Why humans build fires shaped the same way

The clashing asymptotes define this behavior, and the method of intersecting the asymptotes18 pinpoints the architecture, the design. Photographs taken by Adrian Bejan.This article, published in the Nature Scientific Report, explain “why humans unwittingly build fires that look the same: edifices of fuel, as tall as they are wide. The pile of fuel is permeable, air invades it by natural convection and drives the combustion.“. The article “show that the hottest pile of burning fuel occurs when the height of the pile is roughly the same as its base diameter. Future studies may address the shape effect of wind, material type, and packing. Key is why humans of all eras have been relying on this design of fire “unwittingly”. The reason is that the heat flow from fire facilitates the movement and spreading of human mass on the globe“.

Constructal Law: Optimization as Design Evolution

Constructal invasion of a conducting tree into a conducting body, Kobayashi, H., Lorente, S., Anderson, R., and Bejan, A., 2013, “Trees and Serpentines in a Conducting Body,” Int. J. Heat Mass Transfer, 56(1–2), pp. 488–494. This article from the Journal of Heat Transfer unveils the physics meaning of optimization, knowledge and design evolution, and why these concepts and human activities are profoundly useful for human life.

The design in nature phenomenon facilitates access for everything that flows, evolves, spreads, and is collected: river basins, atmospheric and ocean currents, animal life and migration, and technology (the evolution of the “human-and machine species,” wealth, life). This phenomenon is summarized by the constructal law: the occurrence and evolution of designs in nature, its time direction.

Notably, the constructal law accounts for contradictory end-design statements such as minimum entropy production and maximum entropy production, and minimum flow resistance and maximum flow resistance.

What is a classic book?

Dante

In this online article, Peder Zane, co-author of the book “Design in Nature“, discusses the origin of the concept of “classic books”, and how it emerges as a flow architecture.

The constructal law shows that lists of great or classic books are hierarchical designs that arise naturally to organize the swelling flow of literature.

Copyrights:

Every snowflake is not unique

SnowflakeProfessor Bejan explain in this article from Mechanical Engineering, why every snowflake is not unique about its principle, the constructal law.

Every snowflake conforms to only one architecture: a flat star with six fishbones connected at the center.

What’s more, that structure is predictable provided that we recognize the underlying principle: first, that something flows, in this case heat, and, second, that the natural tendency of all flows is to evolve
into architectures that provide easier access.

It’s another example of the constructal law.