THERMAL SCIENCE

International Scientific Journal

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Antonio Heitor Reis

,

Antionio Ferreira Miguel

CONSTRUCTAL THEORY AND FLOW ARCHITECTURES IN LIVING SYSTEMS

ABSTRACT
We apply Constructal theory to the study of the flow structure of the human respiratory tree. We show that the flow architecture that would per form oxygenation of the blood and removal of carbon dioxide best, i. e. with lowest resistance, would be composed of a channel system with 23 bifurcation with a diffusive zone (alveolus) at the end. As this tree matches the human respiratory tree we conclude that nature has optimized it in time. Two constructal relation ships also emerge: (1) the length l, de fined by the ratio of the square of the airway diameter to its length, is constant for all individuals of the same species, and (2) the length γ is related to the volume of the space al located to the respiratory process, to the length of the respiratory tree and to the area of the alveoli, and determines univocally the branching level of the respiratory tree.
KEYWORDS
flow architectures, living systems, constructal theory
PAPER SUBMITTED: 2004-12-02
PAPER REVISED: 2005-01-23
PAPER ACCEPTED: 2006-02-13
DOI REFERENCE: https://doi.org/10.2298/TSCI0601057R
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2006, VOLUME 10, ISSUE Issue 1, PAGES [57 - 64]
REFERENCES
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Constructal theory and flow architectures in living systems

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence