Constructal Law and the Unifying Principle of Design

Part of the series Understanding Complex Systems pp 1-20


The Constructal Design of Humanity on the Globe

  • A. BejanAffiliated withDepartment of Mechanical Engineering and Materials Science, Duke University Email author 
  • , Sylvie LorenteAffiliated withLMDC (Laboratoire Matériaux et Durabilité des Constructions), Université de Toulouse

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Energy and water are commonly described as “problems,” like not having enough money in the bank. In this chapter we show that energy and water are not “commodities,” rather they are flows that sustain human life. They are not two flows but one flow, which is responsible for all the needs of human life (movement, heating, cooling, fresh water). This single flow represents wealth and is the reason why the annual economic activity of a country (the GDP) is proportional to the annual consumption of fuel in that country. All things move because they are driven. All the live systems (animate and inanimate) function as engines connected to brakes, such that the ultimate effect of fuel consumption is movement on the world map. To be most effective, this movement is hierarchical: few large and many small engines connected to brakes, all forming a multiscale tapestry (vasculature) of movement on the globe. The tapestry is a superposition of numerous distributing and collecting flow architectures, all linking discrete points with finite spaces (areas and volumes). The spaces covered by collecting and distributing flows grow in time in accord with S-shaped curves, which unite all the animate and inanimate flow designs on the landscape, and are predicted entirely based on the constructal law.