Effect of inlet turbulence intensity on sub-critical vibration
is numerical studied for an elastic cylinder subject to axial
tubular fluid flow. The cylinder is fixed at both ends and is free
to vibrate in any transverse directions. The ANSYS mechanical
APDL+FLUENT two-way system coupling is adopted to
simulate the fluid-structure interaction. The large eddy
simulation model and dynamic model are applied to the
modeling of the turbulent flow and re-meshing, respectively.
The stiffness and flow velocity are combined into the formulae
of the dimensionless flow velocity. The sub-critical vibration of
the single cylinder for different inlet turbulence intensity
(0%~15%) at the sub-critical velocity (3.3) is studied. The
results show that the amplitude of the sub-critical vibration
increases by increasing inlet turbulence intensity. With the
increase of inlet turbulence intensity, the random vibration
occurs. The increasing inlet turbulence intensity is the primary
cause of the random vibration. However, there is no buckling
for higher inlet turbulence intensity at the sub-critical velocity.
With the increasing inlet turbulence intensity, the vibration
mode exhibits the first vacuum beam mode at the first, and then
the high order mode (e.g., the second mode), and again the first
vacuum beam mode at the last.
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.