Turbulence Intensity Effect on Axial-Flow-Induced Cylinder Vibration

Abstract

A numerical study is conducted on the effect of inlet turbulent intensity on the axial-flow-induced vibration of an elastic cylinder subjected to axial tubular flow. The cylinder with fix-supported ends is free to vibrate in the lateral direction. While a large eddy simulation is used to calculate the turbulent flow field, the Ansys mechanical + Fluent two-way coupling has been deployed to capture the fluid-structure interaction. The calculation agrees qualitatively with experimental data. Various inlet turbulence intensities, T u , i.e., 0, 0.3, 5.0 and 10.0%, are examined at two non-dimensional flow velocities, \( \overline{U} \), i.e., 3.30 and 7.62. The results show that T u has a significant effect on the cylinder vibration. At \( \overline{U} \) = 3.30, the maximum displacement grows with T u and the vibration is classified as the subcritical vibration; the instability of cylinder is not induced with increasing T u . At \( \overline{U} \) = 7.62, the buckling occurs at T u = 0%, while the flutter takes place at T u = 0.3%; both are associated with an asymmetric pressure distribution around the cylinder.