Estimating magnetic field from an electrical arc

[rasputin243]

Hi all,

I'm trying to develop a model of the magnetic field observed from electrical arcing. To start, I want to consider the example of arcing that sometimes occurs when you unplug a device (inductive load, for example) from a 120V, 60Hz outlet.

I searched for a while elsewhere online, and I didn't see any analytical approaches to estimating this magnetic field outside of very high-level equations and rules-of-thumb. My model would ideally take the following parameters into consideration:

-voltage
-current
-electrical frequency
-gap area
-gap length
-humidity (not essential)
-observation distance (and angle, if possible... a single axis is acceptable)

If anyone could provide some guidance as to what my approach should be, I would be grateful.

-rasputin243

 

[Bob S]

The azimuthal magnetic field B (in Tesla) at distance r (meters) from the arc is

$$B=\frac{\mu_0I}{2\pi r}$$

where μ₀ = 4π x 10^-7 and I is the current in amps.

This is Ampere's Law.

Bob S