Percolation

From Wikipedia, the free encyclopedia
Jump to: navigation, search
In coffee percolation, soluble compounds leave the coffee grounds and join the water to form coffee. Insoluble compounds remain within the coffee filter.

In physics, chemistry and materials science, percolation (from Lat. percōlāre, to filter or trickle through) refers to the movement and filtering of fluids through porous materials.

Background[edit]

During the last five decades, percolation theory, an extensive mathematical model of percolation, has brought new understanding and techniques to a broad range of topics in physics, materials science, complex networks, epidemiology, and other fields . For example, in geology, percolation refers to filtration of water through soil and permeable rocks. The water flows to groundwater storage (aquifers)

Percolation typically exhibits universality. Statistical physics concepts such as scaling theory, renormalization, phase transition, critical phenomena and fractals are used to characterize percolation properties. Combinatorics is commonly employed to study percolation thresholds.

Due to the complexity involved in obtaining exact results from analytical models of percolation, computer simulations are typically used. The current fastest algorithm for percolation was published in 2000 by Mark Newman and Robert Ziff.[1]

Examples[edit]

  • Coffee percolation, where the solvent is water, the permeable substance is the coffee grounds, and the soluble constituents are the chemical compounds that give coffee its color, taste, and aroma
  • Movement of weathered material down on a slope under the earth's surface
  • Cracking of trees with the presence of two conditions, sunlight and under the influence of pressure
  • Robustness of networks to random and targeted attacks
  • Transport in porous media
  • Epidemic spreading
  • Surface roughening

See also[edit]

References[edit]

Further reading[edit]

External links[edit]