"Liquid” particles can be used to create very realistic and convincing splashes, especially when you want to combine core fluid particles and splashes within a single mesh. One of the main attributes of this particle type is “Viscosity” that can be used to simulate different types of fluid. When you switch to “Liquid” you will most probably get much fewer particles than with “Dumb”. In this case you should increase the emitter’s “Resolution” parameter. Please also bear in mind that simulations with “Liquid” particles take much longer.
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If you do not want to use the “Dumb” type you can also switch to “Liquid”“Liquid - Particles” or "Liquid - Hybrido". Simulations with liquid particles "Liquid - Particles" take much longer, but they also create very realistic results, especially for mid-scale simulations. Other types, like “Elastics” or “Gas” are not available with HySPH emitters. . With "Liquid - Hybrido" the particles will be controlled by RealFlow's Hybrido solver.
Density
A fluid's “Density” value does not influence the simulation and you can use any value. This changes when there is more than one particle fluid source and you want to achieve a certain effect, for example fluids that cannot mix, like water and alcohol. The parameter's unit is kilograms per cubic metre [kg/m3].
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