This study responds to global climate concerns by addressing the shift towards sustainable transportation,particularly electric vehicles.Focusing on wireless power transfer to overcome charging infrastructure challeng...This study responds to global climate concerns by addressing the shift towards sustainable transportation,particularly electric vehicles.Focusing on wireless power transfer to overcome charging infrastructure challenges,the research optimizes circular coils for inductive power transfer in electric cars.Utilizing ferrite cores to enhance performance,the study employs ANSYS Electronics Suite R2-202 and the finite element method to analyze circular coils,exploring variations in turns,inner radius,air gap,and misalignment's impact on the coupling coefficient.Introducing ferrite plan cores and boxes,the research finds that ferrite boxes improve coupling efficiency by 50%and electromagnetic field strength by 300%,concentrating the field toward the center.An inequivalent design,enlarging the primary coil,demonstrates significant enhancements,achieving a coupling coefficient increase of 0.183,447 and an electromagnetic field rise of 0.000,40 T.Equivalent coils with ferrite boxes meet a 95%efficiency goal with a strong,narrowed field at a lower cost,while inequivalent coils excel in strengthening and centralizing the field,enhancing misalignment tolerance in distinctive ways.展开更多
Numerical method is used to investigate fully developed laminar flow in helically coiled circular tube in this paper.The non-dimensional parameter(secondary flow Reynolds number Se)based on absolute vorticity flux alo...Numerical method is used to investigate fully developed laminar flow in helically coiled circular tube in this paper.The non-dimensional parameter(secondary flow Reynolds number Se)based on absolute vorticity flux along the mainstream is used to indicate the intensity of secondary flow caused by the centrifugal effect in helically coiled circular tube.The relationship between the intensity of secondary flow and the intensity of laminar convective heat transfer is studied.The effects of curvature and torsion on the enhancement of heat transfer are also considered.The results reveal that the absolute vorticity flux along the mainstream can be used to indicate the local or averaged intensity of secondary flow;the non-dimensional parameter of the absolute vortex along the main flow determines the convective heat transfer and friction factor.The relationships of Nusselt number and friction factor with the Se are obtained.The effect of curvature on Nusselt number is obvious,but the effect of torsion on Nusselt number is less obvious.展开更多
基金supported by the German Academic Exchange Service(DAAD)and the Federal Ministry for Economic Cooperation and Development(BMZ),Germany,within the framework of the REMO project(Renewable Energy-based E-Mobility in Higher Education),Grant Number:57545562.
文摘This study responds to global climate concerns by addressing the shift towards sustainable transportation,particularly electric vehicles.Focusing on wireless power transfer to overcome charging infrastructure challenges,the research optimizes circular coils for inductive power transfer in electric cars.Utilizing ferrite cores to enhance performance,the study employs ANSYS Electronics Suite R2-202 and the finite element method to analyze circular coils,exploring variations in turns,inner radius,air gap,and misalignment's impact on the coupling coefficient.Introducing ferrite plan cores and boxes,the research finds that ferrite boxes improve coupling efficiency by 50%and electromagnetic field strength by 300%,concentrating the field toward the center.An inequivalent design,enlarging the primary coil,demonstrates significant enhancements,achieving a coupling coefficient increase of 0.183,447 and an electromagnetic field rise of 0.000,40 T.Equivalent coils with ferrite boxes meet a 95%efficiency goal with a strong,narrowed field at a lower cost,while inequivalent coils excel in strengthening and centralizing the field,enhancing misalignment tolerance in distinctive ways.
基金supported by the National Natural Science Foundation of China(No.51776093,No.52066009)Transformation of S&T achievements in Universities of Gansu Province of China(No.2019C-06)+1 种基金Major Special Projects of Gansu Province of China(21ZD4GA027)Young Scientists Fund of Lanzhou Jiaotong University(2020038)。
文摘Numerical method is used to investigate fully developed laminar flow in helically coiled circular tube in this paper.The non-dimensional parameter(secondary flow Reynolds number Se)based on absolute vorticity flux along the mainstream is used to indicate the intensity of secondary flow caused by the centrifugal effect in helically coiled circular tube.The relationship between the intensity of secondary flow and the intensity of laminar convective heat transfer is studied.The effects of curvature and torsion on the enhancement of heat transfer are also considered.The results reveal that the absolute vorticity flux along the mainstream can be used to indicate the local or averaged intensity of secondary flow;the non-dimensional parameter of the absolute vortex along the main flow determines the convective heat transfer and friction factor.The relationships of Nusselt number and friction factor with the Se are obtained.The effect of curvature on Nusselt number is obvious,but the effect of torsion on Nusselt number is less obvious.
