SPH - Square
"Square" emitters actually have exactly the same properties and characteristics as “Circle”, with one exception: with this emitter it is not possible to adjust something similar to “Ring ratio” – "Square" emitters always create particles over the entire area. For the emitter’s adjustments under "Node Params", please visit the appropriate manual section under “Circle”. Square emitters can be scaled with the "Node" panel’s “Scale” settings and you are also able to create rectangular shapes.
Volume
This feature creates a defined volume of particles. The dimensions of this volume consist of the emitter’s scale settings and the value entered here, based on RealFlow’s grid units. By activating this option, the emitter’s speed value will be set to 0.0 automatically.
Speed
Here you can define the emitter’s initial speed. Higher values will generate more particles per frame. Faster particles act with stronger forces on other particles or objects. The number of emitted particles also depends on your resolution settings. A value of 0.0 disables the emission of particles. This value can be animated either with keyframes or expressions. "Speed" is measured in metres per second [m/s].
V/H random
By default the particles are regularly emitted as a homogeneous stream, showing a kind of pattern.. To avoid and suppress this pattern, it is possible to randomly displace the particles with these functions. The values should range between 0 and 1, but can be higher, as well. “V” stands for vertical, while “H” means horizontal.
Side emission
Normally the particles are poured out along the emission axis. With this parameter set to “Yes”, a radial emission is performed from the outline of the emitter and the circle’s inner area remains empty.