the temperature field, heat storage/release, buried pipe outlet water temperature and efficiency in the process of heat storage/release in the buried pipe backfill with actual size damage was further analyzed and studied.
Firstly, the experimental size damage buried pipe backfill was studied under different boundary conditions, effect of cracking degree, location and width on heat storage/release processes in buried pipe backfill.  The results show: no damage to the buried pipe backfill as a benchmark, in case of single-side heating, when the fracture is completely cracked, positioned at X=2cm and width 10mm, minimal heat storage and heat release in buried pipe backfill, by 63.21% and 70.59%, respectively, average heat transfer efficiency reduced by 41.25%; For the same degree of damage to the buried pipe backfill, double-side heating compared to single-side heating, up to 3.22 times more heat storage and 3.67 times more heat release, but compared to non-damaging backfill, the heat storage and heat release decreased by 16.07% and 29.58%, respectively, average heat transfer efficiency reduced by 15.16%. Then the actual size damage buried pipe backfill was investigated with/without seepage flow inside the fracture, effect of the number and spacing of fractures on the heat storage/release performance of buried pipe backfill, When there is no seepage condition,  as the number of fractures increases and the fractures spacing decreases, the less heat is stored/released from the damage buried pipe backfill, the damage buried tube backfill with the number of cracks N=7 and the distance between fractures L=10cm stored heat for 8 months and released heat for 4 months, the heat storage and heat release decreased by 11.09% and 10.04% respectively, which is only equivalent to 6.2 months of heat storage and 1.7 months of heat release for the undamaged backfill; The presence of seepage enhances the heat storage/release performance of the buried pipe backfill, the greater the number of fractures and the greater the fractures spacing, the more heat is stored/released from the damage buried pipe backfill, the number of fractures N=7 and the spacing between fractures L=200cm increased the heat storage and heat release by 153.53% and 138.65% respectively, and it only takes 5 days to reach the heat storage of the undamaged backfill for 8 months,  while the heat release for 4 months is still higher than the temperature of the undamaged backfill for 8 months.
The results of this thesis provide a basis for further work on the effect of irregular fracture network clusters on the heat storage/release properties of damaged backfill at a later stage, to provide a basis for judging the change of heat storage and release performance of buried pipe backfill after long-term operation, a guide to the rational and efficient exploitation of geothermal resources in deep mines.