TRANSITION (BENARD's)
| Collection | International Encyclopedia of Systems and Cybernetics |
|---|---|
| Year | 2004 |
| Vol. (num.) | 2(2) |
| ID | ◀ 3621 ▶ |
| Object type | Methodology or model |
- “The crossing from a molecular chaos dominated regime … to a much more complex one where part of the energy is transfered into macroscopic fluid currents” (adapted from R. LEFEVER, 1979, p.13).
In BÉNARD's experiment — heating a jar of water — this phenomenon starts with convection currents within the jar, replacing the simple thermic agitation. When the liquid nears the boiling point, the accelerating convection currents lead to the appearence of hexagonal structures: BÉNARD's dissipative structures. This phenomenon seemed merely a cusiosity until PRIGOGINE did generalize it as excess energy dissipation through giant fluctuations in systems far-from-equilibrium. Without such an energy flow, “the possibilities of formation of dissipative structures are absolutely negligible” (Ibid, p.15).
It is now well established that BÉNARD's transition is a very general phenomenon, even in biological and social systems, as shown for example by P.M. ALLEN's and colleagues work on urban systems (for instance 1984, p.230-248).
See also
Instability (B\'ENARD's)