Attraction of the cylindrical magnets

Two coaxial cylindrical permanent magnets are pulled to each other.

Problem type:
Axisymmetric problem of magnetostatics

Geometry:

Two coaxial cylindrical permanent magnets model

D = 2" (50.8 mm) - magnet diameter;
l = 0.65" (16.51 mm) - magnet thickness;
δ=0.5" (12.7 mm) - gap between the magnets.

Given:
magnet grade N35, H_c = 954930 A/m, B_r = 1.26 T;

Task:
Calculate the pulling force between two coaxial cylindrical magnets.

Solution:
To calculate the correct result an integration contour is drawn in the air around one of the magnets.

Result:

Two coaxial cylindrical permanent magnets attraction simulation