Figure 1: Experimental device and system. (a) Internal structure view of compound hydrocyclone ( inlet pipe; vertex finder pipe; apex pipe; rotating blade; overflow outlet; holes; overflow chamber). (b) The symbols of structure parameters. (c) Diagram of experimental system ( slurry pump; split-flow valve;    and    electromagnetic flowmeter;    and    pressure gauge; compound hydrocyclone; water tank; mixing machine; variable-frequency drive; electric motor; laser tachometer). (d) The photo of experimental system.