考虑非线性流动特性的裂隙岩体传热模拟OA

A finite volume method is proposed for the thermo-hydro coupling in fractured rock masses,which accounts for the nonlinear flow behavior in fractures.Firstly,the finite volume discrete formulations of the Forchheimer flow and heat transfer equations were derived.Then,these formulations were assembled into a system of nonlinear algebraic equations via flux/heat transfer functions between the fracture medium and the rock matrix,which was then solved by direct iterative method.The reliability of the proposed method in simulating nonlinear flow was subsequently verified through an intersecting fracture model.Finally,taking the Habanero geothermal reservoir in Australia as an example,the geothermal production process under different injection pressures was simulated to analyze the heat extraction efficiency of the reservoir.The results indicate that high injection pressure reduces the production life of the reservoir,but with further increase of injection pressure,the production life decreases to a constant value.Furthermore,Forchheimer flow significantly increases flow resistance through nonlinear inertial effects,resulting in actual flow rates being lower than linear flow predictions at high injection pressures,and intensifies the preferential channeling effect of fluids in the main fractures.These findings provide references for the injection and production design of dry geothermal reservoirs.