Brush Discharge


Also found in: Dictionary, Thesaurus, Wikipedia.

brush discharge

[¦brəsh ¦dis‚chärj]
(electricity)
A luminous electric discharge that starts from a conductor when its potential exceeds a certain value but remains too low for the formation of an actual spark.

Brush Discharge

 

a form of electric discharge in gases.

Brush discharges arise when one of the electrodes is a thin, sharp point, generating a highly nonuniform electric field. The elementary processes of the brush discharge are similar to those of the spark discharge, which the brush discharge becomes when the voltage between electrodes is increased. Unlike the spark discharge, in the brush discharge the bundle of sparks (brush) diverging from the point does not reach the second electrode. This and other features make it possible to consider the brush discharge a form of corona discharge with strongly pronounced intermittent phenomena. Lowering the voltage turns a brush discharge into an ordinary corona discharge.

St Elmo's fire

St Elmo's fire
A discharge of static electricity often seen when an aircraft flies through cumulus or other heavily charged clouds. The potential gradient around the aircraft and the surrounding air increases to an extent that a discharge takes place from sharp points in the form of visible light. Such a discharge is luminous and audible. Also called a corona discharge or a brush discharge.