New study shows shark gut design enables valve-free pipes for efficient fluid flow

Pipes designed to enable one-way fluid flow without the use of valves have been developed, taking inspiration from the structure of sharks’ intestines. Researchers at the University of Washington have created a tube with an internal helix that mimics the corkscrew-shaped intestines found in sharks. This design could pave the way for more sustainable fluid transport systems by eliminating the need for conventional valves. The structure of the shark’s intestines, which naturally restricts flow to a single direction, was studied to determine its potential applications in engineering.

The team published their findings in the journal Proceedings of the National Academy of Sciences. The research was led by University of Washington chemist Sarah Keller, who explored whether this biological mechanism could be replicated in synthetic systems. Keller told Science News Explorers how the investigation involved collaboration between experts in physics and materials chemistry to ensure thorough testing and development of the concept.

Rigid and flexible helicopters tested

The research team used 3D printing to create a rigid tube that mimicked the helical structure of shark intestine. The size, angle, and density of the coils in each tube vary. These designs were tested with water flow to assess their efficiency in promoting one-way movement.

According to the report, the tubes with a downward-facing helix allow water to flow two to three times faster than a configuration with an upward orientation. Ido Levin, a physicist involved in the study, explained that the downward configuration mirrors the natural orientation of the shark’s intestines, resulting in optimal flow performance.

The report further states that flexible versions of the tubes were also prepared to observe the effects of deformation on fluid dynamics. Levin said that when the helix was directed downwards into flexible tubes the flow speed increased significantly – up to 15 times faster. Keller said in a statement that the interaction between the tube’s material and the flowing liquid is continuing to be investigated to fully understand this effect.

Future applications considered

Potential applications of this technology are highlighted, particularly in areas where reliability is important. Alshakim Nelson, the team’s materials chemist, indicated in a statement that such valve-free pipes could be useful in drainage systems or air-flow mechanisms, where traditional valves might fail due to wear over time. The absence of moving parts in this design is believed to increase durability and reduce maintenance requirements.

Experts have noted the importance of these findings for both engineering and the understanding of natural systems. The study results emphasize how observations of nature can inspire innovative solutions to common technological challenges. Further exploration is anticipated to determine additional uses for these one-way flow systems.