Goodness of mixture

Mixing quality is a measure of the homogeneity or uniformity of a mixture and is calculated using basic statistical parameters. The most commonly used measure is the coefficient of variation.

When designing static mixers, it is necessary to determine which type of mixing element and how many mixing elements are required to achieve the desired mixing quality with an acceptable pressure drop.

The desired mixing quality depends on the specific application. For example, a coefficient of variation of 0.05 (mixing quality 95 %) indicates a technically homogeneous mixture, which is sufficient for most applications. For more demanding mixing tasks, such as the blending of paints or the homogenisation of gas streams, lower values may be required, such as a coefficient of variation of 0.01 (mixing quality 99%).

In simple mixing applications, just a few elements are often sufficient to achieve very good homogeneity. An example of this is the mixing of low-viscosity components such as water, which dissolve easily into one another. In other cases, twenty or more elements are required to achieve an acceptable result.