Industrial mixer creates a stir
CSIRO's Rotated Arc Mixer mixes fluids that cannot be efficiently mixed with other technologies.
13 December 2007 | Updated 4 April 2013
CSIRO fluid engineers have invented an industrial mixer that is five times more energy efficient than traditional mixers.
The Rotated Arc Mixer (RAM) is also able to mix a range of fluids that other technologies are unable to mix efficiently.
Current mixing technologies, such as static mixers, can clog and develop material build-up that can result in production downtimes.
Stirred tank mixers, often used in the diary industry, can suffer from large stagnant regions that do not get mixed properly.
Some mixers are simply too rough and may destroy delicate ingredients. For example, sugarcane requires a delicate mix to preserve and encourage growth of crystals.
What CSIRO did
CSIRO fluid engineers:
- imagined what the ideal mixer might be like
- developed mathematical models to see how it would perform
- built the real thing.
Instead of beaters, blades or stirrers, RAM has two cylinders, one inside the other.
The outer cylinder rotates around the inner cylinder, which is fixed and has apertures cut into it at strategic locations.
As the outer cylinder rotates, fluid moves axially through the inner cylinder.
Drag from the outer cylinder acts on the fluid at each aperture in the inner cylinder, setting up a secondary cross-flow in the fluid.
Flow rate, rotation rate and the size of the apertures can be varied to suit different applications.
RAM lowers mixing energy costs around five times and successfully mixes fluids other technologies cannot mix efficiently.
RAM is able to mix:
paints and coatings
RAM is just as effective mixing batches or continuous flows.
Advantages of RAM include:
mixing twice as well as equivalent commonly used static mixers
consuming five times less energy
no stagnant areas
ease of cleaning
no internal surfaces for material to get caught on
easy scale-up as flow fields are the same irrespective of size
mixing very thick fluids.
Activity and application
RAM is also being developed as a tool for controlled heating or cooling of fluids, particularly viscous fluids.
This application would be particlularly valuable to the food industry.
RAM has undergone successful trials in several industries and has been licensed to equipment manufacturers supplying the food industry.
Discover CSIRO's capabilities in Simulating the flow of liquids, gases and particles.