The variances of macro- and micro- mixture fractions were used to represent the performance of macro- and micro-mixing.Multi-scale simulation and study of turbulent mixing in jet reactor were made and the characteristic times of macro- and micro-mixing were obtained under different operation conditions.The results showed that in the case of constant entrained flow velocity

the mixing time to reach complete mixing decreased when the nozzle velocity increased.In the case of constant nozzle velocity

the mixing time to reach complete mixing increased when the entrained flow velocity increased.In the case of constant velocity ratio of nozzle and entrained flow

the mixing time to reach complete mixing decreased when both velocities increased.In all the cases studied

the controlling step of the turbulent mixing in jet reactor was micro-mixing process.