Abstract: In order to balance the torque of front rotor and rear rotor of underwater vehicle， the analysis of the speed triangles at the inlet and outlet of the front and rear rotor has been done. Then， the thought of using contra-rotating pumpjet to achieve the objective was raised. The stator is installed behind the rear rotor so as to ensure the overall torque of the propulsor balance. At the same time，the stator can also support the shroud of the propulsor. The parametric design of the rotor and the stator has been carried out based on a hypothesis of velocity moment between the front rotor and the rear rotor，and between the rear rotor and the stator by using the three dimensional inverse design method. At last，the performance of the designed pumpjet propulsor is obtained when the pumpjet is installed on the underwater vehicle by using computational fluid dynamics. The results show that the total torque of the propulsor is reduced to 1.8N·m on the design point although the power difference ratio of the front rotor and the rear rotor is 20%. The torque ratio is also reduced from 4.6% to 0.4%，which is good to meet the propulsor balance requirement and verifies the 3-D design method of pumpjet and the thought of the pumpjet construction is useful.

Key words: Underwater vehicle；Contra-rotating pumpjet；Three dimensional design theory；Numerical simulation

摘要： 为了平衡某水下航行体前后转子的力矩，通过对前后转子进出口速度三角形的分析，提出采用对转式泵喷推进器的设计思路:在后转子叶片后加装导叶，从而保证推进器力矩整体平衡，同时导叶可以起到支撑导管的作用。在反三元设计方法基础上，对前后转子以及导叶之间的速度矩进行简单假设，完成叶片的参数化设计。通过计算流体力学分析，对所设计的泵喷推进器在全附体条件下进行性能计算。结果表明:设计航速下，所设计的泵喷推进器在前后叶片收到功率相差20%的条件下，通过导叶的平衡，推进器整体不平衡力矩缩小到了 1.8N·m，占总力矩的比例从4.6%降为0.4%，完成了航行体推进器力矩的平衡，验证了设计思路和设计方法的有效性。

关键词: 水下航行体；对转式泵喷推进器； 三元设计理论；数值仿真