Mutual inductance and coupling coefficient in 3D environment

[sharlotte]

if there are two solenoids d(cm) apart from each other (in 3D environment[x y z]); in other words, they are not laid on the same axis and the difference between the value of x and y and z (for S1 and S2) is not zero (see Figure please)
what would be the mutual inductance (M)?
or the coupling coefficient (k) equation?

Thanks
View attachment SS.bmp

 

[BigBoss]

It's hard to answer..
You should simulate those coils in 3D environment..