Numerical simulation of the fluid-structure interaction for an elastic cylinder subjected to tubular fluid flow

摘要

The fluid-structure interaction is numerically studied for an elastic cylinder in a tubular fluid flow. The cylinder is clamped at both ends and is free to vibrate in any transverse directions. The ALE Navier-Stokes equations with large eddy simulation model are applied for the modeling of the turbulent flow and the Euler-Bernoulli beam dynamic equation is solved for the elastic cylinder vibration. The effects of stiffness and flow velocity are formulated into the dimensionless flow velocity, and three cases with different dimensionless velocities are studied. The results show that the dimensionless flow velocity has significant effect on the structure vibration. For small dimensionless flow velocity, the greatly displaced cylinder is damped into the weak oscillation; for larger dimensionless flow velocity, the instability appears and the feature of the flow field alters significantly and the buckling and flutter phenomena are captured. It seems more appropriate to explain the results by the nonlinear theory though the linear theory can predict the instability.