Velocity

The initial velocity of particles can be set through different parameters, based on the type of the particle system. If the particle system type is Emitter or Hair, then the following parameters give the particle an initial velocity in the direction of...

Emitter Geometry

Normal

The emitter’s surface normals (i.e. let the surface normal give the particle a starting speed).

Tangent

Let the tangent speed give the particle a starting speed.

Rotation

Rotates the surface tangent.

Emitter Object

Align

Give an initial velocity in the X, Y, and Z axes.

X, Y, Z

Object

The emitter objects movement (i.e. let the object give the particle a starting speed).

Random

Gives the starting speed a random variation. You can use a texture to only change the value, see Controlling Emission, Interaction and Time.