桨径比对串列螺旋桨水动力性能的影响

Effects of Diameter Ratios on Hydrodynamic Performance of Tandem Propellers

关键词:  串列螺旋桨  桨径比  敞水性能  桨间干扰  数值模拟

Key words:  Tandem propellers  Diameter ratio  Open water performance  Blade interaction  Numerical simulation

摘要:

基于B系列和AU系列桨叶参数设计了22只不同桨径比的串列桨，采用数值方法进行性能研究，重点比较了后桨直径大和后桨直径小的串列桨的推力和效率，在此基础上探讨桨径比变化对串列桨性能的影响，最终从流场干扰角度对性能变化的原因进行分析。结果表明：后桨直径大的串列桨的推力和效率均优于后桨直径小的串列桨。在中小进速系数下，随着后桨直径增大，串列桨的效率先增大后减小，存在最佳值，而在大进速系数时，随着前桨径与后桨径比值的减小，效率逐渐提升。较小的前桨对后桨入流的不利干扰减少，是串列桨效率提高的根本原因。

Abstract:

Based on B series and AU series blade parameters， 22 tandem propellers of different diameter ratios were designed， and the hydrodynamic performance of these propellers was investigated by numerical simulation. Then， thrust and efficiency of the tandem propellers with lager aft propellers were compared with the tandem propellers with smaller aft propellers. The influence of diameter ratios on hydrodynamic performance of tandem propellers was investigated. And finally the cause of this influence was analyzed from the perspective of the flow field. Results show that tandem propellers with larger aft propellers have the higher thrust coefficient and efficiency than those with smaller aft propellers. At a low or moderate advance coefficient， the open water efficiency increases and then decreases as the diameter of the aft propeller is enlarged， which means there exists optimum efficiency. At a high advance coefficient， efficiency keeps growing as the ratio of the forward propeller diameter to the aft propeller diameter （D_f /D_a） increases. A root cause of the improvement in efficiency is that the interaction between the forward propeller and the aft propeller is weakened as the diameter of the forward propeller is reduced.