水下机器人螺旋桨的设计与仿真分析

Design and Simulation Analysis of Underwater Robot Propeller

推进器是水下机器人的动力装置,螺旋桨是水下推进器的重要组成部分。为了设计出一套高性能的螺旋桨,首先基于图谱法对磁耦合螺旋桨进行了理论设计,确定了螺旋桨的各项结构参数,完成了螺旋桨的初步设计方案;其次基于流体力学的方法,利用Fluent软件对螺旋桨进行了模拟计算和仿真分析。分析结果表明:螺距比的选择受到工作时的进速系数和螺旋桨的推力系数共同制约,在保证螺旋桨推力系数达到要求的前提下,进速系数越小,螺距比选小值;盘面比大小不影响桨叶面上的推力,所以螺旋桨效率很接近,当高进速系数时,单位桨叶面提供的推力相等,盘面比大的螺旋桨可以吸收更多的主机功率,效率更高;螺旋桨外缘与导管内径间隙越小,螺旋桨的推进系数越大,导管螺旋桨效率最高;随着收缩系数的改变,在某些进速系数下导管螺旋桨推力系数稍微有些波动,总体大小基本不变,但是收缩系数不可以过大;如果载荷较大,则取较小的扩张系数;如果载荷较小,则取较大的扩张系数。研究结果对水下机器人螺旋浆的进一步优化设计有一定的参考作用。

The thruster is the power unit of the underwater robot,and the propeller is an important part of the underwater thruster. In order to design a set of high-performance propellers,the theoretical design of the magnetically coupled propellers was first conducted based on the graph method. The structural parameters of the propellers were initially determined,and the preliminary design of the propellers was completed. The simulation calculation and analysis on the propeller were conducted using Fluent based on hydromechanics. The analysis results show that the selection of the pitch ratio is influenced by the advance coefficients and the propeller thrust coefficient. Under the premise of ensuring that the propeller thrust coefficient meets the requirements,lower advance coefficients leads to a smaller pitch ratio. Disk ratio has no effects on the thrust on the blade surface,resulting in very close of propeller efficiencies. Under high advance coefficients,the thrust provided by the unit blade surface is equal. The propeller with a larger disk ratio can absorb more main engine power and be more efficient. Smaller gap between the outer edge of the propeller and the inner diameter of the guide pipe leads to larger propeller coefficient,and the guide pipe propeller’s efficiency will be the highest. The guide pipe propeller thrust coefficient fluctuates slightly under certain advance coefficients with the change of the shrinkage coefficient. The shrinkage factor should not be too large. If the load is large,a smaller expansion coefficient is preferred. If the load is small,a larger expansion coefficient is better. The study results could provide references for the further optimization design of the underwater robot propeller.