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Buoyancy counteracts gravity and makes objects rise. With a value of 9.8 for the vertical direction you will get a natural behaviour, but it is also possible to accelerate or decelerate the bubbles with higher or lower values. You can also add horizontal components to influence the bubbles' motion. A click on RealFlow's → “Axis Setup” defines the vertical and horizontal axes. Click on "+" shows for sliders.
Bubbles min lifetime
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