Vortex-induced vibrations (VIV) of porous objects ‒ LFMI ‐ EPFL

Project type: Master project

Description: VIV is an example of fluid-structure interaction. Large-amplitude oscillations can arise from a coupling between the solid motion and vortex shedding in the fluid wake (Fig. 2). VIV should be either avoided (for ex. when vibrations are detrimental to the mechanical integrity of structures like bridges (Fig. 1) and chimneys), or enhanced in energy-harvesting systems.

This project aims at analyzing the effect of the object porosity on VIV (Fig. 3). The student will use numerical simulations and a recent porosity model to study the linear stability and nonlinear dynamics of the coupled fluid-solid system, and explore the effect of parameters (ratio of fluid-solid densities, ratio of fluid-solid natural frequencies, Reynolds number, porosity properties, etc.).

Fig. 1 Wind-induced collapse of the Tacoma Narrows bridge, 1940.

Fig. 2 VIV model (spring-mounted cylinder in a fluid flow) and vortex shedding during large-amplitude VIV.

Fig. 3 Examples of permeable cylindrical shells.

Supervisor: Edouard Boujo