Luchtwater

Luchtwater is a Dutch term that literally means air-water and is used to describe a two-phase system where air and water are present and interact. It covers situations where water exists in the gaseous phase as water vapor dispersed in the air, or where water and air are in close contact in a liquid–gas interface. In meteorology and climatology, the concept is central to humidity, water vapor pressure, dew point, condensation, fog and clouds; the amount of water vapor in air is usually expressed as relative humidity or specific humidity, and phase changes are driven by temperature.

In physics and environmental science, the exchange of gases between air and water bodies occurs across interfaces, governed by Henry's law and gas transfer velocities; this exchange controls oxygen availability in lakes and rivers, carbon dioxide uptake, and pollutant transport.

In technology, luchtwater describes systems using air and water as working media. Examples include air-to-water heat pumps, where outside air provides heat to water-based heating systems, and air-water coolers; in water treatment and process engineering, air-water contact is used for aeration, oxidation, and mass transfer in scrubbers and bubble columns. Luchtwater interfaces are also key in humidification, where moisture is added to air for comfort, process control, or industrial drying.