Shape and Structure, from Engineering to Nature

by Adrian Bejan

Seemingly universal geometric forms unite the flow systems of engineering and nature. In this groundbreaking book, Adrian Bejan considers the design and optimization of engineered systems and discovers a relationship to the generation of geometric form in natural systems. The idea that shape and structure spring from the struggle for better performance in both engineering and nature is the basis of his new constructal the objective and constraints principle in engineering is the same mechanism underlying the geometry in natural flow systems. From heat exchangers to river channels, Bejan draws many parallels between the engineered and natural worlds. Numerous illustrations, examples, and homework problems make this an ideal text for engineering design courses. Its provocative ideas will also appeal to a broad range of readers in engineering, natural sciences, economics, and business.

362 pages, Hardcover

First published January 15, 2000

About the author

Adrian Bejan (MIT, 1971, 1972, 1975) is an American professor and discoverer of the constructal law of design evolution in nature. He is J. A. Jones Distinguished Professor at Duke University. He published more than 620 articles, 29 books and is in top 100 of most cited engineers in the world. He is a member of the Academy of Europe, and received 18 honorary doctorates from universities in 11 countries.

Academy of Europe:
http://www.ae-info.org/ae/User/Bejan_...

Constructal Law: Astrobiology Magazine
http://www.astrobio.net/topic/solar-s...

Reviews

[Ben McFarland · Rating 5 out of 5]

This is the first engineering book that kept me up late in suspense. It actually did. I couldn't wait to see what new phenomenon Adrian Bejan would tie into his constructal theory. What we have here is a book that starts off telling about how to build a system coolant that will most effectively cool a hot computer chip. It turns out that the best way to cool an area is to build something that looks an awful lot like a tree. And then how to build a system that will best drain a basin. That system looks like a tree. In three dimensions, Bejan discusses the best shape for a cross-section, which looks like the cross-section of a tree branch, or an artery. Then the best way to transfer heat intermittently is to have a regular rhythm that matches the rate of breathing or heartbeat. And the best way to arrange a city around a central facility. Yep, it's a tree.


This may sound like those mathematicians who see fractals everywhere, but it's different in a few crucial ways. For one thing, fractals are built top-down and continue to infinite detail. That doesn't fit the real world -- after all, atoms are not fractal. It has to stop somewhere. Rather, constructal theory starts with the smallest element that can move heat or matter, and then it builds and array of those elements, then an array of the arrays, and on up. The patterns look fractal but they are built very differently. And the most important thing is that (for all those phenomena listed above) they are predictive.


Only a few times does Bejan stretch his theory too far. A short passage on life and death, and some of the social applications, seem to not account for all the variables. But that means the theory covers only 98 different phenomena rather than 100. It's not that big a deal.


This is a truly unifying theory that explains how chemical things, biological things, and human-engineered things best distribute their flows. Bejan even gets a few philosophical implications in there (though I think there are many more to develop upon reflection). It's something to keep you up at night in a good way. This is what science is for.