Time Step

– The amount of simulation time (in seconds) that passes during each frame.

– When Subframes is set to 0, Timestep is equal to the delta time (calculation frequency) used in the ODE Solver (see ODE Solver on Wikipedia).

– Default value is 0.04 as at 25 fps one frame duration is 0.04 seconds (1 frame / 25fps).

– In this example not only the the 1st flow of particles runs ‘slowler’ than the 2nd one, but also it is shorter as the same number of particles is emitted in half time.

Blender Particles Newtonian Integration Time Step