It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. Th...It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. The impacts of well conditions including temperature, pressure and shear rate, on the crude oil rheology were comprehensively investigated and correlated using several empirical rheological models. The experimental data indicate that this heavy oil is very sensitive to temperature as result of microstructure change caused by hydrogen bonding. The rheological behavior of the heavy oil is also significantly impacted by the imposed pressure, i.e., the viscosity flow activation energy(Eμ) gently increases with the increasing pressure. The viscosity–shear rate data are well fitted to the power law model at low temperature. However, due to the transition of fluid feature at high temperature(Newtonian fluid), the measured viscosity was found to slightly deviate from the fitting data. Combining the evaluated correlations, the viscosity profile of the heavy crude oil in these two deep artesian wells as a function of well depth was predicted using the oilfield producing data.展开更多
The effect of β→α cooling rate during quenching on a new Zr-Sn-Nb-Fe-Cr-Cu alloy is reported.The microstructure evolution is well characterized by electron channeling contrast(ECC) imaging and transmission electron...The effect of β→α cooling rate during quenching on a new Zr-Sn-Nb-Fe-Cr-Cu alloy is reported.The microstructure evolution is well characterized by electron channeling contrast(ECC) imaging and transmission electron microscopy(TEM) techniques.The results show that specimens cooled by water,liquid nitrogen,air and furnace from β-phase present martensitic,coarse basket-weave,parallel-plate and lenticular structure,respectively.Residual β phase is detected by performing electron diffraction and composition analysis in the furnace cooled specimen.Micro hardness values of specimens decrease while the width of α laths increase with the cooling rate decreasing.The preliminarily established quantitative relationship among the cooling rate,microstructure and mechanical properties will shed light on the microstructure control and property optimization.展开更多
基金Supported by the National Key Science&Technology Projects during 13th Five-Year Plan(2016ZX05053-003)Young Scholars Development fund of SWPU(201499010121)
文摘It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. The impacts of well conditions including temperature, pressure and shear rate, on the crude oil rheology were comprehensively investigated and correlated using several empirical rheological models. The experimental data indicate that this heavy oil is very sensitive to temperature as result of microstructure change caused by hydrogen bonding. The rheological behavior of the heavy oil is also significantly impacted by the imposed pressure, i.e., the viscosity flow activation energy(Eμ) gently increases with the increasing pressure. The viscosity–shear rate data are well fitted to the power law model at low temperature. However, due to the transition of fluid feature at high temperature(Newtonian fluid), the measured viscosity was found to slightly deviate from the fitting data. Combining the evaluated correlations, the viscosity profile of the heavy crude oil in these two deep artesian wells as a function of well depth was predicted using the oilfield producing data.
基金supported by the programs of New Century Excellent Talents in University (Grant No.NCET-08-0606)the Sharing Fund of Chongqing University's Large-scale Equipmentthe Fundamental Research Funds for the Central Universities of China (Grant Nos. CDJZR10130008 and CDJXS10132201)
文摘The effect of β→α cooling rate during quenching on a new Zr-Sn-Nb-Fe-Cr-Cu alloy is reported.The microstructure evolution is well characterized by electron channeling contrast(ECC) imaging and transmission electron microscopy(TEM) techniques.The results show that specimens cooled by water,liquid nitrogen,air and furnace from β-phase present martensitic,coarse basket-weave,parallel-plate and lenticular structure,respectively.Residual β phase is detected by performing electron diffraction and composition analysis in the furnace cooled specimen.Micro hardness values of specimens decrease while the width of α laths increase with the cooling rate decreasing.The preliminarily established quantitative relationship among the cooling rate,microstructure and mechanical properties will shed light on the microstructure control and property optimization.
