In which direction to dig about the miscalculation of the collision of two "liquid" balls in weightlessness in 2d?

Question

Mathematics

You can simplify everything to two dimensions. I think it will be hundreds of times easier.
Without millions of particles. You just need the appearance that some kind of oscillations occur on the surfaces of the new ball, and, possibly, when they do not directly hit each other (for example, with a parallel oncoming movement with a slight shift, so that they hit each other), some parts , which had the greatest load, were separated.

Answer 1

SPH - smoothed particle hydrodynamics.