The influence of height-to-width ratio of feed inlet on flow field characteristics and separation performance of the hydrocyclone with spiral inlet

Hydrocyclone with spiral inlet, whose preliminary separation characteristic can improve separation efficiency, draws extensive research attention. The geometrical dimension of the feed inlet is an important factor influencing the separation performance of hydrocyclone. In this paper, to further improve the separation performance of hydrocyclone with spiral inlet, the influence law of height-to-width ratio of feed inlet on flow field characteristics and separation performance is investigated with numerical simulation after verifying the reliability of the multiphase flow model. The results show that decreasing the height-to-width ratio of the feed inlet improves the pressure gradient and tangential velocity of the hydrocyclone. With the decrease in the height-to-width ratio of the feed inlet, the symmetry of the flow field is improved. The change in flow field characteristics makes coarse particles move away from the axis along the radial direction, decreasing the probability of misplacement of coarse particles into the overflow and improving separation accuracy. When the height-to-width ratio of feed inlet is 1:2, separation accuracy is the highest, and sharpness index of classification efficiency curve of hydrocyclone with spiral inlet reaches 0.61. These results are expected to provide a reference to improve the separation performance of hydrocyclone with the spiral inlet.