TURBULENT MIXING OF 2 SPECIES WITH AND WITHOUT CHEMICAL REACTIONS

The mean of the product of the fluctuations of the concentrations of two species in a turbulent mixture is plus or minus 1 times the product of the RMS concentration fluctuations of the individual species when the molecular diffusivities of the two species are equal. In an ideal mixer the mean of the product of the fluctuations is simply related to the decay law of the mixer and the relationship is identical to that found for very rapid irreversibe second-order chemical reactions when the reactants are fed in stoichiometric proportions. Limited experimental data for slow irreversible reactions are consistent with the hypothesis that the mean of the products of the fluctuations with a slow reaction is independent of the speed of the reaction. © 1969, American Chemical Society. All rights reserved.