干热岩人工裂隙三维流动传热的数值模拟研究.

The flow and heat transfer models of hot dry rock are mainly based on the assumption of two-dimensional model, which cannot fully reflect the physical process of three-dimensional flow and heat transfer in artificial fractures. The three-dimensional flow heat transfer numerical model of a single fracture was established by ANSYS Fluent, and the relevant numerical simulation calculation was carried out. The influence of different factors on the fluid temperature in the fracture of hot dry rock was analyzed, and the heat transfer rules of the fluid in the fracture under different conditions were obtained. Numerical simulation results show that the main factors affecting the heat transfer of hot dry rock fractures include: the injection rate of working fluid, fracture width, fracture length and initial fluid temperature. Under the conditions of a given fracture length and inflow velocity, the smaller the width of the artificial fracture, the higher the temperature of the fluid flowing out of the outlet, the longer the length of the fracture which the fluid flows through, and the greater the temperature increase. With the same fracture width and length, the smaller the flow rate, the higher the temperature at the fluid outlet, the slower the flow rate, the longer the heat exchange time, and the more heat is transferred. For different frac ture widths and different inflow speeds, after the fracture length reaches a certain level, the water temperature can be increased to be consistent with the bedrock. [ABSTRACT FROM AUTHOR]