Parameters to Quantify Mixing Efficiency of Static Mixers
The third in a series on static mixing, this article explains mixer-specific characteristics, outlining parameters used to assess mixer efficiency and the advantages and disadvantages of mixer types.
Depending on the material to mix and the pre-defined application, different mixer characteristics are of particular importance. This article focuses on characteristics that describe the properties of the mixer itself (mixer-specific characteristics) rather than the application system as a whole (system-specific characteristics).
The mixing efficiency of a mixer can be characterized by the pressure drop over the mixer length, by the shear rate to which the material is exposed to in the mixer, by the mixing quality, by the volume of material remaining in the mixer and by its residence time behavior (see Table 1). In order to obtain a quantitative and comparable description of these properties, dimensionless characteristics were defined. This makes it possible to evaluate the mixing efficiency independently of the material properties of the components to be mixed and the operating conditions.