This paper draws attention to the 1996 constructal theory of the generation of geometric form in flow systems. Flow architecture can be reasoned on the basis of principle: the maximization of global performance subject to finite-size constraints. One example is the generation of tree-shaped flow patterns, as optimized paths between one point (source, sink) and an infinity of points (area, volume). The optimized tree-flow architecture accounts for allometric laws, for example, the proportionality between metabolic rate and body size raised to the power 3/4, and the proportionality between breathing and heart beating times and body size raised to the power 1/4. Another example is the proportionality between the cruising speed of flying bodies (insects, birds, airplanes) and body mass raised to the power 1/6. The "thermodynamics law" status of the constructal principle is discussed.
展开▼
