基于随机相场模型的储气洞室起裂压力研究

Random Phase Field Model-based Research on Fracture Initiation Pressure of Gas Storage Caverns

摘要:

为研究围岩断裂力学参数的空间变异性对储气洞室起裂压力的影响，基于随机场理论、质量和能量守恒定律、傅里叶定律和变分一致原理建立适用于压气储能内衬洞室的热力耦合随机相场模型，并通过试验和数值模拟验证了其正确性。结合蒙特卡洛法，选取典型压气储能案例分析研究。研究表明：储气洞室的起裂压力受到岩体空间变异性的显著影响，随着弹性模量和临界能量释放率变异系数的增加而减小，且二者空间变异性共同作用下呈近似反比关系，而弹性模量和临界能量释放率的自相关距离的影响较小；弹性模量相较于临界能量释放率，其空间变异性对起裂压力的影响更大。

Abstract:

To investigate the impact of spatial variability of different mechanical parameters on the initial fracturing pressure of gas storage cavern. A thermomechanical coupling random phase field model， applicable to lined caverns for compressed air energy storage， was established based on the principles of random field theory， conservation laws of mass and energy， Fourier's law， and the variational principle. The correctness of the model was validated through experimental results and numerical simulation. Combining Monte Carlo method， a compressed air energy storage （CAES） case from literature was selected for analysis and study. The research indicates that the initiation pressure of a gas storage cavern is significantly influenced by the spatial variability of rock mass， decreasing with increasing coefficients of variation of the Young’s modulus and the critical energy release rate， and exhibiting an approximately inverse relationship under their combined variability. However， the autocorrelation distances of the Young’s modulus and critical energy release rate have a relatively minor impact. The spatial variability of Young’s modulus has a greater influence on the initiation pressure compared with the critical energy release rate.