Abstract Analysis of flexible marine propellers in terms of their structural response and stress is the key to accurate fatigue prediction. At present, finite element method (FEM) analyses of flexible propellers have been performed as a part of the fluid–structure interaction (FSI) analysis using a numerical method for the flexible structures, which is identical to that used for their rigid counterparts. In this study, the Euler force in a rotating frame is employed as an additional external force on the blades of the marine propeller during the FSI analysis. The Euler force is an inertial force component in the rotating frame due to angular acceleration. Acceleration of the rotating frame arises from large deformations of the propeller due to its flexible characteristics. The angular acceleration of the propeller is obtained for each time step, and the resulting Euler force is accounted for as a body force. The FSI analysis results are compared to experimental results in terms of the structural response, stress, and fatigue. It is clear that the Euler force has a major effect on the fatigue characteristics of the propeller because it amplifies the main response components. In conclusion, incorporating the Euler force in FSI analyses of flexible marine propellers is necessary for adequate prediction of the propeller fatigue.

中文翻译：

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考虑旋转框架中欧拉力的 FSI 分析柔性船用螺旋桨的疲劳预测

摘要 柔性船用螺旋桨的结构响应和应力分析是准确预测疲劳的关键。目前，柔性螺旋桨的有限元法 (FEM) 分析已作为流固耦合 (FSI) 分析的一部分，使用柔性结构的数值方法进行，这与用于刚性结构的数值方法相同。在这项研究中，在 FSI 分析过程中，旋转框架中的欧拉力被用作船用螺旋桨叶片上的附加外力。欧拉力是旋转坐标系中由于角加速度引起的惯性力分量。由于螺旋桨的柔性特性，螺旋桨的大变形会引起旋转框架的加速。获得每个时间步长的螺旋桨角加速度，并且由此产生的欧拉力被视为体力。FSI 分析结果与实验结果在结构响应、应力和疲劳方面进行了比较。很明显，欧拉力对螺旋桨的疲劳特性有主要影响，因为它放大了主要的响应分量。总之，在柔性船用螺旋桨的 FSI 分析中加入欧拉力对于充分预测螺旋桨疲劳是必要的。