The Self-Propping Phase-transition Fracturing Technology(SPFT)represents a novel and environmentally friendly approach for a cost-effective and efficient development of the world’s abundant unconventional resources,e...The Self-Propping Phase-transition Fracturing Technology(SPFT)represents a novel and environmentally friendly approach for a cost-effective and efficient development of the world’s abundant unconventional resources,especially in the context of a carbon-constrained sustainable future.SPFT involves the coupling of Thermal,Hydraulic,Mechanical,and Chemical(THMC)fields,which makes it challenging to understand the mechanism and path of hydraulic fracture propagation.This study addresses these challenges by developing a set of THMC multifield coupling models based on SPFT parameters and the physical/chemical characteristics of the Phase-transition Fracturing Fluid System(PFFS).An algorithm,integrating the Finite Element Method,Discretized Virtual Internal Bonds,and Element Partition Method(FEM-DVIB-EPM),is proposed and validated through a case study.The results demonstrate that the FEM-DVIB-EPM coupling algorithm reduces complexity and enhances solving efficiency.The length of the hydraulic fracture increases with the quantity and displacement of PFFS,and excessive displacement may result in uncontrolled fracture height.Within the parameters considered,a minimal difference in fracture length is observed when the PFFS amount exceeds 130 m^(3),that means the fracture length tends to stabilize.This study contributes to understanding the hydraulic fracture propagation mechanism induced by SPFT,offering insights for optimizing hydraulic fracturing technology and treatment parameters.展开更多
This paper explores the creation,development,and dissemination of prefabricated concrete rural houses in Jiangsu Province in East China from 1961 to the 1980s,an example of the technological transition provoked by the...This paper explores the creation,development,and dissemination of prefabricated concrete rural houses in Jiangsu Province in East China from 1961 to the 1980s,an example of the technological transition provoked by the depletion of forest and timber in China.Through archival research,fieldwork and interviews,the paper examines the two waves of design and dissemination of prefabricated concrete rural houses between 1961 and 1965 and their subsequent‘vernacularisation’in the 1970s and the 1980s.This research provides a twofold insight into the current scholarly debates surrounding built heritage and global climate change.On one hand,it addresses a historical context of concrete overuse in contemporary China,a matter of critical importance in relation to carbon emissions and global climate change.On the other hand,it offers a counter-argument to today’s call for reintroducing timber structures in many places,as evidenced by the case of East China,where the widespread use of materials like concrete was primarily a consequence of the ecological crisis following decades of deforestation and timber resource depletion.In addition,the‘vernacularisation’of concrete structures manifested by this case still provides lessons for today’s efforts to popularise more eco-friendly construction materials and technologies,especially in rural areas,and the prefabricated concrete houses possess potential heritage values as trackers of ecological changes.展开更多
基金supported by the National Natural Science Foundation of China(52179112)the Open Fund of National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Southwest Petroleum University)(PLN2023-02)Fundamental Research Funds for the Central Universities(2021FZZX001-14).
文摘The Self-Propping Phase-transition Fracturing Technology(SPFT)represents a novel and environmentally friendly approach for a cost-effective and efficient development of the world’s abundant unconventional resources,especially in the context of a carbon-constrained sustainable future.SPFT involves the coupling of Thermal,Hydraulic,Mechanical,and Chemical(THMC)fields,which makes it challenging to understand the mechanism and path of hydraulic fracture propagation.This study addresses these challenges by developing a set of THMC multifield coupling models based on SPFT parameters and the physical/chemical characteristics of the Phase-transition Fracturing Fluid System(PFFS).An algorithm,integrating the Finite Element Method,Discretized Virtual Internal Bonds,and Element Partition Method(FEM-DVIB-EPM),is proposed and validated through a case study.The results demonstrate that the FEM-DVIB-EPM coupling algorithm reduces complexity and enhances solving efficiency.The length of the hydraulic fracture increases with the quantity and displacement of PFFS,and excessive displacement may result in uncontrolled fracture height.Within the parameters considered,a minimal difference in fracture length is observed when the PFFS amount exceeds 130 m^(3),that means the fracture length tends to stabilize.This study contributes to understanding the hydraulic fracture propagation mechanism induced by SPFT,offering insights for optimizing hydraulic fracturing technology and treatment parameters.
文摘This paper explores the creation,development,and dissemination of prefabricated concrete rural houses in Jiangsu Province in East China from 1961 to the 1980s,an example of the technological transition provoked by the depletion of forest and timber in China.Through archival research,fieldwork and interviews,the paper examines the two waves of design and dissemination of prefabricated concrete rural houses between 1961 and 1965 and their subsequent‘vernacularisation’in the 1970s and the 1980s.This research provides a twofold insight into the current scholarly debates surrounding built heritage and global climate change.On one hand,it addresses a historical context of concrete overuse in contemporary China,a matter of critical importance in relation to carbon emissions and global climate change.On the other hand,it offers a counter-argument to today’s call for reintroducing timber structures in many places,as evidenced by the case of East China,where the widespread use of materials like concrete was primarily a consequence of the ecological crisis following decades of deforestation and timber resource depletion.In addition,the‘vernacularisation’of concrete structures manifested by this case still provides lessons for today’s efforts to popularise more eco-friendly construction materials and technologies,especially in rural areas,and the prefabricated concrete houses possess potential heritage values as trackers of ecological changes.
