Concentration correlation in a turbulent mixing layer with chemical reactions

Instantaneous concentrations of two reacting species were simultaneously measured using a combined laser and electrode-conductivity technique in a turbulent liquid mixing layer with the influence of second-order irreversible chemical reactions. To investigate the effect of turbulent mixing on the mean reaction rate, the concentration correlation was estimated from the instantaneous concentration measurements for three reactions; a very slow reaction, a moderately fast reaction and a rapid reaction, and the results were compared with several closure models. The results show that the segregation parameter increases from –1 towards zero in the downstream region of the mixing layer and it approaches –1 with increasing Damkohler number. The corrected 3E closure model can best predict the concentration correlation for both moderately fast and rapid reactions. The Lagrangian stochastic model can explicitly predict the concentration correlation for all reactions though it underestimates the correlation.