id="p0005">Hydrocyclone efficiency was improved by designing vortex finder structure.
id="p0010">Vortex finder with extra conical shapes had high particle separation efficiency.
id="p0015">The simulation methods were verified by experimental data.
id="p0020">The sequence of particle separation efficiency was Type C > Type B > Type A.
id="p0025">The optimal designs were Types B-II and C-II.