Rotary jet pump of improved volume efficiency and improvement method

The invention relates to a rotary jet pump of improved volume efficiency and an improvement method. The rotary jet pump of the improved volume efficiency comprises a housing of a cavity structure, a rotor assembly and an impact tube assembly, wherein the rotor assembly comprises a rotor cover and a rotation hub which are sealed and fastened, and form a rotor cavity, the rotor assembly is connected with a drive shaft, the impact tube assembly comprises a guide pipe and an impact tube which are connected into a whole, the impact tube is arranged in the rotor cavity, the guide pipe runs through the middle of the rotor cover, and is fixedly connected with the housing, the guide pipe and the rotor cover can relatively rotate, a portion of the guide pipe and a portion of the rotor cover, which are matched, are provided with a plurality of annular bulges and annular grooves, which are of certain axial length and arranged at intervals, and the guide pipe and the rotor cover are matched through the annular bulges and the annular grooves, and form an intercepting area. The improvement method of volume efficiency of an existing rotary jet pump includes: arranging the intercepting area which drains leakage fluid energy and enables the rotor cover and the guide pipe to not rub each other in relative movement between the matching portions of the rotor cover and the guide pipe, and enabling pressure of leakage fluid at the tail of the intercepting area to approximate to pressure of an annular inlet runner, and thereby achieving flow interception effects.