The Design And Dynamic Analysis Of Water-jet Pump

Water-jet propulsion is a special way of ship propelling. The thrust pushing the ship forward is not directly from the propeller but the counterforce of water. The research of water-jet pump about dynamic properties is thrust research. The key of thrust research is an accurate prediction of the thrust. Only by accurately forecasting the thrust, finding out the impact factors of thrust, can the water-jet pumps that meet the claims be designed in return.The dynamic characteristics research of water-jet pumps includes three steps. At first, design water-jet pump impeller and diffuser by streamline method. Then create three-dimensional solid modeling of designed impeller, diffuser, inlet section and nozzle by Pro/E software. Finally, study the thrust by theoretical analysis method that combines numerical simulation method and experimental research method. The thrust calculation formula and thrust coefficient under different design parameters of water-jet pump can be got through the theoretical analysis. The thrust rules can be got through the numerical simulation of water-jet pump. The thrust of water-jet pump increases with the increasing number of the impeller blade, first increases and then decreases with blade angle and the outlet diameter of nozzle, also the thrust of water-jet pump has nothing to do with the diffuser number. A new kind of test method of water-jet pump is put forward through experimental research. The test method is the combination of motor efficiency test, the water-jet pump thrust experiment and performance experiment are combined by the shaft power, to ensure the water jet propulsion pump thrust and the corresponding conditions. The contrast between experiment and the simulation verify the feasibility and the correctness of the numerical simulation. The maximum thrust difference between the experiment and numerical simulation data of the water-jet pump is6.61%, the maximum difference of the water-jet pump flow is3.18%.The research of water-jet pump thrust enrich the theoretical system of the water-jet pump, and provide some reference to improve the dynamic characteristics of water-jet pump.