Inductive heating is a fascinating process used in many industrial applications. It works by generating heat directly within an electrically conductive object when it's placed in a changing magnetic field. The key components include an alternating current source, an induction coil, and the conductive object to be heated.
The first step in inductive heating begins with an alternating electric current flowing through the induction coil. This AC current changes direction periodically, following a sinusoidal pattern. The frequency can range from 50 to 60 hertz for household applications, or much higher frequencies for industrial processes.
The second step involves the creation of a changing magnetic field. According to Ampère's law, the alternating electric current flowing through the coil produces a magnetic field around it. Since the current is constantly changing direction and magnitude, the magnetic field also changes rapidly, following the same sinusoidal pattern as the current.
In the third step, the changing magnetic field induces eddy currents within the conductive object. According to Faraday's law of electromagnetic induction, when magnetic flux through a conductor changes, it induces an electromotive force that drives electric currents. These circulating currents, called eddy currents, flow in closed loops within the metal object.
To summarize what we've learned about inductive heating: It's a process that uses changing magnetic fields to generate heat directly within conductive objects. An alternating current creates a magnetic field, which induces eddy currents in the metal object, and the resistance to these currents produces heat through Joule heating. This efficient heating method is widely used in industrial applications and induction cooking.