Observations on the Theory and Characteristics of Electrical Figures on Plates in Air with Particular Reference to their Speed of Growth

Electrical Engineering

Pleasants, John Gibson ; Unknown, Unknown

University:California Institute of Technology

Department:Engineering and Applied Science

关键词: Electrical Engineering;   

Others  :  https://thesis.library.caltech.edu/10100/1/Pleasants_JG_1933.pdf

美国|英语

来源: Caltech THESIS

【 摘 要 】

The fact that electrical figures in air at atmospheric pressuregrow with average velocities which lie in the range of from 10 to 10³km./sec., and which may extend beyond this range, depending on themagnitude of the voltage applied and the physical constants of theplate is verified. The velocity decreases with increasing size of thefigure. The effect of a variation in the capacitance between surfacesper unit area of the plate has been found to be greater for negativethan for positive figures, and has been found to decrease with increasingvoltage, for figures at the same stage of development. The maximumcurrent intake has been observed to be 22.5 amp. (an average for two figures inparallel) at 30 kv., rising to a value of 60 amp. at 42.5 kv.. Theeffective capacitance (of two figures in parallel) in one case rosefrom an initial value of practically zero to more than 8,000 cm., resultingin a reduction in maximum value of the voltage wave applied of25% of the open line value. The reduction in rate of rise of voltagefor the same case was 30%. The possibility of the use of such anarrangement for protection against over voltages is suggested. Thepolarity difference in the figures is a result of the difference indirection of the flow of charge, and is dependent on the constants ofthe plate, - - no predisposition to a fixed ratio being noted. Thebehavior of the figures is such as to verify the conclusions of otherauthors that figures of both polarities are formed by the movement ofelectrons alone.