In this work, we performed the pulse-decay experiment on a fractured shale core and applied the 3 D embedded discrete fracture model(EDFM) to simulate the experiment process. The irregularly rough fracture surface was...In this work, we performed the pulse-decay experiment on a fractured shale core and applied the 3 D embedded discrete fracture model(EDFM) to simulate the experiment process. The irregularly rough fracture surface was depicted in detail using a 3 D scanner. Then the fracture surface profile was imported in the discrete fracture network model to simulate the flow process in the fracture-matrix system realistically. History matching was efficiently performed to simultaneously obtain porosity and permeability for the matrix and fracture. Gas properties after applying nanopore confinement were obtained by modifying Sutton's viscosity correlation with sensitivity analysis on the pore diameter ranging from 2 to50 nm. Nanopore confinement results in low matched permeability due to viscosity reduction in the matrix-only porous media. The fracture-matrix system complicates the interpretation of nanopore confinement impact on flow behavior in shale reservoirs. Different scenarios of the highly fractured and matrix-dominated systems were discussed in detail by constructing the digital twin model.展开更多
A good model can extract useful information about the target's state from observations effectively. There are many models used to tracking a, maneuvering target such as constant-velocity (CV) model, Singer accelera...A good model can extract useful information about the target's state from observations effectively. There are many models used to tracking a, maneuvering target such as constant-velocity (CV) model, Singer acceleration model (zero-mean first-order Markov model) and current model (mean-adaptive acceleration model), etc. While due to the complexity of maneuvering target, to seek the target model which can get better performance is still a subject worthy of study. Based on statistics relation between the autocormlation function and the covariance of Markov random processing, this paper develops a model which can adaptively adjust system parameters on line. Simulations show the good estimation performance get by the model developed here, and comparing CV, Singer and current models, the model can adaptively get the model parameter while tracking the trajectory and needn't doing several tests to obtain a priori parameter.展开更多
基金supported by the Science Foundation of China University of Petroleum,Beijing (No.00000)the Strategic Cooperation Technology Projects of CNPC and CUPB (ZLZX2020-01)CNPC Science and Technology Major Project (2021ZZ10-02)。
文摘In this work, we performed the pulse-decay experiment on a fractured shale core and applied the 3 D embedded discrete fracture model(EDFM) to simulate the experiment process. The irregularly rough fracture surface was depicted in detail using a 3 D scanner. Then the fracture surface profile was imported in the discrete fracture network model to simulate the flow process in the fracture-matrix system realistically. History matching was efficiently performed to simultaneously obtain porosity and permeability for the matrix and fracture. Gas properties after applying nanopore confinement were obtained by modifying Sutton's viscosity correlation with sensitivity analysis on the pore diameter ranging from 2 to50 nm. Nanopore confinement results in low matched permeability due to viscosity reduction in the matrix-only porous media. The fracture-matrix system complicates the interpretation of nanopore confinement impact on flow behavior in shale reservoirs. Different scenarios of the highly fractured and matrix-dominated systems were discussed in detail by constructing the digital twin model.
基金supported by the National Natural Science Foundation of China (61273002, 60971119)
文摘A good model can extract useful information about the target's state from observations effectively. There are many models used to tracking a, maneuvering target such as constant-velocity (CV) model, Singer acceleration model (zero-mean first-order Markov model) and current model (mean-adaptive acceleration model), etc. While due to the complexity of maneuvering target, to seek the target model which can get better performance is still a subject worthy of study. Based on statistics relation between the autocormlation function and the covariance of Markov random processing, this paper develops a model which can adaptively adjust system parameters on line. Simulations show the good estimation performance get by the model developed here, and comparing CV, Singer and current models, the model can adaptively get the model parameter while tracking the trajectory and needn't doing several tests to obtain a priori parameter.