Add surface tension and magnetisation transfer
Particles get stuck on the surface for a random amount of time (drawn from an exponential distribution to reflect a constant probability of being released).
Detailed derivations in obsidian://open?vault=vault&file=how%20to%20model%20surface%20tension%20or%20realistic%20magnetisation%20transfer , which show that this also resolves #21 (closed)
Edited by Michiel Cottaar