Energy harvesting from transverse galloping

Abstract

ARTICLE INFO ABSTRACTSome elastic bluff bodies under the action of a fluid flow can experience transverse galloping and lose stability if the flow velocity exceeds a critical value. For flow velocities higher than this critical value, there is an energy transfer from the flow to the body and the body develops an oscillatory motion. Usually, it is considered as an undesirable effect for civil or marine structures but here we will show that if the vibration is substantial, it can be used to extract useful energy from the surrounding flow. This paper explores analytically the potential use of transverse galloping in order to obtain energy. To this end, transverse galloping is described by a one-degree-offreedom model where fluid forces obey the quasi-steady hypothesis. The influence of cross-section geometry and mechanical properties in the energy conversion factor is investigated.

Optimal electromagnetic energy extraction from transverse galloping

“…(6), is presented in the same way as in Barrero-Gil et al (2010), or Grouthier et al (2013), where the power harvested is compared to the power available in the flow in a section equivalent to the diameter of the prism. However, other ways of defining such an efficiency are possible.…”

“…In recent years, Flow-Induced Vibrations like Vortex-induced Vibrations (VIV), Transverse Galloping (TG) oscillations or Flutter have been considered as a new mean to harvest energy from fluid flows (Bernitsas et al, 2008;Barrero-Gil et al, 2010Sanchez-Sanz et al, 2009;Grouthier et al, 2013;Abdelkefi et al, 2013;Doare and Michelin, 2011;Allen and Smits, 2001, to name only a few). The basic idea is to take advantage of these phenomena to convert part of the kinetic energy of the flow into oscillatory mechanical energy of the elastic body; thereafter, the mechanical energy of the body may be converted into electrical energy by electromagnetic, piezoelectric, or electrostatic means.…”

“…TG potential for energy harvesting has been recently investigated theoretically, numerically, and experimentally by Barrero-Gil et al (2010), co-workers (2012, 2013), Sirohi andMahadik (2011), or Zhao et al (2012). Briefly outlined, it can be said that TG is a fluid-elastic instability that appears in some elastic bluff bodies when the velocity of the incident flow exceeds a critical value.…”

“…For an authoritative introduction to TG phenomenology and modelling, the reader is referred to Parkinson (1989), or the books by Blevins (1990), Naudascher andRockwell (1994), or Pai'doussis et al (2011). Barrero-Gil et al (2010) developed a theoretical model to study TG potential for energy harvesting. They considered a one degree of freedom model to describe galloping oscillations and a quasi-steady approximation to describe TG fluid forces.…”

“…Here, a forward step is presented in order to model the TG dynamics when an electromagnetic generator is used to produce electrical current which is dissipated at a generic electrical load resistance. To this end, the model presented at Barrero-Gil et al (2010) is now coupled with a mathematical model of the electromagnetic generator.…”