基于重叠网格技术柔性旗帜与流体耦合运动数值模拟  

Numerical Simulation of Flexible Flag-Fluid Coupled Motion Based on Overlapping Grid Technique

作　　者：杜小振[1] 郭东兴 王文秀 韩艺 刘晓彤 王淑珺 DU Xiao-zhen;GUO Dong-xing;WANG Wen-xiu;HAN Yi;LIU Xiao-tong;WANG Shu-jun(College of Mechanical and Electronic Engineering,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]山东科技大学机械电子工程学院,青岛266590

出　　处：《科学技术与工程》2025年第2期473-483,共11页Science Technology and Engineering

基　　金：山东省自然科学基金(ZR2021ME111)。

摘　　要：为研究分析自然界与风能采集领域中柔性旗帜与空气流固耦合运动特性,基于空气动力学原理和二维柔性板轴向不可拉伸假设推导旗帜颤振非线性理论模型,研究了旗帜与空气之间的耦合运动,分析长度、质量比和风速对其运动特性影响。利用双向流固耦合方法及重叠网格技术对旗帜随风摆动过程进行数值模拟,得出流场中旗帜运动行为及周围流场特性。结果表明:临界颤振风速随旗长增加而减小,摆动位移随风速增加先增大后减小;质量比越大,颤振频率越小,斯特劳哈尔数受其影响较小;旗帜尺寸一定时,风速较小,摆动位移、频率较小,风速超过临界颤振风速发生大幅度颤振现象;旗帜周围漩涡会经历产生、脱落和消失过程,周围压力及速度会随漩涡运动过程发生变化。可见采用基于重叠网格技术的数值模拟方法可有效解决柔性旗帜大变形问题,实现理论与数值仿真验证分析。Aerodynamic principles and the assumption of axial inextensibility of a two-dimensional flexible plate were used to derive a nonlinear theoretical model of flag flutter,investigate and analyze the coupled motion characteristics of flexible flag and airflow in nature and wind energy collection fields,and examine the effects of length,mass ratio,and wind speed on its motion characteristics.The flag oscillation process in the wind was numerically simulated using the bidirectional fluid-structure coupling method and the overlapping mesh methodology,from which the features of the surrounding flow field and the motion behavior of the flag inside it were determined.The findings indicate that while swing displacement increases and subsequently declines with wind speed,the crucial flutter wind speed lowers as flag length increases.The chirp frequency decreases as the mass ratio increases,and the Strahl number is less affected.With the predefined dimensions of the flag,at low wind speeds,both the displacement and frequency of the swing are low.However,when the wind speed exceeds the critical vibration threshold,a significant vibration phenomenon occurs.Changes in surrounding pressure and velocity are caused by the flag-encircling vortex as it progresses through phases of formation,shedding,and disappearing.Numerical simulation techniques based on the overlapping mesh methodology successfully address the deformation problem of flexible flags.Theoretical and numerical simulations can be verified and analyzed with this method.

关 键 词：柔性旗帜 流固耦合 重叠网格 流场 数值模拟 

分 类 号：O351.2[理学—流体力学]