As part of the MIT program I am currently enrolled in, I had to select biomimetic designs inspired by nature and describe their essence, purpose, functionality, and their antecedents in nature. I’ve decided to share portion of the work I have done here.
The essence of the technology in question is the design of the Shinkansen bullet trains in Japan. Introduced in the 1964, these trains were designed for high-speed travel, eventually reaching speeds of 200 miles per hour (about 320 kph). However, they generated significant noise, especially when entering tunnels, due to low-frequency atmospheric pressure waves caused by abrupt changes in air resistance.
To reduce noise and increase efficiency without compromising speed, researchers and engineers turned to nature for inspiration, finding solutions in the kingfisher bird and the owl.
The kingfisher bird is known for its quiet, efficient dive into water to catch fish, thanks to its long, pointed, wedge-shaped beak. The design minimizes splash and noise, keeping the prey unaware.
By adopting a design similar to the kingfisher’s beak for the front of the trains, engineers were able to significantly reduce the pressure waves created as the trains entered tunnels. This redesign resulted in trains that produce 30% less air pressure, use 15% less electricity, and are 10% faster. Additionally, the reduction in air pressure made the trains not only quieter but also more comfortable for
The second inspiration came from the silent flight of owls, particularly their wing’s trailing edge, which alters airflow patterns to reduce noise. This natural stealth mechanism has led to the development of quieter airfoil designs that could revolutionize everyday technologies by significantly reducing noise pollution.
Scientists from Xi’an Jiaotong University in China applied this principle to turbomachinery blades, leading to quieter operation. This research, aiming to address noise pollution from aircraft, vehicles, drones, and wind turbines, was first introduced in a paper published in the journal Physics of Fluid in late 2021. The owl’s wing, renowned for its silent flight, serves as the antecedent in nature for this technology.
By mimicking the design of kingfishers and owls, engineers hope to reduce the environmental impact of noise from machinery, making them more efficient and comfortable.
These interdisciplinary efforts between animal biologists and engineers could lead to a comprehensive understanding of silent flight and its potential applications in reducing noise in human-made technologies.