Investigation of the simultaneous volumetric 3-component flow field inside a hydrocyclone

The separation mechanism of hydrocyclone is elucidated by determining the three velocity components of the flow field. In this study, volumetric 3-component velocimetry measurement system was developed to investigate the three-dimensional three-component flow field inside a 35 mm mini-hydrocyclone. Measurement results show the magnitude of maximum tangential, axial, radial velocity component in r-z plane of the cylindrical and cone part is about 4:2:1. The parameter n of tangential velocity in the free vortex area is fitted to be 0.5-0.7, which is a variable along axial direction. Radial velocity is non-axisymmetric, while the other two are quasi-axisymmetric. The asymmetry of the radial velocity is found to be the consequence of the existing downward progression of secondary vortices. In addition, the locus of vertical velocity was constructed in three dimensional and the shortcut flow rate was calculated using three dimensional axial velocity. These knowledge helps the further understanding of the separation mechanism of the hydrocyclone.