I understand that the definition of flux linkage as kind of the sum of all the fluxes going through the surfaces bound by all the turns. That is, $\Lambda = N \Phi $. However what I don't understand is what happens if the coils are not uniformly stacked up on top of each other like a solenoid. For example, take the example of a sphere with N turns of wire wrapped around it to create some sort of spherical solenoid and run a time varying magnetic field through it. In this case, there should be a voltage induced however I don't understand how to employ the concept of flux linkage to calculate that here because $\Lambda \neq N \Phi$ as every loop of wire links a different amount of flux to the current. If anybody could help me understand how to use linkage here to solve for induced voltage or self inductance that would be great.