A liquid whistle is a
static mixer
A static mixer is a precision engineered device for the continuous mixing of fluid materials, without moving components. Normally the fluids to be mixed are liquid, but static mixers can also be used to mix gas streams, disperse gas into liquid o ...
which passes fluid at high pressure through an orifice and over a blade. This subjects the fluid to high
turbulence
In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between ...
and may result in
mixing or
emulsification.
References
Laboratory equipment
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