Explosion of particles in volume

[mp_i]

I just started using TyFlov. Help me please. I need to create an explosion of a pile of sand. The central part should explode - rise up in a column, swirl and then fall down (it should look like an explosion of a nuclear bomb). I have sand particles distributed over the volume of an ordinary cone. And when an explosion occurs, the central part of the particles should fly upward, and the rest remain in place.
I tried to indicate let the PathFollw and apply force, but everything acts on all the generated particles. How can only the central part be made to explode?