In this paper, the method of aperture-field integral and GTD is used to calculate the radiationpatterns of choke horn. The influence of chokes' location was analyzed. The calculating results are inagreement with m...In this paper, the method of aperture-field integral and GTD is used to calculate the radiationpatterns of choke horn. The influence of chokes' location was analyzed. The calculating results are inagreement with measurement data. The method presented in this paper can be used to solve problems ofN chokes.展开更多
Based on the local resistance computation model for a choke valve and using the flow characteristics of choke valves, we studied the relationships between the back pressure of a parallel choke assembly and the opening...Based on the local resistance computation model for a choke valve and using the flow characteristics of choke valves, we studied the relationships between the back pressure of a parallel choke assembly and the opening extent of choke valves and developed a model to characterize the pressure regime of the manifold assembly. A comparison of pressure characteristic curves shows that a parallel choke manifold assembly has obvious advantages over the conventional serial type including high linearity of pressure-regulating characteristics curves, the elimination of the overshoot interval, wider effective regulating interval and the higher system security. Laboratory hydraulic experiments have validated the capability of a back pressure control model for the parallel choke assembly to accurately control pressure. This study is of great theoretical and practical significance to further improve the performance of chokes used in managed pressure well drilling.展开更多
Surface chokes are widely utilized equipment installed on wellheads to control hydrocarbon flow rates.Several correlations have been suggested to model the multiphase flow of oil and gas via surface chokes.However,sub...Surface chokes are widely utilized equipment installed on wellheads to control hydrocarbon flow rates.Several correlations have been suggested to model the multiphase flow of oil and gas via surface chokes.However,substantial errors have been reported in empirical fitting models and correlations to estimate hydrocarbon flow because of the reservoir's heterogeneity,anisotropism,variance in reservoir fluid characteristics at diverse subsurface depths,which introduces complexity in production data.Therefore,the estimation of daily oil and gas production rates is still challenging for the petroleum industry.Recently,hybrid data-driven techniques have been reported to be effective for estimation problems in various aspects of the petroleum domain.This paper investigates hybrid ensemble data-driven approaches to forecast multiphase flow rates through the surface choke(viz.stacked generalization and voting architectures),followed by an assessment of the impact of input production control variables.Otherwise,machine learning models are also trained and tested individually on the production data of hydrocarbon wells located in North Sea.Feature engineering has been properly applied to select the most suitable contributing control variables for daily production rate forecasting.This study provides a chronological explanation of the data analytics required for the interpretation of production data.The test results reveal the estimation performance of the stacked generalization architecture has outperformed other significant paradigms considered for production forecasting.展开更多
In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in ...In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in determining both the well’s initial production performance and its long-term hydrocarbon recovery.By establishing a comprehensive big data analysis platform,the flowback dynamics of over 1000 shale gas wells were analyzed in this work,leading to the development of an index system for evaluating flowback production capacity.Additionally,a shut-in chart was created for wells with different types of post-stimulation fracture networks,providing a structured approach to optimizing production strategies.A dynamic analysis method for flowback was also developed,using daily pressure drop and artificial fracture conductivity as key indicators.This method offers a systematic and effective approach to managing the shut-in and flowback processes for gas wells.Field trials demonstrated significant improvements:the probability of sand production was reduced,gas breakthrough time was extended,artificial fracture conductivity was enhanced,and the average estimated ultimate recovery(EUR)per well increased.展开更多
Charlie,a father from Sunderland,was enjoying a meal with friends when sudden panic erupted at a nearby table.A woman began to choke,her face turning red as her breaths became shallow.Her friend wildly pounded her bac...Charlie,a father from Sunderland,was enjoying a meal with friends when sudden panic erupted at a nearby table.A woman began to choke,her face turning red as her breaths became shallow.Her friend wildly pounded her back,and others yelled for help.Without hesitation,Charlie sprang into action.展开更多
The airflow around a vacuum tube maglev train operating at high speeds is complex.In addition,the effect of relevant parameters in such a transportation system on aerodynamic characteristics is crucial in the design a...The airflow around a vacuum tube maglev train operating at high speeds is complex.In addition,the effect of relevant parameters in such a transportation system on aerodynamic characteristics is crucial in the design and safety of the system.A three-dimensional(3 D)vacuum tube train model is established based on a vacuum tube test platform for rail transit.The effects of the initial ambient temperature and scale ratio on the aerodynamic characteristics are analyzed during the whole operational process in this study.The results mainly focus on each processs variations in the shock waves,choked flow,and drag.During acceleration,shock wave generation is advanced or delayed under different system parameters,which vary the aerodynamic drag.While the train runs at a constant speed,the time that a standard shock is generated and the length of the choked flow differ under the effects of the varying system parameters.In braking,the disappearance of shock waves and reflections of the expansion wave suddenly decrease the aerodynamic drag either earlier or later due to the varying system parameters.展开更多
1 The grandfather was choking on a mouthful of food,unable to breathe and unable to cough.The grandson,recalling the important lesson learned during the 8-13 Project organized by the Italian Red Cross⁃Poggi⁃Sermide Co...1 The grandfather was choking on a mouthful of food,unable to breathe and unable to cough.The grandson,recalling the important lesson learned during the 8-13 Project organized by the Italian Red Cross⁃Poggi⁃Sermide Committee,suggested performing the Heimlich manoeuvre(海姆立克急救法)on the elderly man.展开更多
This study investigates the unsteady flow characteristics of shale oil reservoirs during the depletion development process,with a particular focus on production behavior following fracturing and shut-in stages.Shale r...This study investigates the unsteady flow characteristics of shale oil reservoirs during the depletion development process,with a particular focus on production behavior following fracturing and shut-in stages.Shale reservoirs exhibit distinctive production patterns that differ from traditional oil reservoirs,as their inflow performance does not conform to the classic steady-state relationship.Instead,production is governed by unsteady-state flow behavior,and the combined effects of thewellbore and choke cause the inflowperformance curve to evolve dynamically over time.To address these challenges,this study introduces the concept of a“Dynamic IPR curve”and develops a dynamic production analysis method that integrates production time,continuity across multi-stage state fields,and the interactions between tubing flow and choke flow.This method provides a robust framework to characterize the attenuation trend of reservoir productivity and to accurately describe wellbore flow behavior.By applying the dynamic IPR approach,the study overcomes the limitations of conventional methods,which are unable to capture the temporal variations inherent in shale reservoir production.The proposed methodology offers a theoretical foundation for improved production forecasting,optimization of choke size,and analysis of wellbore tubing characteristics,thereby supporting more effective operational decision-making across different stages of shale reservoir development.展开更多
文摘In this paper, the method of aperture-field integral and GTD is used to calculate the radiationpatterns of choke horn. The influence of chokes' location was analyzed. The calculating results are inagreement with measurement data. The method presented in this paper can be used to solve problems ofN chokes.
基金supported by Important National Science & Technology Specific Projects (2008ZX05021-003)National Natural Science Funds (50974021)
文摘Based on the local resistance computation model for a choke valve and using the flow characteristics of choke valves, we studied the relationships between the back pressure of a parallel choke assembly and the opening extent of choke valves and developed a model to characterize the pressure regime of the manifold assembly. A comparison of pressure characteristic curves shows that a parallel choke manifold assembly has obvious advantages over the conventional serial type including high linearity of pressure-regulating characteristics curves, the elimination of the overshoot interval, wider effective regulating interval and the higher system security. Laboratory hydraulic experiments have validated the capability of a back pressure control model for the parallel choke assembly to accurately control pressure. This study is of great theoretical and practical significance to further improve the performance of chokes used in managed pressure well drilling.
文摘Surface chokes are widely utilized equipment installed on wellheads to control hydrocarbon flow rates.Several correlations have been suggested to model the multiphase flow of oil and gas via surface chokes.However,substantial errors have been reported in empirical fitting models and correlations to estimate hydrocarbon flow because of the reservoir's heterogeneity,anisotropism,variance in reservoir fluid characteristics at diverse subsurface depths,which introduces complexity in production data.Therefore,the estimation of daily oil and gas production rates is still challenging for the petroleum industry.Recently,hybrid data-driven techniques have been reported to be effective for estimation problems in various aspects of the petroleum domain.This paper investigates hybrid ensemble data-driven approaches to forecast multiphase flow rates through the surface choke(viz.stacked generalization and voting architectures),followed by an assessment of the impact of input production control variables.Otherwise,machine learning models are also trained and tested individually on the production data of hydrocarbon wells located in North Sea.Feature engineering has been properly applied to select the most suitable contributing control variables for daily production rate forecasting.This study provides a chronological explanation of the data analytics required for the interpretation of production data.The test results reveal the estimation performance of the stacked generalization architecture has outperformed other significant paradigms considered for production forecasting.
基金PetroChina Research Applied Science and Technology Project,“Shale Gas Scale Increase Production and Exploration andDevelopment Technology-Research and Application of Key Technology of Deep Shale Gas Scale Production”(No.2023ZZ21YJ01).
文摘In the context of post-stimulation shale gas wells,the terms“shut-in”and“flowback”refer to two critical phases that occur after hydraulic fracturing(fracking)has been completed.These stages play a crucial role in determining both the well’s initial production performance and its long-term hydrocarbon recovery.By establishing a comprehensive big data analysis platform,the flowback dynamics of over 1000 shale gas wells were analyzed in this work,leading to the development of an index system for evaluating flowback production capacity.Additionally,a shut-in chart was created for wells with different types of post-stimulation fracture networks,providing a structured approach to optimizing production strategies.A dynamic analysis method for flowback was also developed,using daily pressure drop and artificial fracture conductivity as key indicators.This method offers a systematic and effective approach to managing the shut-in and flowback processes for gas wells.Field trials demonstrated significant improvements:the probability of sand production was reduced,gas breakthrough time was extended,artificial fracture conductivity was enhanced,and the average estimated ultimate recovery(EUR)per well increased.
文摘Charlie,a father from Sunderland,was enjoying a meal with friends when sudden panic erupted at a nearby table.A woman began to choke,her face turning red as her breaths became shallow.Her friend wildly pounded her back,and others yelled for help.Without hesitation,Charlie sprang into action.
基金Project(2682023ZTPY061)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The airflow around a vacuum tube maglev train operating at high speeds is complex.In addition,the effect of relevant parameters in such a transportation system on aerodynamic characteristics is crucial in the design and safety of the system.A three-dimensional(3 D)vacuum tube train model is established based on a vacuum tube test platform for rail transit.The effects of the initial ambient temperature and scale ratio on the aerodynamic characteristics are analyzed during the whole operational process in this study.The results mainly focus on each processs variations in the shock waves,choked flow,and drag.During acceleration,shock wave generation is advanced or delayed under different system parameters,which vary the aerodynamic drag.While the train runs at a constant speed,the time that a standard shock is generated and the length of the choked flow differ under the effects of the varying system parameters.In braking,the disappearance of shock waves and reflections of the expansion wave suddenly decrease the aerodynamic drag either earlier or later due to the varying system parameters.
文摘1 The grandfather was choking on a mouthful of food,unable to breathe and unable to cough.The grandson,recalling the important lesson learned during the 8-13 Project organized by the Italian Red Cross⁃Poggi⁃Sermide Committee,suggested performing the Heimlich manoeuvre(海姆立克急救法)on the elderly man.
基金supported by National Natural Science Foundation of China(Grant No.52474029)National Natural Science Foundation for Young Scientists of China(A)(Grant No.52525403)+2 种基金National Major Science and Technology Projects under the 14th Five-Year Plan(Grant No.2024ZD1405105)Science and Technology Innovation Team Project of Xinjiang Uygur Autonomous Region(Grant No.2024TSYCTD0018)Xinjiang Uygur Autonomous Region.
文摘This study investigates the unsteady flow characteristics of shale oil reservoirs during the depletion development process,with a particular focus on production behavior following fracturing and shut-in stages.Shale reservoirs exhibit distinctive production patterns that differ from traditional oil reservoirs,as their inflow performance does not conform to the classic steady-state relationship.Instead,production is governed by unsteady-state flow behavior,and the combined effects of thewellbore and choke cause the inflowperformance curve to evolve dynamically over time.To address these challenges,this study introduces the concept of a“Dynamic IPR curve”and develops a dynamic production analysis method that integrates production time,continuity across multi-stage state fields,and the interactions between tubing flow and choke flow.This method provides a robust framework to characterize the attenuation trend of reservoir productivity and to accurately describe wellbore flow behavior.By applying the dynamic IPR approach,the study overcomes the limitations of conventional methods,which are unable to capture the temporal variations inherent in shale reservoir production.The proposed methodology offers a theoretical foundation for improved production forecasting,optimization of choke size,and analysis of wellbore tubing characteristics,thereby supporting more effective operational decision-making across different stages of shale reservoir development.
