Constructal Theory

Adrian Bejan, 1996

Constructal Law

"For a finite-size system to persist in time (to live), it must evolve in such a way that it

provides easier access to the imposed currents that flow through it."

-Bejan, 1996-

Constructal Theory Flow systems under size-constraint Tree architecture predicted

Tree/Vascular/Dendritic

Applications

River delta

Tree (and roots)

Vascular

3D microvascular

Heat dissipation under skin

Airport

Dendritic

Chip cooling

Towards chip cooling

Heat transfer (cooling)

Combustor

Heat exchanger design

Cross flow heat exchanger

From principle to shape

Principles Every system will remain imperfect The best that can be done is to optimally

distribute imperfections Imperfections distribute to the smallest

scale of system This optimal distribution will result in the

geometry/shape of the system The perfect form is the least imperfect form

possible.

Analogies