A low-dimensional model of a top-tensioned riser under excitations from vortices and time-varying tension is proposed, where the van der Pol wake oscillator used to simulate loading caused by vortex shedding. The governing partial differential equations describing fluid–structure interactions are formulated multi-mode approximations obtained using Galerkin projection method. one mode approximat...

Vortex-induced vibration (VIV) is a highly nonlinear fluid-structure interaction (FSI) phenomenon, and its accurate prediction remains challenging. In this study, we developed high-order partitioned FSI framework towards simulation of the VIV phenomenon. The focus on simulating two-way coupled between flexibly mounted rigid body surrounding fluids. framework, computational fluid dynamics method...

Under the actions of ocean currents and/or waves, deep-sea flexible risers are often subject to vortex-induced vibration (VIV). The VIV can lead severe fatigue and structural safety issues caused by oscillatory periodic stress large-amplitude displacement. As have natural modes with lower frequency higher density, a multimode is likely occur in under action currents, which considered as shear f...

Numerical simulations are carried out to investigate the vortex-induced vibrations of a two-degree-of-freedom (2DOF) near-wall rotating cylinder. Considering effects gap ratio, reduced velocity and rotational rate, amplitude response, wake variations fluid forces analyzed, with Reynolds number 200 mass ratio set 1.6. The correlative mechanism in wake–hydrodynamics–vibration is revealed. results...

1 Lagrangian analysis is capable of revealing the underlying structure and complex phenomena in unsteady flows. We present Particle-Image Velocimetry measurements of the wake of a cylinder undergoing streamwise vortex-induced vibrations and calculate the Finite-Time Lyapunov Exponents (FTLE) in backward-and forward-time. The FTLE fields are compared to the phase-averaged vorticity fields for th...

Multiphase vortices are widely present in the metallurgical pouring processes, chemical material extraction, hydroelectric power plant energy conversion, and other engineering fields. Its critical state detection is of great significance improving product yield resource utilization. However, multiphase vortex a complex dynamics problem with highly nonlinear features, its fluid-induced vibration...

The Active Vibration and Noise Reduction (AVINOR) aeroelastic simulation code for helicopter rotor blades is described. AVINOR is a research code that has been developed at UCLA and the University of Michigan for the purpose of conducting computationally efficient aeroelastic response analyses while maintaining a level of fidelity so as to be suitable for preliminary design of helicopter rotor ...