perkolasjons

Perkolasjons is a term used in Norwegian to refer to percolation, the movement of a liquid through a porous medium or the spread of something through a network. In physics and engineering, perkolasjon describes the flow of fluids through soils, filters, or geological formations, driven by gravity and capillary forces, and often described by Darcy's law for saturated flow and by Richards' equation for unsaturated flow. The rate depends on porosity (fraction of void space) and permeability (ability of the medium to transmit fluids), as well as pore size distribution, moisture, temperature, and pressure gradient.

In filtration and wastewater treatment, perkolasjon describes how water or other fluids migrate through membranes or packed beds, affecting efficiency and breakthrough time. In groundwater hydrology, downward percolation controls recharge and contaminant transport; upward or lateral perkolation affects capillary rise and soil moisture distribution.

In percolation theory, a mathematical framework studies connectivity in random networks. Nodes (sites) or bonds (connections) are considered open with probability p; above a critical threshold pc there exists a spanning cluster that enables long-range connectivity. This theory helps model spread phenomena, material porosity, and network robustness.

Common methods include laboratory infiltration tests, column percolation tests, and imaging of pore structure. Models include Darcy's law for saturated flow, the Richards equation for unsaturated flow, and numerical simulations of percolation on lattices and random graphs. See also percolation theory, soil physics, and filtration science.