Coefficient of variation (CoV)

The coefficient of variation is a statistical measure that describes the ratio of the standard deviation of the concentration distribution to the mean value across the pipe cross-section. The value can therefore be interpreted as the relative error of the target composition across the mixer cross-section.

Mathematically, it can take values between 0 and 1, where 1 indicates a completely segregated state (goodness of mixture 0 %) and 0 indicates a completely ideal mixture (goodness of mixture 100 %), which, however, cannot be achieved in reality. A coefficient of variation of 0.05 is generally considered technically homogeneous. This value is also referred to as a mixing quality of 95 %.

With a sample precision of 95 %, statistically 95 % of the samples fall within a range of +/- 10 % and around 68 % of all samples fall within a range of +/- 5 % of the target composition. This holds true for all normally distributed random experiments.