Study On The Mechanism Of Liquid-solid Two-phase Coupling Of Carbonate Rock Fractures

In recent years, the proportion of new proven complex fractured oil and gas reservoirs has increased in total proven reserves of oil and gas resources, However, due to the fractured reservoirs generally buried deep, the safe density window is narrow, the wellbore pressure and large fluctuation in the process of drilling, are often faced with spills with the deposits, well control risks and other issues. Based on the crack characteristic parameters to measurement and reconstruction cracks in 3D space, and to carry out the research of cracks Dynamic Deformation Characteristics is the basis of the aforementioned problems and to further develops related engineering and technology research. Comprehensive utilization of fine surface shape measurement, three-dimensional reconstruction, rock mechanics, multiple physical field coupling simulation experiment and theory method, the single fracture space fine measurement, modeling and mathematical reconfiguration, dynamic simulation and experimental study on crack closure was achieved as follows:(1)Through using shining 3D non-contact precision measurement systems, to research natural fracture surface of three-dimensional surface features, asperity distribution laws and the surface shape parameters of cracks, reconstruction of the surface of cracks and three-dimensional space model;(2)To carry out the finite element simulation of the contact deformation and plastic flow region and the stress distribution law;Through reverse engineering modeling and simulation method of combining the study of stress and strain in the process of dynamic fracture closure law, study verified the fracture closure three stages of the stress distribution and change laws of velocity field, pressure field;(3)Based on real crack space, the influence factors of seepage simulation real fracture roughness and fracture width influence on seepage, it is concluded that the flow field in the real crack distribution;(4)Adopt parallel coupling computation method, fracture space is studied under the condition of fluctuating pressure, cracks within the general regulation of solid phased particles migration settlement, to reveal the drilling condition under the dynamic change of fracture space change when fluid coupling characteristics of solid phased particles also, formation fluid solid coupling wellbore flow and reservoir analysis while drilling, reservoir protection and lost circulation while drilling, and other fields of provides the theory basis for further research.,...