Contraposing a swirl nozzle for aerodynamically dispersing superfine powder

the Reynolds stress model was used to simulate the strongly swirling

compressible and transonic gas flow inside and outside the nozzles with different inlet angles and exit-cone angles.Meanwhile

combined with discrete phase model

a further study was conducted on the tracks and concentration distribution of particles between 1μm and 10μm.The results show that it has little effect on the swirl strength and turbulence intensity when changing the inlet angle.However

the swirl strength changes significantly in the nozzles

when the exit-cone angle is changed.The critical diameter of particles which can escape from swirl nozzle decreases as the particle density or exit-cone angle goes up

or as the inlet angle decreases.In the rear of the swirl nozzle

in order to obtain a good uniformity of concentration distribution

particles need to diffuse through a distance of about 20 times of the diameter of the nozzle outlet.