The distribution of magnetic forces and current on sheet and coil was analyzed in detail according to the structural parameter of the coil which was invalid.The result shows that the current direction based on simulat...The distribution of magnetic forces and current on sheet and coil was analyzed in detail according to the structural parameter of the coil which was invalid.The result shows that the current direction based on simulation result agrees with the principles of uniform pressure electromagnetic actuator.The reason for coil failure was proposed.Then the magnetic forces on the sheet were input into an explicit finite element software ANSYS/LS-DYNA to analyze the deformation law of the sheet.展开更多
Single-walled carbon nanotubes(SWCNTs)are receiving immense research attention due to their tremendous thermal,electrical,structural and mechanical properties.In this paper,an exact solution of the dynamic response of...Single-walled carbon nanotubes(SWCNTs)are receiving immense research attention due to their tremendous thermal,electrical,structural and mechanical properties.In this paper,an exact solution of the dynamic response of SWCNT with a moving uniformly distributed load is presented.The SWCNT is modelled via the theories of Bernoulli-Euler-thermal elasticity mechanics and solved using Integral transforms.The developed closed-form solution in the present work is compared with existing results and excellent agreements are established.The parametric studies show that as the magnitude of the pressure distribution at the surface increases,the deflection associated with the single walled nanotube increases at any mode whilst a corresponding increase in temperature and foundation parameter have an attenuating effect on deflection.Moreover,an increase in the Winkler parameter,as well as a decrease in the SWCNT mass increases its frequency of vibration.Furthermore,an increase in the speed of the external agent decreases the total external pressure as a result of the removal of dead loads.The present work is envisaged to improve the application of SWCNT as nanodevices for structural,electrical and mechanical systems.展开更多
This paper seeks to investigate nonlinear out-of-plane mechanical behaviours of woven composite flexible skin(WCFS)through experimental and theoretical methods.Firstly,quasi-static experiments are carried out on recta...This paper seeks to investigate nonlinear out-of-plane mechanical behaviours of woven composite flexible skin(WCFS)through experimental and theoretical methods.Firstly,quasi-static experiments are carried out on rectangular WCFSs with different aspect ratios under uniform normal pressure to measure out-of-plane deformation and failure loads.Afterwards,a new three-parameter geometric model is presented to describe 3D geometry of pressurized WCFS,and thus,a nonlinear mechanical model is deduced for depicting the relationship between pressure and out-of-plane displacement.The application of the aforementioned models for experimental results shows that the new models have adequately and logically depicted deformation geometry and nonlinear mechanical characteristics.展开更多
As a core component of thermal systems in electric vehicles,the scroll compressor plays a crucial role in energy saving and emission reduction by enhancing its performance.The uniformity of pressure within the symmetr...As a core component of thermal systems in electric vehicles,the scroll compressor plays a crucial role in energy saving and emission reduction by enhancing its performance.The uniformity of pressure within the symmetrical working chambers of the scroll compressor significantly affected the work efficiency.This study utilizes computational fluid dynamics simulation technology to investigate methods for improving the uniformity of pressure within the symmetrical working chambers of a scroll compressor.First,the axial clearance on one side was calculated for the first time.The results indicate that when the axial clearance was located at the top of the orbiting scroll,the maximum pressure difference in the symmetrical working chambers decreased from 1.21 MPa to 0.83 MPa.Second,the groove at the beginning of the orbiting scroll can significantly enhance pressure uniformity.Under the calculation model provided in this paper,the average power of the scroll compressor can be reduced by 232.58 W,a reduction of 17.39%,through the groove.Finally,this study presents matching principles for the design of the groove and exhaust ports to ensure that both working chambers are simultaneously connected to the exhaust port.When the diameter of the exhaust port was reduced,and the size of the exhaust port did not match the groove,under the low-pressure-ratio working condition,the maximum pressure difference of the compressor increased by 0.20 MPa,and the average power increased by 158.95 W.The above conclusions have a significant reference value for improving the performance of scroll compressors and extending the driving range of electric vehicles.展开更多
Because ring-stiffened cylindrical shell structures have many merits, they are widely used in many areas. However, as the strength of steel increase continuously, ensuring of the structure stability is becoming more a...Because ring-stiffened cylindrical shell structures have many merits, they are widely used in many areas. However, as the strength of steel increase continuously, ensuring of the structure stability is becoming more and more important. Therefore, it is necessary to carry on a more particular analysis. Based on the understanding and analysis of the characteristics of stability for a ring-stiffened cylindrical shell under uniform external pressure and under external single pressure, the characteristics under different cross uniform external pressures are analyzed, and the regularity of it is also gotten. The curve of stability given various geometrical parameters under different cross uniform external pressures is protracted by the analysis of the theory. The conclusion not only improves the theory structural mechanics, it also was important effects on engineering calculation and design.展开更多
基金Project (50875093) supported by the National Natural Science Foundation of China
文摘The distribution of magnetic forces and current on sheet and coil was analyzed in detail according to the structural parameter of the coil which was invalid.The result shows that the current direction based on simulation result agrees with the principles of uniform pressure electromagnetic actuator.The reason for coil failure was proposed.Then the magnetic forces on the sheet were input into an explicit finite element software ANSYS/LS-DYNA to analyze the deformation law of the sheet.
文摘Single-walled carbon nanotubes(SWCNTs)are receiving immense research attention due to their tremendous thermal,electrical,structural and mechanical properties.In this paper,an exact solution of the dynamic response of SWCNT with a moving uniformly distributed load is presented.The SWCNT is modelled via the theories of Bernoulli-Euler-thermal elasticity mechanics and solved using Integral transforms.The developed closed-form solution in the present work is compared with existing results and excellent agreements are established.The parametric studies show that as the magnitude of the pressure distribution at the surface increases,the deflection associated with the single walled nanotube increases at any mode whilst a corresponding increase in temperature and foundation parameter have an attenuating effect on deflection.Moreover,an increase in the Winkler parameter,as well as a decrease in the SWCNT mass increases its frequency of vibration.Furthermore,an increase in the speed of the external agent decreases the total external pressure as a result of the removal of dead loads.The present work is envisaged to improve the application of SWCNT as nanodevices for structural,electrical and mechanical systems.
基金supported by the National Natural Science Foundation of China(Grant No.51875021)China Postdoctoral Science Foundation(Grant No.2022M720348).
文摘This paper seeks to investigate nonlinear out-of-plane mechanical behaviours of woven composite flexible skin(WCFS)through experimental and theoretical methods.Firstly,quasi-static experiments are carried out on rectangular WCFSs with different aspect ratios under uniform normal pressure to measure out-of-plane deformation and failure loads.Afterwards,a new three-parameter geometric model is presented to describe 3D geometry of pressurized WCFS,and thus,a nonlinear mechanical model is deduced for depicting the relationship between pressure and out-of-plane displacement.The application of the aforementioned models for experimental results shows that the new models have adequately and logically depicted deformation geometry and nonlinear mechanical characteristics.
基金the Key-Area Research and Development Program of Guangdong Province(Grant No.:2023B0909050005)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.:51721004)。
文摘As a core component of thermal systems in electric vehicles,the scroll compressor plays a crucial role in energy saving and emission reduction by enhancing its performance.The uniformity of pressure within the symmetrical working chambers of the scroll compressor significantly affected the work efficiency.This study utilizes computational fluid dynamics simulation technology to investigate methods for improving the uniformity of pressure within the symmetrical working chambers of a scroll compressor.First,the axial clearance on one side was calculated for the first time.The results indicate that when the axial clearance was located at the top of the orbiting scroll,the maximum pressure difference in the symmetrical working chambers decreased from 1.21 MPa to 0.83 MPa.Second,the groove at the beginning of the orbiting scroll can significantly enhance pressure uniformity.Under the calculation model provided in this paper,the average power of the scroll compressor can be reduced by 232.58 W,a reduction of 17.39%,through the groove.Finally,this study presents matching principles for the design of the groove and exhaust ports to ensure that both working chambers are simultaneously connected to the exhaust port.When the diameter of the exhaust port was reduced,and the size of the exhaust port did not match the groove,under the low-pressure-ratio working condition,the maximum pressure difference of the compressor increased by 0.20 MPa,and the average power increased by 158.95 W.The above conclusions have a significant reference value for improving the performance of scroll compressors and extending the driving range of electric vehicles.
文摘Because ring-stiffened cylindrical shell structures have many merits, they are widely used in many areas. However, as the strength of steel increase continuously, ensuring of the structure stability is becoming more and more important. Therefore, it is necessary to carry on a more particular analysis. Based on the understanding and analysis of the characteristics of stability for a ring-stiffened cylindrical shell under uniform external pressure and under external single pressure, the characteristics under different cross uniform external pressures are analyzed, and the regularity of it is also gotten. The curve of stability given various geometrical parameters under different cross uniform external pressures is protracted by the analysis of the theory. The conclusion not only improves the theory structural mechanics, it also was important effects on engineering calculation and design.
