AN EXPERIMENTAL STUDY OF THE BEHAVIOR OF LARGE NEGATIVE IONS.
Abstract
A method is developed for the examination of electron capture by certain high molecular weight electronegative materials in gases of low molecular weight. The method relies on the fact that these materials have strong affinities for free electrons of thermal energy. The complete apparatus consists of a high-vaccum system, a mechanically pulsed ultraviolet light source, a mechanically driven magnetic pickup head with associated electronics for providing the pulsing sequence desired, and an attachment drift chamber. The latter consists of a photocathode, several guard rings to insure a uniform electric field, a control grid, and a collector anode whose current is read by means of an electrometer. The magnitude of the current as a function of time provides the necessary information regarding electron attachment by the constitutents present in the working medium. The reason for carrying out this study was to determine the mobilities of the large negative ions in various working media, in an effort to assess their potential value as charge carriers in an EHD generator. Experimental results are presented and discussed throughout the report. It has been found that the negative ions of certain high molecular weight perfluorocarbon materials have unusually low mobilities when mixed in limited amounts with gases of low molecular weight. It is concluded that application of these mobility data to EHD processes leads to an improvement in output efficiency by at least an order of magnitude. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 15, 1966
- Accession Number
- AD0488866
Entities
People
- Robert W. Crowe