Abstract: Lineelectrode can be used as a source to simulate ship’ electric and magnetic fields. However, it is difficult to measure the electromagnetic field of lineelectrode in the seawater. The issue can be solved if the distribution of its electromagnetic field in the seawater can be calculated by measuring its electromagnetic field in the air. According to the calculation model of pointelectrode in the seawater under the condition of electric field of steady current, the analytic expressions of electric and magnetic fields of lineelectrode in the seawater and its magnetic field in air are derived, thereby proposing a method to reckon the parameters of lineelectrode and the distribution of its magnetic and electric field in the seawater by using the distribution of measured magnetic field in air. A scheme of experiment under the laboratory pool condition is designed, and the genetic algorithm is used to code the parameters of lineelectrode and the effective section of cable. The calculated result is in agreement with the actual result. The distributions of electric and magnetic fields in the pool are obtained from the measured result, which are close to the theoretical values.

Key words: electromagnetism, lineelectrode, medium model, mirror image