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This parameter is defined as mass per volume unit and is different for each substance. “Density” does not change the fluid's behaviour, but it is possible to combine fluids from different domains, e.g. to mimic substances like oil and water. The unit is kilograms per cubic metre. The density of water is 1,000 kg/m3. Avoid very small values close to 0, because they can lead to instabilities.
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Internal Pressure
“Int “Internal Pressure” simulates the forces between nearby particles and pushes them apart - this makes the fluid fill a greater volume. This parameter is not available for "Dumb" particles.
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External Pressure
“Ext “External Pressure tries to limit a fluid’s expansion tendency and can be compared to atmospheric pressure. This parameter is not available for "Dumb" particles.
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