| Waterjet propulsion is a kind of special propulsion way, which has been widely used in high-performance ships. Waterjet pump as the main body of waterjet propulsion system has higher requirements compared with ordinary pumps in the over-current capability, pump efficiency, anti-cavitation performance and structure, etc. Therefore, the design of high flow, high efficiency and good performance of anti-cavitation waterjet pump is a problem that urgent to be solved.Based on the two families of stream line surfaces theory, using the singularity distribution method, the quasi-three-dimensional inverse problem design of water- jet pump can be solved according to the shape of the meridional passage, the velo- city moment distribution and the blade thickness distribution. And a computer co- de is made in FORTRAN language to carried out this process of inverse problem design.The three-dimensional model of waterjet pump was made with software Pro/Engineer, and FLUENT was used to simulate the flow inside. According to calculation, the head, efficiency, shaft power of pump were estimated. By analyzing the internal pressure distribution and velocity vector distribution of pump, the flow situation was grasped and the cavitation zone was predicted.In the inverse problem design process, a variety of options were tried for the design of blade, including changes of velocity-moment distribution along the meridional flow lines, inlet angle of blade, location of maximum thickness of blade and so on. By numerical simulation to analyze these options and ultimately selected the option which meet the design requirements. The results showed that: (1) Controlling of the distribution of velocity-moment can effectively control the blade load distribution, thus ensuring the anti-cavitation performance of pumps to some extent. (2) Inlet angle of pump blade has a strong effect on pump performance. According to the design operating point, a appropriate inlet angle can ensure the efficiency as while as good anti-cavitation performance. (3) By calculating we can see that the location of maximum thickness of blade also has a strong effect on anti-cavitations performance of pumps. Shifting the location of maximum thickness of blade backward can improve the anti-cavitation performance of pumps. (4)The positions of blade inlet edge also have a substantial change in the structure and characteristics of the pump. According to all the calculation of different options, beneficial references can be provided for improving design of the waterjet pump.Finally, the final design of waterjet pump was defined based on the previous calculation and analysis, improving speed, and pump performance can be predicted through flow field calculation.
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