轮缘推进器水动力性能影响因素数值研究

Numerical Research of Hydrodynamic Performance Impact Factors of Rim-driven Thruster

为指导轮缘推进器(RDT)水动力学设计,借助CFD方法,对RDT各主要几何特征对其水动力性能影响开展研究。首先,验证CFD数值方法分析RDT水动力特性的有效性;然后,基于CFD研究RDT水动力性能的各主要影响因素,主要包括导管的长径比、扩散比、导管收缩比和桨叶梢径比。结果表明:RDT最佳长径比随载荷系数递增,并趋于一极限值,相比于导管扩散比和收缩比,导管长径比因素更能主导RDT的设计优化;RDT最佳扩散比随载荷系数递减,并趋于一极限值,最佳扩散比随长径比递减;RDT的收缩比对水动力性能影响不及扩散比和长径比显著,最佳收缩比随载荷系数呈线性递增,随长径比递减;RDT的最佳梢径比随载荷系数递增,无毂RDT比有毂RDT具有更小的最优梢径比。研究结果可为轮缘推进器的水动力学设计和优化提供参考。

In order to guide the hydrodynamic design of rim thruster(RDT), the influence of main geometric characteristics of RDT on its hydrodynamic performance is studied by using CFD method. Firstly, the effectiveness of CFD numerical method to analyze the hydrodynamic characteristics of RDT is verified. Secondly, the main influencing factors of RDT hydrodynamic performance are studied based on CFD, including the aspect ratio of duct, diffusion ratio, contraction ratio of duct and tip diameter ratio of blade. The results show that the optimal length diameter ratio of RDT increases with the load factor and tends to a limit value. Compared with the diffusion ratio and contraction ratio of the tube, the length diameter ratio of the pipe can dominate the design optimization of the RDT;the optimal diffusion ratio of the RDT decreases with the load coefficient and tends to a limit value, and the optimal diffusion ratio decreases with the length diameter ratio;the influence of the contraction ratio of RDT on the hydrodynamic performance is less significant than that of the diffusion ratio and the length diameter ratio. The optimal tip diameter ratio of RDT increases linearly with the load factor and decreases with the length diameter ratio;the optimal tip diameter ratio of RDT increases with the load factor, and the hub free RDT has a smaller optimal tip diameter ratio than the hub RDT. The research results can provide a reference for the hydrodynamic design and optimization of the rim thruster.