This is my private work for FumeFX explosion's R&D. I call this explosion in the back "2 path explosion" and here is how I achieved the look.
I made a base explosion with Fluid Motion and had a huge amount of particles to follow it with FumeFX Follow.
Then, I ran final simulation with the particles that I created.
By using this method, I can have the explosion with much finer details than making it from regular fluid dynamics

j vimeo.com/8382829

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