Magnetic field induced by current in a cylindrical wire

[annier]

You can pm me your email, I can forward u the pdf file.

[asandip]

I am attempting to compare the Elmer "max. magnetic flux density e" with theoretical max. magnetic flux density (using modified version* of equation 7.3 in Elmer GUI Tutorial) for a certain wire radii and length.

Two attempts listed below:
Wire radius = 7.976e-05, Wire length = 0.0012678
Elmer value = 1.29E-05
Theoretical value = 0.0001258


Wire radius = 0.000192, Wire length = 0.0005372
Elmer value = 7.08E-05
Theoretical value = 0.000717

They compare well except that in both cases, the Elmer value is off by an order. The coordinate scaling is: Coordinate Scaling(3) = 1.0e-4 1.0e-4 1.0e-3

I had two questions regarding this,

1. Why are the Elmer values off by an order?
2. *The modified version of equation 7.3 is, absolute max. magnetic flux density (theoretical) = (max. magnetic flux density using equation 7.3)/wire length, the Elmer values compare well with this number (apart from being off by an order). Does this mean that Elmer is solving for max. magnetic flux density per unit length?

Thanks for any information you can provide.

[kevinarden]

In your model the length of the wire is 0.005372 in your message you say it is 0.0005372.

[asandip]

Thanks! The scaling in the z direction is 1.0e-3 and not 1.0e-4 as I originally had. This fixes the order issue.

The modified version of equation 7.3 that I am using to calculate the theoretical value is: max. magnetic flux density using equation 7.3/wire length

The Elmer values compare well with this number. Does this mean that Elmer is solving for max. magnetic flux density per unit length?