This is an area emitter. An arrow indicates the node’s emission direction and helps you to point the emitter to a certain target. You can position (W key), rotate (E), and scale (R) this emitter.
Type
Toggle the emitter's type with this drop-down menu. The following parameters and the viewport representation will be updated according to your selection. Bear in mind that type changes will change the emitter's and fluid's behaviour completely.
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Here the particles' initial speed is defined in metres per second. 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 the domain's “Resolution” settings. A value of 0.0 → stops the emission of particles.
V random
To avoid regular emission, it is possible to randomly displace the particles with these functions. The value's range is between 0 and 1. “V” stands for vertical.
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