Abstract: A fluid-solid coupling numerical simulation method for evaluating the effect of wellbore strengthening in a fractured formation includes steps of: establishing an elastic deformation equation of rocks around the wellbore; establishing and solving the fluid flow equations within fractures and plugging zone, respectively; substituting the discretized elastic deformation equation of the rocks around the borehole wall into the fluid flow equations of fractures to obtain a fluid-solid coupling equation set for wellbore strengthening in a fractured formation; and finally solving the fluid-solid coupling equation set; and substituting basic parameters into the fluid-solid coupling equation set, and simulating mechanical response characteristics, width evolution characteristics and flow distribution characteristics of plugged fractures under different parameter combinations.

Abstract: A method of designing a particle size distribution of particulate bridging lost circulation material for a fractured leakage includes the following steps: classifying the lost circulation materials according to a particle size; calculating an expected range of a characteristic particle size of the lost circulation materials according to a fracture width and particle size selection criteria; setting a relative percentage content of the each level of the lost circulation materials; using a particle size distribution function to fit a particle size distribution curve; calculating the characteristic particle size of the lost circulation materials according to the particle size distribution curve; determining whether the calculated characteristic particle size conforms to the expected range of the characteristic particle size; and generating the particle size distribution of the lost circulation materials conforming to the particle size selection criteria.

Abstract: A fluid-solid coupling numerical simulation method for evaluating the effect of wellbore strengthening in a fractured formation includes steps of: establishing an elastic deformation equation of rocks around the wellbore; establishing and solving the fluid flow equations within fractures and plugging zone, respectively; substituting the discretized elastic deformation equation of the rocks around the borehole wall into the fluid flow equations of fractures to obtain a fluid-solid coupling equation set for wellbore strengthening in a fractured formation; and finally solving the fluid-solid coupling equation set; and substituting basic parameters into the fluid-solid coupling equation set, and simulating mechanical response characteristics, width evolution characteristics and flow distribution characteristics of plugged fractures under different parameter combinations.

Abstract: The present disclosure provides systems and methods for determining in-situ stresses based on an orthotropic rock physics model. The method may include obtaining multiple physical parameters of a rock; constructing an orthotropic rock physics model based at least in part on the multiple physical parameters; determining multiple stiffness coefficients based on the orthotropic rock physics model; and determining one or more in-situ stresses of the orthotropic rock based on the multiple stiffness coefficients.

Abstract: A physical simulation and calibration device and method for formation pressure testing. The device has a rock core arranged in a rock core clamper, a confining pressure simulation module, formation pressure simulation module, annular pressure simulation module, suction system, thrust force simulation module and drive control system. The thrust force simulation module has a thrust rod which penetrates through a cavity wall on one side of the clamper. The front end of the thrust rod has a simulation probe. The suction system is connected to the thrust rod. The confining pressure simulation module, formation pressure simulation module, annular pressure simulation module, thrust force simulation module and suction system are all connected with the drive control system. The device and method simulate a physical environment of formation pressure testing to achieve physical simulation of formation pressure testing. A formation pressure tester can be corrected and calibrated.

Abstract: The present disclosure provides systems and methods for determining in-situ stresses based on an orthotropic rock physics model. The method may include obtaining multiple physical parameters of a rock; constructing an orthotropic rock physics model based at least in part on the multiple physical parameters; determining multiple stiffness coefficients based on the orthotropic rock physics model; and determining one or more in-situ stresses of the orthotropic rock based on the multiple stiffness coefficients.

Abstract: A method of designing a particle size distribution of particulate bridging lost circulation material for a fractured leakage includes the following steps: classifying the lost circulation materials according to a particle size; calculating an expected range of a characteristic particle size of the lost circulation materials according to a fracture width and particle size selection criteria; setting a relative percentage content of the each level of the lost circulation materials; using a particle size distribution function to fit a particle size distribution curve; calculating the characteristic particle size of the lost circulation materials according to the particle size distribution curve; determining whether the calculated characteristic particle size conforms to the expected range of the characteristic particle size; and generating the particle size distribution of the lost circulation materials conforming to the particle size selection criteria.

Abstract: A physical simulation and calibration device and method for formation pressure testing. The device has a rock core arranged in a rock core clamper, a confining pressure simulation module, formation pressure simulation module, annular pressure simulation module, suction system, thrust force simulation module and drive control system. The thrust force simulation module has a thrust rod which penetrates through a cavity wall on one side of the clamper. The front end of the thrust rod has a simulation probe. The suction system is connected to the thrust rod. The confining pressure simulation module, formation pressure simulation module, annular pressure simulation module, thrust force simulation module and suction system are all connected with the drive control system. The device and method simulate a physical environment of formation pressure testing to achieve physical simulation of formation pressure testing. A formation pressure tester can be corrected and calibrated.