CASO DE ESTUDIO
Enhanced VIV Energy Harvesting with OAV Air Bearings and a Smart Damper–Spring System
Efficient energy harvesting from natural fluid flows like wind and marine currents have historically been and continues to be exceedingly difficult. One common effect of fluid motion is vortex-induced vibrations (VIV), which offers an opportunity to convert these vibrations into usable energy. This case study explores how integrating a virtual damper–spring system paired with OAV Air Bearings enhances VIV energy harvesting by addressing critical challenges such as minimizing energy loss, enhancing adaptability, and increasing long term durability.
Traditional VIV systems rely on physical dampers and springs. They suffer from inefficiency due to energy loss from friction and poor damping control, and have limited adaptability to varying flow conditions, which restricts their optimal performance. Moreover, mechanical components in traditional systems experience extensive degradation in fluid environments, resulting in reduced efficiency and high maintenance costs.
To overcome these challenges, the research team at the University of Poitiers in France developed a virtual damper–spring system that adjusts damping and stiffness in real time through software designed to allow for seamless adaptation to changing flow conditions without the need for physical modifications. Such a system requires ultra precise controls that eliminate friction, enhance stability, and ensures reliable alignment in harsh environments. OAV Air Bearings are ideally suited for this role, offering frictionless motion, increased system stability, and improved alignment. The resulting experiments indicated a much enhanced energy capture and extended lifespan of the system.
Figure 1: Setup of the virtual damper-spring system with the frictionless OAV Air Bearing for the experiment
OAV Air Bearings are ideally suited for this application, offering advantages that directly address the limitations of traditional VIV systems. By providing frictionless motion, OAV Air Bearings reduce energy loss, enabling quick responsiveness to changes in flow speed and maximizing energy capture. Precision alignment enables the virtual damper–spring system to operate with high accuracy. Additionally, with no contact or rolling parts, OAV Air Bearings smooth low vibration performance operate with no noise, no wear and tear, and require no maintenance especially for fluid-exposed systems that need durability.
Experiments showed that maintaining stable performance across a range of flow rates significantly increased energy yield. With OAV Air Bearings, the system would benefit from longer life, more reliable alignment, and reduced noise from vibrations. The ability to resist environmental wear (from wind or marine forces, for example) without performance loss gives OAV Air Bearings a clear advantage over traditional bearing solutions in these settings.
The virtual damper–spring system explored in this study has strong potential to transform VIV energy harvesting by offering a highly adaptable and efficient design. When paired with OAV Air Bearings, the system gains precision, reliability, and longevity, making it suitable for prolonged use in demanding real-world applications, especially in the marine renewable energy industry where reliability and low maintenance costs are crucial.
This combined approach could be especially beneficial in industries like marine renewable energy, where reliability and low maintenance are crucial. By reducing operational costs and extending system life, integrating OAV Air Bearings could substantially increase the return on investment for VIV-based energy harvesting solutions.
Figure 2: Photography of the experimental setup
Figure 3: Graph one shows variations in reduced amplitude (A*10) as a function of reduced velocity (U*) for the three configurations analysed. Graph two shows variations in reduced amplitude (A*10) as a function of reduced velocity (U*) for different values of damping ratios. Graph three shows variations in energy harvesting efficiency (in percent) as a function of the reduced velocity.
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Schmider, A., Kerhervé, F., Spohn, A., and Cordier, L., “Improved VIV energy harvesting with a virtual damper–spring system,” Ocean Engineering, vol. 293, p. 116668, 2024. doi: 10.1016/j.oceaneng.2024.116668.
This material is based on work supported by the University of Poitiers Health, Safety and Environment Department.