In my current research, I am looking at calculating the local porosity of a porous media in cylindrical coordinate (notably, two co-centric cylinders).
To obtain an accurate approximation, I need to calculate the area of intersection between the surface of a cylinder with a radius $R$ for which the axis is in $(0,0,0)$ and a sphere of radius $r<R$ for which the center can vary (i.e it can be anywhere between the two co-centric cylinders).
Could somebody point me in the direction of an analytical solution to calculate the area of intersection between these two surfaces or at least a fast algorithm?
Best regards, BB