Fluid flow nozzle energy harvesters

Abstract

Power generation schemes that could be used downhole in an oil well to produce about 1 Watt average power with long-life (decades) are actively being developed. A variety of proposed energy harvesting schemes could be used to extract energy from this environment but each of these has their own limitations that limit their practical use. Since vibrating piezoelectric structures are solid state and can be driven below their fatigue limit, harvesters based on these structures are capable of operating for very long lifetimes (decades); thereby, possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. An initial survey [1] identified that spline nozzle configurations can be used to excite a vibrating piezoelectric structure in such a way as to convert the abundant flow energy into useful amounts of electrical power. This paper presents current flow energy harvesting designs and experimental results of specific spline nozzle/ bimorph design configurations which have generated suitable power per nozzle at or above well production analogous flow rates. Theoretical models for non-dimensional analysis and constitutive electromechanical model are also presented in this paper to optimize the flow harvesting system.

Piezoelectric Energy Harvesting in Internal Fluid Flow

“…These include vortex shedding [ 8 , 9 , 10 , 11 , 12 ], flapping motions [ 13 ], hydraulic pressure [ 14 ], and impeller structures [ 15 , 16 ]. The approach we are investigating consists of a cantilever mounted in an internal flow channel where either the cantilever itself is a piezoelectric bimorph, or a non-piezoelectric cantilever drives a transducer [ 17 , 18 ]. The internal flow passage is a spline-shaped nozzle-diffuser.…”

Modeling and simulation of a fluttering cantilever in channel flow

“…The geometry illustrated in figure 1a and dimensional parameters in table 1 are inspired by the flow energy harvester configurations in (Sherrit et al, 2014(Sherrit et al, , 2015. We consider the beam displacement as the output of a system defined by a characteristic velocity (or flow rate), geometrical parameters, and material properties, for a total of 10 possible nondimensional groups that determine its dynamics.…”

“…Applications include wind instruments (Sommerfeldt & Strong, 1988;Backus, 1963), human snoring (Balint & Lucey, 2005;Tetlow & Lucey, 2009), vocalization (Tian et al, 2014), and enhanced heat transfer (Shoele & Mittal, 2016;Hidalgo et al, 2015). Recently, this geometry has also been used for flow-energy harvesting, with devices specifically targeting power generation for remote sensor networks (Sherrit et al, 2014(Sherrit et al, , 2015Lee et al, 2015Lee et al, , 2016. For most of these applications, the flutter instability boundary is the essential result sought, as the functional requirements of engineering designs (i.e.…”

Design and experimental evaluation of flextensional-cantilever based piezoelectric transducers for flow energy harvesting

“…Aeroelastic flutter, in particular, has been shown as an effective fluid-structure coupling mechanism when bimorph-type actuators have relatively low resonant frequencies (less than 300 Hz). Yet a major drawback is their brittle nature when exposed to large deformation, resulting in short lifetimes [5,6].…”