Simulated macromixing time-scales (s). The time-scale is the time required to reduce the concentration's standard deviation to 5 % of mean. The number of feed points is denoted by , and the letters, volumes, and stirrer speeds identify the vessels (Table and Figure ). The bottom row (1:1) shows reference mixing time-scales calculated with eq 5 in an equal-volume tank with 1:1 aspect ratio, one impeller, and an equal power input. the simulation results are summarized in Table . Compared with using a single top feed, at highest a 16-fold macromixing rate was obtained in the three-impeller configuration (B) and a 5.6-fold rate with two impellers (C). The single-impeller vessels (D) experienced approximately doubled mixing rates. As described in section 3.1, the dispersion model's capability of reproducing experimental tracer curves seemed to be proportional to the number of impellers (Figure ). Here a similar observation was made: in simulations the relative benefit of using multiple feed points correlated with the number of impellers.