Reimagining Static Mixing

Project Story

Challenge

In-line static mixers are complex assemblies used across the polymer, plastics, pulp, food and energy industries. They provide low-shear blending of raw materials or ingredients, often held at a constant temperature. Because of manufacturing constraints, mixing and heat exchange were poorly integrated. In conventional helical baffled mixers, it is hard to increase mixing for a given length without increasing pressure drop.

Approach

Starting from first principles and taking inspiration from braiding, three or more strands are interlaced diagonally, and each one zigzags forward through the others. We explored whether this pattern could control how viscous and immiscible fluids were divided and recombined while keeping shear low. CFD simulations showed how the braided structures behaved during mixing.

Solution

The braided mixer was designed specifically for AM. Its channel profiles were tailored to remove areas of low or stagnant flow, which also makes cleaning and maintenance easier.

Outcome

Simulations confirmed a drastic change in fluid behaviour, with effective folding of the two fluids. The project showed how purpose-designed geometries can fully exploit AM, unlike generic preset geometries that fill a volume without regard to flow. This is our definition of Design for Additive Manufacturing.