双桨船轴频电场建模与仿真

Simulation of Shaft-rate Electric Field of Two-propellers Ship

船体由于腐蚀会产生腐蚀电流,螺旋桨-轴的转动调制腐蚀电流在海水中产生低频电场。船模电场测量实验表明,轴频电场与轴转动频率有关,其基频与轴转动频率一致的。采用一对处于相同位置的运动时谐垂直电偶极子,偶极子的频率于轴转动频率一致,建立空气-海水-海床三层模型下的双桨船轴频电场模型,进行了不同轴频频率和不同轴电流初始相位情况下的轴频电场仿真分析,结果表明,轴转动频率和初相位对轴频电场有较大影响。

In sea water, by the electric potential difference between the hull and the propeller, corrosion current will be produced. As the shaft roating ,it will bring out the shaft-rate（SR） electric field signature. Many ships have two propellers. This paper study the relationship between the rotate frequency and the frequency of the electric field of two-propeller ship by experiments . The electric field model of moving vertical harmonic electric dipole（VED） in 3-layer medium has been built. Through simulation,we have got the SR electric field with different frequency and phase. Simulation result shows that the frequency and phase have great influence on the SR electric field.