Ionization of air produced by strong shocks

"This dissertation provides theoretical predictions along with experimental results for electron concentrations behind a shock as a function of Mach number over a range from 11 to 20 using a combustion driven shock tube operating in air. These theoretical predictions represent an upper bound for chemical equilibrium. The model for air was 78.0880% nitrogen, 20.949% oxygen, 0.0300% carbon dioxide, 0 .9300% argon, 0.0025%neon, and 0.0005% helium. Also the theory of a double diaphragm shock tube with corresponding pressure ratio vs. Mach number relationships is provided. A computor [sic] program using iterative techniques for a succinct presentation covering the modifications and deviations from the perfect gas theory for most simple mixtures of test gases is included. This program utilizes the latest available equilibrium constants for various gases. Also, this dissertation describes a technique which allows the electron concentration to be continuously monitored as a shock wave passes. The author designed and built the instrumentation for the operation of the shock tube and the monitoring of the electron concentration. This instrumentation included a high pressure gas handling system, velocity measurement techniques, and a laser interferometer for electron concentration measurements. To provide uniform monochromatic light across the beam, a continuously working Helium-Neon laser with a spatial filter was employed. The number of electrons per cubic centimeter behind the shock was measured at Mach numbers of 17.6 and 18.1. The data obtained did not represent accurate quantitative values of electron concentrations due to the unknown composition of the test gas. However, the experimental results demonstrated the reproducibility of the data with the system used"--Abstract, page ii."

Name thesis:degree_name

Ph. D. in Mechanical Engineering

Grantor

University of Missouri--Rolla

Year dc:date.available

2016

Author dc:creator

• Joyner, Howard Sajon

• Mechanical Engineering

Repository record dc:identifier

https://scholarsmine.mst.edu/doctoral_dissertations/2200

OAI identifier oai:identifier

oai:scholarsmine.mst.edu:doctoral_dissertations-3202