A coupling model is proposed in this paper by using the Green Function and Newman＇s product principle, and the solution method is provided here as well. This model can be used to describe the reservoir inflow and wel...A coupling model is proposed in this paper by using the Green Function and Newman＇s product principle, and the solution method is provided here as well. This model can be used to describe the reservoir inflow and wellbore flow for fishbone wells in an unsteady flow or pseudo-steady flow state. A case study indicates that the bottom hole pressure declines quickly in the unsteady flow period which is very short. The pressure drop per unit time remains unchanged under the pseudo-steady flow conditions. The distribution of flow rate along the main wellbore shows a wave shape under the unsteady flow condition, and the flow rate distribution in each branch is similar. The flow rate distribution along the main wellbore is irregular ＂U＂ shaped under the pseudo-steady flow condition, and the space-symmetrical branches have the same flow distribution pattern. In the initial production period, the flow rate increases significantly as the length of branches and the angle between branches and the main wellbore increase. As the production continues, the length and angle of branches have only a slight effect on the flow in fishbone wells.展开更多
The temperature field distribution and thermal history of Fe-9Cr2WVTa reduced activation steel prepared by laser melting deposition(LMD)have been calculated with Gaussian and Ring laser beams,and the nucleation and gr...The temperature field distribution and thermal history of Fe-9Cr2WVTa reduced activation steel prepared by laser melting deposition(LMD)have been calculated with Gaussian and Ring laser beams,and the nucleation and growth behaviors of M_(23)C_(6)precipitates in the 1st,7th and 19th layers have been calculated using the modified classical nucleation theory and Svoboda Fischer Fratzl Kozeschnik model.The energy distribution shows W-shape with Ring laser beam while it shows V-shape with Gaussian laser beam,which results in the more uniform M_(23)C_(6)size in the same layer with Ring laser beam.Precipitates in the bottom(i.e.,the 1st layer)have the minimum size and the size increases with the layer number with Gaussian and Ring laser beams.The temperature history,the instantaneous nucleation rate and the size evolution of M_(23)C_(6)have been systematically discussed.The results indicate that the nucleation,growth and re-dissolution of precipitates in reduced activation steel depend on the amount of energy absorbed in the thermal cycle during LMD.The continuous accumulation of energy during the thermal cycle leads to larger M_(23)C_(6)at the top area.The unsteady state precipitation dynamics of M_(23)C_(6)carbides during thermal cycling are consistent with the simulation results.展开更多
基金support from the National Science and Technology Major Projects of China(Grant No. 2011ZX05031-003)
文摘A coupling model is proposed in this paper by using the Green Function and Newman＇s product principle, and the solution method is provided here as well. This model can be used to describe the reservoir inflow and wellbore flow for fishbone wells in an unsteady flow or pseudo-steady flow state. A case study indicates that the bottom hole pressure declines quickly in the unsteady flow period which is very short. The pressure drop per unit time remains unchanged under the pseudo-steady flow conditions. The distribution of flow rate along the main wellbore shows a wave shape under the unsteady flow condition, and the flow rate distribution in each branch is similar. The flow rate distribution along the main wellbore is irregular ＂U＂ shaped under the pseudo-steady flow condition, and the space-symmetrical branches have the same flow distribution pattern. In the initial production period, the flow rate increases significantly as the length of branches and the angle between branches and the main wellbore increase. As the production continues, the length and angle of branches have only a slight effect on the flow in fishbone wells.
基金This work is supported by NSAF(Grant No.U2030102)National Natural Science Foundation of China(Grant Nos.52071124 and 51701134)State Key Laboratory of New Ceramic and Fine Processing,Tsinghua University(No.KF202115).
文摘The temperature field distribution and thermal history of Fe-9Cr2WVTa reduced activation steel prepared by laser melting deposition(LMD)have been calculated with Gaussian and Ring laser beams,and the nucleation and growth behaviors of M_(23)C_(6)precipitates in the 1st,7th and 19th layers have been calculated using the modified classical nucleation theory and Svoboda Fischer Fratzl Kozeschnik model.The energy distribution shows W-shape with Ring laser beam while it shows V-shape with Gaussian laser beam,which results in the more uniform M_(23)C_(6)size in the same layer with Ring laser beam.Precipitates in the bottom(i.e.,the 1st layer)have the minimum size and the size increases with the layer number with Gaussian and Ring laser beams.The temperature history,the instantaneous nucleation rate and the size evolution of M_(23)C_(6)have been systematically discussed.The results indicate that the nucleation,growth and re-dissolution of precipitates in reduced activation steel depend on the amount of energy absorbed in the thermal cycle during LMD.The continuous accumulation of energy during the thermal cycle leads to larger M_(23)C_(6)at the top area.The unsteady state precipitation dynamics of M_(23)C_(6)carbides during thermal cycling are consistent with the simulation results.
