Chemical flooding is one of the effective technologies to increase oil recovery of petroleum reservoirs after water flooding.Above the scale of representative elementary volume(REV), phenomenological modeling and nume...Chemical flooding is one of the effective technologies to increase oil recovery of petroleum reservoirs after water flooding.Above the scale of representative elementary volume(REV), phenomenological modeling and numerical simulations of chemical flooding have been reported in literatures,but the studies alike are rarely conducted at the pore-scale,at which the effects of physicochemical hydrodynamics are hardly resolved either by experimental observations or by traditional continuum-based simulations.In this paper,dissipative particle dynamics(DPD),one of mesoscopic fluid particle methods,is introduced to simulate the pore-scale flow in chemical flooding processes.The theoretical background,mathematical formulation and numerical approach of DPD are presented.The plane Poiseuille flow is used to illustrate the accuracy of the DPD simulation,and then the processes of polymer flooding through an oil-wet throat and a water-wet throat are studies, respectively.The selected parameters of those simulations are given in details.These preliminary results show the potential of this novel method for modeling the physicochemical hydrodynamics at the pore scale in the area of chemical enhanced oil recovery.展开更多
The mechanics and swelling kinetics of polymeric microgels are simulated using a mesoscale computational model based on dissipative particle dynamics. Microgels are represented by a random elastic network submerged in...The mechanics and swelling kinetics of polymeric microgels are simulated using a mesoscale computational model based on dissipative particle dynamics. Microgels are represented by a random elastic network submerged in an explicit viscous solvent. The model is used to probe the effect of different solvent conditions on the bulk modulus of the microgels. Comparison of the simulation results through the volume phase transition reveals favorable agreement with Flory-Rehner＇s theory for polymeric gels. The model is also used to examine the microgel swelling kinetics, and is found to be in good agreement with Tanaka＇s theory for spherical gels. The simulations show that, during the swelling process, the microgel maintains a nearly homogeneous structure, whereas deswelling is characterized by the formation of chain bundles and network coarsening.展开更多
This study presents the interaction between konjac glucanmannan（KGM） and cationic surfactant dodecyl trimethylammonium chloride（DTAC） to provide theoretical guidance and prediction for the experimental design and ...This study presents the interaction between konjac glucanmannan（KGM） and cationic surfactant dodecyl trimethylammonium chloride（DTAC） to provide theoretical guidance and prediction for the experimental design and application of this composite system. Dissipative particle dynamics（DPD） method was used to simulate the interaction between KGM and the cationic surfactant. Influences of concentration, temperature and shear process on the structure and properties of aggregates were mainly examined. The results revealed that the density peak increased with the increase of concentration of KGM. With increasing the temperature, density peak moved to the right and increased, and then decreased when the temperature rose to a certain value. The density peak moved to the right at the low shear rate while decreased at the high one. During simulation, the high viscosity related to the low diffusion rate, which made it difficult to form a large continuous phase.展开更多
The aggregates in sodium dedecylsulphate (SDS)/dimethylbenzene/water systems have been investigated using dissipative particles dynamic (DPD) simulation method. Through analyzing three dimensional structures of aggre...The aggregates in sodium dedecylsulphate (SDS)/dimethylbenzene/water systems have been investigated using dissipative particles dynamic (DPD) simulation method. Through analyzing three dimensional structures of aggregates, three simulated results are found. One is the phase separation, which is clearly observed by water density and the aggregates in the simulated cell; another is the water morphology in reverse micelle, which can be found through the isodensity slice of water including bound water, trapped water and bulky water; the third is about the water/oil interface, i.e., ionic surfactant molecules, SDS, prefer to exist in the interface between water and oil phase at the low concentration.展开更多
基金supported by the National Basic Research Program of China(2005CB221307 & 2005CB221304)China Postdoctoral Science Foundation(20090460391 & 201003138)PetroChina RIPED Innovations Foundation.
文摘Chemical flooding is one of the effective technologies to increase oil recovery of petroleum reservoirs after water flooding.Above the scale of representative elementary volume(REV), phenomenological modeling and numerical simulations of chemical flooding have been reported in literatures,but the studies alike are rarely conducted at the pore-scale,at which the effects of physicochemical hydrodynamics are hardly resolved either by experimental observations or by traditional continuum-based simulations.In this paper,dissipative particle dynamics(DPD),one of mesoscopic fluid particle methods,is introduced to simulate the pore-scale flow in chemical flooding processes.The theoretical background,mathematical formulation and numerical approach of DPD are presented.The plane Poiseuille flow is used to illustrate the accuracy of the DPD simulation,and then the processes of polymer flooding through an oil-wet throat and a water-wet throat are studies, respectively.The selected parameters of those simulations are given in details.These preliminary results show the potential of this novel method for modeling the physicochemical hydrodynamics at the pore scale in the area of chemical enhanced oil recovery.
基金Project supported by the National Science Foundation of U.S.A.(Nos.DMR-1255288,DMR-1609841,and DGE-1650044)
文摘The mechanics and swelling kinetics of polymeric microgels are simulated using a mesoscale computational model based on dissipative particle dynamics. Microgels are represented by a random elastic network submerged in an explicit viscous solvent. The model is used to probe the effect of different solvent conditions on the bulk modulus of the microgels. Comparison of the simulation results through the volume phase transition reveals favorable agreement with Flory-Rehner＇s theory for polymeric gels. The model is also used to examine the microgel swelling kinetics, and is found to be in good agreement with Tanaka＇s theory for spherical gels. The simulations show that, during the swelling process, the microgel maintains a nearly homogeneous structure, whereas deswelling is characterized by the formation of chain bundles and network coarsening.
基金supported by the National Natural Science Foundation of China(31471704 and 31271837)
文摘This study presents the interaction between konjac glucanmannan（KGM） and cationic surfactant dodecyl trimethylammonium chloride（DTAC） to provide theoretical guidance and prediction for the experimental design and application of this composite system. Dissipative particle dynamics（DPD） method was used to simulate the interaction between KGM and the cationic surfactant. Influences of concentration, temperature and shear process on the structure and properties of aggregates were mainly examined. The results revealed that the density peak increased with the increase of concentration of KGM. With increasing the temperature, density peak moved to the right and increased, and then decreased when the temperature rose to a certain value. The density peak moved to the right at the low shear rate while decreased at the high one. During simulation, the high viscosity related to the low diffusion rate, which made it difficult to form a large continuous phase.
基金ProjectsupportedbytheNaturalScienceFoundationofShandongProvince (No .Y2 0 0 1B0 8)
文摘The aggregates in sodium dedecylsulphate (SDS)/dimethylbenzene/water systems have been investigated using dissipative particles dynamic (DPD) simulation method. Through analyzing three dimensional structures of aggregates, three simulated results are found. One is the phase separation, which is clearly observed by water density and the aggregates in the simulated cell; another is the water morphology in reverse micelle, which can be found through the isodensity slice of water including bound water, trapped water and bulky water; the third is about the water/oil interface, i.e., ionic surfactant molecules, SDS, prefer to exist in the interface between water and oil phase at the low concentration.
