The influence of new outlet configurations

which are designed with different internal baffles in the vortex finder and the underflow pipe

on the separation performance is investigated experimentally in a small hydrocyclone with a diameter of 50 mm. It is indicated that the vortex finder with internal baffles is suitable for the working conditions of a high throughput. Compared with that of traditional vortex finders

the separation efficiency of vortex finders with internal baffles in the hydrocyclone decreased slightly

but the pressure drop reduced remarkably to 11.11% at high flow rates. Three pieces of narrow and short baffles

which are spaced at regular intervals around the inner wall of the vortex finder

are recommended. It is found that the cross-shaped internal baffles in the underflow pipe can stabilize the inner vortex flow therein

and the separation efficiency can be improved by 5.96%. If the vortex finder and the underflow pipe are designed with the optimized baffles

the separation efficiency can be enhanced and meanwhile the pressure drop can be decreased. In addition

it is observed that the vortex finder with the internal baffles can eliminate the air core inside the hydrocyclone. It is inferred that the air core is not produced by air

but it is a forced swirl vortex with a high turbulence formed in the central zone with a negative gauge pressure.