Innovative Elastomer Transducer Driven by Karman Vortices in Water Flow

Abstract

A simple experimental model of a power generation system was tested in a flowing water tank in order to investigate the performance and feasibility of a small hydroelectric generation system using DE (dielectric elastomer) transducer. The mass of DE material in the power generator module was only 0.1 g. The electric energy generated with a stroke of 10 mm was 12.54 mJ. An electrical energy of approximately 1.5 J per cycle of DE generators can be expected to be generated by scaling up this system, which is capable of being equipped with up to about 100 units of DE transducers. The water velocity was set at 0.30 to 0.70 m/s. This is a small flow, about the same flow as the water in a Japanese garden. This system was driven by Karman vortices in the wake of a cylinder fixed in the water flow. The characteristics of DEs can be utilized to produce electric power effectively. A wing, which is an important part in the generation system to convert fluid energy into mechanical energy, was set behind the cylinder. The wing oscillated due to the pressure caused by Karman vortices, resulting in stretching and contracting of the DE transducers, thus producing electrical power. Experimental results show that an average output power of approximately 31 mW was produced with a generation efficiency of about 66%, when the diameter of the cylinder is 60 mm, the span and chord length of the wing are 120 mm and 30 mm, respectively, the distance between the cylinder and the wing is 170 mm, and the velocity of the water flow is 0.50 m/s.

Possibilities of Artificial Muscles Using Dielectric Elastomers and their Applications

“…Next, regarding the DEG using water flow, it was found that even a fairly slow flow (0.30 m/s to 0.70 m/s.) can sufficiently generate electricity using karma vortices [72]. With this system, it is possible to use the height difference of the water, and it is possible to easily generate power even in waterways beside rice fields.…”

“…The method [72] for generating electricity using vibration is also a useful means, but effective power generation cannot be obtained unless the vibration is large or fast. Research and development of wearable power generation by attaching DEs to humans, robots, and animals is also underway [50].…”

Possibility of a Portable Power Generator Using Dielectric Elastomers and a Charging System for Secondary Batteries

“…Home-sized wind turbines are being studied as a point application for DEGs [37,42,43]. A type using the Kalman style is possible with high efficiency.…”

An Experimental Study on the Motion of Floating Bodies Arranged in Series for Wave Power Generation

“…Chiba et al conducted wave tests using experimental models from 2011 to 2015 in order to investigate the power generation characteristics of buoy type power generation systems equipped with DEs and measured the power generation amounts for various wave heights and wave periods [22][23][24][25][26]. The power generation device using the DE has a simple structure and is lightweight, so that it is expected that the wave power generation system can be simplified, lightened and miniaturized.…”

“…The power generation device using the DE has a simple structure and is lightweight, so that it is expected that the wave power generation system can be simplified, lightened and miniaturized. They also considered aggregates of buoys, arrays of buoys with 3 dimensional multi-story DEs, and the spring constant of the DE in order to realize large power generation system in actual sea areas using the DEs [22][23][24][25][26][27][28].…”