The fluxes [[PHI].sub.12](x, [x.sub.1], t) and [[PHI].sub.21](x, [x.sub.1], t) are the mutual magnetic fluxes of the two induction coils
in one TCR antenna and can be expressed as 
Figure 1 shows part of the molten metal pool and part of the induction coil
, distributed in relation to the vertical axis of symmetry.
With the induction coil
open (digital voltmeter, or DVM, very high impedance), there is virtually no current flow, and thus, no significant term for energy lost to resistive heating.
The ring-shaped multi-turn induction coil
was produced from copper pipe in the form of a spiral.
Using the developed simulation model, the initial computations were performed applying the operation frequency of 25 kHz with the aim to define the current density in induction coil
necessary for the formation of a good joint.
The fundamental operational difference between the two is the rate at which each applies power to the induction coil
under varying conditions.
Conventional methods of surge protection--like an induction coil
in a line, for example--exact power losses.
The topics discussed included induction heating basics, power supply choices, induction coil
designs and applications, induction heating problems and solutions, quench process and distortion control, unique applications, and many others.
This calibration step incorporates a high quality voltage reference (in practice a Josephson voltage standard), and uses the force coil as an induction coil
. If the force coil of an ampere balance is moved at constant speed v through the magnetic flux gradient produced by the second coil, then a voltage V is induced across it.
The induction coil
can be shaped to match the contours of the cavity, and the nature of induction heating--it is effective mainly for heating surface layers as the electromagnetic wave decays as it penetrates the conductor--suits it particularly to cavity surface heating.
Both the energy input and necessary impeder cross-section can be reduced by one of the following setup changes reduced vee angle (a 1.5[degrees] reduction in Vee angle equals a 100 kHz step down in frequency (Asperheim & Grande, 2009), less spring-back, shorter distance from induction coil
to weld point.