- #1

Sh_lm

- 2

- 2

- Homework Statement
- Modelling a metal detector

- Relevant Equations
- ∇×E=− ∂/∂t(∇×B)

∇×B=μ0ε0∂/∂t(E)

I'm trying to model a metal detector for my internship project.

The system consist of one coil energised with an oscillator to create a magnetic field. The principle of the detection is by measuring the change in the coil impedance.

with biot et savart law the magnetic field create by the coil is expressed

where

Bem(r) : the magnetic field create by the coil

N : number of loops

Iem : current flowing through the coil

Rem : radius of the coil

r : distance from a given point in space to a point on the perimeter of the coil

The induced voltage in the target is given with faraday's law

where phi is the magnetic flux

I'm trying to find the expression of Bind the magnetic induced by eddy currents.

This is my results :

Now I've got a problem. Does Bind have a particular form? something like Bind = B0eiwt? or anything else? I need these results to start simulations so any help is welcomed thank you very much

The system consist of one coil energised with an oscillator to create a magnetic field. The principle of the detection is by measuring the change in the coil impedance.

with biot et savart law the magnetic field create by the coil is expressed

where

Bem(r) : the magnetic field create by the coil

N : number of loops

Iem : current flowing through the coil

Rem : radius of the coil

r : distance from a given point in space to a point on the perimeter of the coil

The induced voltage in the target is given with faraday's law

where phi is the magnetic flux

I'm trying to find the expression of Bind the magnetic induced by eddy currents.

This is my results :

Now I've got a problem. Does Bind have a particular form? something like Bind = B0eiwt? or anything else? I need these results to start simulations so any help is welcomed thank you very much