Fluid seepage and associated heat transfer within the enhanced geothermal system(EGS)regulate the extraction of heat from hot,low-water-saturation thermal reservoirs,sometimes referred to as hot dry rock(HDR).To under...Fluid seepage and associated heat transfer within the enhanced geothermal system(EGS)regulate the extraction of heat from hot,low-water-saturation thermal reservoirs,sometimes referred to as hot dry rock(HDR).To understand these complex heat recovery processes,we simulated long-term heat extraction in a surrogate HDR using a true triaxial apparatus.A circulation test was first implemented to analyze the connectivity between different wells.Suitable injection and production wells were then selected for the laboratory heat extraction tests in granite,which lasted 14.5 h.Under variable injection rate conditions,we systematically analyzed the time-varying curves of temperature and flow rate in the production wells and pressure in the injection wells.Our findings showed that the advantage channel was dominant in the flow distribution when several paths existed in EGS.Changes in fracture conductivity are attributed to injection pressure.These included an increase in fracture width and activation of a localized closed area of fracture.These two mechanisms influenced the production temperature,and this is consistent with the field data monitored at the Fenton Hill and Hijiori projects.Fluid leak-off was an important factor affecting the production flow rate.For a fracture with low hydraulic conductivity,a lower injection rate could effectively prevent excessive fluid leak-off.In addition,by comparing injection rates and fluid recovery rates,production wells in different phases or injection modes had different fluid recovery rates even when the injection rates were the same.展开更多
Biosecurity issues have attracted widespread global attention.Biosafety laboratories are important sites for med-ical testing and scientific research.However,there is a high incidence of laboratory-acquired infections...Biosecurity issues have attracted widespread global attention.Biosafety laboratories are important sites for med-ical testing and scientific research.However,there is a high incidence of laboratory-acquired infections due to improper laboratory personnel practices.There is therefore an urgent need to study the exposure risks of labo-ratory personnel exposed to biosafety laboratories.In this study,Computational Fluid Dynamics(CFD)was used to simulate biological aerosols generated by improper experimenter handling under three typical scenarios and validated experimentally.The spatial and temporal distribution of biological aerosols was analysed in relation to the flow field and isosurface concentrations.Statistics on deposition rates and contamination levels on different surfaces.Through the flow field of a biological safety cabinet(BSC)and the concentration of biological aerosols within it.Analysed the protective properties of BSCs.Finally,using SARS-CoV-2 as a case study,infection risks in different regions were evaluated.The results show that airflow distribution is a key factor influencing the removal of biological aerosols.No significant difference in biological aerosol deposition rates between release source locations.Nearly 70 per cent of all biological aerosols are deposited on surfaces such as walls,equipment and humans.At the same time a significant portion of the biological aerosols will enter the BSC operating area through the front window opening.This can lead to a potential risk of cross-infection.This study provides guid-ance for priority disinfection locations in biosafety laboratories and for laboratory personnel to reduce exposure to high-risk areas.展开更多
KSSOLV(Kohn−Sham solver)is a MAT-LAB(Matrix Laboratory)toolbox de-signed for solving the Kohn-Sham density functional theory(DFT)equations by us-ing the plane-wave basis set.Leveraging the powerful capabilities of MAT...KSSOLV(Kohn−Sham solver)is a MAT-LAB(Matrix Laboratory)toolbox de-signed for solving the Kohn-Sham density functional theory(DFT)equations by us-ing the plane-wave basis set.Leveraging the powerful capabilities of MATLAB’s parallel computing toolbox and an ad-vanced,optimized calculation workflow,KSSOLV uniquely enables efficient graph-ics processing unit(GPU)acceleration,making DFT calculations accessible on standard personal computing hardware.Here,KSSOLV-GPU 2.0,as the latest release,demonstrates substantial computational gains.In benchmarks,particularly involving calculations such as hybrid functionals and spin-polar-ized systems for complex band structure analysis,KSSOLV-GPU 2.0 achieves a speedup of more than an order of magnitude compared to conventional central processing unit based im-plementations.This significant acceleration marks a pivotal advancement in performing com-plex materials simulations,making KS-DFT increasingly accessible on personal computing platforms.展开更多
The Jinping Underground Laboratory is the deepest and largest underground laboratory in the world,with a maximum buried depth of approximately 2400 m.The objective is to study the brittle-ductile transition of marble ...The Jinping Underground Laboratory is the deepest and largest underground laboratory in the world,with a maximum buried depth of approximately 2400 m.The objective is to study the brittle-ductile transition of marble through a combination of experimental research and constitutive modeling.Triaxial compression and triaxial cyclic loading tests are initially conducted to explore the accumulation of pre-peak plastic strain and the deterioration of stiffness of the marble.Then,a specific constitutive model is developed to accurately reflect the pre-peak plastic hardening and post-peak strain softening behaviors based on the deformation and failure mechanism of the marble.The incremental constitutive relationship of the proposed model is subsequently derived in detail,and the model parameters are calibrated using data obtained from the test results.Finally,the effectiveness of the proposed model is assessed by comparing its results with the experimental results of the marble.The findings show that the proposed model accurately predicts the behavior of the marble,and its results are in good agreement with the test data.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52192622)the Natural Science Foundation of Sichuan Province,China(Grant No.2025ZNSFSC0371)the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project(Grant No.SKLGP2022Z018).
摘要Fluid seepage and associated heat transfer within the enhanced geothermal system(EGS)regulate the extraction of heat from hot,low-water-saturation thermal reservoirs,sometimes referred to as hot dry rock(HDR).To understand these complex heat recovery processes,we simulated long-term heat extraction in a surrogate HDR using a true triaxial apparatus.A circulation test was first implemented to analyze the connectivity between different wells.Suitable injection and production wells were then selected for the laboratory heat extraction tests in granite,which lasted 14.5 h.Under variable injection rate conditions,we systematically analyzed the time-varying curves of temperature and flow rate in the production wells and pressure in the injection wells.Our findings showed that the advantage channel was dominant in the flow distribution when several paths existed in EGS.Changes in fracture conductivity are attributed to injection pressure.These included an increase in fracture width and activation of a localized closed area of fracture.These two mechanisms influenced the production temperature,and this is consistent with the field data monitored at the Fenton Hill and Hijiori projects.Fluid leak-off was an important factor affecting the production flow rate.For a fracture with low hydraulic conductivity,a lower injection rate could effectively prevent excessive fluid leak-off.In addition,by comparing injection rates and fluid recovery rates,production wells in different phases or injection modes had different fluid recovery rates even when the injection rates were the same.
基金supported by the National Key R&D Program of China(2023YFC2605300)the National Natural Science Foundation of China(No.52478090)+1 种基金the National Key R&D Program of China(2021YFF0604000)the Natural Science Foundation of Hebei Province(No.E2021502046).
摘要Biosecurity issues have attracted widespread global attention.Biosafety laboratories are important sites for med-ical testing and scientific research.However,there is a high incidence of laboratory-acquired infections due to improper laboratory personnel practices.There is therefore an urgent need to study the exposure risks of labo-ratory personnel exposed to biosafety laboratories.In this study,Computational Fluid Dynamics(CFD)was used to simulate biological aerosols generated by improper experimenter handling under three typical scenarios and validated experimentally.The spatial and temporal distribution of biological aerosols was analysed in relation to the flow field and isosurface concentrations.Statistics on deposition rates and contamination levels on different surfaces.Through the flow field of a biological safety cabinet(BSC)and the concentration of biological aerosols within it.Analysed the protective properties of BSCs.Finally,using SARS-CoV-2 as a case study,infection risks in different regions were evaluated.The results show that airflow distribution is a key factor influencing the removal of biological aerosols.No significant difference in biological aerosol deposition rates between release source locations.Nearly 70 per cent of all biological aerosols are deposited on surfaces such as walls,equipment and humans.At the same time a significant portion of the biological aerosols will enter the BSC operating area through the front window opening.This can lead to a potential risk of cross-infection.This study provides guid-ance for priority disinfection locations in biosafety laboratories and for laboratory personnel to reduce exposure to high-risk areas.
基金partly supported by the National Natural Science Foundation of China(42550106,22503093,22288201,22173093,21688102)the Innovation Program for Quantum Science and Technology(2021ZD0303306)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1170000,XDB0450101)the National Key Research and Development Program of China(2016YFA0200604,2021YFB0300600)the Anhui Province Science and Technology Innovation Project(202423k09020010)the University of Science and Technology of China-Southwest University of Science and Technology Counterpart Cooperation and Development Joint Fund(KY2490002501)the Dream Set Off-Kunpeng&Ascend Seed Program。
摘要KSSOLV(Kohn−Sham solver)is a MAT-LAB(Matrix Laboratory)toolbox de-signed for solving the Kohn-Sham density functional theory(DFT)equations by us-ing the plane-wave basis set.Leveraging the powerful capabilities of MATLAB’s parallel computing toolbox and an ad-vanced,optimized calculation workflow,KSSOLV uniquely enables efficient graph-ics processing unit(GPU)acceleration,making DFT calculations accessible on standard personal computing hardware.Here,KSSOLV-GPU 2.0,as the latest release,demonstrates substantial computational gains.In benchmarks,particularly involving calculations such as hybrid functionals and spin-polar-ized systems for complex band structure analysis,KSSOLV-GPU 2.0 achieves a speedup of more than an order of magnitude compared to conventional central processing unit based im-plementations.This significant acceleration marks a pivotal advancement in performing com-plex materials simulations,making KS-DFT increasingly accessible on personal computing platforms.
基金China Power Construction Group research project,Grant/Award Number:DJ-HXGG-2023-16National Natural Science Foundation of China-Yalong River Joint Fund Key Project,Grant/Award Number:U1965204+1 种基金National Natural Science Foundation of China,Grant/Award Number:52109143Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin(China Institute of Water Resources and Hydropower Research),Grant/Award Number:IWHR-SKL-KF202305。
摘要The Jinping Underground Laboratory is the deepest and largest underground laboratory in the world,with a maximum buried depth of approximately 2400 m.The objective is to study the brittle-ductile transition of marble through a combination of experimental research and constitutive modeling.Triaxial compression and triaxial cyclic loading tests are initially conducted to explore the accumulation of pre-peak plastic strain and the deterioration of stiffness of the marble.Then,a specific constitutive model is developed to accurately reflect the pre-peak plastic hardening and post-peak strain softening behaviors based on the deformation and failure mechanism of the marble.The incremental constitutive relationship of the proposed model is subsequently derived in detail,and the model parameters are calibrated using data obtained from the test results.Finally,the effectiveness of the proposed model is assessed by comparing its results with the experimental results of the marble.The findings show that the proposed model accurately predicts the behavior of the marble,and its results are in good agreement with the test data.