condensation
As condensation (also condensation or condensation ) refers to the water that condenses on a cool surface of objects once steam-containing air or gas containing water vapor there under the dew point is cooled. The formation of water ( condensation ) on surfaces in the open space is also referred to as dew or with the generic term fogging , the condensation on technical objects as condensation or fogging .
If the moisture condenses from air containing water vapor, the condensate can also contain condensable air pollutants (for example acid rain or volatile organic compounds ).
Other names
Condensed water that does not condense on a solid surface, but rather floats in the air or in a gas, is called wet steam , haze , fog or rain , depending on its appearance . If fog settles on surfaces, this is known as fog dew .
Utility applications
- Water recovery in thermal power plants
- Flue gas condensation for heat recovery in condensing boilers or in an air / flue gas system
- Condensation in deserts through nets set up at night
The principle is also used for gas cleaning, the recovery of solvents or the separation of substances in cold traps , but apart from water also for other substances.
Undesirable effects
- Condensation in chimneys ( sooting ), exhaust pipes and wind instruments
- Condensation on optical surfaces and isolators
- Condensation in air conditioning systems
- Condensation on the inside or in the component of building walls with poor thermal insulation
- Condensation on the window in the edge area of the glazing bead
- Sugar bloom in chocolate products
Avoidance of condensation
The formation of condensation water inside packaging or hermetically sealed housings is often prevented with desiccants .
Condensation on the window can be avoided by regular ventilation (3 to 5 times a day), increasing the room temperature or by heating the glass edge seal with an electric window heater. These are thin (approx. 3.5 mm diameter) heating elements which are glued to the window pane next to or behind the glass strip. It runs once around the perimeter of the visible glass surface and heats this area evenly. approx. 2/3 of the energy used (approx. 10 W / m / h) is released back into the living space as radiant heat. This also largely prevents the cold air drop from windows that is known in winter.
The formation of condensation within the thermal insulation of a building can be the cause of the growth of mold on the walls. It can be prevented by attaching a vapor barrier .
