摘要
[目的]研究弹性螺旋桨在水流中的振动响应特性。[方法]基于CFD/FEM流固耦合方法,利用Work⁃bench平台中的ANSYS-CFX模块对螺旋桨进行双向流固耦合水动力求解,分析弹性螺旋桨变形及应力应变响应特性;考虑到流固耦合对固有特性的影响,利用ACT_Acoustic模块计算桨叶湿模态,结合弹性螺旋桨固有特性和流固耦合水动力结果进行弹性螺旋桨频谱分析。[结果]流固耦合水动力结果相较不考虑流固耦合的定常计算结果更接近试验回归曲线;与干模态相比,弹性螺旋桨前5阶湿模态固有频率减小19%~37%,且四阶和五阶干湿模态振型存在交错情况。频谱分析结果表明,水动力轴向推力和扭矩是弹性螺旋桨在流场中振动响应的主要影响因素,且主要引起弹性螺旋桨的一阶湿模态悬臂振动;桨叶面上,从叶梢处到导边和叶中部分,再到随边部分,最后到叶根处,结构响应逐渐降低。[结论]所做研究可为弹性螺旋桨流固耦合计算分析提供方法途径,也为螺旋桨流固耦合振动噪声分析打下了一定基础。
[Objectives]In the flow field,vibration response characteristics of the elastic propeller are influenced by the interaction of the fluid and structure.[Methods]Based on the CFD/FEM fluid-structure interaction method,ANSYS-CFX modules on the Workbench platform were applied to simulate the tow-way fluid-structure coupling hydrodynamic performance of the elastic propeller and to analyze the deformation and stress-strain response characteristics of the elastic propeller,and the ACT_Acoustic module was used to compute the wet mode of the elastic propeller taking into account of the influence of fluid-structure interaction on the inherent characteristics.The elastic propeller's spectral analysis was carried out to analyze the response characteristics by the results of the hydrodynamic performance and the wet mode.[Results]Compared with the steady uncoupling hydrodynamic results,the fluid-structure coupling hydrodynamic calculations are closer to the open-water test regression formula.The natural frequency of the first fifth order wet mode of the elastic propeller is much lower than the dry modal natural frequency,which decreases by 19%-37%,and the relationship of the fourth and fifth dry-wet modal shapes exchanges.The spectral analysis shows that the hydrodynamic axial thrust and torque are the main influence factors of the structural vibration response in the flow field,and they mainly cause the cantilever vibration of the propeller's first-order wet mode.On one blade,the structural response decreases from the tip to the leading edge and the middle of the blade,and then to the trailing edge,finally to the root.[Conclusions]The study in this paper provides an approach to the fluid-structure interaction simulation of the elastic propeller in the flow field,and also lays the foundation for the analysis on the vibration noise of propeller in terms of the fluid-structure interaction.
作者
谈宇航
彭伟才
TAN Yuhang;PENG Weicai(National Key Laboratory on Ship Vibration and Noise,Wuhan 430064,China;China Ship Development and Design Center,Wuhan 430064,China)
出处
《中国舰船研究》
CSCD
北大核心
2020年第3期102-110,共9页
Chinese Journal of Ship Research
基金
国家自然科学基金资助项目(51609226)。
关键词
螺旋桨
流固耦合
湿模态
频谱分析
propeller
fluid-structure interaction
wet mode
spectral analysis
