摘要
以Ansys Fluent为平台,对二维两自由度偏心桥梁断面风致振动进行数值模拟研究。将Newmark-β法编程嵌入UDF,在每一时间步上求解微分方程得到并更新物理量的方式实现自由振动流固耦合。与非偏心桥梁节段模型相比,偏心节段模型动力学方程式左右两边分别耦合,利用Newmark-β法求解矩阵形式的偏心两自由度动力学方程组并输入简谐荷载进行调试,对比数值解和解析解证明程序正确性。非偏心节段模型数值模拟颤振临界风速与其他学者实验得到的颤振临界风速高度一致,通过此模拟方法进一步模拟偏心对桥梁节段模型的颤振稳定性提高效果。通过风洞试验验证了数值模拟的可靠性。
Taking the finite element(FE)software Ansys Fluent as a platform,wind-induced vibration of a 2-D 2-DOF eccentric bridge deck section was studied.Newmark-βmethod was embedded into user defined functions(UDF),and free vibration considering fluid-structure interaction was realized by solving the corresponding differential equations and updating the corresponding physical quantities in each time step.Compared with a non-eccentric bridge segment model,both left and right sides of dynamic equation for an eccentric bridge segment model have coupled terms.Newmark-βmethod was used to solve the eccentric 2-DOF dynamic equation set and simple harmonic loads were input for debugging.Numerical solution was compared with the analytical one to verify the correctness of the simulation procedure.It was shown that the numerical simulation value of flutter critical wind speed for the non-eccentric bridge segment model agrees well with the test value obtained by other researchers.The proposed simulation method was used to further simulate effects of eccentricity on the flutter stability of the bridge segment model to improve the method’s effect,and wind tunnel tests were used to verify the reliability of numerical simulation.
作者
贾杰
韩荣轩
JIA Jie;HAN Rongxuan(College of Civil Engineering,Northeast Forestry University,Harbin 150040,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2020年第17期203-209,共7页
Journal of Vibration and Shock
基金
中央高校科学前沿与交叉学科创新基金项目(2572015CB31)。
关键词
流固耦合
数值模拟
偏心桥梁断面
动网格
计算流体动力学(CFD)
颤振
fluid-structure interaction
numerical simulation
eccentric bridge section
dynamic mesh
computational fluid dynamics(CFD)
flutter
