基于CFD技术的螺旋桨非定常流场数值模拟

针对单独螺旋桨模型，基于动态结构网格搭接技术，采用CFD方法对其非定常流场进行了数值模拟。首先针对全部外形生成多块点搭接和面搭接两套计算网格，通过分析两套网格的计算结果，验证动态网格搭接技术的可行性和正确性，得出螺旋桨性能参数随转速的变化规律；在此基础上分析了雷诺平均NS(RANS)方程和Euler方程的数值模拟结果；最后研究了攻角对单独螺旋桨性能参数的影响。研究结果表明：动态网格搭接技术能够很好地模拟非定常螺旋桨的性能参数；螺旋桨的拉力系数和功率系数都随着转速的增加而增大；对螺旋桨非定常流场进行数值模拟时，采用Euler方程就能够满足工程精度的需求；攻角0度时单片桨叶的拉力系数和转矩系数都是恒值，而在攻角10度时却都呈现出周期性的正弦曲线。

Numerical simulation of unsteady flow around propeller based on CFD technology

CFD technology was applied to do the numerical simulation of unsteady flow around the single propeller model, which was based on the structured dynamic grids. To start with, two sets of calculation grids consisting of multi-block point-to-point and face-to-face patched grid were created in terms of the whole shape. Then through the contrastive analysis of the computational results, the feasibility and accuracy of dynamic patched grids were verified. At the same time, the regular patterns in which propeller performance parameters varied in accordance with the rotation rate were obtained. Numerical simulation results of Reynolds-Averaged Navier-Stokes (RANS) equations and Euler equations were analyzed based on the research above. In the end, made a study of the influence of angles. The results show that dynamic patched grids are efficient to simulate the characteristic parameters of the unsteady flow. The thrust and power cofficients increase considerably with the rise of the rotational speeds. Euler equations are qualified for engineering precision requirement in the numerical simulation of unsteady flow around single propeller. The thrust and torque cofficients are contant when the angle is 0 degree and take on sinusoidal vibration when 10 degree.