VIVACE (Vortex Induced Vibration Aquatic Clean Energy): A New Concept in Generation of Clean and Renewable Energy From Fluid Flow

Abstract

Any device aiming to harness the abundant clean and renewable energy from ocean and other water resources in the USA must have high energy density, be unobtrusive, have low maintenance, be robust, meet life cycle cost targets, and have a 10–20 year life. The VIVACE (Vortex Induced Vibration Aquatic Clean Energy) Converter — invented by Bernitsas & Raghavan and patented through the University of Michigan — satisfies those criteria. It converts ocean/river current kinetic energy to electricity using VIV successfully and efficiently for the first time. VIVACE is based on the simple idea of maximizing rather than spoiling vortex shedding and exploiting rather than suppressing VIV. It introduces optimal damping for energy conversion while maintaining VIV over a broad range of vortex shedding synchronization. VIV occurs over very broad ranges of Reynolds (Re) number. Only two transition regions suppress VIV. Thus, even from currents as slow as 0.25m/sec, VIVACE can extract energy with high efficiency making ocean/river current energy a more accessible and economically viable resource. In this paper, the underlying concepts of the VIVACE Converter are discussed. The designs of the physical model and lab prototype are presented. A mathematical model is developed and design particulars for a wide range of application scales are calculated. Experimental measurements on the lab prototype are reported in the sequel paper and used here for preliminary benchmarking.