ΘΕΩΡΗΤΙΚΗ ΜΕΛΕΤΗ ΤΗΣ ΣΥΜΠΕΡΙΦΟΡΑΣ ΗΛΕΚΤΡΙΚΗΣ ΕΚΚΕΝΩΣΗΣ ΣΕ ΜΙΚΡΑ ΔΙΑΚΕΝΑ
THEORETICAL PREDICTIONS ARE GIVEN OF THE DEVELOPMENT OF THE BREAKDOWN MECHANISMS AND OF THE FORMATION OF CATHODE AND ANODE REGIONS IN SMALL GAPS AT HIGH (760 TORRS) AND LOW (50 TORRS) PRESSURE. THE APPLIED FIELD IS DETERMINED BY THE ELECTRODE GEOMETRY AND THE EVOLUTION OF POSITIVE AND NEGATIVE IONS AND ELECTRONS ISDESCRIBED BY ONE-DIMENSIONAL CONTINUITY EQUATION IN CONJUCTION WITH THE POISSON'S EQUATIONS WHICH ARE RESOLVED BY AN ACCURATE NUMERICAL METHOD. THE EFFECTS OF IONIZATION, RECOMBINATION, ATTACHMENT AND ION SECONDARY-ELECTRON EMISSION FROM THE CATHODE ARE ALL INCLUDED. THE RESULTS OBTAINED AGREE SATISFACTORILY WITH EXPERIMENTAL VALUES. THE MAIN MECHANISM OF BREAKDOWN IS THAT OF THE STREAMER AND THE FEATURES OF HIS FORMATION CAN BE UNDERSTOOD BY NOTING THAT ANY CHANGE IN THE ELECTRIC FIELD IN N2 AND IN ATMOSPHERIC AIR CAUSES ABRUPT CHANGES IN THE ELECTRON DENSITY DUE TO EITHER STRONG NET ATTACHMENT OR STRONG NETIONIZATION WHICH BALANCE AT THE CRITICAL ELECTRIC FIELD . IN THE STREAMER HEAD THE NET CHARGE ENHANCES THE FIELD AHEAD OF THE STREAMER AND DEPRESS THE FIELD BEHIND. WHEN THESTREAMER HEAD APPROACHES THE CAFHODE A CAFHODE FALL REGION IS FORMED IMMEDIATELY ADJACENT TO THE CATHODE FOLLOWED BY A DISTURBANCE IN THE ANODE FALL REGION ESPECIALLY SIGNIFICANT FOR THE ELECTRONEGATIVE GASES. THE LATTER PROPAGATES TOWARDS THE CATHODE WITH A SPEED LESS THAN THAT OF STEAMER PROPAGATION. THUS A SECONDARY STREAMER IS FORMATED.
ΑΝΟΔΙΚΗ ΠΕΡΙΟΧΗ-ΔΕΥΤΕΡΟΓΕΝΗΣ STREAMER, ΑΝΟΜΟΙΟΓΕΝΕΣ ΗΛΕΚΤΡΙΚΟ ΠΕΔΙΟ, ΗΛΕΚΤΡΙΚΗ ΔΙΑΣΠΑΣΗ ΜΙΚΡΩΝ ΔΙΑΚΕΝΩΝ, ΚΑΘΟΔΙΚΗ ΠΕΡΙΟΧΗ, ΜΗΧΑΝΙΣΜΟΙ ΔΙΑΣΠΑΣΗΣ, ΠΡΩΤΟΓΕΝΗΣ STREAMER, ANODIC REGION-SECONDARY STREAMER, BREAKDOWN MECHANISMS, CATHODE FALL REGION, NON-UNIFORM ELECTRIC FIELD, PRIMARY STREAMER, SMALL GAPS ELECTRICAL BREAKDOWN, Επιστήμες Μηχανικού και Τεχνολογία, Επιστήμη Ηλεκτρολόγου Μηχανικού, Ηλεκτρονικού Μηχανικού, Μηχανικού Η/Υ, Engineering and Technology, Electrical Engineering, Electronic Engineering, Information Engineering
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