Coefficient of Variation
• CoV is the mixing objective
• CoV is a method of specifying &
comparing the performance of
motionless mixers
• CoV = 0.05 is the industrially
accepted standard
• Where the CoV is achieved is
very important to specify
Pipe Mixers : Channel & Duct Mixers : Gas Dispersion Systems : Chemical Dosing Lances
Testing CoV
Laser Induced
Fluorescence Rig
(LIF)
Pipe Mixers : Channel & Duct Mixers : Gas Dispersion Systems : Chemical Dosing Lances
At a CoV of 0.05, 95% of all concentrations measured in the same plane
after mixing will fall within ±10% of the mean dosed concentration.
At a CoV of 0.01, 95% of all concentrations measured in the same plane
after mixing will fall within ±2% of the mean dosed concentration.
A CoV of 0.05 can be considered as a standard for water treatment applications.
Pipe Mixers : Channel & Duct Mixers : Gas Dispersion Systems : Chemical Dosing Lances
Two shots from LIF rig at
the same alpha & NRe
Statiflo CoV = 0.05
Courtesy of
Competitors CoV = 0.2
Pipe Mixers : Channel & Duct Mixers : Gas Dispersion Systems : Chemical Dosing Lances