Permeability is a vital property of rock mass, which is highly affected by tectonic stress and human engineering activities. A comprehensive monitoring of pore pressure and flow rate distributions inside the rock mass...Permeability is a vital property of rock mass, which is highly affected by tectonic stress and human engineering activities. A comprehensive monitoring of pore pressure and flow rate distributions inside the rock mass is very important to elucidate the permeability evolution mechanisms, which is difficult to realize in laboratory, but easy to be achieved in numerical simulations. Therefore, the particle flow code (PFC), a discrete element method, is used to simulate permeability behaviors of rock materials in this study. Owe to the limitation of the existed solid-fluid coupling algorithm in PFC, an improved flow-coupling algorithm is presented to better reflect the preferential flow in rock fractures. The comparative analysis is conducted between original and improved algorithm when simulating rock permeability evolution during triaxial compression, showing that the improved algorithm can better describe the experimental phenomenon. Furthermore, the evolution of pore pressure and flow rate distribution during the flow process are analyzed by using the improved algorithm. It is concluded that during the steady flow process in the fractured specimen, the pore pressure and flow rate both prefer transmitting through the fractures rather than rock matrix. Based on the results, fractures are divided into the following three types: I) fractures link to both the inlet and outlet, II) fractures only link to the inlet, and III) fractures only link to the outlet. The type I fracture is always the preferential propagating path for both the pore pressure and flow rate. For type II fractures, the pore pressure increases and then becomes steady. However, the flow rate increases first and begins to decrease after the flow reaches the stop end of the fracture and finally vanishes. There is no obvious pore pressure or flow rate concentration within type III fractures.展开更多
This study examines the intricate occurrences of thermal and solutal Marangoni convection in three-layered flows of viscous fluids,with a particular emphasis on their relevance to renewable energy systems.This researc...This study examines the intricate occurrences of thermal and solutal Marangoni convection in three-layered flows of viscous fluids,with a particular emphasis on their relevance to renewable energy systems.This research examines the flow of a three-layered viscous fluid,considering the combined influence of heat and solutal buoyancy driven Rayleigh-Bénard convection,as well as thermal and solutal Marangoni convection.The homotopy perturbation method is used to examine and simulate complex fluid flow and transport phenomena,providing important understanding of the fundamental physics and assisting in the optimization of various battery configurations.The inquiry examines the primary elements that influence Marangoni convection and its impact on battery performance,providing insights on possible enhancements in energy storage devices.The findings indicate that the velocity profiles shown graphically exhibit a prominent core zone characterized by the maximum speed,which progressively decreases as it approaches the walls of the channel.This study enhances our comprehension of fluid dynamics and the transmission of heat and mass in intricate systems,which has substantial ramifications for the advancement of sustainable energy solutions.展开更多
基金Project(BK20150005) supported by the Natural Science Foundation of Jiangsu Province for Distinguished Young Scholars, China Project(2015XKZD05) supported by the Fundamental Research Funds for the Central Universities, China
文摘Permeability is a vital property of rock mass, which is highly affected by tectonic stress and human engineering activities. A comprehensive monitoring of pore pressure and flow rate distributions inside the rock mass is very important to elucidate the permeability evolution mechanisms, which is difficult to realize in laboratory, but easy to be achieved in numerical simulations. Therefore, the particle flow code (PFC), a discrete element method, is used to simulate permeability behaviors of rock materials in this study. Owe to the limitation of the existed solid-fluid coupling algorithm in PFC, an improved flow-coupling algorithm is presented to better reflect the preferential flow in rock fractures. The comparative analysis is conducted between original and improved algorithm when simulating rock permeability evolution during triaxial compression, showing that the improved algorithm can better describe the experimental phenomenon. Furthermore, the evolution of pore pressure and flow rate distribution during the flow process are analyzed by using the improved algorithm. It is concluded that during the steady flow process in the fractured specimen, the pore pressure and flow rate both prefer transmitting through the fractures rather than rock matrix. Based on the results, fractures are divided into the following three types: I) fractures link to both the inlet and outlet, II) fractures only link to the inlet, and III) fractures only link to the outlet. The type I fracture is always the preferential propagating path for both the pore pressure and flow rate. For type II fractures, the pore pressure increases and then becomes steady. However, the flow rate increases first and begins to decrease after the flow reaches the stop end of the fracture and finally vanishes. There is no obvious pore pressure or flow rate concentration within type III fractures.
基金Project(52276068)supported by the National Natural Science Foundation of China。
文摘This study examines the intricate occurrences of thermal and solutal Marangoni convection in three-layered flows of viscous fluids,with a particular emphasis on their relevance to renewable energy systems.This research examines the flow of a three-layered viscous fluid,considering the combined influence of heat and solutal buoyancy driven Rayleigh-Bénard convection,as well as thermal and solutal Marangoni convection.The homotopy perturbation method is used to examine and simulate complex fluid flow and transport phenomena,providing important understanding of the fundamental physics and assisting in the optimization of various battery configurations.The inquiry examines the primary elements that influence Marangoni convection and its impact on battery performance,providing insights on possible enhancements in energy storage devices.The findings indicate that the velocity profiles shown graphically exhibit a prominent core zone characterized by the maximum speed,which progressively decreases as it approaches the walls of the channel.This study enhances our comprehension of fluid dynamics and the transmission of heat and mass in intricate systems,which has substantial ramifications for the advancement of sustainable energy solutions.