We take the established inductively coupled plasma(ICP) wind tunnel as a research object to investigate the thermal protection system of re-entry vehicles. A 1.2-MW high power ICP wind tunnel is studied through numeri...We take the established inductively coupled plasma(ICP) wind tunnel as a research object to investigate the thermal protection system of re-entry vehicles. A 1.2-MW high power ICP wind tunnel is studied through numerical simulation and experimental validation. The distribution characteristics and interaction mechanism of the flow field and electromagnetic field of the ICP wind tunnel are investigated using the multi-field coupling method of flow, electromagnetic, chemical, and thermodynamic field. The accuracy of the numerical simulation is validated by comparing the experimental results with the simulation results. Thereafter, the wind tunnel pressure, air velocity, electron density, Joule heating rate, Lorentz force, and electric field intensity obtained using the simulation are analyzed and discussed. The results indicate that for the 1.2-MW ICP wind tunnel, the maximum values of temperature, pressure, electron number density, and other parameters are observed during coil heating. The influence of the radial Lorentz force on the momentum transfer is stronger than that of the axial Lorentz force. The electron number density at the central axis and the amplitude and position of the Joule heating rate are affected by the radial Lorentz force. Moreover, the plasma in the wind tunnel is constantly in the subsonic flow state, and a strong eddy flow is easily generated at the inlet of the wind tunnel.展开更多
Electric drive systems for new energy cars are complex systems that should have multivariate,strong coupling,and non-linear characteristics and should also involve the multiphysics field.The singular simulation softwa...Electric drive systems for new energy cars are complex systems that should have multivariate,strong coupling,and non-linear characteristics and should also involve the multiphysics field.The singular simulation software used at present in the modeling of electric drive systems cannot simulate the influences of all the physics fields on the operating system.The co-simulation model used in this paper was based on a specific type of car.The motor control algorithm model was built in MATLAB/Simulink,the electromagnetic finite element model of the motor was built in ANSYS EM-Maxwell,and the motor controller hardware circuit was built in ANSYS EM-Simplorer.To make real-time connections among these software platforms,a multi-software co-simulation platform was built,and the co-simulation platform’s simulation results were input into STAR CCM+software to enable finite element modeling of the motor and running of thermal analysis.When compared with the electric drive system model built using single Simulink software,the simulation results from this co-simulation platform were more realistic and were shown to be closer to reality when the dynamic characteristics of the electric drive system’s power semiconductor switching devices and the motor’s electromagnetic characteristics were considered.Finally,by benchmarking the multiphysics field co-simulation platform simulation results using dyno bench test results,the validity of the co-simulation platform was verified and the development of the multiphysics field co-simulation of the basic electric drive system was complete.展开更多
All-solid-state lithium metal batteries represent leading candidates for the next generation of highenergy-density rechargeable batteries.However,the coupled mechanisms governing dendrite growth and crack propagation ...All-solid-state lithium metal batteries represent leading candidates for the next generation of highenergy-density rechargeable batteries.However,the coupled mechanisms governing dendrite growth and crack propagation within solid-state electrolytes(SSEs)remain inadequately understood.To address this knowledge gap,we propose an electrochemical-mechanical coupled phase-field model designed to simulate the complex processes of lithium deposition and crack propagation in SSEs.This framework systematically examines the influence of initial defect characteristics—including morphology,dimensions,and fracture toughness—on dendrite penetration dynamics.Furthermore,it identifies potential initiation pathways for detrimental lithium deposition within the electrolyte bulk.The model also quantifies the critical role of electrolyte elastic modulus and grain boundary orientation in modulating deposition behavior.Notably,simulation results demonstrate concordance with existing experimental observations,thereby establishing a fundamental theoretical framework for understanding failure mechanisms.This work provides crucial mechanistic insights and predictive capabilities to guide the rational design of failure-resistant SSEs for all-solid-state lithium metal batteries.展开更多
Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing...Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing,and multiphysics field detec-tion.However,further enhancement of nonlinearity in photon avalanche nanomaterials remains challenging.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11705143)the Open Foundation for Key Laboratories of National Defense Science and Technology of China (Grant No. 6142202031901)the Foundation for Research and Development of Applied Technology in Beilin District of Xi’an,China (Grant No. GX2047)。
文摘We take the established inductively coupled plasma(ICP) wind tunnel as a research object to investigate the thermal protection system of re-entry vehicles. A 1.2-MW high power ICP wind tunnel is studied through numerical simulation and experimental validation. The distribution characteristics and interaction mechanism of the flow field and electromagnetic field of the ICP wind tunnel are investigated using the multi-field coupling method of flow, electromagnetic, chemical, and thermodynamic field. The accuracy of the numerical simulation is validated by comparing the experimental results with the simulation results. Thereafter, the wind tunnel pressure, air velocity, electron density, Joule heating rate, Lorentz force, and electric field intensity obtained using the simulation are analyzed and discussed. The results indicate that for the 1.2-MW ICP wind tunnel, the maximum values of temperature, pressure, electron number density, and other parameters are observed during coil heating. The influence of the radial Lorentz force on the momentum transfer is stronger than that of the axial Lorentz force. The electron number density at the central axis and the amplitude and position of the Joule heating rate are affected by the radial Lorentz force. Moreover, the plasma in the wind tunnel is constantly in the subsonic flow state, and a strong eddy flow is easily generated at the inlet of the wind tunnel.
文摘Electric drive systems for new energy cars are complex systems that should have multivariate,strong coupling,and non-linear characteristics and should also involve the multiphysics field.The singular simulation software used at present in the modeling of electric drive systems cannot simulate the influences of all the physics fields on the operating system.The co-simulation model used in this paper was based on a specific type of car.The motor control algorithm model was built in MATLAB/Simulink,the electromagnetic finite element model of the motor was built in ANSYS EM-Maxwell,and the motor controller hardware circuit was built in ANSYS EM-Simplorer.To make real-time connections among these software platforms,a multi-software co-simulation platform was built,and the co-simulation platform’s simulation results were input into STAR CCM+software to enable finite element modeling of the motor and running of thermal analysis.When compared with the electric drive system model built using single Simulink software,the simulation results from this co-simulation platform were more realistic and were shown to be closer to reality when the dynamic characteristics of the electric drive system’s power semiconductor switching devices and the motor’s electromagnetic characteristics were considered.Finally,by benchmarking the multiphysics field co-simulation platform simulation results using dyno bench test results,the validity of the co-simulation platform was verified and the development of the multiphysics field co-simulation of the basic electric drive system was complete.
基金supported by the National Natural Science Foundation of China(No.52476053,No.22409209)Beijing Natural Science Foundation(No.3242017)。
文摘All-solid-state lithium metal batteries represent leading candidates for the next generation of highenergy-density rechargeable batteries.However,the coupled mechanisms governing dendrite growth and crack propagation within solid-state electrolytes(SSEs)remain inadequately understood.To address this knowledge gap,we propose an electrochemical-mechanical coupled phase-field model designed to simulate the complex processes of lithium deposition and crack propagation in SSEs.This framework systematically examines the influence of initial defect characteristics—including morphology,dimensions,and fracture toughness—on dendrite penetration dynamics.Furthermore,it identifies potential initiation pathways for detrimental lithium deposition within the electrolyte bulk.The model also quantifies the critical role of electrolyte elastic modulus and grain boundary orientation in modulating deposition behavior.Notably,simulation results demonstrate concordance with existing experimental observations,thereby establishing a fundamental theoretical framework for understanding failure mechanisms.This work provides crucial mechanistic insights and predictive capabilities to guide the rational design of failure-resistant SSEs for all-solid-state lithium metal batteries.
文摘Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing,and multiphysics field detec-tion.However,further enhancement of nonlinearity in photon avalanche nanomaterials remains challenging.
