Abstract: The influence of the duct on the hydrodynamic characteristics of the propeller has been studied based on the Reynolds-Averaged Navier-Stokes (RANS) method with SST k-ω turbulence model. The numerical simulation is carried out on the design schemes of propellers with or without duct, ducts whether rotate coaxially with the propeller, and ducts with different cross-sectional shapes. The differences in the flow field structure and propeller hydrodynamic characteristics are compared and analyzed. The calculation results show that the duct can reduce the net thrust of the propeller with an increase of the total thrust and a decrease of the torque. The torque increases greatly when the duct rotates coaxially with the propeller. The influence of the cross-sectional shape of the duct on the hydrodynamic characteristics of the propeller mainly concentrates on the cross-section thickness and the trailing edge shrinkage. The thickness change leads to the change of the lines of the leading edge, which greatly affects the net thrust, while the trailing edge shrinkage leads to the changes of the lines of the trailing edge, which has little impact on the thrust but increases the torque. The above results preliminarily indicate the influence of the duct on the hydrodynamic characteristics of the propeller. It can provide references for the subsequent design of the ducted propeller.

Key words: propeller, duct, section thickness, trailing edge shrinkage

摘要： 为探究导管对螺旋桨水动力特性的影响机理,该文基于RANS方法选用SST k-ω湍流模型,对有无导管、导管与螺旋桨是否共轴转动、不同截面形状导管的设计方案进行数值计算,对比分析了不同设计方案下流场结构特征、螺旋桨水动力特性的差异。计算结果表明：导管的存在能够降低螺旋桨净推力而增大总推力,且能够降低扭矩;导管随螺旋桨共同转动,会使扭矩大幅增加;导管的截面形状对螺旋桨水动力特性的影响主要集中在截面厚度和尾缘收缩率上,厚度变化导致前缘段线形变化,对净推力影响较大;尾缘收缩率会导致尾缘段线形变化,对推力影响较小,反而会使扭矩增大。基于以上结果,初步明确了导管对螺旋桨水动力特性的影响规律,为后续导管推进器的设计提供了支撑。

关键词: 螺旋桨, 导管, 截面厚度, 尾缘收缩率