Eddy current (also called Foucault current) was discovered by French physicist Leon Foucault in 185 1 year. It is caused by the intersection of moving magnetic field and metal conductor, or the vertical intersection of moving metal conductor and magnetic field. In short, it is caused by electromagnetic induction effect. This action produces an electric current in the conductor.
brief introduction
When the current in one coil changes with time, induced current will be generated in another nearby coil due to electromagnetic induction. In fact, any conductor near this coil will produce induced current.
If such induced current is represented graphically, it looks like a vortex in water, so we call it eddy current induction.
Eddy current can be used for nondestructive testing and structural monitoring of various metal products, such as surface and near-surface testing of aircraft fuselage and parts.
When rowing a boat, it is also a similar situation to bring a local vortex on the water surface.
The above content reference: Baidu Encyclopedia-Vortex