townsend discharge การใช้

• The Townsend discharge is a good example of the creation of positive ions and free electrons due to ion impact.
• An arc can be initiated without a preliminary Townsend discharge; for example when electrodes touch and are then separated.
• The electrons collide with other gas molecules, knocking electrons off them and creating more positive ions in a chain reaction called a Townsend discharge.
• The ionization is considerably amplified within the tube by the Townsend discharge effect to produce an easily measured detection pulse, which is fed to the processing and display electronics.
• ;Discharges : Electrostatic discharge, corona discharge, Partial discharge, Avalanche breakdown, Glow discharge, Direct current discharge, Lichtenberg figure, Electrical treeing, Townsend discharge, Arc Flash Paschen's law
• Below the ionization voltage or breakdown voltage there is no glow, but as the voltage increases to the ionization point the Townsend discharge happens just as glow discharge becomes visible; this is the start of the normal glow range.
• The occurrence of Townsend discharge, leading to glow discharge breakdown shapes the current-voltage characteristic of a gas discharge tube such as a neon lamp in a way such that it has a negative differential resistance region of the S-type.
• A "'gas-filled tube "', also known as a "'discharge tube "', is an arrangement of electrodes in a gas within an ionizing the gas with an applied voltage sufficient to cause electrical conduction by the underlying phenomena of the Townsend discharge.
• Depending on the polarity of the high voltage electrode one distinguishes negative corona, formed around the cathode, and positive corona, formed around the anode . "'Negative corona "'is similar to the Townsend discharge, where the electrons, emitted by the cathode, accelerate in the electric field, ionize the gas in collisions with its atoms and molecules releasing more electrons, and thus creating an avalanche.