Atmospheric pressure discharge
Encyclopedia
An atmospheric pressure discharge is an electrical discharge in air at atmospheric pressure
.
An electrical discharge is a plasma
, which is an ionized gas
. Plasmas are sustained if there is a continuous source of energy to maintain the required degree of ionization and overcome the recombination events that lead to extinction of the discharge. Recombination events are proportional to collisions between molecules and thus to the pressure of the gas. Atmospheric discharges are thus difficult to maintain as they require a large amount of energy.
Typical atmospheric discharges are:
Atmospheric pressure
Atmospheric pressure is the force per unit area exerted into a surface by the weight of air above that surface in the atmosphere of Earth . In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point...
.
An electrical discharge is a plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
, which is an ionized gas
Gas
Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...
. Plasmas are sustained if there is a continuous source of energy to maintain the required degree of ionization and overcome the recombination events that lead to extinction of the discharge. Recombination events are proportional to collisions between molecules and thus to the pressure of the gas. Atmospheric discharges are thus difficult to maintain as they require a large amount of energy.
Typical atmospheric discharges are:
- DC arcElectric arcAn electric arc is an electrical breakdown of a gas which produces an ongoing plasma discharge, resulting from a current flowing through normally nonconductive media such as air. A synonym is arc discharge. An arc discharge is characterized by a lower voltage than a glow discharge, and relies on...
- LightningLightningLightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...
- Atmospheric Pressure Glow Discharge (APGD)
- Dielectric Barrier DischargeDielectric barrier dischargeDielectric-barrier discharge is the electrical discharge between two electrodes separated by an insulating dielectric barrier. Originally called silent discharge and also known as ozone production discharge or partial discharge, it was first reported by Ernst Werner von Siemens in 1857.- Process...
(DBD)