纵摇低磁舰船的涡流磁场计算

Calculation of the eddy current magnetic field of ship with weak magnetism waving lengthways

低磁材料舰船的磁性防护要求高,其中摇摆产生的涡流磁场占总磁场的比例很大,正确分析其涡流磁场具有重要意义。以低磁旋转椭球壳作为船体模型,从涡流磁场的电磁场方程及涡流密度的边值问题出发,建立了地磁场中纵摇旋转椭球壳涡流磁场的数学模型,利用分离变量法对涡流电流进行了求解,从而根据毕奥-萨伐定律推导出旋转椭球壳纵摇至任意角度产生的涡流磁场,为低磁钢壳体舰船纵摇的涡流磁场分析论证提供了理论基础。

To the ship with weak magnetic field,the demand on degaussing is very strict. In all the fields of that ship,the eddy current magnetic field plays important role,therefore it is very important to analyze the eddy current magnetic field of ships with weak magnetic field. The ellipsoid shell with weak magnetic field is used as the model of ships. Based on the electromagnetic field equation of eddy current and the boundary-value problem of eddy current density,the mathematics model of the eddy current produced by the ellipsoid shell with low magnetic field waving lengthways in the earth magnetic field was found. And the eddy current was obtained by separating variables method,then based on the Biot-Savart law,the eddy current magnetic field of the ellipsoid shell waving lengthways to an arbitrary angle is deduced,which provides theory base for the analysis of the eddy current magnetic field produced by the ellipsoid shell with low magnetic field waving lengthways.