磁性材料在电磁结构中广泛应用,而传统(标准)部分元等效电路(partial element equivalent circuit,PEEC)方法对包含磁性材料的各种结构进行分析已无能为力。该文提出了基于几何平均距离和空间磁介质均匀化处理的磁性PEEC建模方法(magnet...磁性材料在电磁结构中广泛应用,而传统(标准)部分元等效电路(partial element equivalent circuit,PEEC)方法对包含磁性材料的各种结构进行分析已无能为力。该文提出了基于几何平均距离和空间磁介质均匀化处理的磁性PEEC建模方法(magnetic PEEC,MagPEEC),根据磁性材料边界单元切向磁通密度在边界两边的关系得到了载流磁性材料表面磁化面电流和传导电流的耦合系数矩阵,给出了仅用传导电流表示的系统方程。对矩形单元之间、矩形单元与线单元之间、线单元与线单元之间的各种几何平均距离(geometrical mean distance,GMD)进行了分析,得到了相应的计算公式,在此基础上导出了平均切向磁感应强度的计算公式,并应用于磁性材料的MagPEEC建模。通过有限元(finite element method,FEM)方法对两邻近金属板的新型MagPEEC建模方法进行了验证。展开更多
Near interfaces of solid and liquid,electric double layer has electro-viscosity effects.Theoretical study shows that this electro-viscosity will make friction coefficient increase in thin film lubrication.The purpose ...Near interfaces of solid and liquid,electric double layer has electro-viscosity effects.Theoretical study shows that this electro-viscosity will make friction coefficient increase in thin film lubrication.The purpose of this study is to verify the influence of electric double layer on aqueous lubrication in an experimental way.Experiments were done on a composite sliding block tester,with distilled water as basic lubricant.Two different methods were adopted in the experiments.One is to add external electric field on friction pair and the other is to change ionic concentration in lubricant with additive-KCL here.Both methods can make electro-viscosity change according to theoretical research.During experiments,friction coefficient and steaming potential were measured.Experimental results show that electro-viscosity has significant influence on friction coefficient when film is thin.Friction coefficient increases obviously under thin film situation when external electric field is added or ionic concentration of lubricant is changed.In addition,with the increase of concentration of KCL,friction coefficient increases quickly.Test results indicate that electro-viscosity has significant effects on aqueous lubricating performance.展开更多
文摘磁性材料在电磁结构中广泛应用,而传统(标准)部分元等效电路(partial element equivalent circuit,PEEC)方法对包含磁性材料的各种结构进行分析已无能为力。该文提出了基于几何平均距离和空间磁介质均匀化处理的磁性PEEC建模方法(magnetic PEEC,MagPEEC),根据磁性材料边界单元切向磁通密度在边界两边的关系得到了载流磁性材料表面磁化面电流和传导电流的耦合系数矩阵,给出了仅用传导电流表示的系统方程。对矩形单元之间、矩形单元与线单元之间、线单元与线单元之间的各种几何平均距离(geometrical mean distance,GMD)进行了分析,得到了相应的计算公式,在此基础上导出了平均切向磁感应强度的计算公式,并应用于磁性材料的MagPEEC建模。通过有限元(finite element method,FEM)方法对两邻近金属板的新型MagPEEC建模方法进行了验证。
基金National Science Foundation of China(50375052)National Science Foundation for Post-doctoral Scien-tists of China(2005037336).
文摘Near interfaces of solid and liquid,electric double layer has electro-viscosity effects.Theoretical study shows that this electro-viscosity will make friction coefficient increase in thin film lubrication.The purpose of this study is to verify the influence of electric double layer on aqueous lubrication in an experimental way.Experiments were done on a composite sliding block tester,with distilled water as basic lubricant.Two different methods were adopted in the experiments.One is to add external electric field on friction pair and the other is to change ionic concentration in lubricant with additive-KCL here.Both methods can make electro-viscosity change according to theoretical research.During experiments,friction coefficient and steaming potential were measured.Experimental results show that electro-viscosity has significant influence on friction coefficient when film is thin.Friction coefficient increases obviously under thin film situation when external electric field is added or ionic concentration of lubricant is changed.In addition,with the increase of concentration of KCL,friction coefficient increases quickly.Test results indicate that electro-viscosity has significant effects on aqueous lubricating performance.
