Asymmetric fluid flow in helical pipes inspired by shark intestines

Unlike human intestines, which are long, hollow tubes, the intestines of sharks and rays contain interior helical structures surrounding a cylindrical hole. One function of these structures may be to create asymmetric flow, favoring passage of fluid down the digestive tract, from anterior to posterior. Here, we design and 3D print biomimetic models of shark intestines, in both rigid and deformable materials. We use the rigid models to test which physical parameters of the interior helices (the pitch, the hole radius, the tilt angle, and the number of turns) yield the largest flow asymmetries. These asymmetries exceed those of traditional Tesla valves, structures specifically designed to create flow asymmetry without any moving parts. When we print the biomimetic models in elastomeric materials so that flow can couple to the structure’s shape, flow asymmetry is significantly amplified; it is 7-fold larger in deformable structures than in rigid structures. Last, we 3D-print deformable ver..., , , # Asymmetric fluid flow in helical pipes inspired by shark intestines

[https://doi.org/10.5061/dryad.4j0zpc8mt](https://doi.org/10.5061/dryad.4j0zpc8mt)

This dataset supplements our paper \"Asymmetric fluid flow in helical pipes inspired by shark intestines\", and includes all the results needed to support our conclusions.
It contains all 3D structures (in STL format) of the helical pipes used in the paper and all our measurements of their hydraulic properties (in CSV format).

## Description of the data and file structure

**STL files:**

* **Biomimetic helical pipes**: The filename of each STL file is formatted as \"SimplifiedModel_*[Rigid/Soft]*_p[pitch values]*_rHole*[hole radius]*_a*[angle tangent]*_nTurn]*.STL\".
Note that Rigid / Soft models are identical, and this tag was added to indicate the soft (deformable) pipes used in this study.
There are a total of 26 rigid pipe models and 4 soft pipe models.
* **Deformed helical pipes**: the deformed inner helical membranes (under a ...