ABSTRACT
Renewable energy research and its application have been promoted
to slow down climate change and maintain economic growth.
Streamflow or tidal power is valued as a source of energy, and en-
vironmentally friendly and low-friction bearing and sealing systems that employ biomimetic technologies are proposed for its utilisation.
The proposed system is referred to as ‘Bio-Star’, an abbreviation
for Biomimetic System for Tidal power generation learned from Articular cartilage. A dynamo-electric generator and ancillary systems with waterproof construction are installed near or under
water. Lip seals with rotating shaft prevent the ingress of water from
the outside, and excellent frictional properties with various rotation
speeds are required to improve the power generation efficiency
with constantly changing water flow. The Bio-Star was successfully
developed using a hydrated material (polyvinyl formal; PVF) that
mimics articular cartilage in a natural synovial joint. Polyethylene
glycol (PEG) dissolved in distilled water, which is a non-Newtonian
fluid, was used as a lubricant. These materials have low toxicity and
low environmental impact. The biomimetic sealing system exhibits
excellent frictional properties with extremely low ingress of water.
