Title : A study on the demagnetizing factor of a hollow cylinderical magnetic materials
Abstract:
Demagnetizing factors for both ellipsoidal and non-ellipsoidal bodies have been studied for more than 100 years. In the ellipsoid, the magnetic field inside the model is constant, so that the demagnetizing factor can be represented by one value. However, for non-ellipsoid, since the magnetic field inside the body is non-uniform, it is difficult to represent the demagnetizing factor as one value.
The hollow cylinder is usually used as an equivalent model for demagnetization of submarine. Since demagnetization requires very precise control, it is necessary to know the exact demagnetizing factor of the object. Previously, timothy Malcolm baynes proposed a method of calculating the demagnetizing factor of a hollow cylinder. It was predicted using the difference of the demagnetizing factors of two ellipsoids with different size. However, it isn’t reliable because there is a lack of verification of the results.
In order to verify the demagnetizing factor for hollow cylinder by this method, FEM analysis was performed.
