Hydrokinetic Energy Conversion Using a Single-Cylinder Nonlinear Oscillator in Flow Induced Oscillations

Abstract

In 2006, the Marine Renewable Energy Laboratory of the University of Michigan introduced a new concept for horizontal Marine Hydrokinetic (MHK) energy conversion using alternating-lift. The Converter, nicknamed VIVACE, utilizes alternating-lift based on cylinders on elastic support responding in FIO (Flow Induced Oscillations) and particularly Vortex Induced Vibrations (VIV), galloping, and their coexistence. Over a decade of research using 1–4 oscillators in tandem and staggered arrangements, with smooth and rough cylinders, and linear and nonlinear springs and dampers have produced a power envelope showing high power-to-volume density and efficiency in MHK energy conversion as well as slow-flow onset. This paper focuses on: (i) Single-cylinder Converter. (ii) Various nonlinear oscillator models with displacement-adaptive stiffness and velocity-adaptive damping. (iii) Systematic variation of parameters for energy harnessing. (iv) Identifying flow domains where each nonlinear effect enhances MHK energy conversion. Experiments were conducted for 20,000 < Re < 120,000, a subset of the TrSL3 flow regime.