Jet device capable of improving cavitation performance of jet type centrifugal pump

The invention relates to a jet device capable of improving the cavitation performance of a jet type centrifugal pump. The jet device comprises a nozzle, a flow guide section, a mixing section, a hollow tube, a dispersing section and a pressure increasing hole. According to the jet device, when the jet type centrifugal pump runs under a large-flow-rate working condition, the pressure increasing hole designed in the hollow tube of the jet device can guide high pressure liquid from a pump chamber into a low pressure area in the hollow tube, so that the pressure of the low pressure area of the hollow tube can be increased, the cavitation which leads to vibration and noise in the hollow tube of the jet device can be inhibited, and the phenomenon that the lift of the jet type centrifugal pump decreases sharply due to the cavitation occurring in the hollow tube of the jet device can be reduced; a lift stopping point can be deviated close to large flow rate, so that the running range of the jet type centrifugal pump