A SHOCK TUBE STUDY OF THE COUPLING OF THE 02-Ar RATES OF DISSOCIATION AND VIBRATIONAL RELAXATION
Abstract
The purpose of this investigation was to determine how the dissociation rate will be affected by a lack of vibrational equilibrium. Studies of the dissociation rate of dilute O2 - Ar mixtures were made in a 24 in. diameter shock tube from 5000 - 18,000 deg K. The O2 concentration was monitored by its absorption of 1470A radiation. An Arrhenius plot of the data yielded a straight line from 5000 - 11,000 deg K, the rate constant being given by kd = 2.9 (! 12%) x 10 to the 14th power exp (-D/RT) cc/mole-sec. Above 11,000 degrees the data deviate from the line given by this equation - at 18000 degrees kd being .45 times the calculated value. An incubation time, t, was observed during which dissociation does not proceed to a significant extent. The ratio of this incubation time to the vibrational relaxation time (obtained by extrapolating Camac's low temperature results) when plotted against translational temperature, displays a slight negative temperature dependence. At 18,000 degrees t/ v=0.4, at 8000 degrees t/ v=1, and at 5500 degrees we estimate that t/ v 2.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1962
- Accession Number
- AD0274095
Entities
People
- Kurt L. Wray