增强型地热系统（Enhanced Geothermal System, EGS）作为未来新能源和清洁能源利用的一个重要方向，受到了世界各国的广泛关注。一直以来，野外试验场的工程实践和数值模拟分析是进行EGS研究的两种主要方式。本文通过实验室规模的小型试验系统，对EGS的水力压裂、裂隙监测、生产井定位和注水测试进行了仿真，成功实现了注入井−热储层−生产井的水力连通，分别以定井口压力和定注水流量进行水力测试。试验结果表明，热储层的裂隙开度会随着水力特性而发生变化，注水压力较大时热储层的裂隙具有更大的开度和渗流能力。从提升热储层经济性的角度考虑，实践中应当在较大注水压力时对热储裂隙结构进行加固处理。%Enhanced geothermal system (EGS), as an important direction for new and clean energy development, is gaining increasing attentions across the world. Direct engineering practice research in field test site and theoretical analysis by numerical simulation are mainly two kinds of EGS research methods. We conducted laboratory-scale tests for EGS research. The hydraulic fracturing of rocks was performed and the fracture structures were identified by using the acoustic emission data. Valid heat reservoir of hydraulic connection from the injection well to the production well through the fractures is obtained after the installation of the production. Then we performed the injection tests in the heat reservoir at a constant pressure of constant flow rate. It is found that the fracture apertures of reservoir vary with the injection conditions. A higher pressure or a larger flow rate leads to larger fracture apertures. In order to enhance the reservoir permeability, the fractures in reservoir should be reinforced in higher pressure condition for which the reservoir permeability is relatively large.
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