Nature has found ways to laminarize turbulent flows, as demonstrated by the high swim speed of dolphins and the silent flight of owls. Owls locate their prey by hearing and need to fly silently. In both cases it has something to do with the soft pliable surface of the moving body and the wavy pattern that occurs on the dolphin skin and the owl feathers. Our objective was to investigate whether a pipe lined with a hairy soft carpet would “laminarize” air flows. The degree of laminarization was determined by the velocity profile. Manual pressure measurements were done to determine the air velocity at cross-sections along the pipe. Varying flow rates were tested before the hair was cut increasingly shorter. It was found that for some hair lengths the velocity profile approached the parabolic form of laminar flow at very high Reynolds number.
Published in | International Journal of Mechanical Engineering and Applications (Volume 3, Issue 4) |
DOI | 10.11648/j.ijmea.20150304.13 |
Page(s) | 63-70 |
Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
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Copyright © The Author(s), 2015. Published by Science Publishing Group |
Flows in Pipes and Nozzles, High-Reynolds-number Turbulence, Interactions with Surfaces, Laboratory Studies, Laminarization, Stability of Laminar Flows, Velocity Measurements
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APA Style
Bo Anders Nordell, Ragnar Oskar Gawelin. (2015). Highly Turbulent Flow Laminarized by Hairy Pipe Walls. International Journal of Mechanical Engineering and Applications, 3(4), 63-70. https://doi.org/10.11648/j.ijmea.20150304.13
ACS Style
Bo Anders Nordell; Ragnar Oskar Gawelin. Highly Turbulent Flow Laminarized by Hairy Pipe Walls. Int. J. Mech. Eng. Appl. 2015, 3(4), 63-70. doi: 10.11648/j.ijmea.20150304.13
AMA Style
Bo Anders Nordell, Ragnar Oskar Gawelin. Highly Turbulent Flow Laminarized by Hairy Pipe Walls. Int J Mech Eng Appl. 2015;3(4):63-70. doi: 10.11648/j.ijmea.20150304.13
@article{10.11648/j.ijmea.20150304.13, author = {Bo Anders Nordell and Ragnar Oskar Gawelin}, title = {Highly Turbulent Flow Laminarized by Hairy Pipe Walls}, journal = {International Journal of Mechanical Engineering and Applications}, volume = {3}, number = {4}, pages = {63-70}, doi = {10.11648/j.ijmea.20150304.13}, url = {https://doi.org/10.11648/j.ijmea.20150304.13}, eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmea.20150304.13}, abstract = {Nature has found ways to laminarize turbulent flows, as demonstrated by the high swim speed of dolphins and the silent flight of owls. Owls locate their prey by hearing and need to fly silently. In both cases it has something to do with the soft pliable surface of the moving body and the wavy pattern that occurs on the dolphin skin and the owl feathers. Our objective was to investigate whether a pipe lined with a hairy soft carpet would “laminarize” air flows. The degree of laminarization was determined by the velocity profile. Manual pressure measurements were done to determine the air velocity at cross-sections along the pipe. Varying flow rates were tested before the hair was cut increasingly shorter. It was found that for some hair lengths the velocity profile approached the parabolic form of laminar flow at very high Reynolds number.}, year = {2015} }
TY - JOUR T1 - Highly Turbulent Flow Laminarized by Hairy Pipe Walls AU - Bo Anders Nordell AU - Ragnar Oskar Gawelin Y1 - 2015/07/28 PY - 2015 N1 - https://doi.org/10.11648/j.ijmea.20150304.13 DO - 10.11648/j.ijmea.20150304.13 T2 - International Journal of Mechanical Engineering and Applications JF - International Journal of Mechanical Engineering and Applications JO - International Journal of Mechanical Engineering and Applications SP - 63 EP - 70 PB - Science Publishing Group SN - 2330-0248 UR - https://doi.org/10.11648/j.ijmea.20150304.13 AB - Nature has found ways to laminarize turbulent flows, as demonstrated by the high swim speed of dolphins and the silent flight of owls. Owls locate their prey by hearing and need to fly silently. In both cases it has something to do with the soft pliable surface of the moving body and the wavy pattern that occurs on the dolphin skin and the owl feathers. Our objective was to investigate whether a pipe lined with a hairy soft carpet would “laminarize” air flows. The degree of laminarization was determined by the velocity profile. Manual pressure measurements were done to determine the air velocity at cross-sections along the pipe. Varying flow rates were tested before the hair was cut increasingly shorter. It was found that for some hair lengths the velocity profile approached the parabolic form of laminar flow at very high Reynolds number. VL - 3 IS - 4 ER -