Re: [TCML] hoop stress in primary coil

["Antonio Carlos M. de Queiroz" <acmdq@xxxxxxxxxx>]

jimlux wrote:
> Anyone have a cookbook approximation kind of equation for the hoop 
> stress in the primary? Or even, a single turn coil, given di/dt, etc.
I think that the stress on a single loop (or a coil) can be calculated 
as follows:

1- Obtain an expression for the inductance of the coil as function of 
the length x of the wire: L(x).
2- The energy stored in the loop with a current i is: E=0.5*L(x)*i^2
3- Differentiate the energy in relation to x. This gives the force along 
the wire: F=0.5*i^2*dL(x)/dx

If the inductance is expressed as function of other parameter, as the 
radius of the coil, the
length of the coil, or the gap length in a coil with core, the same 
formula gives the force that
tries to change the parameter.

(I wrote "I think" above because I could not locate this idea anywhere 
to use as reference...)

Antonio Carlos M. de Queiroz



_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla