The constructal law of design and evolution in nature.

Journal Article, Research Support, U.S. Gov't, Non-P.H.S.

Constructal theory is the view that (i) the generation of images of design (pattern, rhythm) in nature is a phenomenon of physics and (ii) this phenomenon is covered by a principle (the constructal law): 'for a finite-size flow system to persist in time (to live) it must evolve such that it provides greater and greater access to the currents that flow through it'. This law is about the necessity of design to occur, and about the time direction of the phenomenon: the tape of the design evolution 'movie' runs such that existing configurations are replaced by globally easier flowing configurations. The constructal law has two useful sides: the prediction of natural phenomena and the strategic engineering of novel architectures, based on the constructal law, i.e. not by mimicking nature. We show that the emergence of scaling laws in inanimate (geophysical) flow systems is the same phenomenon as the emergence of allometric laws in animate (biological) flow systems. Examples are lung design, animal locomotion, vegetation, river basins, turbulent flow structure, self-lubrication and natural multi-scale porous media. This article outlines the place of the constructal law as a self-standing law in physics, which covers all the ad hoc (and contradictory) statements of optimality such as minimum entropy generation, maximum entropy generation, minimum flow resistance, maximum flow resistance, minimum time, minimum weight, uniform maximum stresses and characteristic organ sizes. Nature is configured to flow and move as a conglomerate of 'engine and brake' designs.

Full Text

Duke Authors

Cited Authors

  • Bejan, A; Lorente, S

Published Date

  • May 12, 2010

Published In

Volume / Issue

  • 365 / 1545

Start / End Page

  • 1335 - 1347

PubMed ID

  • 20368252

Electronic International Standard Serial Number (EISSN)

  • 1471-2970

Digital Object Identifier (DOI)

  • 10.1098/rstb.2009.0302

Language

  • eng

Citation Source

  • PubMed