Mixing with multiple circular turbulent jets

This paper presents the results of a laboratory study investigating chemica l mixing in an open channel with multiple circular turbulent jets. The expe riments were carried out for alpha, which is the ratio of the velocity of t he jets to that of the crossflow, varying from 8 to 16, with a combination of coflowing and crossflowing jets and only crossflowing jets. The number o f ports for the jets was varied for 20 to 36 and the spacing between the po rts was varied from 12d to 24d where d is the diameter of the ports. Concen tration measurements covered the relative distance x/d=2000, where x is the longitudinal distance from the diffuser. The dimensionless mixing distance alpha xm/d at which the standard deviation of the concentration field reac hed a value of 5% was equal to 25000 where x(m) is the mixing distance. The results indicate that a diffuser with turbulent crossflowing jets could be an alternative to mechanical methods for achieving mixing of chemicals in open channels in water treatment plants.