Here you can define the conditions for the emission of splash particles. The various threshold parameters will finally define where the splash particles will be created. Once you have finished the core fluid simulation you will be able to preview the areas of emission. Please read the following page to learn how to do this: → “Quick Start Workflows - Previewing Splash and Foam "Previews”.
Emission rate
This is the number of particles which are created per second per cubic metre. The final number of particles also depends on the various threshold values and the used particle type. In some cases it can be necessary to use very high settings of 1,000,000 and more.
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Sometimes, grid fluid simulations do not have enough splash particles, especially at lower resolutions. With “Yes”, new particles will be created when a splash particle enters the core fluid.
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Secondary bounce
This parameter is interesting for very strong splashes, for example from huge breaking waves, because you can adjust how much the splash particles will bounce against the grid fluid.
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Secondary radius threshold
A particles' radius ranges between 1 (birth) and 0 (death). Secondary splash particles will be created when a particles' radius is greater than the given value.