As a natural and environmentally friendly renewable material,Northeast China ash wood(NCAW)(Fraxinus mandshurica Rupr.)was cut by water-jet assisted CO_(2) laser(WACL),the surface quality was evaluated by surface roug...As a natural and environmentally friendly renewable material,Northeast China ash wood(NCAW)(Fraxinus mandshurica Rupr.)was cut by water-jet assisted CO_(2) laser(WACL),the surface quality was evaluated by surface roughness of cut section.The surface roughness was measured by three-dimensional(3D)profilometry.Furthermore,the micromorphology of machined surface was observed by scanning electronic microscopy(SEM).Carbon content changes of machined surface were measured by energy dispersive spectrometer(EDS).A relationship between surface roughness and cutting parameters was established using response surface methodology(RSM).It is concluded that the cutting speed,laser power and water pressure played an important role in surface roughness of cut section.The surface roughness increased as an increase in laser power.It decreased caused by increasing of cutting speed and water pressure.Measurements revealed that the surface quality of NCAW part was improved using the optimized combination of cutting parameters.The established quadratic mathematical model of a good prediction is helpful for matching suitable cutting parameters to obtain expected surface quality.展开更多
To improve the oil recovery and economic efficiency in heavy oil reservoirs in late steam flooding,taking J6 Block of Xinjiang Oilfield as the research object,3D physical modeling experiments of steam flooding,CO2-foa...To improve the oil recovery and economic efficiency in heavy oil reservoirs in late steam flooding,taking J6 Block of Xinjiang Oilfield as the research object,3D physical modeling experiments of steam flooding,CO2-foam assisted steam flooding,and CO2 assisted steam flooding under different perforation conditions are conducted,and CO2-assisted steam flooding is proposed for reservoirs in the late stage of steam flooding.The experimental results show that after adjusting the perforation in late steam flooding,the CO2 assisted steam flooding formed a lateral expansion of the steam chamber in the middle and lower parts of the injection well and a development mode for the production of overriding gravity oil drainage in the top chamber of the production well;high temperature water,oil,and CO2 formed stable low-viscosity quasi-single-phase emulsified fluid;and CO2 acted as a thermal insulation in the steam chamber at the top,reduced the steam partial pressure inside the steam chamber,and effectively improved the heat efficiency of injected steam.Based on the three-dimensional physical experiments and the developed situation of the J6 block in Xinjiang Oilfield,the CO2 assisted steam flooding for the J6 block was designed.The application showed that the CO2 assisted steam flooding made the oil vapor ratio increase from 0.12 to 0.16 by 34.0%,the oil recovery increase from 16.1%to 21.5%,and the final oil recovery goes up to 66.5%compared to steam flooding after perforation adjustment.展开更多
基金This research was supported by the Applied Technology Research and Development Project in Heilongjiang Province of China(GA19A402)Fundamental Research Funds for the Central Universities(2572018CG06).
文摘As a natural and environmentally friendly renewable material,Northeast China ash wood(NCAW)(Fraxinus mandshurica Rupr.)was cut by water-jet assisted CO_(2) laser(WACL),the surface quality was evaluated by surface roughness of cut section.The surface roughness was measured by three-dimensional(3D)profilometry.Furthermore,the micromorphology of machined surface was observed by scanning electronic microscopy(SEM).Carbon content changes of machined surface were measured by energy dispersive spectrometer(EDS).A relationship between surface roughness and cutting parameters was established using response surface methodology(RSM).It is concluded that the cutting speed,laser power and water pressure played an important role in surface roughness of cut section.The surface roughness increased as an increase in laser power.It decreased caused by increasing of cutting speed and water pressure.Measurements revealed that the surface quality of NCAW part was improved using the optimized combination of cutting parameters.The established quadratic mathematical model of a good prediction is helpful for matching suitable cutting parameters to obtain expected surface quality.
基金Supported by the China National Science and Technology Major Project(2016ZX05012-002).
文摘To improve the oil recovery and economic efficiency in heavy oil reservoirs in late steam flooding,taking J6 Block of Xinjiang Oilfield as the research object,3D physical modeling experiments of steam flooding,CO2-foam assisted steam flooding,and CO2 assisted steam flooding under different perforation conditions are conducted,and CO2-assisted steam flooding is proposed for reservoirs in the late stage of steam flooding.The experimental results show that after adjusting the perforation in late steam flooding,the CO2 assisted steam flooding formed a lateral expansion of the steam chamber in the middle and lower parts of the injection well and a development mode for the production of overriding gravity oil drainage in the top chamber of the production well;high temperature water,oil,and CO2 formed stable low-viscosity quasi-single-phase emulsified fluid;and CO2 acted as a thermal insulation in the steam chamber at the top,reduced the steam partial pressure inside the steam chamber,and effectively improved the heat efficiency of injected steam.Based on the three-dimensional physical experiments and the developed situation of the J6 block in Xinjiang Oilfield,the CO2 assisted steam flooding for the J6 block was designed.The application showed that the CO2 assisted steam flooding made the oil vapor ratio increase from 0.12 to 0.16 by 34.0%,the oil recovery increase from 16.1%to 21.5%,and the final oil recovery goes up to 66.5%compared to steam flooding after perforation adjustment.
