LAUSR

ABSTRACT To optimize air-drawing capacity and working effectiveness of jet flotation machine’s stirring device, theoretical analysis has been performed on jet stirring device. Two jet stirring devices with different structural parameters have been designed, hydrodynamic governing equation of different parameters has been established, and pilot-scale test and particle image velocimetry (PIV) test experiments have been conducted in 6m3 test sink and 1.2m3 glass sink, respectively. The results show that flow core vanished apparently and air-drawing capacity improved because of diffuse fluid in the throat by adding the guide blade in the nozzle, which can diffuse fluid in the throat and improve air-drawing capacity; the air-drawing capacity of a long throat is better than that of a short one, besides, energy exchange and mixing effect of slurry and bubble in the former is better than the latter. The guiding blade in nozzle can guide fluid flowing, therefore reducing secondary eddy current and decreasing local loss by 10%~25%; the energy loss of jet stirring device is mainly from the throat, a two-fold increase of throat length leads to almost a threefold local resistance coefficient. Umbrella-shaped diffuser at the end of the throat goes against dispersion and mineralization of material.