The Influence of the Double-Conical Structure on the Grading Performance of the Full Cylindrical Hydrocyclone

Conventional dual-cone hydrocyclones can improve classification performance by adjusting the angles of the two cones. However, for a fully cylindrical hydrocyclone, the internal flow characteristics and the influence mechanism of the dual-cone design on separation performance remain unclear. This study investigates the effects of five different dual-cone configurations on the classification performance of fully cylindrical hydrocyclones through numerical simulation and experimental validation. Simulation results indicate that the hydrocyclone with the H₁:H₂ dual-cone configuration exhibits the highest static pressure and tangential velocity, accompanied by a more stable internal flow field. Numerical analysis indicates that when H1:H2 = 3:1, the cut size is 16.5 μm, and the sharpness index is 0.73. When H1:H2 = 5:3, the cut size is 18.3 μm, and the sharpness index is 0.62. Increasing the length of the upper cone section can effectively enhance the cutting ability and classification accuracy of the hydrocyclone. Experimental results further demonstrate that the H₁:H₂ configuration achieves the highest grade efficiency of up to 56.89% and the lowest underflow concentration, indicating superior separation performance compared with other cone structures. At H₁:H₂ = 3:1, the content of fine particles smaller than -25 μm in the underflow is the lowest, while the corresponding content in the overflow is the highest, resulting in the highest mass efficiency and optimal overall grading performance. These findings provide theoretical guidance and data support for the structural design of next-generation hydrocyclones.