STUDY OF ELECTRICAL BREAKDOWN CONDITIONS IN THE AERODYNAMIC FLOW FIELD OF A HYPERSONIC VEHICLE
Abstract
Theoretical methods for prediction of ionization growth and breakdown phenomena in gases subject to ac electric fields are analyzed. The applicability and extension of these methods to breakdown in the shock layer of a hypersonic vehicleARE EXAMINED. An understanding of these phenomena involves a description of the behavior of the electron velocity-distribution function. One cannot approximate the electron velocity distribution as Maxwellian without introducing considerable error. A simple criterion is developed for the applicability of time-relaxed or stationary velocity-distribution function to hypersonic flight considerations. Analysis of pulsed c.w. experiments indicate an upper limit for the velocity-distribution relaxation time which easily encompasses the relaxation time predicted from the criterion and therefore does not provide a critical test for the criterion. The criterion predicts that the time-relaxed distribution function is applicable to almost all reentry problems under consideration. The use of dc measured macroscopic parameters such as mobility, ionization (Townsend) coefficient, attachment coefficient, etc., tacitly assumes a stationary velocity distribution. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 30, 1962
- Accession Number
- AD0285585
Entities
People
- Boris Ragent
- Morton Rudin