From Wikipedia, the free encyclopedia
Helical shape with equal rotation and drag in all orientations
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In fluid dynamics, an isotropic helicoid is a shape that is helical, so it rotates as it moves through a fluid, and yet is isotropic, so that its rotation and drag are the same for all orientations of the particle. It was first proposed by Lord Kelvin in 1871, who described a specific geometry with twelve vanes placed around a sphere.[1] As of 2021, such a phenomenon has yet to be proven by researchers.[2]
References
[edit]- ^ William Thomson (1871). "Hydrokinetic solutions and observations". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 42 (281): 362–377. doi:10.1080/14786447108640585. Retrieved 13 October 2021.
- ^ Crane, Leah (16 July 2021). "Strange 3D-printed shapes test 150-year-old mathematical theory". Newscientist.com. New Scientist. Retrieved 10 August 2021.
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