水下螺旋轴流混输泵作为水下增压技术的关键设备，广泛应用于海洋油气田开采中，如何进一步提升其增压性能受到研究人员的关注。本文采用正交试验设计与数值模拟相结合的方法，选取螺旋轴流泵叶轮的5个关键结构参数进行优化，以提高混输泵增压性能。利用Fluent软件、标准SST k-ω湍流模型，对叶轮轴径350mm的螺旋轴流泵单级压缩单元进行数值模拟，研究了叶轮的5个不同结构参数对增压性能的影响，并确定最优的参数组合。结果表明：在流量为500m3/h，转速为4500r/min的工况下，叶片数为3、叶片包角为130°、叶片厚度为6mm、入口安放角和出口安放角为6°的压缩单元增压效果最好，增压达到2.02MPa，相较于初始结构增压提升22%。最后，在不同工况下对优化后的叶轮三级混输泵进行数值模拟，并预测增压效果。研究结果对水下螺旋轴流混输泵的设计及优化提供了理论参考依据。

As a key equipment in underwater pressurization technology， the underwater helical axial flow mixing pump is widely used in the development of offshore oil and gas fields. How to further enhance its pressurization performance has attracted the attention of researchers. This study adopts a method combining orthogonal experimental design and numerical simulation to optimize 5 key structural parameters of the helical axial flow pump impeller， aiming to improve the pressurization performance of the mixing pump. Using Fluent software and the standard SST k-ω turbulence model， numerical simulations are conducted on a singlestage compression unit of a helical axial flow pump with an impeller shaft diameter of 350 mm. The influence of five different structural parameters of the impeller on the pressurization performance is studied， and the optimal parameter combination is determined. The results show that under the operating conditions of a flow rate of 500 m3/h and a speed of 4500 r/min， the pressurization performance is optimal for a compression unit with three blades， a blade wrap angle of 130°， a blade thickness of 6 mm， and inlet and outlet angles of 6°， achieving 2.02 MPa， which is a 22% improvement in pressurization compared to the initial structure. Finally， numerical simulations are carried out on the optimized threestage mixing pump impeller under different operating conditions to predict the pressurization effect. The research results provide a theoretical basis for the design and optimization of underwater helical axial flow mixing pumps.