基于有限元和面元法的弹性螺旋桨流固耦合特性分析

Hydro-elastic analysis for dynamic characteristics of marine propellers using finite element method and panel method

基于三维频域面元和有限元耦合方法建立了螺旋桨双向流固耦合问题的数学模型,推导了螺旋桨双向流固耦合附加质量矩阵以及附加阻尼矩阵,分析了螺旋桨侧斜角以及来流速度对于附加质量矩阵以及附加阻尼矩阵的影响。结果表明,桨盘面来流速度对于附加质量效应影响很小,但对附加阻尼效应影响显著;考虑附加水质量时,螺旋桨侧斜角越大,弹性桨叶第一阶弯曲模态频率下降越多,而第一阶桨叶扭转模态呈现相反规律。研究方法和结果可为低噪声螺旋桨设计提供必要的理论参考。

A mechanical model was built for the double-direction fluid-structure interaction problems of marine propellers by the 3 D frequency domain panel method combined with the finite element method. The added mass and damping matrices due to fluid-structure interaction were derived,and effects of propeller’s skew angle and incoming flow velocity on the two matrices were analyzed. The results showed that the incoming flow velocity significantly affects the added damping matrix,but it has little effect on the added mass matrix; when considering the effect of added mass,the larger the skew angle of propeller,the more the first order bending modal frequency of the propeller drops,while the opposite trend is observed for the first order torsional modal frequency of the propeller. The study methods and results provided a theoretical reference for design of low-noise propellers.