WIND TUNNEL STUDIES OF ANTENNA BREAKDOWN. PART II. SHEATH SIMULATION IN THE WIND TUNNEL.
Abstract
This report describes the studies that have been carried out to illustrate the effect of velocity in the breakdown of a VHF antenna. The report describes the effect of mounting position and the effect of water vapor content in the wind stream on the antenna breakdown. The report also describes the initial operation of an arc jet to be used as a source of electrons in the wind stream for antenna breakdown testing. Ion density and electron temperature measurements were made in the ionized nitrogen layer over the X-band antenna using a double Langmuir probe. Results of a one-dimensional analysis indicate ion densities between 10 to the 10th power and 10 to the 11th power particles/cc and an ionized layer thickness of about 0.3 inches. Electron temperatures seemed low and circuit drift is the possible explanation. Charged particle densities calculated from measured enthalpies were higher than those derived from the probe data. Extension of the range of the plasma jet to higher charged particle densities is discussed. The range of parameters in the experiment pertinent to the Langmuir probe problem is presented and the use of more exact theories is discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1965
- Accession Number
- AD0622270
Entities
People
- Eugene E. Covert
- James B. Coffin Jr.
- Laurence R. Boedeker
Organizations
- Massachusetts Institute of Technology